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Chondrocalcinosis, chronic pseudo-osteoarthritis arthropathy, and osteoporosis are classic osteoarticular complications of hemochromatosis (HC). Within HC, femoral head aseptic osteonecrosis (FHAO) is not notified in textbooks. We describe 3 cases of FHAO occurring in this setting in 3 patients homozygous for the C282Y mutation on HFE gene who had no other risk factors for FHAO. FHAO was diagnosed 9 years before (Case 1), concomitantly with (Case 3), or 9 years after HC (Case 2). In one case, FHAO occurred although phlebotomies were regularly carried out. There are scarce data available in the literature on HC and FHAO. Our observations suggest FHAO may be an indicator for HC, and iron balance should be determined before considering FHAO as idiopathic. Thus phlebotomy may not be protective against the occurrence of FHAO. Studies are needed to determine the prevalence of HC in consecutive patients with FHAO.  相似文献   
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MART-1(27-35)-peptide-pulsed immature dendritic cells (DCs) resulted in immunologic and clinical activity in a prior phase 1 trial. A phase 2 cohort expansion was initiated to further characterize the phenotype and cytokine milieu of the DC vaccines and their immunologic activity in vitro and to further examine a possible link between clinical activity and determinant spreading. In an open-label phase 2 trial, 10(7) autologous ex vivo generated DCs pulsed with the HLA-A*0201 immunodominant peptide MART-1(27-35) were administered to 10 subjects with stage II-IV melanoma. The experimental vaccines were administered intradermally in a biweekly schedule for a total of three injections, and blood for immunologic assays was obtained before each administration and at three time points after. DC vaccine preparations had wide intra- and interpatient variability in terms of cell surface markers and preferential cytokine milieu, but they did not correlate with the levels of antigen-specific T cells after vaccination. Of four patients with measurable disease, one had stable disease for 6 months and another has a continued complete response for over 2 years, which is confounded by receiving a closely sequenced CTLA4 blocking antibody. The DC vaccines induced determinant spreading in this subject, and CTLA4 blockade reactivated T cells with prior antigen exposure. The DC phenotype and cytokine profile do not correlate with the ability to induce antigen-specific T cells, while determinant spreading after DC immunization may be a marker of an efficient antitumor response. Sequential CTLA4 blockade may enhance the immune activity of DC-based immunotherapy.  相似文献   
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A commercially available repetitive-sequence-based PCR (rep-PCR) DNA fingerprinting assay adapted to an automated format, the DiversiLab system, enables rapid microbial identification and strain typing. We explored the performance of the DiversiLab system as a molecular typing tool for 69 Aspergillus isolates (38 A. fumigatus, 15 A. flavus, and 16 A. terreus isolates) had been previously characterized by morphological analysis. Initially, 27 Aspergillus isolates (10 A. fumigatus, 9 A. flavus, and 8 A. terreus isolates) were used as controls to create a rep-PCR-based DNA fingerprint library with the DiversiLab software. Then, 42 blinded Aspergillus isolates were typed using the system. The rep-PCR-based profile revealed 98% concordance with morphology-based identification. rep-PCR-based DNA fingerprints were reproducible and were consistent for DNA from both hyphae and conidia. DiversiLab dendrogram reports correctly identified all A. fumigatus (n = 28), A. terreus (n = 8), and A. flavus (n = 6) isolates in the 42 blinded Aspergillus isolates. rep-PCR-based identification of all isolates was 100% in agreement with the contiguous internal transcribed spacer (ITS) region (ITS1-5.8S-ITS2) sequence-based identification of the respective isolates. Additionally, the DiversiLab system could demonstrate strain-level differentiation of A. flavus and A. terreus. Automated rep-PCR may be a time-efficient, effective, easy-to-use, novel genotyping tool for identifying and determining the strain relatedness of fungi. This system may be useful for epidemiological studies, molecular typing, and surveillance of Aspergillus species.  相似文献   
