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991.
BACKGROUND: Interleukin (IL)-12 is a cytokine with protean effects against bacterial and intracellular pathogens. Induction of IL-12 at the time of infection has salient effects on elimination of various microbes. This work describes the effect of exposure to ethanol on lipopolysaccharide (LPS)-induced production of IL-12 in mice and whether ethanol-induced increases in IL-10 mediates these changes in IL-12 production. METHODS: BALB/c mice were pretreated with ethanol and then challenged with LPS either intravenously (iv) or intratracheally (it), and blood and lung production of IL-12 (p70 and p40 components) and serum IL-10 were assayed. Splenic and lung mRNA for IL-12 p35 and p40 components was determined. RESULTS: Ethanol pretreatment suppressed LPS-induced IL-12 p70 and p40 protein production in blood and lung. In spleen and lung, p40 mRNA was induced to a greater extent than p35 mRNA, and there was greater suppression of p40 mRNA compared with p35 mRNA in ethanol-treated animals. Ethanol up-regulated the production of IL-10, and pretreatment of these animals with a polyclonal anti-IL-10 antibody resulted in significant increases in IL-12 p70 and p40 levels, but not completely to those of control animals. CONCLUSIONS: Ethanol suppresses the production of murine IL-12 in response to LPS in blood and lung, with both the p70 and the p40 components affected. This suppression is accompanied by reductions of p40 mRNA in both spleen and lung. IL-10 may play a role in ethanol-induced suppression of IL-12, as neutralization of IL-10 partially attenuated the suppression of IL-12.  相似文献   
992.

Background  

Neoplastic cells increase glycolysis in order to produce anabolic precursors and energy within the hypoxic environment of a tumor. Ras signaling is activated in several cancers and has been found to regulate metabolism by enhancing glycolytic flux to lactate. We examined the effects of sequential immortalization and H-RasV12-transformation of human bronchial epithelial cells on the anabolic fate of fully-labeled 13C-glucose-derived carbons using two-dimensional total correlated spectroscopic analysis-nuclear magnetic resonance spectroscopy (2D TOCSY-NMR).  相似文献   
993.
994.
PURPOSE: To determine the effect of inhibition of insulin-like growth factor-IR (IGF-IR) signaling with an antibody to the IGF-IR, A12, in conjunction with androgen withdrawal on prostate cancer progression in a human prostate xenograft model, LuCaP 35. EXPERIMENTAL DESIGN: LuCaP 35 was implanted s.c. in severe combined immunodeficient mice. At the time of castration, mice were randomized to one of three groups. Group 1 was castrate only; group 2 received A12 40 mg/kg i.p. for 2 weeks beginning 1 week after castration; and group 3 received A12 40 mg/kg i.p. for 2 weeks beginning 2 weeks after castration. RESULTS: In group 1, tumor volume decreased to 60% of the starting volume 4 weeks post-castration. In groups 2 and 3, tumor volumes nadired 6 weeks after castration at <10% of the volume at time of castration (P < 0.01). Tumor regrowth was not seen in groups 2 or 3 until 15 weeks after castration. Androgen receptor (AR) localization in tumors showed a decrease in nuclear staining in groups 2 and 3 compared with group 1 (P < 0.001). Tumor volume correlated with nuclear AR intensity. AR-regulated genes increased early in group 1, but did not increase in groups 2 and 3. Thus, tumor-specific survival was prolonged by the addition of A12 to castration. Conclusions: This study shows that the inhibition of IGF-IR enhances the effects of castration in prostate cancer. These effects are associated with a decrease in AR signaling and nuclear AR localization, and recurrence is associated with an increase in AR-regulated gene expression.  相似文献   
995.
目的:应用组织多普勒显像(TDI)技术评价卡维地洛对高血压患者左室舒张功能的影响.方法:对30例高血压给予卡维地洛治疗24周.治疗前、治疗后12周、24周用TDI技术测量左室收缩期二尖瓣环平均舒张早期运动速度(Ea)、舒张晚期运动速度(Aa)及Ea/Aa,并与血流多普勒指标E波速度(E)、A波速度(A)、E/A进行比较,观察降压效果及对左室舒张功能的影响.结果:卡维地洛治疗12周后收缩压(SBP)、舒张压(DBP)、心率(HR)均较治疗前下降(P<0.05),Ea、Ea/Aa均较治疗前升高(P<0.05),治疗24周后E、E/A较治疗前升高(P<0.05),Aa较治疗前降低(P<0.05),Ea、Ea/Aa有进一步改善的趋势(P<0.05).结论:TDI技术在评价左室舒张功能方面较二尖瓣血流频谱更敏感;卡维地洛对轻、中度高血压具有良好的降压作用,且能改善患者左室舒张功能.  相似文献   
996.
997.
The occurrence of azaspiracid (AZA) toxins in contaminated shellfish has been the focus of much research. The present study investigated the binding properties of these toxins in mussels of the species Mytilus edulis. The work involved extraction of proteins and AZAs from contaminated mussel hepatopancreas and examination of the extracts by isoelectric focusing (IEF), size exclusion chromatography (SEC) and sodium docecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Liquid chromatography coupled with tandem mass spectrometry analysis (LC-MS/MS) was also performed in this study to identify AZAs. Blank mussels were subjected to the same purification and analytical procedures. AZAs were found to be weakly bound to a protein with a molecular weight of 45 kDa, in samples of contaminated mussels. This protein, which was abundant in contaminated mussels, was also present in blank mussels, albeit at much lower concentrations. It was further noted that a 22 kDa protein was also present only in contaminated mussel samples.  相似文献   
998.
Background:  This article outlines issues of service provision for Indigenous families in Brisbane, Australia. It presents guidelines for the development of a socially and culturally appropriate occupational therapy service for urban Indigenous children.
Methods:  A mixed methodology was used in two independent components of the research. Part 1 comprised a survey of paediatric occupational therapists in Brisbane. Part 2 consisted of focus groups and interviews with recipients of a newly established occupational therapy service for Indigenous children.
Results:  Survey findings indicated that very few Indigenous families access mainstream occupational therapy services. Issues and strategies for developing culturally appropriate practice emerged around five main themes. These were the need to develop effective relationships, develop particular personal qualities, understand the background of both the client and the therapist, both gain and give knowledge, and address logistical issues of service delivery.
Conclusions:  Service providers need to understand the social and cultural context of both their Indigenous clients and themselves. Recommendations for future education and practice are provided.  相似文献   
999.

