With the continuous deepening of the concept of precision diagnosis and treatment for lung cancer, how to achieve higher efficiency and accuracy in the screening, diagnosis, and treatment pathways in clinical practice has become an important issue that urgently needs to be overcome. The current clinical difficulty lies in the fact that despite continuous advancements in imaging and molecular diagnostic technologies, there are still limitations in manual efficiency and subjective experience when it comes to massive data analysis and multi-scale feature extraction. Artificial intelligence (AI), especially algorithm systems based on deep learning, is an innovative technology capable of deeply empowering medical big data. This method utilizes algorithms such as convolutional neural networks, combined with radiomics, pathomics, and multi-modal data fusion analysis, demonstrating immense potential in early precise detection and benign-malignant differentiation of pulmonary nodules, digital pathological subtype recognition and non-invasive prediction of driver genes, precise 3D surgical planning and automatic delineation of radiotherapy target volumes, as well as dynamic risk warning during follow-up. This innovative technology provides a brand-new solution for realizing intelligent and individualized lung cancer diagnosis and treatment models. This consensus, based on the latest evidence from evidence-based medicine and combined with the development trends in the AI field and real-world clinical needs, was ultimately formed by gathering the consensus opinions of multidisciplinary experts in radiology, pathology, thoracic surgery, and other fields. The main content covers the application specifications of AI in the three core scenarios of lung cancer screening, diagnosis, and treatment, the technical standards for data collection and algorithm validation, as well as the ethical and regulatory challenges faced at the current stage. It aims to clarify the applicable boundaries of AI as a clinical auxiliary decision support tool, providing scientific guidance and standardized exploration directions for peers currently engaged in or planning to carry out AI-assisted clinical diagnosis, treatment, and translation of lung cancer.

Objective To fabricate a large-diameter vascular graft with a pore size gradient structure mimicking that of natural blood vessels, using poly-L-lactic acid (PLLA) and polycaprolactone (PCL) as base materials through electrospinning and ultrasonic pore-forming techniques, and to evaluate its application potential. Methods A three-layered tubular graft was fabricated from a PCL/PLLA blend (mass ratio 6 : 4) via electrospinning, followed by an ultrasonic pore-forming process to create a gradient porosity. The resulting graft (diameter: 2 cm, length: 4 cm) was implanted into the descending thoracic aorta of an experimental pig using an end-to-end anastomosis. Graft patency and anastomotic sites were monitored by computed tomography angiography (CTA) at 1 and 6 weeks post-surgery. After 2 months, the graft was explanted for systematic evaluation of vascular regeneration and repair through gross examination, histopathology (H&E and elastic fiber staining), immunohistochemistry [for ETS-related gene (ERG), Actin, and Vimentin], and scanning electron microscopy (SEM). Results Postoperative CTA confirmed excellent graft patency at both 1 and 6 weeks, with no evidence of thrombosis or anastomotic stenosis. Gross examination of the 2-month explant revealed a smooth luminal surface covered by neotissue. Histopathological analysis demonstrated that the graft successfully induced the formation of a three-layered structure resembling a native vessel wall, comprising endothelial cells, smooth muscle cells, and fibroblasts. Immunohistochemistry further verified coverage of the luminal surface by endothelial cells (ERG-positive), along with the presence of neosmooth muscle (Actin-positive) and fibroblasts (Vimentin-positive). Endothelial cells were observed adhering to the inner surface of the artificial vessel under SEM. Conclusion The biomimetic, three-layered PLLA/PCL large-diameter vascular graft, constructed via electrospinning and ultrasonic pore-forming, exhibits excellent short-term patency and biocompatibility in a large animal model. More importantly, it demonstrates a significant potential to promote host cell infiltration and achieve in situ regeneration of a three-layered vascular wall structure, providing a promising experimental basis for the development of next-generation functional vascular substitutes.

Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N⁶-methyladenosine (m⁶A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m⁶A methyltransferases (“writers”) catalyze the addition of a methyl group to the N⁶ position of adenosine, m⁶A demethylases (“erasers”) remove the modification, and m⁶A-binding proteins (“readers”) recognize m⁶A-modified transcripts. Through the coordinated actions of these factors, m⁶A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m⁶A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m⁶A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m⁶A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m⁶A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m⁶A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m⁶A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m⁶A-related proteins can function through noncanonical mechanisms independent of m⁶A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m⁶A regulatory system. Dysregulation of m⁶A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m⁶A-dependent and -independent mechanisms, the spatiotemporal dynamics of m⁶A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m⁶A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.

Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N⁶-methyladenosine (m⁶A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m⁶A methyltransferases (“writers”) catalyze the addition of a methyl group to the N⁶ position of adenosine, m⁶A demethylases (“erasers”) remove the modification, and m⁶A-binding proteins (“readers”) recognize m⁶A-modified transcripts. Through the coordinated actions of these factors, m⁶A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m⁶A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m⁶A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m⁶A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m⁶A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m⁶A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m⁶A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m⁶A-related proteins can function through noncanonical mechanisms independent of m⁶A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m⁶A regulatory system. Dysregulation of m⁶A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m⁶A-dependent and -independent mechanisms, the spatiotemporal dynamics of m⁶A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m⁶A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.

Polygonati Rhizoma demonstrates significant potential for addressing both chronic and hidden hunger. The supply of high-quality seedlings is a primary factor influencing the development of the Polygonati Rhizoma industry. Warm water soaking is often used in agriculture to promote the rapid germination of seeds, while its application and molecular mechanism in Polygonati Rhizoma have not been reported. To rapidly obtain high-quality seedlings, this study treated Polygonatum kingianum var. grandifolium seeds with sand storage at low temperatures, warm water soaking, and cultivation temperature gradients. The results showed that the culture at 25 ℃ or sand storage at 4 ℃ for 2 months rapidly broke the seed dormancy of P. kingianum var. grandifolium, while the culture at 20 ℃ or sand storage at 4 ℃ for 1 month failed to break the seed dormancy. Soaking seeds in 60 ℃ warm water further increased the germination rate, germination potential, and germination index. Specifically, the seeds soaked at 60 ℃ and cultured at 25 ℃ without sand storage treatment(Aa25) achieved a germination rate of 78. 67%±1. 53% on day 42 and 83. 40%±4. 63% on day 77. The seeds pretreated with sand storage at 4 ℃ for 2 months, soaked in 60 ℃ water, and then cultured at 25 ℃ achieved a germination rate comparable to that of Aa25 on day 77. Transcriptomic analysis indicated that warm water soaking might promote germination by triggering reactive oxygen species( ROS), inducing the expression of heat shock factors( HSFs) and heat shock proteins( HSPs), which accelerated DNA replication, transcript maturation, translation, and processing, thereby facilitating the accumulation and turnover of genetic materials. According to the results of indoor controlled experiments and field practices, maintaining a germination and seedling cultivation environment at approximately 25 ℃ was crucial for the one-year seedling cultivation of P. kingianum var. grandifolium.
Germination ; Seedlings/genetics* ; Water/metabolism* ; Seeds/metabolism* ; Polygonatum/genetics* ; Temperature ; Plant Proteins/genetics* ; Plant Dormancy

Medical institutions, with their clinical practice foundation and abundant human use experience data, have become important carriers for the inheritance and innovation of traditional Chinese medicine(TCM) and the "cradles" of the preparation of new TCM. To effectively promote the transformation of new TCM originating from the TCM clinical practice in medical institutions and establish an effective evaluation index system for the transformation of new TCM conforming to the characteristics of TCM, consensus experts adopted the literature research, questionnaire survey, Delphi method, etc. By focusing on the policy and technical evaluation of new TCM originating from the TCM clinical practice in medical institutions, a comprehensive evaluation from the dimensions of drug safety, efficacy, feasibility, and characteristic advantages was conducted, thus forming a comprehensive evaluation system with four primary indicators and 37 secondary indicators. The expert consensus reached aims to encourage medical institutions at all levels to continuously improve the high-quality research and development and transformation of new TCM originating from the TCM clinical practice in medical institutions and targeted at clinical needs, so as to provide a decision-making basis for the preparation, selection, cultivation, and transformation of new TCM for medical institutions, improve the development efficiency of new TCM, and precisely respond to the public medication needs.
Medicine, Chinese Traditional/standards* ; Humans ; Consensus ; Drugs, Chinese Herbal/therapeutic use* ; Surveys and Questionnaires

