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991.
Guo M  Sato E  Jin A  Li X  Mori E  Xu Y  Mori T 《The Prostate》2002,51(3):166-174
BACKGROUND: We validated the induction of apoptosis in human prostate cancer PC3 cells by apoptosis-inducing nucleosides (AINs) released from the CD57(+)HLA-DR(bright)-natural suppressor (57.DR-NS) cell line. We analyzed the molecular signaling pathway during AINs-induced apoptosis in PC3 cells. METHODS: Direct and indirect co-cultures between 57.DR-NS and PC3 cells were performed. AINs were isolated by high-performance liquid chromatography (HPLC) from 57.DR-NS cell cultures. Apoptosis in PC3 cells was analyzed by DNA fragmentation, sub-G(1) DNA content with flow cytometry, and terminal deoxynucleotide transferase-mediated dUTP nick end-labeling (TUNEL) method. The DNA strand breaks and activation of caspase-3 in PC3 cells were measured by DNA unwinding and flow cytometry assay. RESULTS: The 57.DR-NS cell line generated apoptosis in PC3 cells via AINs. AINs isolated from 57.DR-NS cell cultures induced apoptosis in PC3 cells. Furthermore, we found DNA strand breaks followed by activation of caspase-3 during AINs-induced apoptosis in PC3 cells. CONCLUSIONS: The data obtained here indicated that AINs could induce apoptosis in PC3 cells through DNA strand breaks and activation of caspase-3.  相似文献   
992.
Siu SW  Lau KW  Tam PC  Shiu SY 《The Prostate》2002,52(2):106-122
BACKGROUND: Potential modulatory effects of melatonin on the proliferation of androgen-sensitive LNCaP and androgen-insensitive PC-3 and DU 145 prostate cancer cells were reported recently. In this study, we investigated the effects of combined melatonin and castration on LNCaP tumor growth in vivo, the interactions between melatonin and epidermal growth factor (EGF) on LNCaP cell proliferation, and melatonin actions on the proliferation of PC-3 and DU 145 cells. METHODS: Tumor development and growth in castrated nude mice inoculated with LNCaP cells or in intact animals inoculated with DU 145 cells, with or without daily melatonin treatment, were monitored by observation and caliper measurement. MT(1) receptor expression in native or transfected prostate cancer cell lines was examined by immunocytochemistry or 2-[(125)I]iodomelatonin binding. Cyclin D1 expression in LNCaP cells was assessed by Western blotting, and cell proliferation was measured by thymidine incorporation and/or cell count. RESULTS: Melatonin treatment was associated with further decreases in LNCaP tumor incidence and growth rate in castrated nude mice. Melatonin and 2-iodomelatonin (a melatonin receptor agonist) attenuated EGF-stimulated increases in LNCaP cell proliferation and cyclin D1 levels. Melatonin had no effect on the proliferation or growth of MT(1) receptor-expressing DU 145 cells, and of PC-3 cells in which MT(1) receptor protein was undetectable. The proliferation of transfected PC-3 cells expressing MT(1) receptor was unaffected by 2-iodomelatonin. CONCLUSION: Together with previous data, the present results indicate synergistic action of melatonin and castration in inhibiting the growth of androgen-sensitive LNCaP tumor. Androgen-sensitive prostate cancer cell proliferation may be modulated by opposite changes in cyclin D1 levels induced by activated MT(1) and EGF receptors. In androgen-insensitive prostate cancer cells, MT(1) receptor-mediated signal transduction may become defective not only through changes in membrane receptor protein expression and/or functions, but also by means of alterations in downstream postreceptor signaling events.  相似文献   
993.
体外药敏试验ATP-TCA与流式细胞仪在肝癌化疗中的应用   总被引:14,自引:0,他引:14  
目的 探讨体外化疗药敏试验系统(ATP-TCA系统)联合流式细胞仪(FCM)在肝癌化疗中的应用及其结果之间的关系。方法 取24例肝癌切除,活检或穿刺组织行体外药敏试验和流式细胞仪P170检测,并分析二者间的关系。结果 ATP-TCA的可评估率为91.67%;10种化疗药物的敏感率分别为:氟尿嘧啶5.00%,诺消灵5.00%,顺铂14.26%,足叶乙甙19.05%,草酸铂19.05%,丝裂霉素23.81%,表阿霉素28.57%,开普拓45.46%,健择47.62%,泰素63.64%;P170检测阳性率为57.14%;丝裂霉素,表阿霉素的敏感率在P170阴性表达时高,开普拓健择,泰素的敏感率高且在P170阳性表达和阴性表达时无显著差异。结论 ATP-TCA法联合FCM可较好用于肝癌化疗药物的筛选;丝裂霉素,表阿霉素可用于P170阴性表达的病人,开普拓,健择,泰素可用于P170阳性表达的病人。  相似文献   
994.
