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21.
类固醇类激素联合携带Fas基因重组腺病毒治疗瘢痕疙瘩的体内实验研究 总被引:1,自引:0,他引:1
目的应用成功制备的携带人Fas基因的两种重组腺病毒,联合类固醇激素进行瘢痕疙瘩的动物实验研究,判断携带人Fas基因的重组腺病毒与类固醇激素联合治疗瘢痕疙瘩的效果。方法构建瘢痕疙瘩裸鼠模型。使用Ad-Fas(B),Ad-Fas(T)两种构建成功的腺病毒注射及其它辅助治疗手段,实施针对植入裸鼠皮下的瘢痕疙瘩组织的体内治疗方案。通过大体观察,常规病理及电镜观察检测瘢痕疙瘩组织块的变化。结果①单纯使用腺病毒注射后的瘢痕疙瘩组织块体积仅轻度缩小。②前期注射Ad-Fas(B)或Ad-Fas(T)后,使用类固醇激素作为后续治疗因素,其瘢痕疙瘩组织块均明显缩小。③使用腺病毒治疗后,能有效地减少曲安缩松的使用,从而减轻类固醇类激素治疗的副作用。结论①裸鼠为免疫缺陷动物,所以该结果并不能否认病毒的直接治疗作用,在免疫性动物体内直接注射腺病毒的治疗效果尚无结论。②重组腺病毒Ad-Fas(B)及Ad-Fas(T)的瘢痕疙瘩基因治疗的动物实验为瘢痕疙瘩的治疗展示了一条全新的途径。 相似文献
22.
Sertoli细胞诱导大鼠肝内胰岛移植物免疫豁免的实验研究 总被引:5,自引:3,他引:2
目的 探究睾丸Sertoli细胞能否对肝内共移植的胰岛移植物提供免疫豁免作用以及共移植的睾丸Sertoli细胞最佳数量。方法将同种大鼠胰岛及不同数量的睾丸Sertoli细胞同时移植于糖尿病受体的肝内,观察移植物存活情况、胰岛功能、并检测移植物内胰岛素和Fas配体(FasL)表达以及浸润淋巴细胞凋亡情况。结果单纯胰岛移植组平均存活期为(5.6±0.8)d,同时与胰岛细胞在肝内共移植的睾丸细胞数增加至1×107个时,平均存活期为(41.4±4.61)d,明显延长(P<0.05),胰岛移植物中有大量表达FasL的睾丸细胞和表达胰岛素的胰岛细胞.在移植物周围有大量浸润的淋巴细胞凋亡。结论睾丸Sertoli细胞与胰岛细胞同时在肝内共移植,通过诱导局部豁免而延长胰岛移植物的存活时间,且同时共移植1×107个Sertoli细胞时效果最好。 相似文献
23.
大鼠高胆红素血症与海马神经细胞凋亡关系的实验研究 总被引:1,自引:0,他引:1
目的探讨高胆红素血症新生大鼠海马区Fas蛋白、N-甲基-D-天冬氨酸(NMDA)受体的表达、神经细胞凋亡率及其相关性,以进一步阐明胆红素的神经毒性机制。方法通过制作高胆红素血症动物模型,采用免疫组化法、TUNEL法及流式细胞术检测大鼠海马区Fas蛋白、NMDA受体的表达率及神经细胞的凋亡率,并探讨其问相关性。结果高胆红素血症时,海马区神经组织,Fas蛋白、NMDA受体表达率及神经细胞凋亡率明显增高,且与脑组织胆红素浓度呈正相关。结论高胆红素血症时,胆红索可通过NMDA受体过度活化和Fas系统的参与,传递凋亡信号,介导胆红素神经毒性的发生,导致神经细胞凋亡。 相似文献
24.
131I对甲状腺细胞凋亡的影响 总被引:1,自引:0,他引:1
由于每个患者特异性基因决定的个体辐射敏感性不同,使得每个接受131I治疗的患者对治疗的反应不一,因而疗效差异较大.针对不同的个体,采用不同的剂量治疗才可以提高131I治疗的效率,降低甲状腺功能减退症的发病率.通过目前的分子生物学技术,我们已经了解到一些基因的蛋白表达产物(Fas/FasL、Bcl-2等)与细胞凋亡和射线诱导凋亡的联系,使对凋亡基因表达产物的体外监测成为可能.也许通过对这些指标的监测,可以使我们在131I治疗过程中实现对不同的个体给予恰当的个体剂量. 相似文献
25.
Homeostasisof11ematopoiesisiscontrollednotoillybytheproliferationanddifferentiationofcells,butalsobycelldeath.Inadditiontolossofcontrolofcellproliferation,disruptionofapoptosis--inducedf[lnctionalsocontributestotumordevelopment.Althoughdiversesignalscaninduceapoptosisinawidevarietyofcelltypes,anumberofevolutionarilyconservedgenesregulateafinalcommoncelldeathpathway,thatisconservedinmanyspeciesfromwormstohumansll].Thehcf--2proto--oncogeneisoneofthecrucialapoptosisantagonizinggenes.Highlevelofhc… 相似文献
26.
