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排序方式: 共有370条查询结果,搜索用时 15 毫秒
1.
目的:研究严重烫伤后血IL-6和IL-1α对中性粒细胞(PMN)凋亡的影响。方法:复制30%体表面积Ⅲ度烫伤大鼠模型;分离PMN,TUNEL荧光标记,流式细胞仪分析细胞凋亡;PMNcaspase3活性以荧光免疫吸附酶法测定;血清IL-6和IL-1α水平以酶联免疫法测定。结果:血清IL-6水平(μg/L)在伤后各组(3、6、12、24、48h依次分别为9.14±1.16、12.49±1.14、3.01±0.75、1.41±0.28和1.56±0.43)和IL-1α水平(ng/L)在伤后3、6、12h组(90.08±8.39、320.93±14.48和47.84±5.19)均分别显著高于伤前对照组IL-6(0.24±0.07)和IL-1α(27.65±4.86)水平(P<0.05);伤后各组PMN凋亡率(%)按时点依次为9.89±2.00、4.98±1.35、1.31±0.72、2.49±1.87和6.88±1.13显著少于伤前组13.66±3.88(P<0.05);PMNcaspase-3的活性测定结果与PMN的凋亡表现相一致。结论:大鼠烫伤后外周血PMN凋亡明显延迟;IL-6和IL-1α等细胞因子是重要的影响因素,减少细胞内caspase-3的激活可能是其机制之一。  相似文献   
2.
Regulated cell death (RCD) triggered by innate immune activation is an important strategy for host survival during pathogen invasion and perturbations of cellular homeostasis. There are two main categories of RCD, including nonlytic and lytic pathways. Apoptosis is the most well-characterized nonlytic RCD, and the inflammatory pyroptosis and necroptosis pathways are among the best known lytic forms. While these were historically viewed as independent RCD pathways, extensive evidence of cross-talk among their molecular components created a knowledge gap in our mechanistic understanding of RCD and innate immune pathway components, which led to the identification of PANoptosis. PANoptosis is a unique innate immune inflammatory RCD pathway that is regulated by PANoptosome complexes upon sensing pathogens, pathogen-associated molecular patterns (PAMPs), damage-associated molecular patterns (DAMPs) or the cytokines produced downstream. Cytosolic innate immune sensors and regulators, such as ZBP1, AIM2 and RIPK1, promote the assembly of PANoptosomes to drive PANoptosis. In this review, we discuss the molecular components of the known PANoptosomes and highlight the mechanisms of PANoptosome assembly, activation and regulation identified to date. We also discuss how PANoptosomes and mutations in PANoptosome components are linked to diseases. Given the impact of RCD, and PANoptosis specifically, across the disease spectrum, improved understanding of PANoptosomes and their regulation will be critical for identifying new therapeutic targets and strategies.  相似文献   
3.
溴氰菊酯对大鼠脑神经细胞凋亡及Caspase-3表达的影响   总被引:3,自引:2,他引:3  
目的 研究Caspase-3在溴氰菊酯(deltamethrin,DM)诱导大鼠脑神经细胞凋亡机制中的作用。方法 成年雄性Wistar大鼠腹腔注射12.5 mg/kg的DM染毒,并分成不同时间观察组;以FACS420型流式细胞仪测定大鼠海马和皮层细胞凋亡率和Caspase-3蛋白的表达;以四肽化合物Ac-DEVD-pNa为底物测其神经细胞Caspase-3活力。结果 DM染毒后24 h、48 h、5 d组大鼠海马、皮层神经细胞凋亡率[海马:(8.45±1.02)%、(9.44±1.14)%、(7.58±0.75)%,皮层:(7.90±0.49)%、(8.01±0.87)%、(7.97±0.41)%]均高于对照组[海马:(2.97±0.36)%,皮层:(3.50±0.48)%],差异有统计学意义(P<0.01),而5 h组未见明显变化;DM染毒后5、24、48 h,大鼠海马、皮层神经细胞Caspase-3活力(A405nm吸光度值,海马:0.389±0.038、0.472±0.041、0.295±0.049,皮层:0.321±0.068、0.429±0.077、0.344±0.047)与5 d组大鼠海马Caspase-3活力(0.246±0.065)均明显高于对照组(海马:0.184±0.054,皮层:0.198±0.049),差异有统计学意义(P<0.05,P<0.01);DM染毒后5、24、48h,大鼠脑组织Caspase-3蛋白表达亦明显高于对照组,5 d组未见明显变化。结论DM可影响大鼠脑海马和皮层神经细胞凋亡率、Caspase-3活力及蛋白表达;Caspase-3活力及蛋白表达升高发生在神经细胞  相似文献   
4.