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The objective of this study was to investigate the correlation between in vitro and in vivo liposome-complement interactions. Third component of the complement (C3) fragments associated with hydrogenated egg phosphatidylcholine (HEPC)-based liposomes in vivo and complement-dependent destabilization in vitro were determined as an indication of liposome-complement interaction in vivo and in vitro, respectively. C3 fragments on the liposomes were detected in both rats and guinea pigs. Pretreatment with K76COOH (K76), a complement inactivating agent, reduced the binding of C3 fragments. These findings indicated that the liposomes remarkably activated the complement system in both animals in vivo. Interestingly, significant complement-dependent liposome destabilization was observed in rat serum, but not in guinea pig serum, indicating that the liposomes activated the complement system in rats, but not in guinea pigs in vitro. Taken together, it is apparent that in vitro complement activation by the liposomes is not in agreement with in vivo complement activation in ginea pigs. This discrepancy in the liposome-complement interaction would suggest the need for further investigation to utilize the information obtained from the liposome-complement interaction to predict in vivo behavior of the liposomes.  相似文献   
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目的:在心肌缺血再灌注损伤中,炎症细胞因子参与其过程的多个环节。实验拟验证白细胞介素1、白细胞介素8因子在此过程中的动态变化,并分析其与药物干预的关系。方法:实验于2005-10/2006-11在新乡医学院形态学实验室完成。①实验分组:选择健康Wistar成年大鼠70只,按随机数字表法分为3组:对照组(n=10)、模型组(n=30)和药物组(n=30)。后两组又分为缺血0.5h,再灌注2,4,8,12,24h6个时相点,每个时相点5只。对照组只设12h一个时相点作为总体对照。②实验方法:大鼠麻醉后,药物组在右股静脉注入甲泼尼龙(30mg/kg),对照组及模型组注入生理盐水(0.75mg/kg)。采用夹闭左冠状动脉前降支建立大鼠心肌缺血再灌注损伤模型。对照组只开胸不夹闭。③实验评估:在各时相点观察各组大鼠缺血再灌注后的心肌细胞改变;血清学检测白细胞介素1、白细胞介素8因子的动态表达。结果:①模型组缺血再灌注12h炎细胞浸润最显著,药物组炎细胞呈散在浸润。②模型组和药物组白细胞介素1、白细胞介素8因子质量浓度明显高于对照组[缺血再灌注8h为例,白细胞介素1分别为(99.21±14.37),(85.77±11.31),(21.87±10.32)ng/L;白细胞介素8分别为(794.85±24.07),(536.95±19.72),(103.94±11.59)ng/L,P<0.05],峰值分别在缺血再灌注4,8h;同时相点药物组白细胞介素1、白细胞介素8因子质量浓度明显低于模型组(P<0.05)。结论:白细胞介素1和白细胞介素8因子在心肌缺血再灌注损伤的炎症反应中发挥着重要作用;甲泼尼龙对缺血再灌注损伤心肌有保护作用。  相似文献   
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In this paper, we address the issues of shortage and maldistribution of health personnel in southeast Asia in the context of the international trade in health services. Although there is no shortage of health workers in the region overall, when analysed separately, five low-income countries have some deficit. All countries in southeast Asia face problems of maldistribution of health workers, and rural areas are often understaffed. Despite a high capacity for medical and nursing training in both public and private facilities, there is weak coordination between production of health workers and capacity for employment. Regional experiences and policy responses to address these challenges can be used to inform future policy in the region and elsewhere. A distinctive feature of southeast Asia is its engagement in international trade in health services. Singapore and Malaysia import health workers to meet domestic demand and to provide services to international patients. Thailand attracts many foreign patients for health services. This situation has resulted in the so-called brain drain of highly specialised staff from public medical schools to the private hospitals. The Philippines and Indonesia are the main exporters of doctors and nurses in the region. Agreements about mutual recognition of professional qualifications for three groups of health workers under the Association of Southeast Asian Nations Framework Agreement on Services could result in increased movement within the region in the future. To ensure that vital human resources for health are available to meet the needs of the populations that they serve, migration management and retention strategies need to be integrated into ongoing efforts to strengthen health systems in southeast Asia. There is also a need for improved dialogue between the health and trade sectors on how to balance economic opportunities associated with trade in health services with domestic health needs and equity issues.  相似文献   
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