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1.
We examined seven 1-d diet records kept during 1 y by 272 men and women instructed to follow a lipid-lowering diet while participating in a clinical trial of pravastatin, a new 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor. The mean percentage of calories from total fat and saturated, unsaturated, and monounsaturated fatty acids was similar throughout the year even though the patients knew they were taking an effective lipid-lowering agent. However, the diets of greater than 40% of women included less than two-thirds of the recommended dietary allowance (RDA) of folic acid, vitamins B-6 and D, and calcium and zinc; in men, folic acid and zinc intakes were low. We conclude that patients comply with lipid-lowering diets even when they know that they are receiving an effective serum lipid-lowering agent. However, for both men and women special attention should be given to the intake of several nutrients.  相似文献   
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This work is a review of the mechanical factors related to low back pain production in a vibration environment. The sitting posture is an extreme orientation for the lumbar intervertebral disc that 1) increases its internal pressure, 2) increases its anteroposterior shear flexibility, while: 3) decreasing its resistance to buckling instability and 4) stressing the posterior region of the disc. Vibration is an additional mechanical stressor. Several studies suggest that the following preventive measures be taken to reduce the risk of low back pain due to driving: 1) minimize the vibration reaching the driver, 2) avoid lifting or bending immediately following driving, and 3) walk around for a few minutes following driving. © 1993 Wiley-Liss, Inc.  相似文献   
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Experiments were performed to examine the interaction of tuberculin with platelets and complement. Hemolytic complement titrations show that tuberculin consumes complement in human, rabbit, and guinea pig serum. Evidence in support of classical pathway activation was provided by observation of C1 consumption and failure to detect significant conversion of alternative pathway factor B to B by immunoelectrophoresis. Platelets in plasma from guinea pigs deficient in the fourth component of complement were not affected by tuberculin. However, studies on platelet aggregation in plasma chelated with ethyleneglycolbis(beta-aminoethyl ether)-N,N-tetraacetic acid indicated that tuberculin may initiate sluggish activation of the alternative pathway. That the reaction between tuberculin and platelets is a lytic one was evidenced by observing the release of the cytoplasmic enzyme lactic dehydrogenase and efflux of rubidium-86. Studies with C6-deficient rabbits indicated that platelet release of exogenously supplied tritiated serotonin is caused by platelet lysis.  相似文献   
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Zusammenfassung Beschrieben wird ein Fall von in vivo diagnostiziertem Hydrops des Cavum septi pellucidi mit schizophrener Psychose, welche nach zweimaliger Encephalographie zur Rückbildung kam. Das klinisch-röntgenologische Pellucidum-Syndrom wird erörtert.  相似文献   
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Rheumatoid arthritis (RA) is a common, chronic, autoimmune, inflammatory disease that is influenced by genetic factors including gender. Many studies suggest that the genetic risk for RA is determined by the MHC, in particular class II alleles with a 'shared epitope' (SE), and multiple non-MHC loci. Other studies indicate that RA and other autoimmune diseases, in particular insulin-dependent diabetes mellitus (IDDM) and autoimmune thyroid disease (ATD), share genetic risk factors. Rat collagen-induced arthritis (CIA) is an experimental model with many features that resemble RA. The spontaneous diabetes-resistant bio-breeding rat, BB(DR), is of interest because it is susceptible to experimentally induced CIA, IDDM and ATD, and it has an SE in its MHC class II allele. To explore the genetics of CIA, including potential gender influences and the genetic relationships between CIA and other autoimmune diseases, we conducted a genome-wide scan for CIA regulatory loci in the F(2) progeny of BB(DR) and CIA-resistant BN rats. We identified 10 quantitative trait loci (QTLs), including 5 new ones (Cia15, Cia16*, Cia17, Cia18* and Cia19 on chromosomes 9, 10, 18 and two on the X chromosome, respectively), that regulated CIA severity. We also identified four QTLs, including two new ones (Ciaa4* and Ciaa5* on chromosomes 4 and 5, respectively), that regulated autoantibody titer to rat type II collagen. Many of these loci appeared to be gender influenced, and most co-localized with several other autoimmune trait loci. Our data support the view that multiple autoimmune diseases may share genetic risk factors, and suggest that many of these loci are gender influenced.  相似文献   
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It has been suggested that streptococcal cell wall-induced arthritis in LEW/N rats resembles a localized neoplasm consisting of, in part, a proliferative and invasive population of fibroblast-like synoviocytes. To further pursue this concept, the synoviocytes from diseased rats were characterized in situ and in vitro for various parameters of "transformation." The spindle-shaped synoviocytes were found throughout the synovium and were the predominant cell type at sites of invasion of bone and cartilage by synovium. They stained intensely for vimentin, a microfilament prominently expressed in immature and transformed mesenchymal cells. They stained variably for Ia antigens and did not exhibit T cell surface antigens nor did they stain with histochemical stains characteristic of monocytes or granulocytes. Electron microscopy confirmed their fibroblastlike morphology and suggested high grade metabolic activity. In primary culture, the abnormal synoviocytes were adherent, grew rapidly and did not contact inhibit. Moreover, they grew under anchorage-independent conditions. These abnormal growth characteristics were inhibited by all-trans retinoic acid. Finally, explants of the arthritic synovium formed short-lived tumorlike nodules in athymic nude mice. These observations, considered in the context of other data, support the concept that the pathologic process represents a thymic-dependent, nonmalignant, locally invasive inflammatory neoplasm.  相似文献   
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BACKGROUND: Kaposi's sarcoma (KS) is caused by Kaposi's sarcoma associated herpesvirus (KSHV/HHV-8), the eighth Herpesvirus found to infect humans. The molecular epidemiology of KSHV is related closely to ethnicity and geographical location of studied populations. There is little epidemiological and molecular information about KSHV strains circulating in Brazil. OBJECTIVES: To characterize KSHV strains isolated from AIDS patients with Kaposi's sarcoma (AIDS-KS) in Sao Paulo, Brazil, and to examine associations between KSHV subtypes, ethnicity and HIV risk categories. METHODS: AIDS-KS patients were recruited consecutively at the largest AIDS reference hospital in Sao Paulo. Fragments (420 bp) of the VR1 and VR2 regions of KSHV open reading frame (ORF) K1 were amplified by nested PCR and sequenced directly. RESULTS: We analysed 37 samples from 33 patients, and found subtypes A-C in 48%, 21% and 30% of patients respectively, including two patients infected with subtype A5, a first report from Brazil. Sexual orientation was associated with subtype: 12/14 (86%) patients with subtype A were male homo/bisexual, compared with 3/8 (38%) among patients infected with subtype C (P = 0.05). A higher proportion of male patients with subtype C were of Caucasian origin (7/8 (87%)), compared with 7/16 (44%) among male patients with subtype A (P = 0.08). CONCLUSIONS: This first detailed report of KSHV subtypes among AIDS-KS patients in Brazil reports the first isolation of KSHV subtype A5 in this country, and suggests KSHV strain transmission between different ethnic groups, and association of specific strains with sexual orientation.  相似文献   
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