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91.
The tendency toward hypertension or higher blood pressure is more common in blacks than whites. The factors that account for these differences are attributed to both environmental and genetic factors. To clarify this issue, an anthropological study of black and nonblack populations in the lowland village of Chicaloma, northeastern Bolivia at a midaltitude of 1,800 m was conducted. The study included 159 subjects, of which 79 were black and 80 were nonblack, 17–78 years. The study suggests the following: (1) the socioeconomic status of blacks as measured by an ownership index is greater than that of nonblacks, (2) blacks had higher average systolic and diastolic blood pressures than nonblacks and showed an age-associated increase in blood pressures, (3) the prevalence of hypertension was higher for blacks (7–6%) than nonblacks (1.3%), but three times lower than among blacks in the United States, (4) skin reflectance is inversely related to blood pressures so that contrary to what has been suggested the darker the skin color, the higher the blood pressures even at comparable levels of affluence. These findings together suggest that genetic factors predispose black individuals to increased blood pressures, but the expression of clinical hypertension is influenced by adverse unaccounted environmental factors. Am. J. Hum. Biol. 11:489–498, 1999. © 1999 Wiley-Liss, Inc.  相似文献   
92.
Second cancer risk assessment for radiotherapy is controversial due to the large uncertainties of the dose-response relationship. This could be improved by a better assessment of the peripheral doses to healthy organs in future epidemiological studies. In this framework, we developed a simple Monte Carlo (MC) model of the Siemens Primus 6 MV linac for both open and wedged fields that we then validated with dose profiles measured in a water tank up to 30 cm from the central axis. The differences between the measured and calculated doses were comparable to other more complex MC models and never exceeded 50%. We then compared our simple MC model with the peripheral dose profiles of five different linacs with different collimation systems. We found that the peripheral dose between two linacs could differ up to a factor of 9 for small fields (5 × 5 cm2) and up to a factor of 10 for wedged fields. Considering that an uncertainty of 50% in dose estimation could be acceptable in the context of risk assessment, the MC model can be used as a generic model for large open fields (≥10 × 10 cm2) only. The uncertainties in peripheral doses should be considered in future epidemiological studies when designing the width of the dose bins to stratify the risk as a function of the dose.  相似文献   
93.
Inflammasome activation and IL-1β and IL-18 processing during infection   总被引:1,自引:0,他引:1  
Interleukin-1β (IL-1β) and IL-18 contribute to host defense against infection by augmenting antimicrobial properties of phagocytes and initiating Th1 and Th17 adaptive immune responses. Protein complexes called inflammasomes activate intracellular caspase-1 autocatalytically, which cleaves the inactive precursors of IL-1β and IL-18 into bioactive cytokines. In this review, we discuss the controversies regarding inflammasome activation and the role of the inflammasome during infection. We highlight alternative mechanisms for processing IL-1β and IL-18 during infection, which involve extracellular cleavage of the inactive cytokines by neutrophil-derived serine proteases or proteases released from cytotoxic T cells.  相似文献   
94.
Given the highly polymorphic nature of Human Leukocyte Antigen (HLA) molecules, it is not surprising that they function as key regulators of the host immune response to almost all invading pathogens, including SARS-CoV-2, the etiological agent responsible for the recent COVID-19 pandemic. Several correlations have already been established between the expression of a specific HLA allele/haplotype and susceptibility/progression of SARS-CoV-2 infection and new ones are continuously emerging. Protective and harmful HLA variants have been described in both mild and severe forms of the disease, but considering the huge amount of existing variants, the data gathered in such a brief span of time are to some extent confusing and contradictory. The aim of this mini-review is to provide a snap-shot of the main findings so far collected on the HLA-SARS-CoV-2 interaction, so as to partially untangle this intricate yarn. As key factors in the generation of antigenic peptides to be presented by HLA molecules, ERAP1 and ERAP2 role in SARS-CoV-2 infection will be revised as well.  相似文献   
95.
The IL-1 family member IL-38 (IL1F10) suppresses inflammatory and autoimmune conditions. Here, we report that plasma concentrations of IL-38 in 288 healthy Europeans correlate positively with circulating memory B cells and plasmablasts. IL-38 correlated negatively with age (p = 0.02) and was stable in 48 subjects for 1 year. In comparison with primary keratinocytes, IL1F10 expression in CD19+ B cells from PBMC was lower, whereas cell-associated IL-38 expression was comparable. In vitro, IL-38 is released from CD19+ B cells after stimulation with rituximab. Intravenous LPS in humans failed to induce circulating IL-38, compared to 100-fold induction of IL-6 and IL-1 receptor antagonist. In a cohort of 296 subjects with body mass index > 27 at high risk for cardiovascular disease, IL-38 plasma concentrations were significantly lower than in healthy subjects (p < 0.0001), and lowest in those with metabolic syndrome (p < 0.05). IL-38 also correlated inversely with high sensitivity C-reactive protein (p < 0.01), IL-6, IL-1Ra, and leptin (p < 0.05). We conclude that a relative deficiency of the B cell product IL-38 is associated with increased systemic inflammation in aging, cardiovascular and metabolic disease, and is consistent with IL-38 as an anti-inflammatory cytokine.  相似文献   
96.
