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991.
Bone morphogenetic proteins (BMPs) play important roles in reproduction including primordial germ cell formation, follicular development, spermatogenesis, and FSH secretion. Dragon, a recently identified glycosylphosphatidylinositol-anchored member of the repulsive guidance molecule family, is also a BMP coreceptor. In the present study, we determined the tissue and cellular localization of Dragon in reproductive organs using immunohistochemistry and in situ hybridization. Among reproductive organs, Dragon was expressed in testis, epididymis, ovary, uterus, and pituitary. In the testis of early postnatal mice, Dragon was found in gonocytes and spermatogonia, whereas in immature testes, Dragon was only weakly expressed in spermatogonia. Interestingly, pregnant mare serum gonadotropin treatment of immature mice robustly induced Dragon production in spermatocytes. In adult testis, Dragon was found in spermatocytes and round spermatids. In the ovary, Dragon was detected exclusively within oocytes and primarily those within secondary follicles. In the pituitary, Dragon-expressing cells overlapped FSH-expressing cells. Dragon was also expressed in a number of cell lines originating from reproductive tissues including Ishikawa, Hela, LbetaT2, MCF-7, and JEG3 cells. Immunocytochemistry and gradient sucrose ultracentrifugation studies showed Dragon was localized in lipid rafts within the plasma membrane. In reproductive cell lines, Dragon expression enhanced signaling of exogenous BMP2 or BMP4. The present studies demonstrate that Dragon expression is dynamically regulated throughout the reproductive tract and that Dragon protein modulates BMP signaling in cells from reproductive tissues. The overlap between Dragon expression and the functional BMP signaling system suggests that Dragon may play a role in mammalian reproduction.  相似文献   
992.
To discover novel biomarkers of psoriasis, a target‐specific antibody array screening of serum samples from psoriasis patients was initially performed. The results revealed that vascular endothelial growth factor receptor 3 (VEGFR‐3) was significantly elevated in the sera of psoriasis patients, compared to healthy controls. Next, ELISA validation studies in a larger cohort of psoriasis patients (N = 73) were conducted, which confirmed that serum VEGFR‐3 was indeed significantly increased in patients with psoriasis compared to healthy controls (P < 0.001). Furthermore, receiver operating characteristic curve analysis demonstrated that serum VEGFR‐3 exhibited potential in distinguishing healthy controls from psoriasis patients: area under the curve = 0.85, P < 0.001. In addition, serum levels of VEGFR‐3 were correlated with Psoriasis Area Severity Index scores (R = 0.32, P = 0.008) in psoriasis patients. Interestingly, serum VEGFR‐3 levels were significantly elevated in psoriatic arthritis compared to non‐psoriatic arthritis (P = 0.026). A pilot longitudinal study demonstrated that serum levels of VEGFR‐3 could reflect disease progression in psoriasis. Collectively, serum VEGFR‐3 may have a clinical value in monitoring disease activity of psoriasis.  相似文献   
993.
目的 探讨在导乐陪伴分娩的过程中实施拉玛泽减痛分娩法对母乳分泌的影响.方法 将106例自然分娩的初产妇随机分为观察组52例和对照组54例,观察组在导乐陪伴分娩的基础上实施拉玛泽减痛分娩法;对照组仅按导乐陪伴分娩进行护理.观察2组产妇泌乳始动时间、泌乳量,采用t检验和χ2检验.结果 观察组比对照组泌乳始动时间提前,泌乳量增加.结论 在导乐陪伴分娩的过程中实施拉玛泽减痛分娩法能促进产后早泌乳,且泌乳量充足.  相似文献   
994.
Activation of p53 tumor suppressor by antagonizing its negative regulator murine double minute (MDM)2 has been considered an attractive strategy for cancer therapy and several classes of p53-MDM2 binding inhibitors have been developed. However, these compounds do not inhibit the p53-MDMX interaction, and their effectiveness can be compromised in tumors overexpressing MDMX. Here, we identify small molecules that potently block p53 binding with both MDM2 and MDMX by inhibitor-driven homo- and/or heterodimerization of MDM2 and MDMX proteins. Structural studies revealed that the inhibitors bind into and occlude the p53 pockets of MDM2 and MDMX by inducing the formation of dimeric protein complexes kept together by a dimeric small-molecule core. This mode of action effectively stabilized p53 and activated p53 signaling in cancer cells, leading to cell cycle arrest and apoptosis. Dual MDM2/MDMX antagonists restored p53 apoptotic activity in the presence of high levels of MDMX and may offer a more effective therapeutic modality for MDMX-overexpressing cancers.  相似文献   
