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101.
OBJECTIVE: To evaluate the association between high-risk human papillomavirus (HPV) DNA detection and histological diagnosis in women referred for atypical glandular cells (AGC) or adenocarcinoma in situ (AIS) at Pap smear. METHODS: In this cross-sectional study, 146 women referred for AGC (124), AGC with high-grade squamous intraepithelial lesion (HSIL) (15), or AIS (7) were tested for HPV DNA using Hybrid Capture II (HC II). All women underwent colposcopic examination, and cervical biopsy was performed for 95 patients. Fifty-one women referred due to AGC with normal colposcopy and normal second Pap smear were scheduled for control visits every 4 months. RESULTS: The overall prevalence of HPV DNA was 38%. HPV DNA was detected in 93% of the women with HSIL associated with AGC and in 71% of women with AIS Pap smear, being significantly higher when compared with the prevalence (29%) in women with AGC alone. Forty-five women (30.8%) had clinically significant histological lesions (CIN 2 or worse). High-risk HPV DNA was detected in only 16% of the women without significant abnormalities in biopsy, in contrast to 96% of those who had CIN 2 or CIN 3 and 75% of women with AIS. Eighty-five percent of women with invasive cervical carcinoma (squamous or adenocarcinoma) tested positive for HPV DNA. HPV DNA detection was significantly associated with histological diagnosis of CIN 2 or worse, with an odds ratio (OR) = 51.8 (95% CI 14.3-199.9). CONCLUSION: HPV DNA detection was strongly associated with the severity of cervical lesion (CIN 2 or worse) in women referred for AGC or AIS in their Pap smear. These data implicate the use of HPV testing in triage of women with AGC Pap smears.  相似文献   
102.
BACKGROUND: Monitoring of Epstein-Barr virus (EBV) reactivation after allogeneic hematopoietic stem-cell transplantation markedly improved with quantitative real-time polymerase chain reaction amplification of EBV DNA and visualization of EBV-specific CD8+ T cells with peptide-human leukocyte antigen (HLA) class I tetramers. We decided to combine these methods to evaluate posttransplant EBV reactivation and rituximab therapy. METHODS: We followed 56 patients treated with an HLA-genoidentical sibling (n=32), an HLA-matched unrelated donor (MUD, n=19), or an unrelated cord-blood transplant (n=5). EBV DNA was quantified in plasma and in peripheral blood mononuclear cells (PBMC). Patient CD8+ T cells were stained with a panel of eight tetramers. RESULTS: EBV DNA was detected in half of the patients, mainly in the MUD group (17/19). In 19 patients, viral DNA was detected only in the cellular compartment. All patients who controlled reactivation without rituximab and despite a viral load of greater than 500 genome equivalents (gEq)/150,000 PBMC mounted an EBV-specific CD8+ T-cell response in greater than 1.4% of CD3+CD8+ T cells. Plasmatic EBV genome was found in nine patients preceded by a high cellular viral load. Three of these patients controlled the reactivation before or without the introduction of rituximab, and they all developed a significant and increasing EBV-specific T-cell response. Patients with EBV-specific T cells at the onset of reactivation controlled viral reactivation without rituximab. CONCLUSION: This study emphasizes the benefit of an early and close monitoring of EBV reactivation and CD8+-specific immune responses to initiate rituximab only when necessary and before the immune response becomes overwhelmed by the viral burden.  相似文献   
103.
In this paper the association between smoking history, beverage consumption, diet and bladder cancer incidence is systematically reviewed. A rating system has been used to summarise the level of scientific evidence (i.e. convincing, probable, possible, and no evidence) and the level of association (i.e. substantially increased, (RR2.5), moderately increased (1.5RR<2.5), slightly increased (1.2RR<1.5), no association (0.8RR<1.2), slightly decreased (0.7RR<0.8), moderately decreased (0.4RR<0.7), and substantially decreased (RR<0.4)). There is convincing evidence that cigarette smoking status, frequency and duration substantially increase the risk of bladder cancer. However, the evidence is not clear for other forms of smoking. A small increased risk for cigar, pipe, and environmental smoking is only possible. There is possible evidence that total fluid intake is not associated with bladder cancer. Although there is convincing evidence for a positive association between alcohol consumption and bladder cancer risk in men, the risk is small and not clinically relevant. Coffee and tea consumption are probably not associated with bladder cancer. The authors conclude that total fruit consumption is probably associated with a small decrease in risk. There is probably no association between total vegetable intake, vitamin A intake, vitamin C intake and bladder cancer and a possibly moderate inverse association with vitamin E intake. Folate is possibly not associated with bladder cancer. There probably is a moderate inverse association between selenium intake and bladder cancer risk.  相似文献   
104.