Background  

Smear-negative pulmonary tuberculosis (SNPTB) accounts for 30% of Pulmonary Tuberculosis (PTB) cases reported annually in developing nations. Polymerase chain reaction (PCR) may provide an alternative for the rapid detection of Mycobacterium tuberculosis (MTB); however little data are available regarding the clinical utility of PCR in SNPTB, in a setting with a high burden of TB/HIV co-infection.  相似文献   
1000.
Nelson CR  Knapp DA 《Hypertension》2000,36(4):600-603
This study assessed trends from 1980 to 1995 in ambulatory patients' antihypertensive drug therapy by US office-based physicians for visits in which hypertension was the principal diagnosis and compared these trends with the respective guidelines given in 5 Joint National Committee (JNC) Reports on Detection, Evaluation, and Treatment of High Blood Pressure published around the same time period. Data from the National Center for Health Statistics' National Ambulatory Medical Care Surveys for 1980, 1985, 1990, and 1995 were used. From 1980 to 1995, there was no significant trend in the percentage of hypertension visits that did not mention any antihypertensive drug (20% to 27%). Further analyses focused on those hypertension visits in which at least 1 antihypertensive drug was used. Across the years, antihypertensive drug visits mentioning calcium channel blockers or ACE inhibitors significantly increased; those noting diuretics significantly decreased. However, in 1995, antihypertensive drug visits that included a diuretic and/or a beta-adrenergic blocker equalled 53%; these are the antihypertensive drug classes preferred by the JNC V. Physician antihypertensive drug prescribing was generally consistent with the basic antihypertensive drug guidelines of the JNC reports.  相似文献   
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