Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) enables non-invasive imaging characterization of tissue vascularity with small molecular weight gadolinium chelates. Depending on this technique, tissue blood perfusion, microvessel permeability and extracellular leakage space can be obtained. The basic principles of two dynamic MRI techniques (T2*W and T1W DCE-MRI) and their applications in prostate cancer of DCE-MRI including diagnosis, differential diagnosis, formulation of treatment plan, evaluation of therapeutic reaction, detection of lesion recurrent were reviewed in this article.

0.05).[Conclusion]The technique of double-tunnel with double-bundle of TE for reconstruction of anterior cruciate ligament(ACL) can improve the knee stability at the different flexion degree(0?～90?) and is more efficiently than the technique of single-tunnel with single-bundle.

Objective To establish Walker-256 transplantation tumor model in SD Rats.To study of R2 * signal changes on murine Walker-256 tumor after inhaling Carbogen by blood oxygen level dependent (BOLD)-MR,and to explore the feasibility of BOLD-MRI on detecting tumor hypoxia.Methods Walker-256 tumor cell implanted subcutaneously in right lower abdomen of 95 female SD rats.MR was performed on the tumor-forming rats when the maximum diameter of tumor reached 1-3 cm,using a 3.0 T MR scanner equipped with a 3 inch animal surface coil BOLD-MRI was done by using a multiecho SPGR sequence during inhaling air and at 10 minute after inhaling Carbogen,respectively.All images were transferred to GE ADW 4.3 workstation,then a baseline R2* (R2 * a) and R2 * (R2 * b) after inhaling Carbogen of tumor was calculated using R2 Star analysis software and △R2 * was calculated through △R2 * =R2 * b-R2 * a,meanwhile the volume of tumor were calculated as well.The difference of R2 * signal preand post-inhaling of Carbogen was compared with a paired t test,Pearson correlation was calculated between R2 * a,△R2 * and the volume of tumor,respectively.The correlation between △R2 * and R2 * a was also assessed by Pearson correlation.Results Sixty-eight of ninety-five female SD rats formed the tumor (71.6％).The volume of tumor was from 352 to 13 173 mm3.Mean △R2* decreased significantly (-2.26 ±3.90) s-1 from (41.18 ±22.29) s-1 during breathing air to(38.91 ±21.35) s-1 10 min after inhaling Carbogen (t =4.01,P ＜ 0.01).△R2 * was inversely correlated with R2 * (r =-0.32,P ＜ 0.05).The △R2 * was well correlated with volume of tumor (r =0.35,P ＜ 0.05),but R2 * a was not correlated with volume of tumor(r =-0.03,P ＞ 0.05).Conclusions BOLD-MRI can detect the R2 * signal change of murine Walker-256 tumor pre-and post-inhaling of Carbogen.The R2 * signal showed significant decrease after inhaling Carbogen,however,the individual variation was remarkable.