Diarrhoeic stool samples from 334 0-5-year-old children were analysed with respect to the incidence of Bacteroides fragilis as well as other enteropathogens. B. fragilis was recovered in 9.3% (31/334) of the samples, and 79 strains were examined for the presence of the bft gene or the BfPAI flanking region using polymerase chain reaction assays. No enterotoxigenic B. fragilis strains were detected. In 29% (9/31) of the samples the coexistence of both II and III non-toxigenic B. fragilis (NTBF) patterns could be seen. In 51.6% (16/31) of the samples there existed a pattern II NTBF only, and in 19.4% (6/31) only pattern III could be detected. Strains from the same patient representing different patterns were submitted to pulsed-field gel electrophoresis assays. Fingerprints obtained by this technique showed that there was strong heterogeneity among strains from different individuals. However, different patterns from the same individual shared 100% similarity.  相似文献   
105.
Endogenous neuropeptide Y (NPY) levels increase during fasting and before dark onset in rats. The feeding that follows these states elicits the release of serotonin in the lateral hypothalamus (LH), as part of the physiological mechanisms controlling satiety. With the hypothesis that exogenous NPY-induced feeding should also stimulate serotonin, we measured its release in the LH of non-fasted rats, which received a single intracerebroventricular injection of either 1.0, 2.0, or 5.0 microg of NPY. After 1.0 microg, the cumulative 2-h intake was of 13 g and serotonin release significantly increased (54% peak). These feeding and serotonergic responses were highly similar to the ones we observed in a previous study, in which feeding followed an overnight fast. Thus, the 1.0 microg NPY dose stimulated intake while preserving the normal serotonergic activation. Contrarily, as the NPY dose was increased to either 2.0 or 5.0 microg, the cumulative 2-h intakes were of 18 g, but the serotonergic stimulation was absent. It is suggested that this dual NPY effect relies on a finely tuned control mechanism, reflecting the existence of a narrow range of NPY levels within which the serotonergic stimulation resembles those seen in physiological states.  相似文献   
106.
OBJECTIVE: Low visual acuity (VA) is an important public health problem due to its high prevalence and because it needs early diagnosis in order to prevent damage in childhood development and apprenticeship. To describe and analyze low visual acuity (VA) prevalence among school children. METHODS: Once performed the VA test to 1st and 4th grades primary school children data were analyzed by separating students according to sex, school grade, wearing of glasses, residence area and level of access to the supplementary medical assistance (SMA). RESULTS: The total of 9,640 students was evaluated during the year of 2000 and they presented a prevalence of low VA of 13.1% (CI 12.5-13.8%). There was a statistical significant lower prevalence in males (11.5%) compared to females (14.9%) - (PR=0.77). There was a statistical significant higher prevalence in 1st grade students (14.1%) compared to 4th grade (11.5%) - (PR=1.22). There was also a statistical significant lower prevalence for those who were not wearing glasses (12.1%) compared to those who were using glasses (42.0%) - (PR=0.29). Concerning to residence areas, Cajuru neighborhood had the lower prevalence of low VA (1.8%) and Vila Sabia neighborhood had the higher prevalence (32.4%), and a positive correlation, according to residence area, between the proportion of people with access to the Supplementary Medical Assistance and the proportion of children wearing glasses was found (r=0.64, p<0.001). CONCLUSIONS: The low VA high prevalence shows lack in early diagnosis and continuity of assistance pointing out to the urgent need of implementation in visual health public.  相似文献   
107.
Nowadays, nursing is sustained by different paradigms, among which we highlight those related to totality and simultaneity, since these embody the main conceptual models and specific theories for nursing practice. This study aims to provide elements that will lead to reflections about the possibility of founding health practices at ICUs on the Humanistic Theory of Paterson and Zderad, which is part of the simultaneity paradigm. This theory supports dialogue-based care, which is translated as the genuine encounter between and among caregivers, patients and their families. Thus, ICU care will go beyond the I-that relation, to achieve the I-you relation, that is, the subjectiveness of human beings.  相似文献   
108.