Epithelial junctions play crucial roles during metazoan evolution and development by facilitating tissue formation, maintenance, and function. Little is known about the role of distinct types of junctions in controlling epithelial transformations leading to invasion of neighboring tissues. Discovering the key junction complexes that control these processes and how they function may also provide mechanistic insight into carcinoma cell invasion. Here, using the Drosophila ovary as a model, we show that four proteins of the basolateral junction (BLJ), Fasciclin-2, Neuroglian, Discs-large, and Lethal-giant-larvae, but not proteins of other epithelial junctions, directly suppress epithelial tumorigenesis and invasion. Remarkably, the expression pattern of Fasciclin-2 predicts which cells will invade. We compared the apicobasal polarity of BLJ tumor cells to border cells (BCs), an epithelium-derived cluster that normally migrates during mid-oogenesis. Both tumor cells and BCs differentiate a lateralized membrane pattern that is necessary but not sufficient for invasion. Independent of lateralization, derepression of motility pathways is also necessary, as indicated by a strong linear correlation between faster BC migration and an increased incidence of tumor invasion. However, without membrane lateralization, derepression of motility pathways is also not sufficient for invasion. Our results demonstrate that spatiotemporal patterns of basolateral junction activity directly suppress epithelial invasion by organizing the cooperative activity of distinct polarity and motility pathways. 相似文献
27.
Immunolocalization of Fas and Fas ligand in the ovaries of women with polycystic ovary syndrome: relationship to apoptosis 总被引:6,自引:0,他引:6
Cataldo NA Dumesic DA Goldsmith PC Jaffe RB 《Human reproduction (Oxford, England)》2000,15(9):1889-1897
Both Fas (APO-1, CD95), an apoptosis-inducing receptor, and its ligand, Fas ligand (FasL, CD95L), have been localized to the ovary. Granulosa cell apoptosis occurs in antral follicular atresia. In polycystic ovary syndrome (PCOS), antral follicles accumulate with some atretic features. The ovarian expression of Fas and FasL was examined in PCOS by immunohistochemistry and correlated with immunodetection of apoptotic cells. Fas immunostaining was present in pre-antral follicle oocytes, some primary and secondary pre-antral follicle granulosa cells, and both granulosa and theca of antral follicles. Thecal staining persisted with advancing atresia, while granulosa staining declined. In antral follicles, abundant Fas-positive cells co-localized with scattered nuclei immunopositive for apoptosis. Ovarian vascular myocytes were strongly Fas-immunopositive. FasL immunostaining was present in pre-antral follicles in oocytes and variably in granulosa. In antral follicles, granulosa and thecal FasL staining increased with advancing atresia. Normal control ovaries showed follicular Fas and FasL staining patterns similar to those in PCOS, but vascular staining was less prominent. In one healthy follicle, Fas immunostaining was seen in the oocyte and weakly in mural granulosa and theca interna. The results suggest that in PCOS, an alteration in Fas-mediated apoptosis, does not cause abnormal folliculogenesis, but may promote ovarian vascular remodelling. 相似文献
28.
Kim HS Lee SH Lee JW Soung YH Lee JH Park JY Cho YG Kim CJ Kim SY Lee YS Park WS Kim SH Lee JY Yoo NJ 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(4):490-491
Among the systems triggering apoptosis, the Fas-Fas ligand (FasL) system is recognized as a major pathway for the induction of apoptosis in cells and tissues. Ligation of Fas by either an agonistic antibody or FasL transmits a 'death signal' to the target cell, potentially triggering apoptosis. Alterations of genes along the Fas-mediated apoptosis pathway have been reported in many human cancers. However, there have been no data regarding FasL gene mutations in human cancers. We hypothesized that FasL gene mutation might be involved in the development of non-Hodgkin lymphoma (NHL). In this study, we analyzed the entire coding region of the FasL gene for the detection of somatic mutations in a series of 111 NHLs and found that one tumor had a FasL gene mutation in the cytoplasmic domain. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant in 293T cells, but couldn't find any significant loss of cell death compared to the wild-type FasL. Together, these data suggest that FasL is occasionally mutated in human NHL and that FasL mutations appear to play no role in the pathogenesis of the vast majority of NHLs. 相似文献
29.
Enhanced expression of Fas-associated proteins in decidual and trophoblastic tissues in pregnancy-induced hypertension 总被引:2,自引:0,他引:2
Koenig JM Chegini N 《American journal of reproductive immunology (New York, N.Y. : 1989)》2000,44(6):347-349
PROBLEM: To determine if feto-placental tissues from gestations complicated by pregnancy-induced hypertension (PIH) have altered expression of Fas-associated proteins. METHOD OF STUDY: The expression of several Fas-related proteins was determined in fetal membranes, decidua, and placentas obtained from PIH-affected (n = 12, age range 32-36 weeks) and normal (n = 6, age range 37-41 weeks) gestations. Paraffin-embedded tissue sections were stained with specific monoclonal antibodies to Fas, Fas ligand (FasL), caspase-3, and bax. RESULTS: We observed greater expression of Fas and FasL in amnion and decidua from PIH-affected gestations than in normal controls. Intense staining was observed only in the perivascular endothelium (caspase-3) and in decidual cells (bax) from PIH gestations. CONCLUSION: Differential expression of Fas-related proteins in fetal membranes, decidua, and placentas from PIH-affected gestations is consistent with increased apoptosis, and suggests activation of the Fas/FasL pathway in a tissue-specific manner. 相似文献
30.