Recombinant PCR applies to fulfill gene recombination by PCR thermal reaction.Over the twenty years,it has branched into three characteristic strategies:splicing by overlapping extension(SOE),jumping polymerase chain reaction(JPCR)and DNA shuffling.Recently,the technique aimed with exploiting natural source of different allele genes is developing up on simplification of experimental procedure,on trap for mutation and variation,and on highthroughput screening with technology of surface display and fluorescent probe.The recombinant PCR is increasesing value in broad range from biological basic research to bioengineering study.

Objective To study the natural history of mild cognitive impairment (MCI) progress to dementia and to evaluate the efficacy of acetylcholinesterase inhibitor (AChEI) donepezil on MCI.Methods Ninty-eight patients with MCI including amnestic MCI and non-amnestic MCI were retrospectively analyzed. The patients with donepezil or not were separately divided to two groups while they were matched by sex, age,degree of MCI and possession of the ApoE?4 allele.The rate of conversion from MCI to dementia, measured with the Mini-Mental State Examination (MMSE),Alzheimer's Disease Assessment Scale- Cognitive section(ADAS-Cog) and Wechsler Memory Scale-Revised (WMS-R),was compared between the two groups.Results In aMCI group,the rate of conversion dropped by 15.1% and 8.3% (P0.05).Conclusion Donepezil could postpone the conversion of MCI to dementia.

Objective:To investigate the in vivo absorption kinetics of caffeine at different intestine segments in rats.Methods: The rat intestine was cannulated for in situ recirculation.The absorption kinetics of caffeine,including the absorption segments of intestine,drug concentration and pH value,were investigated in all the rats under light anesthesia.Ultraviolet light spectrometry and high-performance liquid chromatography were used to determine the concentrations of phenol red and caffeine,respectively.Results: The absorption rate constants(Ka) of caffeine in the small intestine at the concentrations of 2.5,5,10 and 25 mg?L-1 were 0.252,0.247,0.304 and 0.232 h-1,respectively.The Ka values at pH of 7.8,6.8,and 5.4 were 0.267,0.274 and 0.247 h-1,respectively.The Ka values in the duodenum,jejunum,ileum,and colon were 0.112,0.099,0.095 and 0.069 5 h-1,respectively.Conclusion: Concentration and pH value have no obvious effect on the absorption kinetics of caffeine.Caffeine can be better absorbed in the duodenum,jejunum and ileum than in the colon.The absorption of caffeine in the intestine is a first-order process through passive diffusion mechanism.

Background:In the past decade, many researchers focused on to robot?assisted surgery. However, on long?term outcomes for patients with early?stage non–small cell lung cancer (NSCLC), whether the robotic procedure is superior to video?assisted thoracic surgery (VATS) and thoracotomy is unclear. Nonetheless, in the article titled “Long?term survival based on the surgical approach to lobectomy for clinical stage I non–small cell lung cancer: comparison of robotic, video assisted thoracic surgery, and thoracotomy lobectomy” by Yang etal. that was recently published in Annals of Surgery, the authors provided convincing evidence that the robotic procedure results in similar long?term survival as compared with VATS and thoracotomy. Minimally invasive procedures typically result in shorter lengths of hospital stay, and the robotic procedure in particular results in superior lymph node assessment.
Main body:Our propensity score?matched study generated high?quality data. Based on our ifndings, we see prom?ise in expanding patient access to robotic lung resections. In this study, propensity score matching minimized the bias involved between groups. Nevertheless, due to its retrospective nature, bias may still exist. Currently, the concept of rapid rehabilitation is widely accepted, and it is very diffcult to set up a randomized controlled trial to compare robotic, VATS, and thoracotomy procedures for the treatment of NSCLC. Therefore, to overcome this limitation and to minimize bias, the best approach is to use a registry and prospectively collected, propensity score?matched data.
Conclusions:Robotic lung resections result in similar long?term survival as compared with VATS and thoracotomy. Robot?assisted and VATS procedures are associated with short lengths of hospital stay, and the robotic procedure in particular results in superior lymph node assessment. Considering the alarming increase in the incidence of lung can?cer in China, a nationwide database of prospectively collected data available for clinical research would be especially important.

Adult ; Bone Transplantation ; Fibula ; transplantation ; Humans ; Male ; Maxilla ; surgery ; Osteogenesis, Distraction ; methods ; Surgical Flaps ; Zygoma ; transplantation

