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61.
62.

Background and purpose:

Lipid rafts and caveolae are membrane microdomains with important roles in cell survival signalling involving the Akt pathway. Cholesterol is important for the structure and function of these microdomains. The ginsenoside Rh2 exhibits anti-tumour activity. Because Rh2 is structurally similar to cholesterol, we investigated the possibility that Rh2 exerted its anti-tumour effect by modulating rafts and caveolae.

Experimental approach:

A431 cells (human epidermoid carcinoma cell line) were treated with Rh2 and the effects on cell apoptosis, raft localization and Akt activation measured. We also examined the effects of over-expression of Akt and active-Akt on Rh2-induced cell death.

Key results:

Rh2 induced apoptosis concentration- and time-dependently. Rh2 reduced the levels of rafts and caveolae in the plasma membrane and increased their internalization. Furthermore, Akt activity was decreased and consequently, Akt-dependent phosphorylation of Bad, a pro-survival protein, was decreased whereas the pro-apoptotic proteins, Bim and Bax, were increased upon Rh2 treatment. Unlike microdomain internalization induce by cholesterol depletion, Rh2-mediated internalization of rafts and caveolae was not reversed by cholesterol addition. Also, cholesterol addition did not restore Akt activation or rescue cells from Rh2-induced cell death. Rh2-induced cell death was attenuated in MDA-MB-231 cells over-expressing either wild-type or dominant-active Akt.

Conclusions and implications:

Rh2 induced internalization of rafts and caveolae, leading to Akt inactivation, and ultimately apoptosis. Because elevated levels of membrane rafts and caveolae, and Akt activation have been correlated with cancer development, internalization of these microdomains by Rh2 could potentially be used as an anti-cancer therapy.  相似文献   
63.

Background

New approaches to link health surveillance data with environmental and population exposure information are needed to examine the health benefits of risk management decisions.

Objective

We examined the feasibility of conducting a local assessment of the public health impacts of cumulative air pollution reduction activities from federal, state, local, and voluntary actions in the City of New Haven, Connecticut (USA).

Methods

Using a hybrid modeling approach that combines regional and local-scale air quality data, we estimated ambient concentrations for multiple air pollutants [e.g., PM2.5 (particulate matter ≤ 2.5 μm in aerodynamic diameter), NOx (nitrogen oxides)] for baseline year 2001 and projected emissions for 2010, 2020, and 2030. We assessed the feasibility of detecting health improvements in relation to reductions in air pollution for 26 different pollutant–health outcome linkages using both sample size and exploratory epidemiological simulations to further inform decision-making needs.

Results

Model projections suggested decreases (~ 10–60%) in pollutant concentrations, mainly attributable to decreases in pollutants from local sources between 2001 and 2010. Models indicated considerable spatial variability in the concentrations of most pollutants. Sample size analyses supported the feasibility of identifying linkages between reductions in NOx and improvements in all-cause mortality, prevalence of asthma in children and adults, and cardiovascular and respiratory hospitalizations.