OBJECTIVE: To analyze the effectiveness of single three-dimensional (3D)-printed microporous titanium prostheses and flap combined prostheses implantation in the treatment of large segmental infectious bone defects in limbs. METHODS: A retrospective analysis was conducted on the clinical data of 76 patients with large segmental infectious bone defects in limbs who were treated between January 2019 and February 2024 and met the selection criteria. Among them, 51 were male and 25 were female, with an age of (47.7±9.4) years. Of the 76 patients, 51 had no soft tissue defects (single prostheses group), while 25 had associated soft tissue defects (flap combined group). The single prostheses group included 28 cases of tibial bone defects, 11 cases of femoral defects, 5 cases of humeral defects, 4 cases of radial bone defects, and 3 cases of metacarpal, or carpal bone defects, with bone defect length ranging from 3.5 to 28.0 cm. The flap combined group included 3 cases of extensive dorsum of foot soft tissue defects combined with large segmental metatarsal bone defects, 19 cases of lower leg soft tissue defects combined with large segmental tibial bone defects, and 3 cases of hand and forearm soft tissue defects combined with metacarpal, carpal, or radial bone defects, with bone defect length ranging from 3.8 to 32.0 cm and soft tissue defect areas ranging from 8 cm×5 cm to 33 cm×10 cm. In the first stage, vancomycin-loaded bone cement was used to control infection, and flap repair was performed in the flap combined group. In the second stage, 3D-printed microporous titanium prostheses were implanted. Postoperative assessments were performed to evaluate infection control and bone integration, and pain release was evaluated using the visual analogue scale (VAS) score. RESULTS: All patients were followed up postoperatively, with an average follow-up time of (35.2±13.4) months. In the 61 lower limb injury patients, the time of standing, walk with crutches, and fully bear weight were (2.2±0.6), (3.9±1.1), and (5.4±1.1) months, respectively. The VAS score at 1 year postoperatively was significantly lower than preoperative one ( t=-10.678, P<0.001). At 1 year postoperatively, 69 patients (90.8%) showed no complication such as infection, fracture, prosthesis displacement, or breakage, and X-ray films indicated good integration at the prosthesis-bone interface. According to the Paley scoring system for the healing of infectious bone defects, the results were excellent in 37 cases, good in 29 cases, fair in 3 cases, and poor in 7 cases. In the single prostheses group, during the follow-up, there was 1 case each of femoral prostheses fracture, femoral infection, and tibial infection, with a treatment success rate of 94.1% (48/51). In lower limb injury patients, the time of fully bear weight was (5.0±1.0) months. In the flap combined group, during the follow-up, 1 case of tibial fixation prostheses screw fracture occurred, along with 2 cases of recurrent foot infection in diabetic patients and 1 case of tibial infection. The treatment success rate was 84.0% (21/25). The time of fully bear weight in lower limb injury patients was (5.8±1.2) months. The overall infection eradication rate for all patients was 93.4% (71/76). CONCLUSION The use of 3D-printed microporous titanium prostheses, either alone or in combination with flaps, for the treatment of large segmental infectious bone defects in the limbs results in good effectiveness with a low incidence of complications. It is a feasible strategy for the reconstruction of infectious bone defects.
Humans ; Male ; Female ; Middle Aged ; Printing, Three-Dimensional ; Titanium ; Retrospective Studies ; Surgical Flaps ; Adult ; Prosthesis Implantation/methods* ; Plastic Surgery Procedures/methods* ; Treatment Outcome ; Prostheses and Implants ; Bone Diseases, Infectious/surgery* ; Extremities/surgery* ; Prosthesis Design