烫伤大鼠垂体前叶P物质和降钙素基因相关肽神经的变化   总被引:2,自引:0,他引:2  
目的 观察烫伤早期大鼠垂体前叶P物质 (SP)与降钙素基因相关肽 (CGRP)神经的形态分布变化。 方法 采用大鼠 30 %TBSAⅢ度烫伤模型 ,于伤后 1、2、6、10、12、2 4、72h 7个时相点 ,对垂体前叶SP和CGRP两种肽能神经行免疫组织化学染色观察 ;经图像分析测定 ,比较两种神经覆盖面积的变化。 结果 两种肽能神经的形态变化明显 ;伤后 1hSP、CGRP神经数目与对照相比分别增加 85 .7%和 6 0 .5 % ,神经纤维的膨体、分枝等明显增多 ;2h后减少 ,2 4h后趋于恢复。图像分析显示 :两种肽能神经的覆盖面积呈正相关变化 ,其基本变化趋势为伤后 1h升高 ,随后降低 ,伤后 12h降至最低点 ,然后回升。 结论 烫伤后早期大鼠垂体前叶的SP与CGRP神经形态分布发生明显变化 ,可能参与了全身应激反应的功能调节  相似文献   
995.
目的:探讨膀胱癌p53、p21^WAF1/CIP1和细胞周期素E(CyclinE)基因的表达、相互间的调控及其与膀胱肿瘤复发生为的关系。方法:采用免疫组织化学链霉菌抗生物素蛋白过氧化物酶法(SP)检测64例有随访资料的膀胱癌患者p53、p21^WAF1/CIP1、CyclinE基因和Ki-67抗原表达,并用双变量相关分析、Kaplan-Meier分析及Cox regression多因素分析。结果:p53与p21WAF1/CIP1之间有明显相关(rs=-0.630,P=0.000)。p21^WAF1/CIP1与CylinE之间无明显相关(rs=-0.160,P=0.206),p53、Ki-67阳性表达患者有较高的肿瘤复发率。结论:肿瘤的临床病理特征、p53、Ki-67可作为评估膀胱肿瘤恶性程度及预后的指标。  相似文献   
996.
目的 研究重组生长激素 (rhGH)在促进创面愈合过程中对烫伤大鼠肝、创面组织胰岛素样生长因子 Ⅰ (IGF Ⅰ ) /胰岛素样生长因子结合蛋白 3(IGFBP 3)mRNA表达的影响。方法制作大鼠深Ⅱ度烫伤模型 ,每日早上 9点皮下注射rhGH 0 .3IU/d ,疗程 1 0d。逆转录 聚合酶链反应 (RT PCR)检测肝、创面组织IGF Ⅰ /IGFBP 3mRNA表达 ;酶联免疫吸附试验 (ELISA)检测血IGF Ⅰ /IGFBP 3浓度 ;免疫组织化学检测Ⅰ、Ⅲ型胶原的表达。结果 用rhGH治疗 1 0d ,烫伤大鼠肝、创面组织IGF Ⅰ /IGFBP 3mRNA的表达、血IGF Ⅰ的水平较对照组明显升高 (P <0 .0 1 ) ;Ⅰ、Ⅲ型胶原的含量较对照组明显增多 (P <0 .0 1 ) ;而创面愈合时间平均提前 3d。结论 rhGH可通过增加肝、创面组织IGF Ⅰ /IGFBP 3mRNA的表达 ,促进创面愈合。  相似文献   
997.
目的:探讨野生型p53(wtp53)基因及其相关调控基因转录、翻译水平的变化与肠道干细胞分化的关系。方法:利用逆转录-多聚酶链反应(RT-PCR)和免疫组织化学技术,以细胞分化标志肝脂肪酸结合蛋白(L-Fabp)mRNA水平为动态参照,分别检测大鼠胚胎期E14d,E19d和幼鼠其E19d至成年大鼠,RT-PCR能够检测到小肠细胞内L-Fabp的mRNA,其中P2d,L-Fabp的mRNA含量最高,证实这两个期间为肠道干细胞高分化阶段。从胚胎到成年大鼠,小肠细胞p21mRNA及其蛋白表达均为阴性,p53mRNA水平无明显变化。然而从E14d-P2d,小肠上皮细胞p53蛋白信号呈逐渐增强趋势。P7d以后至成年期,p53蛋白信号为阴性。结论:在肠道干细胞迅速分化期,p53蛋白高表达可能是因为其半衰期延长,最终导致蛋白量累积的结果,而与转录水平无关,提示蛋白的稳定性对于p53调节肠道干细胞分化期基因的稳定性十分重要,另外,p53蛋白调节肠道干细胞的分化机制与p21途径无关。  相似文献   
998.