995.
背景:不习惯强度的运动常导致运动性肌肉损伤,光生物调节治疗运动性肌肉损伤的研究存在不同的结果,且其治疗机制及其量效关系尚不清楚。 目的:总结和分析光生物调节作用的机制以及光生物调节疗法治疗运动性肌肉损伤时的剂量、强度、波长等与效应之间的关系。 方法:通过PubMed数据库(1996-01/2010-04)和中国学术期刊库(2000-01/2010-04)检索了低强度激光或单色光对运动性肌肉损伤的作用及其相关机制的文献,英文检索词为“low-level laser, phototherapy, exercise-induced muscle damage, delayed onset muscle soreness”,中文检索词为“低强度激光,光疗法,运动性肌肉损伤,延迟性肌肉酸痛”。手工补充检索低强度激光疗法的专著。共收集到中、英文文献38篇,排除重复及类似性研究,纳入31篇文献进行综述。 结果与结论:光生物调节作用的机制假说主要包括线粒体机制、一氧化氮机制、氧化还原机制和光生物信息模型理论,光生物调节疗法治疗运动性肌肉损伤的具体机制仍不清楚。光生物调节治疗运动性肌肉损伤只有在剂量和强度达到足够大情况下才有效,而且强度可能比剂量更重要,患部的有效照射剂量和强度受到皮肤厚度和光波波长的影响。由此推论,光生物调节疗法能有效地治疗运动性肌肉损伤,其疗效是剂量和强度依赖性的。  相似文献   
996.
It has been well documented that mutations in the same retinal disease gene can result in different clinical phenotypes due to difference in the mutant allele and/or genetic background. To evaluate this, a set of consanguineous patient families with Leber congenital amaurosis (LCA) that do not carry mutations in known LCA disease genes was characterized through homozygosity mapping followed by targeted exon/whole-exome sequencing to identify genetic variations. Among these families, a total of five putative disease-causing mutations, including four novel alleles, were found for six families. These five mutations are located in four genes, ALMS1, IQCB1, CNGA3, and MYO7A. Therefore, in our LCA collection from Saudi Arabia, three of the 37 unassigned families carry mutations in retinal disease genes ALMS1, CNGA3, and MYO7A, which have not been previously associated with LCA, and 3 of the 37 carry novel mutations in IQCB1, which has been recently associated with LCA. Together with other reports, our results emphasize that the molecular heterogeneity underlying LCA, and likely other retinal diseases, may be highly complex. Thus, to obtain accurate diagnosis and gain a complete picture of the disease, it is essential to sequence a larger set of retinal disease genes and combine the clinical phenotype with molecular diagnosis.  相似文献   
997.
Human cystic and alveolar echinococcoses are zoonotic diseases caused by the larval stages of Echinococcus granulosus and Echinococcus multilocularis, respectively. As the diseases are co-endemic in many areas of the world, a simple and rapid test for the differential diagnosis of cystic echinococcosis (CE) and alveolar echinocoocosis (AE) is needed. Here, we describe the development of an immunochromatographic test (ICT) using crude hydatid cyst fluid and a recombinant 18-kDa protein (rEm18) as antigens for the detection of E. granulosus and E. multilocularis antibodies in serum samples. The ICT was evaluated with serum samples from 195 echinococcosis patients from different endemic areas in northwestern China. These included 144 from CE patients, 51 from AE patients, 67 from patients with other parasitic diseases, 13 from patients with serous hepatic cysts, and 60 from healthy individuals. The sensitivity and specificity of the ICT for CE were 91.0 and 96.9 % and for AE were 98.0 and 99.3 % with diagnostic efficiencies of 94.1 and 99.1 %, respectively. No significant differences and high degrees of agreement were found between the ICT and an enzyme-linked immunosorbent assay for both CE and AE. Five serum samples from cysticercosis patients and one serum sample from a healthy control were found positive for CE with the ICT. These findings indicate that this test allows for discrimination between both forms of human echinococcosis. In conclusion, the ICT developed in this study is a promising tool for the simultaneous detection and discrimination of CE and AE. This test will be useful for serodiagnosis of CE and AE in clinical settings and screening programs.  相似文献   
998.