We studied the effects of local IL-10 application, introduced by a recombinant human type 5 adenovirus vector, in the mouse knee joint during the early phase of CIA. One intra-articular injection with the IL-10-expressing virus (Ad5E1mIL-10) caused substantial over-expression of IL-10 in the mouse knee joint, using virus dosages which did not induce distracting inflammation. High expression of IL-10 was noted for a few days, being maximal at day 1. One intra-articular injection of Ad5E1mIL-10 in the knee joints of collagen type II (CII)-immunized mice, before onset of CIA was noted, reduced the incidence of collagen arthritis in that knee. Of high interest, the protective effect of local IL-10 expression by Ad5E1mIL-10 was not restricted to the knee joint alone. The arthritis incidence in the ipsilateral paw was highly suppressed. In contrast, local IL-10 over-expression was not effective when treatment was started after onset of CIA. Further analysis in the acute streptococcal cell wall-induced arthritis model revealed that local IL-10 over-expression markedly suppressed the production of tumour necrosis factor-alpha (TNF-alpha) and IL-1alpha, but had no significant effect on IL-1beta and IL-12 production in the inflamed synovium. These data indicate that local over-expression of IL-10 in the knee joint of mice regulates the expression of collagen arthritis, probably through down-regulation of TNF-alpha.  相似文献   
97.
Rodents subjected to chronic intermittent hypoxia (CIH) are used to investigate the mechanisms underlying the consequences of the obstructive sleep apnea (OSA) syndrome. Following CIH, rats have an increased density of noradrenergic terminals in the hypoglossal motor nucleus which innervates lingual muscles that protect the upper airway from collapse in OSA patients. Here, we investigated whether such an increase also occurs in other brainstem nuclei. Six pairs of male Sprague-Dawley rats were exposed to CIH or sham treatment for 10 h/day for 35 days, with O2 level oscillating between 24% and 7% every 3 min. Brainstem sections were immunohistochemically processed for dopamine-β-hydroxylase, a marker for norepinephrine. Noradrenergic terminal varicosities were counted in the center of the trigeminal motor nucleus (Mo5) and the interpolar part of the spinal trigeminal sensory nucleus (Sp5). In the Mo5, noradrenergic varicosities tended to be 9% more numerous in CIH- than sham-treated rats, and in the Sp5 they were 18% more numerous in CIH rats (184 ± 9 vs. 156 ± 8 per 100 × 100 μm counting box; p = 0.03, n = 18 section pairs).These data suggest that CIH elicits sprouting of noradrenergic terminals in multiple motor and sensory regions of the lower brainstem. This may alter motor and cardiorespiratory outputs and the transmission of cardiorespiratory and motor reflexes in CIH rats and, by implication, in OSA patients.  相似文献   
98.
BackgroundWestergren method, commonly used for erythrocyte sedimentation rate (ESR) determination, is simple and inexpensive. However, the 60 min required for the test are disadvantageous, especially for those departments/facilities where prompt evaluation is necessary. We investigated the possibility that earlier ESR recordings might correlate with standard 60-minute ESR and/or be predictive of the latter.MethodsDemographic and clinical data were collected from 220 randomly chosen adult patients hospitalised for various diseases in a medical department. ESR, determined by slightly modified Westergren method, was recorded at 15, 30 and 60 min. Correlation coefficients (r) between the standard and early ESR measurements were calculated for the entire group and for the separate subgroups divided according to patient age, sex and presence of anaemia or of inflammation.ResultsMean ± SD age of the patients was 61.3 ± 19.6, 55% were males; 45% had some inflammatory condition. Mean ± SD ESR values (mm) at 15, 30 and 60 min were 9.0 ± 12.1, 21.4 ± 21.8 and 35.9 ± 27.5, respectively. A statistically significant correlation was found between ESR measurements at 15 and 60 min (r = 0.833, p < 0.001). However, the strongest correlation was observed between 30 and 60 min measurements (r = 0.926, p < 0.001), irrespective of age, sex and presence of anaemia or of inflammation. Based on the ESR determination at 30 min (X), the predicted ESR value at 60 min (Y) could be calculated by a simple equation: Y = 10.7 + 1.2X.ConclusionSixty-minute ESR values can be predicted by the 30-minute estimation. Shortening the test by half an hour might bear practical importance.  相似文献   
99.

Background  

In a previous study we observed an increasing trend in candidemia in Finland in the 1990s. Our aim was now to investigate further population-based secular trends, as well as outcome, and evaluate the association of fluconazole consumption and prophylaxis policy with the observed findings.  相似文献   
100.
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