We present the case of a newborn male with D-transposition of the great arteries, ventricular septal defect, and subpulmonary stenosis who experienced two episodes of systemic-to-pulmonary artery shunt thrombosis. Hematologic evaluation revealed heterozygous factor V Leiden mutation. This report emphasizes the importance of evaluation for inherited coagulation disorders in pediatric patients with unexpected thrombotic complications.  相似文献   
999.
BACKGROUND: Historically the Fontan operation in patients with single ventricle heterotaxy syndrome and atrial isomerism has been associated with high mortality. We studied whether recent modifications of the surgical technique have improved outcome. METHODS: A retrospective review of 135 patients with heterotaxy syndrome who underwent a Fontan operation between 1981 and 2000 was performed. RESULTS: There were 93 patients with right isomerism and 42 with left isomerism. Anomalies of venous return included 25 patients with extracardiac pulmonary venous connection (19%) and 37 patients with an interrupted inferior vena cava (27%). Thirty-six patients (27%) had at least moderate atrioventricular valve regurgitation. The type of Fontan procedure included 17 patients with an atriopulmonary Fontan connection, 67 with a lateral tunnel modification, 19 with an intraatrial tube graft, 25 with an extracardiac tubegraft, and 7 with an intra-extra atrial tube graft. A fenestration was placed in 93 patients (78%). Early mortality was 19% before 1991, 3% since 1991, and no patient has died early since 1993. Ten-year survivals were 70% for Fontan operations before 1990 and 93% for Fontan operations after 1990. Thirty-two patients (23%) had prolonged pleural effusions. Risk factors for death included anomalous pulmonary venous connection (p = 0.02) and higher preoperative pulmonary vascular resistance (p = 0.002). Sixty-two patients (47%) had some form of early postoperative arrhythmia. At 10 years, freedom from late bradyarrhythmia and late tachyarrhythmia were 78% and 70%, respectively. Preoperative arrhythmias, older age at operation, and anatomic features were each independent predictors of late arrhythmia. CONCLUSIONS: The Fontan operation can now be performed in patients with heterotaxy syndrome with excellent survival. However, morbidity in terms of postoperative arrhythmias and prolonged pleural effusions remains significant. Fontan staging, appropriate choice of Fontan modification, aggressive treatment of concomitant malformations, and use of a baffle fenestration contribute to improved outcome.  相似文献   
1000.
Transforming growth factor-beta 1 (TGF-β1) is a cytokine member of the TGF-β superfamily involved in the control of proliferation and differentiation of various cell types. TGF-β1 plays an important role in bone formation and resorption. To determine the effect of TGF-β1 deficiency on bone mineral and matrix, tibias from mice in which TGF-β1 expression had been ablated (TGF-β1 null) were analyzed and compared with background- and age-matched wild-type (WT) control animals by Fourier transform-infrared imaging (FTIRI) and histochemistry. FTIRI allows the characterization of nondemineralized thin tissue sections at the ultrastructural level with a spatial resolution of 7 μm. The spectroscopic parameters calculated were: mineral-to-matrix ratio (previously shown to correspond to ash weight); mineral crystallinity (related to the crystallographically determined crystallite size and perfection in the apatite c-axis direction); and collagen maturity (related to the ratio of pyridinoline:deH-DHLNL collagen cross-links). Several fields were selected to represent different stages of bone development within the same specimen from the secondary ossification center to the distal diaphysis. Anatomically equivalent areas were compared as a function of age and genotype. The spectroscopic results were expressed both as color-coded images and as pixel population distributions for each of the three parameters monitored. Based on comparisons of histochemistry and FTIRI, there were distinctive age and genotype variations. At all ages examined, in the TGF-β1 null mice growth plates, alkaline phosphatase (ALP) activity and collagen maturity were reduced, but no effect on mineral content or crystallinity was noted. In the TGF-β1 null mice metaphyses, there was a persistence of trabeculae, but no significant alterations in mineral content or crystallinity. In contrast, mineral content, mineral crystallinity, and collagen maturity were reduced in the secondary ossification center and cortical bone of the TGF-β1 null mice. These results, consistent with a mechanism of impaired bone maturation in the TGF-β1 null mice, may be directly related to TGF-β1 deficiency and indirectly to increased expression of inflammatory cytokines in the TGFβ1 null mice.  相似文献   
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