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排序方式: 共有93条查询结果,搜索用时 31 毫秒
1.
外源性Ⅰ型胶原对人胚骨膜成骨细胞生物学特性的影响   总被引:16,自引:1,他引:15  
OBJECTIVE: To study the influence of type I collagen (COL I) on the cell behavior of human periosteous osteoblasts (OB) and the application of type I collagen in constructing bioactive artifical bone. METHODS: OB were cultured on dishes coated with bovine type I collagen in different final concentrations. The cell adhesion was examined by the methods of cell count, the proliferation of OB was studied by 3H-TdR, and the osteoblastic ability was assessed by the synthesis of collagen, osteocalcin and alkaline phosphatase (ALP). RESULTS: OB cultured on type I collagen layer had the following characteristics: 1. The amounts of adhesive cells were maximal top in 25 micrograms/ml final concentration; 2. The proliferation of OB was decreased above 12.5 micrograms/ml final concentration (P < 0.05); 3. The synthesis of type I collagen was reduced slightly (above 25 micrograms/ml, P < 0.05); 4. The secretion of osteocalcin was increased markedly (above 6.25 micrograms/ml, P < 0.05, which reached maximally in 25 micrograms/ml); 5. The ALP activity was also increased (above 12.5 micrograms/ml, P < 0.05). CONCLUSION: Type I collagen promotes the expression of osteoblastic phenotype and cell adhesion. When the scaffold materials for bone tissue engineering are coated with type I collagen, the osteogenesis of OB is enhanced to accelerate the transformation course from artificial bone to biological bone, the best final concentration is 25 micrograms/ml.  相似文献
2.
Objective To evaluate the efficacy of hepatitis B immune globulin (HBIG) in preventing intrauterine infection by hepatitis B virus (HBV) and to investigate its mechanism. Methods Forty-eight pregnant women positive for hepatitis B surface antigen (HBsAg) were randomly divided into 2 groups. The 34 women in the study group were injected with HBIG during pregnancy; the other 14 women were controls. Maternal blood samples were taken before HBIG injection and at delivery. Neonatal blood samples were taken within 24 hours after birth before HBIG and hepatitis B vaccine were given. HBsAg and antibody to HBsAg (anti-HBs) were tested by radioimmunoassay. Results None of the 35 newborns (including 2 twins) in the study group was positive for HBsAg, but 3 (21%) in the control group were positive (P=0.02). The HBsAg titers in the women in the study group decreased after HBIG injection. Of the 35 newborns in the study group, 32 (91%) were positive for anti-HBs. Conclusion Systematic injections of HBIG during pregnancy may prevent intrauterine HBV infection, the mechanism of which may be reduction of maternal HBV viremia and production of fetal passive immunity.  相似文献
3.
Ⅰ型胶原—整合素α2β1系统对成骨细胞生物学特性的调控   总被引:13,自引:1,他引:12  
为进一步探讨Ⅰ型胶原及其受体系统是否为成骨细胞功能活动所必需,使用Ⅰ型胶原和整合素α2β1的一抗阻断Ⅰ型胶原-整合素α2β1系统,以细胞计数法比较成骨细胞的增殖能力,流式细胞仪分析成骨细胞的凋亡情况,RT-PCR技术研究Ⅰ型胶原、整合素α2β1及骨钙素的mRNA表达情况。结果发现阻断Ⅰ型胶原-整合素α2β1系统后,成骨细胞的增殖能力减弱,凋亡率增高,Ⅰ型胶原、整合素α2β1及骨钙素的mRNA表达减  相似文献
4.
血管内皮细胞生长因子与高原肺水肿发病的关系   总被引:11,自引:1,他引:10  
目的 探讨血管内皮细胞生长因子(VEGF)表达变化在高原肺水肿发病、高原习服-适应中的意义。方法 培养大鼠肺动脉血管内皮细胞,采用RT-PCR方法和酶联免疫吸附(ELISA)方法分别观察低氧(体积分数为1%的O2)细胞及培养液中VEGF表达变化;将大鼠分为5组,分别模拟不同海拔高度、不同时间进行间断低氧习服,每天4h,间断低氧习服后的大鼠再进行急性低氧(8000m,4h)。用免疫组织化学及RNA狭缝杂交方法测定急性低氧和低氧习服不同时间、不同海拔高度大鼠肺组织VEGF变化,并对肺组织切片进行初步病理分析;采用ELLSA方法测定大鼠、高原移居者及高原肺水肿患者治疗前后血浆中VEGF水平。结果 低氧时大鼠肺动脉血管内皮细胞VEGF表达水平明显升高(P〉0.01);低氧大鼠(包括急性低氧组及间断低氧习服组)血头及肺组  相似文献
5.
