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81.
Thyrotropin-releasing hormone (TRH), 0.1 mg/kg, i.m., significantly counteracted pentobarbital narcosis in six monkeys, but melanocyte-stimulating-hormone-release-inhibiting factor (MIF), 0.1 mg/kg i.m., did not. Earlier dose-response studies in unanesthetized monkeys had shown that this dose of MIF stimulated motor activity; this dose of TRH had shown no stimulant effect, but a higher dose depressed activity. Thus, an MIF dose that stimulates unanesthetized monkeys does not reverse pentobarbital narcosis; a TRH dose that by itself is neither stimulant nor depressant does partially reverse pentobarbital narcosis.  相似文献   
82.
The authors investigated the influence of pregnancy and gender on the density of trigeminal and sympathetic perivascular nerves in posterior cerebral arteries (PCA) and the reactivity to norepinephrine and calcitonin gene-related peptide (CGRP). PCAs were isolated from nonpregnant, late-pregnant, postpartum, and male rats, mounted and pressurized on an arteriograph chamber to obtain concentration-response curves to norepinephrine and CGRP. Arteries were immunostained for CGRP-, tyrosine hydroxylase-, and protein gene product 9.5 (PGP 9.5)-containing perivascular nerves, and nerve density was determined morphologically. Pregnancy had a trophic effect on trigeminal perivascular innervation (P < .01 vs male); however, this was not accompanied by a change in reactivity to CGRP. Sympathetic and PGP 9.5 nerve densities were not altered by pregnancy or gender, and there were no differences in reactivity to norepinephrine. Together, these results suggest that the increase in trigeminal innervation during pregnancy is more related to nociception than in controlling resting cerebral blood flow.  相似文献   
83.
Viscosin (1), an effective surface-active cyclic lipopeptide, was efficiently recovered from Pseudomonas libanensis M9-3 with a simple purification protocol. A major pigment also obtained during this process was identified as phenazine-1-carboxylic acid. The critical micelle concentration (cmc) of viscosin was determined to be 54 mg L (-1), and the minimum surface tension between air and water at the cmc was 28 mN m (-1). Viscosin forms stable emulsions even at low concentrations (7.5 mg L (-1)), and the conditional stability constant for a cadmium-viscosin complex was determined to be 5.87. The physicochemical properties measured for viscosin are similar to other well-studied biosurfactants such as rhamnolipid and surfactin. Viscosin inhibited migration of the metastatic prostate cancer cell line, PC-3M, without visible toxicity. These properties suggest the potential of viscosin in environmental and biomedical applications.  相似文献   
84.
Physical injury that occurs as a result of intimate partner violence needs to be treated to relieve pain, promote healing, and prevent infection. Detection of physical injury is an important component of the forensic examination because of its role in criminal justice proceedings. Better detection and measurement techniques are needed to quantify physical injuries and advance the science. This article addresses current practices of injury identification, challenges in injury measurement, and future directions for research.  相似文献   
85.
This short survey of UK infertility counsellors was designed to determine whether the removal of donor anonymity resulted in noticeable changes in prospective parents' stated intentions regarding disclosure of their origins to any children conceived through donor conception. Members of the British Infertility Counselling Association working in Human Fertilisation and Embryology Authority (HFEA) -- licensed centres, before and after the legal changes, were sent a short questionnaire that included space for free comments (take-up: 62%). Three-quarters reported changes. Of these, two-thirds said prospective parents were more likely to say they would disclose, while less than a tenth said prospective parents were less likely do so. Where no changes were noted, this was primarily because the majority of prospective parents had stated their intention to be open even prior to the legal changes. Possible influences on intentions included: the culture within the centre, moves towards openness within the wider society, and parents' lack of confidence regarding how to go about disclosure. Follow-up studies are needed to improve understanding of whether influences on decision making carry through to patterns of actual disclosure; whether involvement in counselling affects outcomes; and whether access to professional assistance at the time of planned disclosure is helpful.  相似文献   
86.
New evidence has prompted changes in our national cardiopulmonary resuscitation guidelines for both neonates and adult patients. The purpose of this article is to provide an overview of the changes recommended by the American Heart Association, Academy of American Pediatrics, and the American College of Obstetrics and Gynecology. In addition, a strategy for implementing these guidelines into practice is suggested.  相似文献   
87.
