Anti-retroviral (ARV) drugs have been successfully used for HIV/AIDS therapy,and their uses in pre-exposure prophylaxis (PrEP) for HIV infection is becoming increasingly important,and is drawing more attentions.Reports on seven large scale,multicentric clinical trials provide significant clinical data for further study and implementation of PrEP.This article reviews the current situation,necessity,questions,problems and prospects of PrEP for HIV infection.

BACKGROUND:Discogenic pain is a major cause of chronic low back pain,and its inflammation mechanism that is participated by many cytokines is well known by more and more people. However,what is the role of these cytokines in the occurrence and development of pain and how we use them to control pain are still not consistent. OBJECTIVE:To completely learn about the pathogenesis of intervertebral disk herniation,the relative cytokines in the occurrence and development of pain and the advances in the treatment of chronic pain with cytokines. RETRIEVE STRATEGY:A computer-based online search of CNKD was undertaken to identify the relevant articles dated from January 1994 to June 2007 with the Chinese of "cytokine,pain". And totally 153 articles were collected. Meanwhile,PubMed database was searched for English articles published from January 2002 to June 2007 with the keywords of "gene,chronic pain" and 36 were collected. The articles that involved the basic and clinical researches closely related with cytokine were selected. Repetitive articles were excluded. After the trail,6 Chinese and 24 English articles were involved. LITERATURE EVALUATION:Of the 30 articles,10 were focused on the basic research and animal experiment,and 20 were about clinical research. There were 7 of RCT,1 of EBM review,10 of summary analysis,2 of case report,and 10 of experience exchange. DATA SYNTHESIS:The mechanisms of discogenic pain include inflammation and immune ones besides mechanical pressure. Inflammation mechanism of discogenic pain is well known by more and more people,in which many cytokines such as substance P,phospholipase A2,tumor necrosis factor,interleukin,growth factor and NO participate. Meanwhile,the role of immunities should not be ignored. Some researchers have used some cytokines(interleukin 1 receptor antagonist,vascular endothelial growth factor,etc) in clinic to treat pains and got good effect. CONCLUSION:The mechanism of pain and various effects of pain-killer are based on gene. Cytokines play important roles in the occurrence,development and treatment of discogenic pain.

Isotope dilution mass spectrometry is a reliable principle for small molecule analyte measurements.It is a precise,accurate method with very high specificity,which is very suitable for lowconcentration steroid hormones tests.The published reference methods are all based on this principle so far.In this paper,the applications of isotope dilution mass spectrometry in the determination of steroid hormones were reviewed.

Objective To investigate the effect of EGB on SOD, MDA of ventilator-induced lung injury in rats and its possible mechanisms. Methods Thirty male SD rats were randomly divided into 3 groups: control group (C group), high tidal ventilation group (H group) and EGB group (E group). The setting mechanical ventilation was VT=30 mL/kg, RR=40/min, I/E=1/3, PEEP=0 cmH2 O and FiO2=21%. The broncho-alveolar lavage fluid (BLAF) and serum were obtained for determination of the levels of SOD and MDA at the end of 4 h mechanical ventilation. The Lungs were removed, and the wet-to-dry weight ratio (W/D) and pulmonary pathologic changes were measured. Results As compared with C group, W/D and the levels of MDA were significantly increased in H group, but the levels of SOD were reduced in H group. As compared with H group, W/D and the levels of MDA were significantly decreased in E group, but the levels of SOD were increased in E group. Pulmonary pathologic changes were alleviated in E group comparing with H group. Conclusion EGB injection may have a protective role against hyperoxia and induced pulmonary damage in rats.