弹力酶诱发动脉瘤模型   总被引:10,自引:0,他引:10  
目的:以猪胰弹性蛋白酶腐蚀动脉壁结构,建立动脉瘤模型,以期获得形态和病理均与临床颅内动脉瘤相似的模型。方法:选用新西兰大白兔,将猪胰弹性蛋白酶处理过的兔一侧颈动脉段移植到对侧正常动脉侧壁形态动脉瘤模型。在2周-1个月内对动脉瘤模型进行复查,并行病理学检查。结果:移植酶处理的动脉段形成的动脉瘤模型在1个月内保持稳定或略有增大,动脉瘤壁呈紫红色,容易破裂,弹力板缺失,只由薄层的结缔组织构成。结论:移植酶处理的动脉段形成的动脉瘤模型手术操作简单,重复性好,模型稳定,具有良好的形态和病理特征,有望取代流行的静脉移植动脉瘤模型。  相似文献
6.
输精管结扎对大鼠睾丸生精细胞凋亡的影响   总被引:8,自引:1,他引:7  
为探讨输精管结扎对睾丸曲精管生精细胞凋亡程度的影响,应用流式细胞仪和脱氧核糖核酸末端转移酶介导的dUTP缺口末端标记技术,检测大鼠输精管结扎和假手术后2-12周睾丸生精细胞的凋亡情况。  相似文献
7.
目的了解引起我国莱姆病的伯氏疏螺旋体外膜蛋白C(OspC)基因变异情况。方法应用聚合酶链反应从2株莱姆病螺旋体中国分离株BT01和BJ-9011全基因组DNA中将OspC基因调出,并插入质粒pGEM-3ZF(+)中,构建重组质粒pGEM-3ZF(+)-OspC,经Sanger双脱氧末端终止法测序,并将之与国外其它分离株进行同源性比较。结果除信号肽序列外,2株莱姆病螺旋体分离株BT01和BJ-9011的OspC基因依次为579bp和576bp,分别编码193和192氨基酸,两者核苷酸和氨基酸序列的同源性分别为86%和83%,与国外分离株(PBi、PKo及B31)的同源性均较高,其中BJ-9011株与国际标准株B31株之间核苷酸及氨基酸同源性达99%。结论伯氏疏螺旋体Os-pC基因在国内2个分离株之间存在一定差异,其与国外分离株之间也存在一定差异  相似文献
8.
上海近代中医教育概述   总被引:8,自引:0,他引:8  
简要介绍自鸦片战争后至1948年上海的中医办学情况。重点记述了上海中医专门学校、中国医学院、上海国医学院、新中国医学院等4所私立中医学校的创办经过和办学特点。同时还介绍了近代上海中医函授教育的情况。  相似文献
9.
ProtectiveefectofrecombinanthumanaugmenterofliverregenerationonCCl4inducedhepatitisinmiceYangXiaoming杨晓明,WangAimin王爱民,ZhouPi...  相似文献
10.
Cadmium(Cd),one of the most dangerous heavy metals,has a very similar ionic radius to calcium(Ca),The interference of cadmium in calcium homeostasis may play an important role in cadmium toxicity.Recent reports indicate that calmodulin(CaM) inhibitors such as trifluoperazine and chlorpromazine(CPZ) could protect rodents against cadmium toxicity,It was also reported that pretreatment of mice with zine(Zn)could reduce the adverse effects induced by cadmium.The aim of this study is to determine whether Cd changes the balance of other essential metals such as Zn and copper(Cu) in rat tissues,and whether CPZ can reverse these changes which are induced by cadmium intoxication.Adult male Sprague-Dawley(SD) rats were injected intraperitoneally(ip) with cadmium chloride(CdCl2)(0.2,0.4,0.8mg Cd/kg body wight) alone and 0.4mg Cd/kg in association with CPZ(5mg/kg) daily for a week.The control animals were injected with normal saline only.The results showed that the cadmium content in the liver,kidney,and testis increased significantly with a dose-response relationship.Cadmium treatment markedly increased the Zn and Ca content in some of the tissues,Hepatic and renal metallothionein(MT) increased significantly after cadmium intoxication,CPZ treatment,howerver,reduced cadmium content in liver,but not blood and kidney.CPZ seemed to decrease the content of MT in liver and significantly increase the amounts of MT in kidney.These data suggest that the intervention of cadmium with tissue essential metals may play a role in cadium toxicity in rats,and calmodulin inhibitors to some extent can reduce the adverse effect of cadmium by decreasing the cadmium load in tissues and reversing the unbalance of essetial metals.  相似文献
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