The aim of the present study is to investigate the effects of sequoyitol (Seq) on expression of eNOS and NOX4 in aortas of type 2 diabetic rats. Type 2 diabetic rats induced by high fat and high sugar diet and low dose of streptozotocin (STZ, 35 mg x kg(-1)) and were administered Seq (12.5, 25 and 50 mg x kg(-1) x d(-1)) for 6 weeks. The fasting blood glucose (FBG) and body weight were tested. Acetylcholine (Ach) induced endothelium-dependent relaxation and sodium nitroprusside (SNP) induced endothelium-independent relaxation were measured in aortas for estimating endothelial function. Aortic morphological change was observed with HE staining. The level of serum insulin was measured by radioimmunoassay. The total antioxidative capacity (T-AOC), malondialdehyde (MDA) and NO levels in aortas were determined according to the manufacturer's instructions. In addition, the expressions of eNOS and NOX4 in aortas were measured by immunohistochemisty, real-time PCR or Western blotting. The results showed that Seq significantly decreased FBG and insulin resistance, and improved aortic endothelium-dependent vasorelaxation function. The expressions of NOX4 and MDA content were obviously decreased, while the expression of eNOS, the levels of NO and T-AOC increased significantly in aortas of diabetic rats with Seq treatment. In conclusion, Seq protects against aortic endothelial dysfunction of type 2 diabetic rats through down-regulating expression of NOX4 and up-regulating eNOS expression.
Animals ; Aorta ; metabolism ; pathology ; Blood Glucose ; metabolism ; Body Weight ; Diabetes Mellitus, Experimental ; chemically induced ; metabolism ; physiopathology ; Diabetes Mellitus, Type 2 ; chemically induced ; metabolism ; physiopathology ; Hypoglycemic Agents ; pharmacology ; Inositol ; analogs & derivatives ; pharmacology ; Insulin ; blood ; Insulin Resistance ; Male ; Malondialdehyde ; metabolism ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Oxidation-Reduction ; drug effects ; Rats ; Rats, Sprague-Dawley ; Streptozocin ; Vasodilation ; drug effects

This article analyzes the status quo of sales supervision on medical devices through some aspects, including the relevant regulation system, the standards of sales admittance, the supervision team and the approval of business license. According to the exiting problems, some improving countermeasures are proposed for reference.
Materials Management, Hospital ; organization & administration

This paper focuses on issues needed to be clear towards the product quality supervision of medical devices in use. The life circle of medical devices, the supervision regarding its boundary, target, emphasis, basis and standards have been analyzed in turn. A clear and creative idea is also provided for theoretical exploration of the supervision on medical devices in use.
Materials Management, Hospital ; Quality Assurance, Health Care

OBJECTIVETo investigate the protective effect and mechanism of sequoyitol (Sep) on high glucose-induced human umbilical vein endothelial cells (HUVECs) injury.

METHODSHUVECs were cultured with high glucose (30 mmol/L) in the presence or absence of sequoyitol (0.1, 1 and 10 micromol/L) for 24 h. Cell proliferation was measured by BrdU marking and cell cycle was detected by flow cytometry. 2', 7'-dichlorofluorescein diacetate was used to evaluate intracellular reactive oxygen species (ROS) levels. The NO, malonydialdehyde (MDA) and H2O2 levels were determined by colorimetric method according to the manufacturer's instructions. The expression of endothelial nitric oxide synthase (eNOS) and NADPH oxidase 4 (NOX4) were measured by real-time PCR and Western blot.

RESULTSIn the present study, we found that sequoyitol pretreatment for 1 h significantly decreased cell injury, promoted cell proliferation. Meanwhile sequoyitol significantly down-regulated NOX4 expression and decreased the level of ROS, MDA and H2O2 and obviously increased NO levels and up-regulated eNOS expression.

CONCLUSIONSequoyitol alleviates high glucose-induced cell injuries in HUVECs via inhibiting oxidative stress and up-regulating eNOS expression.

Cell Proliferation ; Cells, Cultured ; Glucose ; toxicity ; Human Umbilical Vein Endothelial Cells ; drug effects ; metabolism ; Humans ; Hydrogen Peroxide ; metabolism ; Inositol ; analogs & derivatives ; pharmacology ; Malondialdehyde ; metabolism ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Oxidative Stress ; Reactive Oxygen Species ; metabolism

Objective To develop the methods for using 0.015 cc pinpoint chambers, 0.007 cc miniature chambers and diode detector to measure Multi-leaf collimator (MLC) small field in IMRT.Methods MAX4000 and Unidos electrometers were connected with different types of small chambers and diode detectors.MLC shaped fields of10 cm×10 cm, 6 cm×6 cm, 4 cm×4 cm, 3 cm×3 cm, 2 cm× 2 cm were defined at 100 cm SSD.The field sizes for the Varian accelerator were defined by the tertiary MLC, while the secondary jaws were kept at 10 cm × 10 cm field, with the monitor units of 250 MU.Each field was measured three times to obtain the average value.The readings of all small fields were normalized to 10 cm × 10 cm field values for comparison of measured and published output factors.Results The relative deviations of the MLC small field output factors from the published outputs are 1.0％ , 1.7％ , 1.5％ and 2.4％, respectively, for Unidos electrometer connected with 0.015 cc pinpoint chamber;0.2％, 0.8％, 0.8％ and 1.4％, respectively, for Unidos electrometer connected with 0.007 cc miniature chamber;and 0.1％, 0.5％, 0.5％ and 0.9％, respectively, for MAX4000 electrometer connected with 0.007 cc miniature chamber.Conclusions The 0.015 cc chamber-measured MLC output factors for 3 cm × 3 cm and 2 cm × 2 cm fields are excellent.As required by IAEA, the relative deviations of the measured output factor from the published output factor are within ± 2％ for 2 cm × 2 cm fields and ± 3％ for larger fields.The results measured using 0.007 cc chamber are better than those measured using 0.015 cc chamber.The measured results using the diode detector, normalized to the 10 cm × 10 cm field, are consistent with the minimum requirements and excellent when being normalized to the 4 cm × 4 cm field.For dosimetric consideration, MLC small field output factor should be measured using small chamber and diode detector.The method is accurate and reliable, therefore, all measured output factors for MLC small fields should be input into radiation treatment plan system.