The authors studied the pharmacokinetics of sumatriptan nasal spray after a single dose in children migraineurs outside of migraine attack. Seventeen subjects (9 females) ages 6 to 11 years were given one dose of sumatriptan nasal spray based on age and weight; children 6 to 8 years of age weighing 25 kg and children ages 9 to 11 years of age weighing 40 kg received 20 mg (n = 4). Plasma sumatriptan concentrations were determined in serial blood samples obtained over 8 hours. Pharmacokinetic analysis included both noncompartmental and population modeling methods. The pharmacokinetic parameter estimates (geometric mean [95% confidence interval]) following 5, 10, and 20 mg sumatriptan were, respectively, as follows: maximum concentration = 8.1 ng/mL (3.6-18.4), 10.8 ng/mL (7.7-15.4), and 12.3 ng/mL (7.6-19.9); half-life = 1.4 hours (1.2-1.8), 1.7 hours (1.4-2.0), and 1.7 hours (1.3-2.3); and AUC = 27.8 ng*h/mL (9.7-79.8), 42.4 ng*h/mL (30.6-58.8), and 49.2 ng*h/mL (32.9-73.7). The median time to maximum concentration for all groups was 2 hours. Population pharmacokinetic modeling included pooled data from this study and from an adolescent study (n = 16). Clearance (CL/F) was 197 L/h for a 30-kg child with between-subject variability of 28%, and the volume of distribution was 751 L, normalized for an 11-year-old child with variability of 43%. The covariate analysis showed that volume increases with age and clearance increases with body size. The absorption was complex, often displaying double-peak plasma concentrations, with a rapid absorption phase and a delayed and rate-limited absorption phase. The dosing scheme based on age and weight resulted in maximal concentrations (C(max)) and systemic exposure (AUC) that were comparable to those observed in adolescents and adults treated with 20 mg. The age- and weight-adjusted dosing scheme appears to an appropriate initial dosing regimen for children with migraine headache. Appropriate safety and efficacy trials will need to be completed in children prior to recommending its use in children.  相似文献   
109.
We used a short‐term bioassay—the Tradescantia stamen‐hair assay (TSH)—to evaluate the toxicity of ambient particles with an aerodynamic diameter less than 10 μm sampled in the metropolitan region of São Paulo, Brazil. Two exposure locations were selected: downtown São Paulo and Caucaia do Alto (mean PM10 levels of 64 and 14 μg/m3, respectively). The experiment was conducted July 11–August 15, 2002, and toxicity was assessed with the Tradescantia stamen‐hair assay (TSH) employing clone KU‐20 of Tradescantia. Four experimental groups were defined: inflorescences collected from plants cultivated in Caucaia, inflorescences collected from plants cultivated in São Paulo (to establish the baseline level of mutations in stamen hairs at both sites), inflorescences collected from plants cultivated in Caucaia and brought to São Paulo and maintained in chambers that received ambient air, and inflorescences collected from plants cultivated in Caucaia and brought to São Paulo and maintained in chambers that received air passed through a particle filter. The frequency of mutations observed in Caucaia was significantly lower than that in the remaining groups. Flower cuttings brought from Caucaia and receiving ambient air of São Paulo showed a rate of mutations similar to that of plants cultivated in São Paulo. Filtering particles from the air reduced the rate of mutation but not sufficiently to reach the level of that in Caucaia. The frequency of mutations observed in São Paulo was significantly associated with PM10 levels on the fifth day before the opening of the flowers (r = 0.47, p = 0.025). Our results indicate that urban particles play a significant role in the development of pollution‐dependent mutations. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 578–584, 2004.  相似文献   
110.
Deltamethrin (DTM) is a synthetic pyrethroid insecticide used wideworld in agriculture, home pest control, protection of foodstuff, and disease vector control. It has widespread applications in Brazilian agriculture. The effects of DTM on mitochondrial respiratory parameters and on the organization of artificial and native membranes are described. DTM (200 nmol mg(-1) protein) on isolated liver mitochondria decreased oxygen consumption of both, state III and state IV, as well as the inner mitochondrial membrane potential (Deltapsi). Analysis of segments of the respiratory chain suggested that the DTM inhibition site is located between complex II and complex III. Mitochondrial swelling, energized or driven by the K+ diffusion potential using valinomycin, were partially inhibited by DTM (200 nmol mg(-1) protein). Fluorescence polarization of DPH and DPH-PA, probing the core and outer regions, respectively, of dimyristoylphosphatidylcholine (DMPC) and native mitochondrial membranes, indicated that DTM shifts the midpoint phase transition to lower values, besides broadening the phase transition. DTM decreased the lipid order of DMPC bilayers, at temperatures lower than the transition temperature and also caused a disordering effect on native membranes. However at temperatures above the transition temperature, the pesticide increased the rigidity of the membrane. These results suggest that DTM causes perturbations in lipid-lipid and lipid-protein interactions, interferes in transport mechanisms operating at the membrane level, and causes alterations of membrane permeability and mitochondrial enzyme activities. These effects could be associated with the toxicity of deltamethrin.  相似文献   
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