OBJECTIVE: To explore the effectiveness of additional anti-rotation steel plate assisted intramedullary nail technology in treatment of aseptic femoral non-union patients. METHODS: A retrospective analysis was conducted on 21 patients with aseptic femoral non-union who admitted between September 2020 and October 2024 and treated with additional anti-rotation steel plate assisted intramedullary nail technology. There were 17 males and 4 females, aged 25-67 years (mean, 44 years). There were 19 cases of femoral anterograde intramedullary nail fixation, 1 case of femoral retrograde intramedullary nail fixation, and 1 case of steel plate fixation with fatigue fracture. There were 9 cases of hypertrophic non-union and 12 cases of atrophic non-union. All patients had varying degrees of fracture end atrophy/sclerosis. Among them, 20 patients who were fixed with intramedullary nails underwent removal of soft tissue and hardened bone at the fracture end, and cortical treatment resulted in the appearance of "chili sign" at the fracture end. Iliac bone grafting and anti-rotation steel plate fixation were performed. One patient with steel plate fixation was removed the steel palte and fixed with a retrograde intramedullary nail, while the hardened bone at the fracture end was removed, iliac bone grafting and anti-rotation steel plate fixation were performed. Postoperative follow-up observation included the incision healing, maximum knee flexion range of motion, bone healing, length of lower limbs, and subjective satisfaction. The lower extremity functional scale (LEFS) score was used to evaluate the lower limb function. RESULTS: All incisions healed by first intention. All patients were followed up 7-26 months (mean, 15.5 months). At last follow-up, the femoral fracture healed with the obvious callus formation at the fracture end; the maximum knee flexion range of motion was 95°-127° (mean, 112.67°). The LEFS score increased from 29.9±6.7 before operation to 75.9±3.0 at last follow-up, and the difference was significant (t=-29.622, P<0.001). Except for 1 patient who underwent intramedullary nail dynamic treatment before operation and had a lower limb shortening of about 0.9 cm, the other patients had bilateral lower limbs of equal length. All patients had no postoperative infections, mal-union of fractures, deep vein thrombosis, joint stiffness, or other complications. CONCLUSION The use of additional anti-rotation steel plate assisted intramedullary nail technology in the treatment of aseptic femoral non-union not only overcomes the drawbacks of insufficient stability at the fracture end of intramedullary nails, but also overcomes the shortcomings of biased fixation with steel plates. It has the advantages of minimal trauma, effective maintenance of fracture stability, and ideal postoperative functional recovery, making it an effective treatment for aseptic femoral non-union.
Humans ; Male ; Fracture Fixation, Intramedullary/instrumentation* ; Female ; Bone Plates ; Middle Aged ; Adult ; Femoral Fractures/surgery* ; Retrospective Studies ; Bone Nails ; Aged ; Fractures, Ununited/surgery* ; Treatment Outcome ; Bone Transplantation/methods* ; Steel ; Fracture Healing

Severe hallux valgus, a triplanar foot deformity significantly impairing patients' quality of life, has witnessed progressive advancements in surgical management. This article systematically reviews the therapeutic progress through literature analysis, encompassing modifications of conventional surgical procedures and applications of novel techniques and innovative biomaterials. A critical analysis and discussion of these technological advancements and future developmental directions are presented to provide valuable insights and references for clinical management of severe hallux valgus.
Humans ; Hallux Valgus/surgery* ; Osteotomy/methods* ; Bone Transplantation/methods* ; Orthopedic Procedures/methods*