Abstract

Introduction: Fractional CO2-laser is considered a preferential method for skin resurfacing, but little is known about the molecular mechanisms underlying this surgical tool. In the present study, we investigated the possible role of apoptosis by the sequential analysis of lesional skin after laser treatment, with special attention to power. Moreover, we have analyzed if there is a correlation with clinical improvement. Materials and methods: We evaluated the effects of fractional CO2-laser in twelve patients with photodamage skin Fitzpatrick types I to III. Apoptosis markers were assessed by an immunohistochemical study on skin samples of foream at 24 h, 72 h and 7 days after the irradiation with 15 W or 20 W. Moreover, clinical improvement was assessed by iconography. Results: Fractional CO2-laser induced an inflammatory repair process mediated by activation of apoptotic pathway that was completed in 7 days. The expression of proapototic markers, as annexin-VII and Caspases-9 was increased 24–72 hours after irradiation and decreased after 7 days. While the expression of the anti-apototic marker Bcl-2 increased progressively during 7 days after treatment. Conclusion: Our study suggests that the skin's appearance may be enhanced by creating skin changes through apoptosis. Apoptosis, one of the major mechanisms of cell death, might play a key role in initiating the paracrine cascades that lead to cell proliferation.  相似文献   
5.
目的 研究中草药缬草提取物缬草波春联合Caspases抑制剂诱导MKN45胃癌细胞凋亡的作用。方法 将MKN45胃癌细胞分成4组:第1组加入同体积的生理盐水为对照;第2组分别加入浓度为10μM的Caspases-3、-8、-9抑制剂;第3组加入浓度为100 mg/L的缬草波春;第4组加入浓度为10 μM的Caspases-3、-8、-9抑制剂+浓度为100 mg/L的缬草波春混合物。药物作用24小时、48小时、72小时后,用流式细胞计分别检测凋亡率。结果 24、48、72小时作用后,第2组诱导MKN45细胞的凋亡率与对照组相似(P>0.05);第3组诱导MKN45细胞的凋亡率明显高于照组相(P<0.01);第4组中缬革波春联合Caspases-3、-9抑制剂诱导MKN45细胞的凋亡率均与对照组相似(P>0.05);缬草波存与Caspases-8抑制剂联合应用组诱导MKN45细胞的凋亡率明显高于对照组比(P<0.01),与第2组相似(P>0.05)。结论 缬草波春能诱导MKN45胃癌细胞凋亡,诱导凋亡能被Caspases-3、-9抑制剂抑制,Casoases-8抑制剂对缬草波春诱导的调亡无影响。  相似文献   
6.
The aim of the present study was to analyze participation of apoptosis and proliferation in gonadal development in the chicken embryo by: (1) localization of apoptotic (TUNEL) and proliferating (PCNA immunoassay) cells in male and female gonads and (2) examination of mRNA expression (RT-PCR) of caspase-3, caspase-6 and Bcl-2 in the ovary and testis during the second half of embryogenesis and in newly hatched chickens. Apoptotic cells were found in gonads of both sexes. At E18 the percentage of apoptotic cells (the apoptotic index, AI) in the ovarian medulla and the testis was lower (p < 0.05) than in the ovarian cortex. In the ovarian medulla, the AI at E18 was lower (p < 0.05) than on E12. In the testis, the AI was significantly lower (p < 0.05) at E18 than at E15 and 1D. The percentage of proliferating cells (the proliferation index: PI) within the ovary significantly increased from E15 to 1D in the cortex, while proliferating cells in the medulla were detected only at E15. In the testis, the PI gradually increased from E12 to 1D. The mRNA expression of caspase-3 and -6 as well as Bcl-2 was detected in male and female gonads at days 12 (E12), 15 (E15) and 18 (E18) of embryogenesis and the day after hatching (1D). The expression of all analyzed genes on E12 was significantly higher (p < 0.05) in female than in male gonads. This difference was also observed at E15 and E18, but only for the caspase-6. The results obtained showed tissue- and sex-dependent differences in the number of apoptotic and proliferating cells as well as mRNA expression of caspase-3, -6 and Bcl-2 genes in the gonads of chicken embryos. Significant increase in the number of proliferating cells in the ovarian cortex and lack of these cells in the ovarian medulla (stages E12, E18, 1D) simultaneous with decrease in the intensity of apoptosis only in the medulla indicates that proliferation is the dominant process involved in the cortical development, which constitutes the majority of the functional structure of the fully developed ovary. No pronounced changes in the expression of apoptosis-related genes found during embryogenesis suggest that they cannot be considered as important indicators of gonad development. The molecular mechanisms of the regulation of balance between apoptosis and proliferation in developing avian gonads need to be further investigated.  相似文献   
7.