BACKGROUND: For patients receiving home parenteral nutrition (HPN), catheter-related bloodstream infection (CRBSI) and reactive depression may significantly impact quality-of-life. This study evaluated the influence of patient affiliation with a national organization promoting HPN education and peer support on these outcome variables. METHODS: Using a case-control design, we compared 2 groups of affiliated patients with nonaffiliated controls, who were matched for diagnosis, HPN duration, sex, and age. Group 1 data were obtained from patients in large HPN medical practice programs. Group 2 data were obtained from patients in small medical practices with a small number of HPN patients. All participants were evaluated by structured interviews every 6 months over 18 months. RESULTS: In both data collection groups, affiliated patients (A) had significantly higher (mean +/- SD) quality-of-life scores compared with nonaffiliated patients (NA): (Gr 1: A, 19.8 +/- 4.7 versus NA, 17.6 +/- 5.6, p = .05; Gr 2: A, 20.4 +/- 5.2 versus NA, 17.3 +/- 4.8, p = .05). Affiliated patients also had lower depression scores (Gr 1: A, 10.9 +/- 10.4 versus NA, 20.4 +/- 13.6, p = .01; Gr 2: A, 12.5 +/- 9.6 versus NA, 18.5 +/- 10.8, p = .03) and a lower incidence of catheter-related infections (Gr 1: A, 0.10 +/- 0.3 versus NA, 0.60 +/- 0.55, p = .01; Gr 2: A, 0.27 +/- 0.55 versus NA, 0.71 +/- 0.64, p = .02) than nonaffiliated patients. CONCLUSIONS: Affiliation with an organization that provides ongoing HPN education and peer support was associated with significantly better HPN outcomes. Alternative explanations are discussed in relation to limitations of the case-control design.  相似文献   
88.
Norovirus is the leading cause of acute viral gastroenteritis. Both human and murine noroviruses attach to commensal bacteria belonging to the mammalian gut flora, and binding levels are influenced by nutrients present in bacterial media. However, it is not known which nutrients are responsible for altering viral binding or why binding is altered. Gene expression of commensal bacteria can be changed by the external environment as well as by interaction with pathogens. For example, growth phase and incubation conditions impact expression levels of specific bacterial genes in Escherichia coli. We have previously shown that binding by both human and murine noroviruses to the commensal bacterium Enterobacter cloacae induces genome-wide changes in gene expression with a large number of differentially expressed genes associated with the surface structure of the bacterial cell. The current study evaluated norovirus binding under nutrient-limited conditions and assessed the expression of a select panel of these genes that are significantly altered by norovirus binding under these conditions. The goal of this work was to determine how norovirus attachment to Enterobacter cloacae affected the expression of these genes under varying nutrient and growth phase conditions. We found that the presence of glucose in minimal media reduced murine norovirus binding to E. cloacae and viral binding in the presence of glucose reduced gene expression for surface structures previously associated with norovirus attachment. Changes in viral binding and gene expression occurred in a growth phase-dependent manner. Collectively, these data demonstrate that both the growth phase and nutrient availability alter viral interactions with commensal bacteria and the subsequent changes in gene expression. Ultimately, this work advances our understanding of norovirus-bacterium interactions and provides a foundation for elucidating the conditions and surface structures that regulate norovirus attachment to bacteria.  相似文献   
89.
90.
Objectives Progesterone has been shown to be neuroprotective in a number of preclinical central nervous system injury models including cerebral ischaemia. The aim of this study was to clarify differences in outcomes owing to different dosing regimens and the pharmacokinetic profile of progesterone, particularly in relation to brain levels. Methods Male C57 Bl/6 mice were injected intraperitoneally with progesterone (8 mg/kg in dimethylsulfoxide) or with a bolus injection followed by continuous subcutaneous infusion (1.0 µl/h of a 50 mg/ml progesterone solution) via implanted osmotic minipumps. Plasma and brain samples were collected over 24 h from bolus‐injected mice and 48 h from mice implanted with minipumps. Progesterone concentrations were measured by an enzyme‐linked immunoassay and pharmacokinetic profiles were constructed. Key findings Intraperitoneally injected progesterone had a short half‐life (fast component half‐life of 0.2 h) in both plasma and brain. Minipump delivery resulted in higher concentrations of progesterone in plasma and particularly in brain over a longer period. The volume of distribution with intraperitoneal injection was 172.78 versus 1641.84 ng/h per g via minipump in the first 24 h. Conclusions A bolus intraperitoneal loading dose of progesterone followed by continuous delivery via osmotic minipump is an effective way of delivering progesterone to the brain.  相似文献   
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