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991.
African American women have significantly higher mortality rates from heart disease and stroke than White women despite advances in treatment and the management of risk factors. Community health workers (CHWs) serve important roles in culturally relevant programs to prevent disease and promote health. This article describes the Pine Apple Heart and Stroke Project's activities to (1) revise the Women's Wellness Sourcebook Module III: Heart and Stroke to be consistent with national guidelines on heart disease and stroke and to meet the needs of African American women living in rural southern communities; (2) train CHWs using the revised curriculum; and (3) evaluate the training program. Revisions of the curriculum were based on recommendations by an expert advisory panel, the staff of a rural health clinic, and feedback from CHWs during training. Questionnaires after training revealed positive changes in CHWs' knowledge, attitudes, self-efficacy, and self-reported risk reduction behaviors related to heart disease, stroke, cancer, and patient-provider communication. This study provides a CHW training curriculum that may be useful to others in establishing heart disease and stroke programs in rural underserved communities.  相似文献   
992.
BACKGROUND: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and some related environmental contaminants are aryl hydrocarbon receptor (AhR) ligands that exert reproductive and developmental toxicity in laboratory animals. In humans, fertility-related effects are less documented. OBJECTIVE: The aim of this study was to investigate the relationship between dioxin-like biological activity in serum and parameters of reproductive status in men from the general population 5 months after a polychlorinated biphenyl and dioxin food-contamination episode in Belgium. DESIGN: In the framework of the cross-sectional Flemish Environment and Health Study (FLEHS), we recruited 101 men 20-40 years of age and evaluated sperm parameters, measured sex hormones, and gathered information on a number of lifestyle factors. In addition, we determined the AhR-mediated enzymatic response elicited by individual serum samples and expressed it as TCDD equivalent concentrations (CALUX-TEQs) using an established transactivation assay. RESULTS: Age (p = 0.04) and the frequency of fish (p = 0.02) and egg (p = 0.001) consumption were independent positive determinants of serum dioxin-like activity. After correcting for possible confounders, we found that a 2-fold increase in CALUX-TEQ > 16 pg/L was associated with a 7.1% and 6.8% (both p = 0.04) decrease in total and free testosterone, respectively. We also observed a more pronounced drop in semen volume of 16.0% (p = 0.03), whereas sperm concentration rose by 25.2% (p = 0.07). No relationship was found with total sperm count or sperm morphology. CONCLUSIONS: These data suggest an interaction of dioxin-like compounds with the secretory function of the seminal vesicles or prostate, possibly indirectly through an effect on testosterone secretion, at levels not affecting spermatogenesis as such.  相似文献   
993.
994.
A pooled analysis of second primary pancreatic cancer   总被引:1,自引:0,他引:1  
Studies of pancreatic cancer in the setting of second primary malignant neoplasms can provide etiologic clues. An international multicenter study was carried out using data from 13 cancer registries with a registration period up to year 2000. Cancer patients were followed up from the initial cancer diagnosis, and the occurrence of second primary malignant neoplasms was compared with expected values derived from local rates, adjusting for age, sex, and period of diagnosis. Results from individual registries were pooled by use of a fixed-effects model. People were at higher risk of developing pancreatic cancer within 10 years of a diagnosis of cancers of the pharynx, stomach, gallbladder, larynx, lung, cervix, corpus uteri, bladder, and eye and 10 years or later following a diagnosis of cancers of the stomach, colon, gallbladder, breast, cervix, placenta, corpus uteri, ovary, testis, bladder, kidney, and eye, as well as Hodgkin's and non-Hodgkin's lymphomas. Pancreatic cancer was connected with smoking-related cancers, confirming the etiologic role of tobacco. The associations with uterine and ovarian cancers suggest that reproductive factors might be implicated in pancreatic carcinogenesis. The elevated pancreatic cancer risk in young patients observed among several types of cancer implies a role of genetic factors. Radiotherapy is also suggested as a risk factor.  相似文献   
995.