BACKGROUND:At present, there is still lack of related reports about the aging process of in vitro cultured epidermal cells, since epidermal cells are seed cells necessary for the construction of tissue engineered skin, this articleis is aimed to investigate the biological property of normal human epidermal cells during aging process so as to provide a foundation for the selection of seed cells for tissue engineered skin OBJECTIVE: To observe the in vitro proliferation and aging property of human epidermal cells in order to provide a foundation for the proper selection of seed cells for tissue engineered skin.DESIGN: A self-comparative experiment.SETTING: Orthopedic Surgery Research Instioute of Weifang Medical College and the General Surgery Department of Weifang Medical College Affiliated Hospital.MATERIALS: This experiment was carried out at the Orthopedic Surgery Research Institute of Weifang Medical College, between September 2000and September 2002. Healthy foreskin tissue was obtained from 20 normal boys of 6-8 years old who received peritomy at the General Surgery Department of Weifang Medical College Affiliated Hospital.METHODS: Epidermal cells were obtained from normal young people for subculture. Cells were collected from different culture passages and taken as subjects, and their aging characteristics were assessed through morphological observation, population doubling time (PDT), immune cytochemistry and beta-galactosidase staining. MAIN OUTCOME MEASURES: ① The changes of the epidermal cell growth characteristics. ② The morphological changes of the epidermal cells. ③ The epidermal cell phenotypic changes. RESULTS: ① The clanges of the epidermal cell growth characteristics: Cells were in vitro cultured by monolayer for 9 passages, and PDT of P2 was the shortest. The cells showed strong proliferation in the first 5 passages.From P6, PDT was obviously prolonged, but the cells from P8 did not proliferate any longer. ② The morphological changes of epidermal cells: The primary cultured cells began to proliferate 3 days later, which accelerated 4 days later. The cells became approximately fused in about 1 week. The growth of epidermal cells was identified with a microscope and the immuno histological techniques. ③ The epidermal cell phenotypic changes: Along with the consecutive subculture, histological expression of beta-galactosidase was found to show an increasing tendency from weak expression (occupying 9% of the young cells) to strong expression (occupying 65% of aging cells), and the positive expression rate of beta-galactosidase was found to be remarkably correlated with cell passage age (r=0.87, P ＜ 0.01). CONCLUSION: ① Compared with young cells, aging cells displayed more obvious aging morphology and enzyme cyto-chemical characteristics.During the cell aging process, the PDT of cells showed an increasing tendency. ②Compared with young cells, the expression of beta-galactosidase in aging cells was remarkably increased, and this increase paralleled with the appearance of cell aging phenotype and the loss of cell proliferation capability, and reflects the aging degree of cells. ③ The in vitro cultured normal human epidermal cell aging model was established in this experiment. The results of this experiment indicated that epidermal cells from the 1st -5th passage (donators aged 16-18 years old) can be taken as the optimal seed cells for tissue engineered skin construction.

BACKGROUND: Fibroblasts are considered as seed cells necessary for the construction of tissue engineering skin. The ultrastructure of cells of various generations was observed under the electron microscope in the hope of providing foundation for proper selection of seed cells for tissue engineering skin.OBJECTIVE: To observe the ultrastructural changes of normal human fibroblasts during in vitro culture.DESIGN: Self-control observation.SETTING: Institute of Plastic Surgery, Weifang Medical College; Department of General Surgery affiliated to Weifang Medical College.MATERIALS: This experiment was carried out in the Institute of Plastic Surgery, Weifang Medical College, between September 2000 and September 2002. Healthy prepuce specimens were collected during posthetomy from normal boys aged 6-8 years after the informed consent was obtained from their guardians.METHODS: The normal human diploid fibroblasts were used to carry out consecutive subculture; cells were collected from different generations for morphological and ultrastructural observation under the inverted phase contrast microscope and transmission electron microscope.ture under the transmission electron microscope.microscope: Cells could pass on for 65-70 generations and survive for 280-300 days. Cells within 45 generations could grow rapidly, but gradually grew slowly after the 45th generation, and even displayed no proliferaunder the transmission electron microscope: There were no obvious changes in cell ultrastructure within 40 generations, but cells presented inward tolds of nucleus membrane from the onset of generations 41-65, with the ratio of cell nuclear/plasma reduced as well as cell surface process and microvilli also reduced.CONCLUSION: The ultrastructural change of in vitro cultured fibroblasts varied between different generations, which became obvious after the 41st generation, suggesting that fibroblasts within 40 generations are considered preferable seed cells for the construction of tissue engineering skin.