OBJECTIVE: To summarize the early clinical results and safety of Stand-alone OLIF application of lumbar lesions, and explored its surgical indications. METHODS: Total of 92 cases of lumbar spine lesions treated with Stand-alone OLIF at two medical centers from October 2014 to December 2018 were retrospectively analyzed, including 30 males and 62 females with an average age of (61.20±12.94) years old ranged from 32 to 83 years old. There were 20 cases of lumbar spinal stenosis, 15 cases of lumbar disc degeneration, 11 cases of lumbar degenerative spondylolisthesis, 6 cases of discogenic low back pain, 7 cases of giant lumbar disc herniation, 13 cases of primary lumbar discitis, 6 cases of adjacent vertebral disease after lumbar internal fixation surgery, and 14 cases of degenerative lumbar scoliosis. Pre-operative dual energy X-ray bone density examination 31 cases' T-values ranged from -1 to -2.4, 8 cases' T-values ranged from -2.5 to -3.5, and the rest had normal bone density. The number of fusion segments: 68 cases of single segment, 9 cases of two segment, 12 cases of three segment , and 3 cases of four segment. Fusion site:L_1,2 1 case, L_2,3 4 cases, L_3,4 10 cases, L_4,5 53 cases, L_2,3-L_3,4 3 cases, L_3,4-L_4,5 6 cases, L_1,2L_2,3L_3,4 1 case, L_1,2L_3,4L_4,5 1 case, L_2,3L_3,4L_4,5 10 cases, L_1,2L_2,3L_3,4L_4,5 3 cases. The clinical results and imaging results of this group of cases were observed, as well as the complications. RESULTS: The surgical time ranged from 40 to 140 minutes with an average of (60.92±27.40) minutes. The intraoperative bleeding volume was 20 to 720 ml with an average of (68.22±141.60) ml. The patients had a follow-up period of 6 to 84 months with an average of (38.50±12.75) months. The height of the intervertebral space recovered from (9.23±1.94) mm in preoperative to (12.68±2.01) mm in postoperative, and (9.11±1.72) mm at the last follow-up, there was a statistically significant difference(F=6.641, P=0.008);there was also a statistically significant difference between the postoperative and preoperative height of the intervertebral space(t=9.27, P<0.000 1);and there was also a statistically significant difference (t=10.06, P<0.000 1) between the last follow-up and postoperative height of the intervertebral space. At the last follow-up, cage subsidence grading was as follows:level 0 in 69 cases (76 segments), levelⅠin 17 cases (43 segments), level Ⅱin 5 cases (14 segments), and level Ⅲ in 1 case (1 segment);according to the number of segments, normal subsidence accounts for 56.72%, abnormal subsidence accounts for 43.28%. Bone mineral desity of normal subsidence groups was -0.50±0.07 whinch was better than that the abnormal subsidence groups -2.10±0.43, and the difference was statistically significant(χ²=2.275, P=0.014). As well as there was a statistically significant difference in the patient's VAS of backache from (6.28±2.11) in preoperative to (1.48±0.59) in last follow-up(t=8.56, P<0.05). The ODI recovered from (36.30±7.52)% before surgery to (10.20±2.50)% at the last follow-up, with a statistically significant difference (t=7.79, P<0.000 1). Complications involved 4 cases of intraoperative vascular injury, 21 cases of endplate injury, and 4 cases of combined vertebral fractures. The incision skin has no necrosis or infection. There were 4 cases of left sympathetic chain injury, 4 cases of transient left hip flexion weakness, 2 cases of left thigh anterolateral numbness with quadriceps femoris weakness, and 1 case of incomplete intestinal obstruction;8 cases were treated with posterior pedicle screw fixation due to fusion cage settlement accompanied by stubborn lower back pain, and 6 cases were treated with fusion cage settlement and lateral displacement. According to the actual number of cases, there were 38 complications, with an incidence rate of 41.3%. CONCLUSION The application of Stand alone OLIF in lumbar spine disease fusion has achieved good early results, with obvious clinical advantages, but also there are high probability of complications. It is recommended to choose carefully. It is necessary to continuously summarize and gradually clarify and complete the surgical indications and specific case selection criteria.
Humans ; Male ; Female ; Middle Aged ; Spinal Fusion/methods* ; Lumbar Vertebrae/injuries* ; Aged ; Adult ; Retrospective Studies ; Aged, 80 and over