Conclusion

Substantial reductions in air pollution (e.g., ~ 60% for NOx) are needed to detect health impacts of environmental actions using traditional epidemiological study designs in small communities like New Haven. In contrast, exploratory epidemiological simulations suggest that it may be possible to demonstrate the health impacts of PM reductions by predicting intraurban pollution gradients within New Haven using coupled models.  相似文献   
64.
Usual housing conditions lead to dominance hierarchy forming between male mice. The situation produces physiological and behavioural differences between dominants and subordinates. The goal of the present study was to assess stress responses, and possible changes in prepulse inhibition (PPI) of the startle reflex in dominant and subordinate male mice. Three weeks of daily social interactions led to stable aggressive dominance in 11 pairs of male NMRI mice. Stress levels were assessed by measuring faecal corticosterone metabolites (FCM), a non-invasive technique for monitoring hormonal changes in response to specific situations, with repeated sampling of each animal. The analysis of FCM levels showed greater stress in subordinate males at the beginning of the experiment, as the hierarchy was being established, but by the end of the experiment, FCM levels were reduced and similar in both dominants and subordinates. No significant differences were found in the startle response or PPI.  相似文献   
65.
Objectives:Congenital heart defects (CHD) are the most prevalent congenital anomalies. This study aims to examine the association between maternal occupational exposures to organic and mineral dust, solvents, pesticides, and metal dust and fumes and CHD in the offspring, assessing several subgroups of CHD.Methods:For this case–control study, we examined 1174 cases with CHD from EUROCAT Northern Netherlands and 5602 controls without congenital anomalies from the Lifelines cohort study. Information on maternal jobs held early in pregnancy was collected via self-administered questionnaires, and job titles were linked to occupational exposures using a job exposure matrix.Results:An association was found between organic dust exposure and coarctation of aorta [adjusted odds ratio (ORadj) 1.90, 95% confidence interval (CI) 1.01–3.59] and pulmonary (valve) stenosis in combination with ventricular septal defect (ORadj 2.68, 95% CI 1.07–6.73). Mineral dust exposure was associated with increased risk of coarctation of aorta (ORadj 2.94, 95% CI 1.21–7.13) and pulmonary valve stenosis (ORadj 1.99, 95% CI 1.10–3.62). Exposure to metal dust and fumes was infrequent but was associated with CHD in general (ORadj 2.40, 95% CI 1.09–5.30). Exposure to both mineral dust and metal dust and fumes was associated with septal defects (ORadj 3.23, 95% CI 1.14–9.11). Any maternal occupational exposure was associated with a lower risk of aortic stenosis (ORadj 0.32, 95% CI 0.11–0.94).Conclusions:Women should take preventive measures or avoid exposure to mineral and organic dust as well as metal dust and fumes early in pregnancy as this could possibly affect foetal heart development.  相似文献   
66.

Purpose

We have compared the mutational profiles of human breast cancer tumor samples belonging to all major subgroups with special emphasis on triple-negative breast cancer (TNBC). Our major goal was to identify specific mutations that could be potentially used for clinical decision making in TNBC patients.

Patients and methods

Primary tumor specimens from 149 Norwegian breast cancer patients were available. We analyzed the tissue samples for somatic mutations in 44 relevant breast cancer genes by targeted next-generation sequencing. As a second confirmatory technique, we performed pyrosequencing on selected samples.

Results

We observed a distinct subgroup of TNBC patients, characterized by an almost completely lack of pathogenic somatic mutations. A point mutation in the adenoviral E1A binding protein p300 (EP300-G211S) was significantly correlated to this TNBC subgroup. The EP300-G211S mutation was exclusively found in the TNBC patients and its presence reduced the chance for other pathological somatic mutations in typical breast cancer genes investigated in our gene panel by 94.9% (P?<?0.005). Interestingly, the EP300-G211S mutation also predicted a lower risk for relapses and decreased breast cancer-specific mortality during long-term follow-up of the patients.