BACKGROUND: As the seed cells for construction of tissue engineered skin, fibroblasts directly decide the quality of tissue-engineered skin. During in vitro culture, collagen gene expression and response to epidermal growth factor (EGF) stimulation of the fibroblasts in different passages can be indicative of their proliferative capability for use as the seed cells for skin tissue engineering.OBJECTIVE: To observe the expression of type Ⅰ and Ⅲ collagen mRNA in fibroblasts cultured in vitro and fibroblast response to EGF stimulation, and thereby providing reference for the selection of optimal seed cells for tissue engineering.DESIGN: Self-controlled experiment.SETTING: Institute of Plastic Surgery, Weifang Medical College.MATERIALS: This experiment was carried out at the Institute of Plastic Surgery, Weifang Medical College between September 2000 and June 2002. The specimens of normal prepuce tissues excised by circumcision were obtained from 20 healthy boys at the age between 6 and 8 years on a voluntarily basis in the Department of General Surgery, Affiliated Hospital of Weifang Medical College.surgically excised prepuce by trypsin and type Ⅰ collagenase digestion. After cultured till 80% confluence, the cells were digested with mixed digescontrast microscope was used for dynamic observation of the cell morphology and growth status, and transmission electron microscopy and anti-vigen gene expression: Reverse transcriptase PCR (RT-PCR) was performed for amplification of type Ⅰ and Ⅲ collagen cDNA derived from the total sis of fibroblast response to EGF stimulation: The fibroblasts of P10 and P60passage were divided into treatment group with stimulation by the conditioned medium containing EGF and control group with treatment with only the conditioned medium. 3H-TdR incorporation assay was performed for analyzing the growth of the fibroblasts in response to EGF stimulation.lasts of different passages to EGF stimulation.decreased with cell passaging and 3H-TdR incorporation was lower in P60cells without significant difference between the treatment group and control group (132.5±23.6 vs 124.9±16.8, P ＞ 0.05) than in P10 cells with,however, significant difference between the two groups (512.8±56.4 vs 306.4±22.5, P ＜ 0.01).EGF stimulation is weaker than P10 cells, moreover additional EGF in the condition medium has no obvious regulation on the proliferation of P60cell growth, but extremely remarkable on P10 cells, implying along with the increase of cell passage, tritium-thymidine incorporation reduced and regulative capability of EGF on aging fibroblastic growth was also attenuated.

Regeneration of injured peripheral nerve is one of the recent research focuses. Many inspiring achievements have been made in such fields as choice of seeding cell source and proliferation in vitro. It is hopeful that nerve regeneration may be enhanced by combining the new techniques with microsurgery. In this paper, design and fabrication principles, key technologies, various applications, and new directions in the field of tissue engineered nerve are introduced. Much of this paper is devoted to the discussion of tissue engineered nerve in repair of peripheral nerve injury.

Objective To compare the diagnostic efficacy of digital mammography,ultrasonography and MRI for breast non-mass enhancement (NME).Methods The digital mammography,ultrasonography and MRI data of 1 1 6 patients with 123 NME lesions on MRI were analyzed retrospectively.Results 99 lesions were malignant and 24 lesions were benign according to the pathologiacl result.The sensitivity of digital mammography,ultrasonography and MRI was 72.73%,65.66%,and 84.85%,respectively;The specificity was 66.67%,79.1 7%,and 79.1 7%,respectively;The accuracy was 71.54%,68.29%,and 83.74%,respectively;The positive pretictive value was 90.00%,92.86%,and 94.88%,respectively;The negative pretictive value was 37.21%,35.85%,and 55.88%,respectively.The sensitivity,specificity,accuracy,positive pretictive value and negative pretictive value of MRI were obviously higher than those of digital mammography and ultrasonography (P <0.05).The difference between the combinations and MRI alone were no statistically significant.Conclusion MRI have better diagnostic value,and could be used as the first choice examination for breast NME lesions.