Objective To evaluate the clinical effect of different doses of leuprorelin acetate in in vitro fertilization-embryo transfer(IVF-ET).Methods From January 2011 to December 2011,the data of 268 patients undergoing IVF and (or) intracytoplasmic sperm injection (ICSI) in Reproductive Medical Center,Clinical College of PLA,Anhui Medical University were studied retrospectively.All the patients were divided into three groups based on with long protocol and controlled ovarian stimulation (COH) including 83cycles with 1.25 mg of leuprorelin in low dose group,68 cycles with 1.88 mg of leuprorelin in high dose group,117 cycles with 1.25 mg of diphereline in control group.The serum follicle stimulating hormone (FSH),luteinizing hormone (LH),estradiol (E2) and progesterone (P) before gonadotropin (Gn)administration on the days 3-5 of the menstrual cycle and on the day of hCG administration were detected,the dose and duration of Gn,number of oocytes retrieved,number of mature oocytes,the rates of fertilization,embryo cleaved,good-quality embryos clinical pregnancy and early miscarriage were compared among three groups.Results There were no significant differences in age,the level of LH and P on the day of hCG administration among three groups (P ＞ 0.05).The level of FSH was (3.8 ± 1.6) U/L in low dose leuprorelin group,(3.1 ± 1.4) U/L in high dose of leuprorelin group and (2.4 ± 1.3) U/L in diphereline group before Gn administration,which reached statistical difference (P ＜ 0.05).The mean length of Gn stimulation were (9.8 ± 1.7) days in low dose leuprorelin group,(10.5 ± 1.8) days in high dose of leuprorelin group and (11.1 ± 1.4) davs in diphereline group,which reached statistical difference (P ＜0.05).The mean dose of Gn was (24 ± 7) in low dose of leuprorelin group,which was significantly higher than (27 ± 9) in high dose of leuprorelin group and (28 ± 7) in diphereline group (P ＜ 0.05).The level of LH was (2.7 ± 1.6) U/L in low dose of leuprorelin group and (2.2 ± 1.0) U/L in diphereline group before Gn administration,which reached statistical difference(P ＜ 0.05).The cancel cycles were 5 in low dose of leuprorelin group,4 in high dose of leuprorelin group and 7 in diphereline group.The number of ovum was (14 ±7) low dose of leuprorelin group,(13 ±6) in high dose of leuprorelin group,(14 ±6) in diphereline group.The rates of fertilization was 66.26％ (758/1144)in low dose of leuprorelin group,67.01％ (589/879) in high dose of leuprorelin group and 68.54％ (1111/1621) in diphereline group,the rates of goodquality embryos was 64.22％ (472/735) in low dose of leuprorelin group,60.50％ (340/562) in high dose of leuprorelin group and 59.59％ (640/1074) in diphereline group,clinical pregnancy was 49％ (38/78) in low dose of leuprorelin group,42％ (27/64) in high dose of leuprorelin group and 50％ (55/110) in diphereline group,early miscarriage was 18％ (7/38) in low dose of leuprorelin group,15％ (4/27) in high dose of leuprorelin group and 15％ (8/55) in diphereline group,which did not show significant differences (P ＞0.05).Conclusions Both 1.25 mg and 1.88 mg leuprorelin acetate could obtain good downregulation effect and clinical outcomes.1.25 mg leuprorelin acetate could decrease patient's costs by reducing Gn dose and duration.

This paper summarizes the features of web sites that would be useful to infectious diseases physicians by exploring the Internet through search engine including Google,Baidu and Yahoo.Meanwhile,suggestions from professional forums,web sites and publications are also taken into consideration.Nine Comprehensive sites containing three categories and more of microbial pathogens,nine special sites for parasites,four special sites for fungi,two special sites for viruses and two special sites for bacteria are collected.Subjective navigation for each site is given.Features of these sites,including laboratory images,clinical images and number of images are also described.

BACKGROUND:So far, the short-term changes of various organs after injection of umbilical cord mesenchymal stem cells have been reported, but there are few studies on the long-term changes of various organs in healthy rats after repeated intramuscular injection of umbilical cord mesenchymal stem cells. OBJECTIVE:To observe the security of intramuscular injection of heterogeneous umbilical cord mesenchymal stem cells. METHODS:Sixty male SPF Wistar rats were divided into six groups randomly:normal group (suspension liquid of umbilical cord mesenchymal stem cells);control group with culture solution;supernatant group (supernatant of human umbilical cord mesenchymal stem cells);low concentration group (0.25×105 human umbilical cord mesenchymal stem cells);moderate concentration group (1.0×105 human umbilical cord mesenchymal stem cells);high concentration group (4.0×105 human umbilical cord mesenchymal stem cells). Each rat was injected 0.8 mL liquid in muscle, 0.2 mL in each limb, twice at weeks 1 and 4. Biochemical tests were conducted before and after injection. At the end of 8 weeks, al the rats were kil ed and hematoxylin-eosin staining was done with the liver, spleen, lung, kidney, brain and muscle.
RESULTS AND CONCLUSION:There was no abnormal change about biochemical tests and hematoxylin-eosin staining after the intramuscular injection of heterogeneous umbilical cord mesenchymal stem cells. No significant alteration was observed in the liver, spleen, lung, kidney, brain, and muscle of the limb after the injection of heterogeneous umbilical cord mesenchymal stem cells under suitable concentration. These findings indicate intramuscular injection of heterogeneous umbilical cord mesenchymal stem cells at certain concentrations is safe and reliable.