The glomerular filtration barrier separates the blood from the urinary space and consists of two major cell types: podocytes and fenestrated endothelial cells. Mesangial cells sit between the capillary loops and provide structural support. Proliferation and loss of mesangial cells both are central findings in a number of renal diseases, including diabetic nephropathy and mesangiolysis, respectively. Using cell-specific gene targeting, it was shown previously that vascular endothelial growth factor A (VEGF-A) production by podocytes is required for glomerular endothelial cell migration, differentiation, and survival. For further investigation of the effect of gene dose and VEGF-A knockdown within the glomerulus, mice that carry one hypomorphic VEGF-A allele and one podocyte-specific null VEGF-A allele (VEGFhypo/loxP,Neph-Cre+/-) were generated; in these mice, the "allelic dose" of VEGF-A is intermediate between glomerular-specific heterozygous and null states. VEGFhypo/loxP,Neph-Cre+/- mice die at 3 wk of age from renal failure. Although endothelial cell defects are observed, striking loss of mesangial cells occurs postnatally. In addition, differentiated mesangial cells cannot be found in glomeruli of podocyte-specific null VEGF-A mice (VEGFloxP/loxP,Cre+/-). Together, these results demonstrate a key role for VEGF-A production in the podocyte for mesangial cell survival and differentiation.  相似文献   
996.
The cloning of the PKD1 and PKD2 genes has led to promising new insight into the mechanisms that are responsible for cyst development in patients with autosomal dominant polycystic kidney disease. Although the dominant pattern of inheritance would argue for haploinsufficiency, a gain of function, or a dominant negative mechanism, there is good evidence that autosomal dominant polycystic kidney disease behaves like a recessive disease on a cellular level (two-hit mechanism of cystogenesis). For testing of whether other pathomechanisms in addition to the two-hit hypothesis can explain cyst formation, two transgenic rat lines that contain a truncated human polycystin-2 cDNA were generated. The protein product lacks almost the entire COOH-terminus and mimics mutations that frequently are found in patients. The transgene-encoded mRNA could be detected in multiple tissues of both transgenic lines, with the highest expression in the kidney. Both lines present with renal cysts that originate predominantly from the proximal tubule; in the tubular epithelial cells, the epitope-tagged mutant protein was detected in the brush border and in primary cilia. Further evidence of the involvement of primary cilia stems from the finding of retinal degeneration in the transgenic rats and from the fact that stably transfected LLC-PK(1) cells that inducibly produced the truncated polycystin-2 protein elaborated shorter cilia. Other experimental approaches, such as a knock-in strategy, will be necessary to validate these results, but this is the first preliminary evidence that cyst formation is due not only to somatic mutations.  相似文献   
997.
CONTEXT: Approximately 20% of liver transplant recipients develop posttransplant diabetes mellitus. Hepatitis C, a leading indication for liver transplantation, has been identified as a risk factor for posttransplant diabetes mellitus and is an observation that is not well described. OBJECTIVE: To evaluate the incidence of posttransplant diabetes mellitus and risk factors associated with this condition. DESIGN: A retrospective chart review. SETTING: A large urban transplant center. PATIENTS: One hundred fifteen liver transplant recipients who received a transplant between January 1, 1998, and August 31, 2001. RESULTS: The rate of posttransplant diabetes mellitus, calculated at 3-month intervals in the first year after liver transplantation, ranged from 19.4% to 24.6%, which is similar to the averages reported in most published studies. The cumulative rate of posttransplant diabetes mellitus, which includes all patients who developed this condition during the time studied, was 31.3%. Clinical and demographic factors, including immunosuppression regimens, were similar between patients with and without posttransplant diabetes mellitus. Two risk factors for posttransplant diabetes mellitus were identified: hepatitis C, which was the leading indication for transplantation in this group (54.8%), and cytomegalovirus infection during the first year after transplantation. Other clinical and demographic variables, such as gender, age, ethnicity, rejection episodes, body mass index, and immunosuppression, were not identified as risk factors for posttransplant diabetes mellitus in liver transplant recipients.  相似文献   
998.
999.
CO2 laser skin resurfacing remains the gold standard for treatment of photoaged facial skin. It can be used onto the neck to further blend in the treated area with non-treated, adjacent photodamaged skin as well as improve the superficial textural quality of the neck skin. This article provides an overview of laser skin resurfacing of the neck, including pre-operative evaluation, patient education and selection, laser settings and technique used, post-operative care, and identification and treatment of possible complications.  相似文献   
1000.
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