Objective To compare the results of thrombelastography (TEG) and the conventional coagulability test in patients with sepsis, and to discuss the value of TEG in monitoring blood coagulation dysfunction in patients with sepsis. Methods The clinical data of 92 adult patients with sepsis admitted to Department of Critical Care Medicine of the First Affiliated Hospital of Guangxi Medical University were retrospectively analyzed. The patients were divided into sequential organ failure assessment (SOFA) score ≥ 12 group (n = 47) and SOFA < 12 group (n = 45). Thirty-five non-sepsis adult patients with normal coagulation function served as control group. The venous blood was collected for conventional blood coagulation test and routine examination of blood, D-dimer, procalcitonin (PCT), and TEG, and the differences were compared among three groups. Correlations between SOFA and various indexes of patients with sepsis were analyzed by Spearman rank correlation method. Results As shown in the results of the conventional blood coagulation test, D-dimer was gradually increased with the aggravation of the disease, the values in non-sepsis, SOFA < 12, and SOFA ≥ 12 groups were 0.523 (0.273, 0.928), 0.863 (0.673, 4.221), and 4.118 (2.420, 5.653) mg/L respectively (Z = 25.163, P = 0.000). Platelet count (PLT) in SOFA ≥ 12 group was significantly lower than that of the SOFA < 12 group and non-sepsis group [×109/L: 28.6 (12.8, 48.9) vs. 257.3 (152.6, 339.8), 182.0 (118.0, 229.0), both P < 0.01]. There was no significant difference in prothrombin time (PT) and international normalized ratio (INR) among three groups, and it indicated that the conventional blood coagulation test might not respond quickly to the change in coagulation status of sepsis patients. As shown in the results of TEG, the values of reaction time (R value) and kinetics time (K value) in SOFA < 12 group were lower than those of the non-sepsis group [R value (minutes): 4.4 (3.6, 6.1) vs. 6.3 (6.0, 6.7), P < 0.01; K value (minutes): 1.1 (1.0, 1.5) vs. 1.5 (1.3, 1.8), P < 0.05], while they were higher in SOFA ≥ 12 group than those of the non-sepsis group [R value (minutes): 7.0 (5.7, 8.7) vs. 6.3 (6.0, 6.7), P > 0.05; K value (minutes): 4.2 (3.4, 7.1) vs. 1.5 (1.3, 1.8), P < 0.01]. The α angle, maximum amplitude (MA) and coagulation index (CI) in SOFA < 12 group were higher than those of the non-sepsis group [α angle (° ): 73.3 (68.5, 74.7) vs. 66.8 (62.2, 69.0), P < 0.01; MA (mm): 71.7 (61.9, 73.3) vs. 60.3 (58.2, 63.8), P < 0.01; CI: 3.1 (-0.1, 3.9) vs. 0.9 (-0.4, 1.3), P < 0.05], while they were lower in SOFA ≥ 12 group than those of the non-sepsis group [α angle (° ): 48.1 (36.6, 53.0) vs. 66.8 (62.2, 69.0), P < 0.01; MA (mm): 37.8 (30.0, 45.7) vs. 60.3 (58.2, 63.8), P < 0.01; CI: -5.6 (-8.4, -3.6) vs. 0.9 (-0.4, 1.3), P < 0.01]. The above results indicated that TEG could distinguish quickly the hypercoagulability and hypocoagulability status in septic patients. PCT in non-sepsis, SOFA < 12, and SOFA ≥ 12 groups were 0.27 (0.05, 1.80), 0.68 (0.10, 10.00), 41.10 (4.24, 100.00) μg/L respectively (Z = 195.475, P = 0.000), which indicate the severity of infectious disease. Correlation analysis results showed that SOFA score was negatively correlated with PLT, α angle, MA, and CI (r value was -0.853, -0.833, -0.881, and -0.859, respectively, all P = 0.000), and it was positively correlated with activated partial thromboplastin time (APTT), D-dimer, R value, K value, and PCT (r value was 0.381, 0.561, 0.587, 0.831, 0.775, respectively, P < 0.05 or P < 0.01), and non correlations was founded with PT, fibrinogen (FBG), and INR (r1 = 0.211, P1 = 0.233; r2 = -0.252, P2 = 0.142; r3 = 0.248, P3 = 0.148). Conclusions TEG can effectively monitor the change in coagulation in patients with sepsis, and distinguish the hypercoagulable and hypocoagulable state. TEG may be a valuable tool to evaluate degree and risk of sepsis objectively.

Objective To analyze the indications,techniques of MR-guided localization and the imaging features of breast lesion.Methods Hook wire localization was performed in 43 patients whose lesions were only detected by MRI,based on a 1.5 T MR scanner and a special MR biopsy positioning frame.The feasibility of operation and accuracy of localization were explored.Lesion features and pathologic findings were analyzed using Fisher exact test.Results A total of 37 patients (86.0％) with 38 lesions underwent MR-guided localization.Of the 6 patients canceled,the lesions were not obvious in 4 patients,and the positioning was difficult in 2 cases.Of the 38 lesions,17 were masses,20 were non-mass enhancement lesions,and one lesion was undetermined enhancement.There were 11 (28.9％) malignant lesions.The distribution of internal enhancement pattern was different between benign and malignant non-mass lesions (P =0.028),while the other morphological features between benign and malignant were not significantly different (P ＞ 0.05).Conclusions MR-guided localization provides an accurate and safe method for localizing the suspicious lesions on MRI.The morphological findings of these lesions are not characteristic for the differentiation of benign and malignant lesions.