AIMS: The induction of tumour cell death by apoptosis is a major goal of cancer therapy and the in situ detection of apoptosis in tumour tissue has become an important diagnostic parameter. Different apoptosis detection methods assess distinct biochemical processes in the dying cell. Thus, their direct comparison is mandatory to evaluate their diagnostic value. The aim of this study was to compare the immunohistochemical detection of active caspase 3 and single-stranded DNA in primary and metastatic liver tumours as markers of apoptotic cell death. METHODS: We studied detection of active caspase 3 and single-stranded DNA in 20 primary hepatocellular carcinomas (HCC) and 20 liver metastases from colorectal carcinomas (CRC) using immunohistochemistry on paraffin sections. RESULTS: Our results reveal that both methods are suitable and sensitive techniques for the in situ detection of apoptosis, however, they also demonstrate that immunohistochemistry for active caspase 3 and single-stranded DNA have differential sensitivities in HCC and CRC. CONCLUSION: The sensitivity of apoptosis detection using immunohistochemistry for active caspase 3 and single-stranded DNA may be tumour cell type dependent.  相似文献   
8.
Aspartame is an artificial sweetner added to many low-calorie foods. The safety of aspartame remains controversial even though there are many studies on its risks. In this study, to understand the physiological effects of trace amounts of artificial sweetners on cells, the effects of aspartame on apoptosis were investigated using a PC12 cell system. In addition, the mechanism of apoptosis induced by aspartame in PC12 cells and effects on apoptotic factors such as cytochrome c, apoptosis-inducing factor, and caspase family proteins were studied by Western blotting and RT-PCR.Aspartame-induced apoptosis in PC12 cells in a dose-dependent manner. In addition, aspartame exposure increased the expressions of caspases 8 and 9, and cytochrome c. These results indicate that aspartame induces apoptosis mainly via mitochondrial pathway involved in apoptosis due to oxigen toxicity.  相似文献   
9.
BackgroundThe present study aimed at optimization of the biotechnological production of the lignan justicidin B by genetically transformed cultures of Linum leonii and the pharmacological evaluation of the pro-apoptotic effects of the compound in HL-60 cells.MethodsA rapidly growing selected root line of L. leonii was grown in 2-L bioreactor for period of 40 days and the protocols for obtaining of the compound have been optimized. The pharmacological study included evaluation of the cytotoxicity of the compound in HL-60 cells (MTT-assay), its apoptogenic effects and its effects on caspase 3,8 and 9 activation.ResultsAfter 40 days of sterile run scale up of hairy root culture in bioreactor, 27.2 g/L dry weight of root biomass was harvested from the bioreactor culture vessel, recording about nine times increase over initial inoculum (3.0 g), with 1.55% ± 0.07 Justicidin B, greater than yields from 300 ml flasks. Our findings are the first work toward the scale up of L. leonii hairy roots-based biotechnological production of Justicidin B, employing bioreactors for high biomass production to meet the industrial requirement. The results from the pharmacological evaluation have shown that the tested arylnaphtalene lignan is a potent cytotoxic and proapoptotic agent against HL-60. The induction of apoptosis proceeds via activation of the intrinsic mitochondrial cell-death signaling pathways.ConclusionThe potent activity at low micromolar concentration and the feasibility of biotechnological production of justicidin B implies that there is enormous scope in its further evaluation as possible antineoplastic drug candidate.  相似文献   
10.
目的探讨丙戊酸钠(VPA)诱导乳腺癌细胞凋亡的作用。方法乳腺癌细胞株MCF-7细胞分为0.75~4.0 mmoL/L VPA实验组、对照组(不加VPA)及VPA与caspase抑制剂共同作用组。Annexin V-PI双染法流式细胞术检测细胞凋亡,间接免疫荧光法定量分析及分光光度法检测caspase- 3、caspase-8、caspase-9蛋白丰度和活性,探讨VPA诱导凋亡的机制,同时检测VPA与caspase-3、caspase- 8、caspase-9特异性抑制剂协同作用后细胞凋亡的变化来加以验证。结果各浓度VPA干预MCF-7细胞48 h后,细胞凋亡率显著增加,caspase-3、caspase-9活性升高、蛋白表达明显上调,与对照组相比有显著差异(F=552.1、610.9、312.8、222.8、70.3,均P〈0.001);而caspase-8活性及蛋白表达未见明显改变;1.5、3.0 mmol/L VPA与caspase-3、caspase-9相应特异性抑制剂共同作用组,细胞凋亡率均较VPA组显著降低(t=109.0、28.7、18.7、32.3,均P〈0.005);VPA与caspase-8特异性抑制剂共同作用组细胞凋亡率与VPA组比较无明显改变(t=1.03、2.32,均P〉0.05)。结论VPA可通过激活caspase-9介导的内源性凋亡途径,明显诱导乳腺癌细胞凋亡,具有较好的临床应用价值。  相似文献   
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