Background:

Interleukin-28B (IL28B) single nucleotide polymorphism (SNP) rs8099917 has been described to be associated with response to treatment with pegylated interferon and ribavirin (PEG-IFN/RBV) in patients with chronic hepatitis C from the North America, Europe, Asia countries like Japan and Taiwan. Whether this holds true for Chinese patients remains unknown.

Objectives:

We aimed to study the effects of IL28B rs8099917 on antiviral therapy responses in Chinese patients with hepatitis C.

Patients and Methods:

IL28B rs8099917 was genotyped in 263 patients with hepatitis C virus (HCV) infection and 244 healthy controls in Tianjin, China using TaqMan SNP genotyping method. The roles of rs8099917 and clinical characteristics in antiviral treatment were analyzed by logistic regression.

Results:

Among 263 patients with chronic HCV infection, 223 had a TT genotype (84.8%). Frequencies of TG/GG genotypes in patients with hepatitis C were significantly different from those of healthy controls (15.2% vs. 9.0%; P = 0.033). Patients with HCV infection had a higher G allele frequency than healthy controls (7.8% vs. 4.7%; P = 0.044). Univariate analysis revealed no significant association between rs8099917 and sustained virological response (SVR) (P = 0.612). However, it was found that HCV genotypes 2a/3a, age, prothrombin time (PT), albumin (ALB) and cholesterol (CHO) were associated with SVR. In multivariate analysis, only ALB was significantly an independent predictor of SVR (OR = 1.223; 95%CI: 1.046−1.430; P = 0.011).

Conclusions:

In contrast with T, rs8099917 G is a susceptible allele to HCV in China. ALB can independently predict SVR. Rs8099917 may play a quiet role to predict treatment response of patients with hepatitis C who received PEG−IFN/RBV therapy in China.  相似文献   
999.
美金刚在阿尔茨海默病患者中的疗效与耐受性多中心研究   总被引:1,自引:0,他引:1  
目的 评价美金刚对阿尔茨海默病(Alzheimer disease,AD)患者的疗效与安全性。方法多中心、随机、双盲、安慰剂对照研究。共纳入AD患者258例(MMSE检查5~18分),随机分入安慰剂组(PBO,n=130)或美金刚组(MEM,n=128),分别仅给予安慰剂或安慰剂及美金刚(10~20mg/d)治疗,共16周。主要疗效评估以坚持服用研究药物并在第16周接受严重障碍量表(SIB)评估的患者(完成16周研究集,CS16集)为对象,以SIB评分相对于基线的变化为指标;次要疗效评估分别以CS16集和全分析集(FAS)为对象,以MMSE、神经精神科问卷(NPI)和AD合作研究-日常生活能力量表(ADCS-ADL19)为指标。安全性评估包括体格检查、实验室检查、心电图和不良事件。结果 共236例患者(MEM 117例;PBO 119例)进入疗效分析,尽管两组的SIB评分均较基线时有所提高,两组的主要和次要疗效分析差异均无统计学意义(均P〉0.05)。Post—hoc数据评估发现有两个因素造成疗效分析结果的偏倚,舍弃受这些因素影响的患者数据后再次进行分析:美金刚组(n=94)的16周末SIB(MEM:PBO=2.2:0.3,P=0.04)、MMSE(MEM:PBO=1.0:0.1,P=0.03)和ADL评分变化(MEM:PBO=0.1:-1.6,P=0.02)与安慰剂组(n=95)差异均有统计学意义,提示美金刚的疗效优于安慰剂,显著改善AD患者的认知功能,并使日常生活能力维持稳定。美金刚的耐受性良好,其不良事件特征与安慰剂相似。结论 本研究为已有资料提供了更多支持,表明美金刚对中重度AD患者有效、安全且耐受性良好。  相似文献   
1000.
We synthesized an estrogen analog, ZYC-5, lacking activity at the classical estrogen receptor and examined its neuroprotective potential against necrosis induced by N-methyl-d-aspartate (NMDA) and apoptosis/necrosis induced by the NMDA receptor antagonist (+)-3-(2-carboxypiperazine-4-yl)-propyl-1-phosphonic acid (CPP). ZYC-5 protected cortical neurons in a dose-dependent manner, and the neuroprotection was more robust than with 17beta-estradiol. The effect of ZYC-5 was not mediated by the classical estrogen receptor, because it was unaffected by the antagonists 4-hydroxytamoxifen and ICI 182,780. The ZYC-5 protection against excitotoxicity was not directly mediated through the NMDA receptor, because there was no effect of ZYC-5 on NMDA current or the intracellular calcium increase induced by NMDA. Results obtained with the free-radical-sensitive dye, dihydroethidium, suggested that the neuroprotection of ZYC-5 was partly related to its radical scavenging properties. Although some of estrogen's neuroprotective effects may depend upon the estrogen receptor, our results suggest the possibility of neuroprotection without hormonal side effects.  相似文献   
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