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91.
A total of 72 HIV-1 infected Thai patients treated with didanosine (ddI) or stavudine (d4T) plus ddI at the time of interim analysis were analyzed. Sixty patients (83%) carried subtype E documented by HIV-1 V3 serotyping. HIV-1 RNA levels were measured using three commercial viral load assays. At baseline (n = 57), Quantiplex 2.0 and NucliSens 2.0 showed mean log10 HIV-1 RNA of 0.7 log10 or 5 fold lower than Amplicor 1.5 (mean 4.29 versus 5.0 log10, respectively, p < 0.001). At week 20 of treatment (n = 29), HIV-1 RNA levels were detected in 55.2%, 31%, and 33.5% of subjects tested by Amplicor 1.5, Quantiplex 2.0, and NucliSens 2.0, respectively. In conclusion: plasma HIV-1 RNA analyses showed comparable values with Quantiplex 2.0 and NucliSens 2.0 assays. In contrast, Amplicor 1.5 resulted in approximately 5 folds higher HIV-1 RNA levels and a 25% higher rate of detection of plasma HIV-1 RNA as compared to the other two assays. As the current goal of therapy is to suppress plasma viral load below the detection limit of the assays, the significant differences between the assays may influence antiretroviral efficacy evaluation and management.  相似文献   
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Determining the optimal conditions for learning anatomy will help medical students to do better in a gross anatomy course. We examined the two types of anatomy courses offered in our institution: slow-paced (SP) and fast-paced (FP) courses, in which the same content is taught in approximately the same number of hours (SP = 91 hr; FP = 90 hr), but the duration of each course differed (SP = 91 1-hr sessions lasting 20 weeks; FP = 45 2-hr sessions lasting 9 weeks). The objective of this study was to find out whether a relationship exists between anatomy course pace and achievement. Two groups of students were tested on their anatomy knowledge both before beginning and after completing either the SP or the FP course. The average difference in scores obtained on the pre- and postcourse tests for each group was obtained and a t-test was used (P < 0.05) to compare the mean score for each group. A significant difference was found between group SP and group FP, with the highest achievement obtained by group SP. The pace of the course is thus a factor that influences achievement.  相似文献   
95.
Lumpy skin disease virus (LSDV) is being developed as a vector for recombinant vaccines against diseases of veterinary importance. A strategy for generating viral thymidine kinase (TK) gene-disrupted recombinants which are stable and homogeneous using the South African Neethling vaccine strain of LSDV as vector has been developed. To assist with the selection process, the Escherichia coli beta-galactosidase (lacZ) visual marker gene was incorporated into the constructs. However, the use of lacZ has certain limitations. An improved strategy was then devised substituting lacZ with the enhanced green fluorescent protein (EGFP) under control of the vaccinia virus (VV) P11K late promoter. The EGFP marker was found to enhance the selection process, and with the inclusion of additional sonication and filtration steps the number of passages required to select recombinants to homogeneity has been reduced. In support of the improved method for generation and selection of recombinants described, three different LSDV recombinants expressing the glycoprotein genes of bovine ephemeral fever virus, Rift Valley fever virus and rabies virus were prepared and characterised.  相似文献   
96.
Lymphangioma is a disfiguring malformation of early childhood. A mouse lymphangioma model has been established by injecting Freund's incomplete adjuvant (FIA) intraperitoneally, but has not been compared with the human disease. We show that, in accordance with studies from the 1960s, the mouse model represents an oil-granuloma, made up of CD45-positive leukocytes and invaded by blood and lymph vessels. Several markers of lymphatic endothelial cells are expressed in both mouse and human, like CD31, Prox1, podoplanin, and Lyve-1. However, the human disease affects all parts of the lymphovascular tree. We observed convolutes of lymphatic capillaries, irregularly formed collectors with signs of disintegration, and large lymph cysts. We observed VEGFR-2 and -3 expression in both blood vessels and lymphatics of the patients, whereas in mouse VEGFR-2 was confined to activated blood vessels. The experimental mouse FIA model represents a vascularized oil-granuloma rather than a lymphangioma and reflects the complexity of human lymphangioma only partially.  相似文献   
97.
Intimacy and sexual expression are an integral part of being human and of healthy living. However, this important aspect of well-being is often overlooked or avoided when a person enters a care facility such as a nursing home, group home, or assisted living residence. This article summarizes the new Supporting Sexual Health and Intimacy in Care Facilities Guidelines, which suggest ways of supporting healthy intimacy and sexuality in care facilities.  相似文献   
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99.
Hemagglutinin esterases (HEs), closely related envelope glycoproteins in influenza C and corona- and toroviruses, mediate reversible attachment to O-acetylated sialic acids (Sias). They do so by acting both as lectins and as receptor-destroying enzymes, functions exerted by separate protein domains. HE divergence was accompanied by changes in quaternary structure and in receptor and substrate specificity. The selective forces underlying HE diversity and the molecular basis for Sia specificity are poorly understood. Here we present crystal structures of porcine and bovine torovirus HEs in complex with receptor analogs. Torovirus HEs form homodimers with sialate-O-acetylesterase domains almost identical to corresponding domains in orthomyxo- and coronavirus HEs, but with unique lectin sites. Structure-guided biochemical analysis of the esterase domains revealed that a functionally, but not structurally conserved arginine–Sia carboxylate interaction is critical for the binding and positioning of glycosidically bound Sias in the catalytic pocket. Although essential for efficient de-O-acetylation of Sias, this interaction is not required for catalysis nor does it affect substrate specificity. In fact, the distinct preference of the porcine torovirus enzyme for 9-mono- over 7,9-di-O-acetylated Sias can be explained from a single-residue difference with HEs of more promiscuous specificity. Apparently, esterase and lectin pockets coevolved; also the porcine torovirus HE receptor-binding site seems to have been designed to use 9-mono- and exclude di-O-acetylated Sias, possibly as an adaptation to replication in swine. Our findings shed light on HE evolution and provide fundamental insight into mechanisms of substrate binding, substrate recognition, and receptor selection in this important class of virion proteins.  相似文献   
100.
Title.  Music-assisted relaxation to improve sleep quality: meta-analysis.
Aim.  This paper is a report of a meta-analysis conducted to evaluate the efficacy of music-assisted relaxation for sleep quality in adults and elders with sleep complaints with or without a co-morbid medical condition.
Background.  Clinical studies have shown that music can influence treatment outcome in a positive and beneficial way. Music holds the promise of counteracting psychological presleep arousal and thus improving the preconditions for sleep.
Data sources.  We conducted a search in the Embase (1997 – July 2008), Medline (1950 – July 2008), Cochrane (2000 – July 2008), Psychinfo (1987 – July 2008) and Cinahl (1982 – July 2008) databases for randomized controlled trials reported in English, German, French and Dutch. The outcome measure of interest was sleep quality.
Methods.  Data were extracted from the included studies using predefined data fields. The researchers independently assessed the quality of the trials using the Delphi list. Only studies with a score of 5 points or higher were included. A pooled analysis was performed based on a fixed effect model.
Results.  Five randomized controlled trials with six treatment conditions and a total of 170 participants in intervention groups and 138 controls met our inclusion criteria. Music-assisted relaxation had a moderate effect on the sleep quality of patients with sleep complaints (standardized mean difference, −0·74; 95% CI: −0·96, −0·46). Subgroup analysis revealed no statistically significant contribution of accompanying measures.
Conclusion.  Music-assisted relaxation can be used without intensive investment in training and materials and is therefore cheap, easily available and can be used by nurses to promote music-assisted relaxation to improve sleep quality.  相似文献   
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