Objective To analyze of internal strength in patients with chronic disease,make clear the concept development,property,prerequisites,outcome and evaluation index of internal force.Methods To retrieve the relevant research literature in the knowledge service platform of Pubmed,PsycINFO and Chinese CNKI,Wanfang data,using the Rodgers analysis method to analyze the evolution of the concept of internal force.Results The molding process of internal strength of patients with chronic diseases included 4 defining characteristics:self concept,support,development and transcendence.Conclusions Rodgers evolution concept analysis method can help medical workers make clear concept essence of internal strength,deepening their cognition and understanding,so as to provide the basis for the implementation of the related research and clinical interventions.

BACKGROUND:It is unclear whether intramuscular injection of human umbilical cord mesenchymal stem cells wil increase regeneration of normal myocardial cells and play adverse effects on normal myocardium. OBJECTIVE:To observe the effects of intramuscular injection of human umbilical cord mesenchymal stem cells on expression of the myocardial ki-67, phh3 and cTnT in normal Wistar rats. METHODS:A total of 60 male Wistar rats were divided into six groups randomly:normal group, solution group, supernatant group, low concentration group, moderate concentration group, and high concentration group. These groups were intramuscularly injected different liquid, respectively, as fol ows:PBS, DMEM, the supernatant of human umbilical cord mesenchymal stem cells, human umbilical cord mesenchymal stem cells with amount of 0.25×105, human umbilical cord mesenchymal stem cells with amount of 1.0×105, human umbilical cord mesenchymal stem cells with amount of 4.0×105 . After 4 weeks, each rats received the second same intramuscular injections of human umbilical cord mesenchymal stem cells. Four weeks after the second injection, al rates were kil ed to obtain myocardial tissues which were fixed, embedded and sectioned. Final y, the ki-67, phh3 and cTnT expressions of the myocardium were detected by immunohistochemical technique. RESULTS AND CONCLUSION:In the normal group, negative expression of the ki-67 was observed in the caryon of myocardial cells, weak positive expression of the phh3 was observed in the caryon of myocardial cells, and positive expression of the cTnT was observed in the caryon of myocardial cells. Compared with the normal group, the expression of the ki-67, phh3 and cTnT in the myocardium had no significant difference among the other groups (F=1.076, 0.167, 0.300;P>0.05). Human umbilical cord mesenchymal stem cells or the supernatant of human umbilical cord mesenchymal stem cells via intramuscular injection have no effects on the expression of the ki-67, phh3 and cTnT in normal Wistar rats.

Objective To study the impact of vegetation changes on the distribution of Oncomelania hupensis in the marshland and lake regions.MethodsA bottomland from the 14 bottomlands along the Qiupu River in the Guichi District,Chizhou City,Anhui Province was selected,and a 50 m?50 m area of uniform vegetation was choosed as the research field.Low-grass group,boundary-grass group,hay group and control group were designed to represent four types of vegetation's status and the snail density,soil temperature and soil moisture were surveyed half a month after the design.The change of Oncomelania hupensis's distribution due to the vegetation change was analyzed statistically.ResultsThe snail density of the hay group was nearly 0 with high soil moisture and low soil temperature.The snail density of the low-grass group was obviously decreased(32.1/0.1 m2),and the snail density of the boundary group slightly increased,which had no statistical significance compared with the snail density of the control group.ConclusionsOncomelania hupensis moves from the low-grass group to the boundary group after the vegetation is cut down,which changes the distribution of snail.Hay group is the worst environment for Oncomelania hupensis to survive and the method of cut-overlay grass may be used to improve the effect of molluscicide.