Conclusion

Next-generation sequencing revealed specific mutations in EP300 to be associated with the mutational patterns in typical breast cancer genes and long-term outcome of triple-negative breast cancer patients.
  相似文献   
67.
We previously demonstrated that IL‐18 and CCL11 were highly expressed in an NFSA tumor cell line that showed limited angiogenesis and severe necrosis. However, IL‐18 was not responsible for the immune cell accumulation and necrosis. Here, we attempted to clarify the relevance of CCL11 in angiogenesis and tumor formation. We established CCL11‐overexpressing MS‐K cell clones (MS‐K‐CCL11) to assess the role of CCL11 in immune cell accumulation and angiogenesis. The MS‐K‐CCL11 cells did not form tumors in mice. MS‐K‐CCL11‐conditioned medium (CM) and recombinant CCL11 induced macrophage and eosinophil differentiation from bone marrow cells. The MS‐K‐CCL11‐CM effectively recruited the differentiated eosinophils. Furthermore, the eosinophils damaged the MS‐K, NFSA and endothelial cells in a dose‐dependent manner. Administration of an antagonist of CCR3, a CCL11 receptor, to NFSA tumor‐bearing mice restored the blood vessel formation and blocked the eosinophil infiltration into the NFSA tumors. Furthermore, other CCL11‐overexpressing LM8 clones were established, and their tumor formation ability was reduced compared to the parental LM8 cells, accompanied by increased eosinophil infiltration, blockade of angiogenesis and necrosis. These results indicate that CCL11 was responsible for the limited angiogenesis and necrosis by inducing and attracting eosinophils in the tumors.  相似文献   
68.
Background: Many studies that use food containing Panax genus plants (PGPs) have been conducted but most of them have not mentioned the effective compounds ginsenosides and their composition. Therefore, we conducted a systematic review and meta-analysis of time to exhaustion as an index of exercise endurance with ingestion of PGPs or ginsenosides to reveal their effects. Methods: We performed a systematic review with a comprehensive and structured literature search using seven literature databases, four clinical trial databases, and three general web search engines during 15–22 March 2021. A random-effects model was applied to calculate the standardized mean difference (SMD) and 95% confidence interval (CI) as the difference between the mean in the treatment and placebo groups. We evaluated the risk of bias of individual studies along with the risk of bias tool in the Cochrane handbook. This study was funded by Maruzen Pharmaceuticals Co., Ltd. (Hiroshima, Japan). The protocol for this study was registered with the UMIN-CTR (No. UMIN000043341). Results: Five studies met the inclusion criteria. The number of total participants was 90, with 59 in the ingestion-PGPs group and 64 in the control group, because three studies were crossover-design trials. We found that ingestion of PGPs or ginsenosides significantly improved exercise endurance (SMD [95% CI]: 0.58 [0.22–0.95], I2 = 0%). It was suggested that ginsenoside Rg1 (Rg1) and PGPs extract containing Rg1 were significantly effective in improving exercise endurance (SMD [95% CI]: 0.70 [0.14–1.27], I2 = 30%) by additional analysis. Conclusions: This systematic review suggests that the ingestion of PGPs or ginsenosides, especially Rg1, is effective in improving exercise endurance in healthy adults. However, further high-quality randomized controlled trials are required because imprecision and publication bias cannot be ignored in this systematic review.  相似文献   
69.
Murine MS‐K and NFSA cell lines formed tumor after inoculation into mouse and both cell lines expressed high level of vascular endothelial growth factor‐A (vegf‐A) and produced same level of VEGF‐A. However, poor blood vessel formation, and necrosis was significantly observed in NFSA‐tumor, contrary to well‐developed blood vessel formation in MS‐K tumor. The microarray analysis showed high expression of fibroblast growth factor‐10 (fgf‐10) in MS‐K than NFSA. In this report, the role of fgf‐10 on tumor growth was studied. MS‐K enhanced more proliferation of endothelial cells by direct co‐culture than NFSA, and rFGF10 supported the proliferation of HUVEC in combination with VEGF‐A. fgf‐10‐knocked down MS‐K, MS‐K (fgf‐10‐KD), proliferated slower in vitro and the tumorigenicity of them was also slower than control. The blood vessel formation in these MS‐K (fgf‐10‐KD) clones was reduced compared with the MS‐K (normal). qPCR analysis showed the suppression of vegf‐A, vegf‐C and fgfr‐1‐expression in the MS‐K (fgf‐10‐KD) clones. Taken together, these results indicated that FGF10, which was produced from tumor cells, was essential for the proliferation of tumor cell itself and also supports proliferation of endothelial cells. Thus, FGF10 plays an important role for tumor growth by both paracrine and autocrine manner.  相似文献   
70.
Objective. Vitamin D insufficiency appears to be a pandemic problem and is more common in inhabitants of high latitude compared to low latitude areas. We aimed to determine the prevalence of vitamin D deficiency/insufficiency in patients with psoriatic arthritis (PsA), its seasonal and geographic variation, and the possible association with demographics and disease activity.Methods. This study was conducted in a northern geographic area and in a subtropical region from March 2009 to August 2009. Most subjects were assessed in both winter and summer. Demographics, clinical data, skin photo type, and serum 25-hydroxyvitamin D (25[OH]D) levels were determined. Multivariate linear and logistic mixed models were used to assess the relationship with serum 25(OH)D levels.Results. In total, 302 PsA patients were enrolled. Two hundred fifty-eight patients were evaluated during the winter,while 214 patients were evaluated during the summer. 25(OH)D levels in winter and summer were adequate (north: 41.3%winter and 41.4% summer, south: 42.1% winter and 35.1% summer), insufficient (north: 55.7% winter and 58.6% summer,south: 50.9% winter and 62.2% summer), and deficient (north: 3% winter and 0% summer, south: 7% winter and 2.7%summer) among patients. There was no association between 25(OH)D levels, geographic and seasonal interaction, race,employment status, and skin photo type or disease activity in both seasons. No association between disease activity in summer and vitamin D levels in winter could be found.Conclusion. A high prevalence of vitamin D insufficiency among PsA patients was found. There was no seasonal variation in 25(OH)D levels among PsA patients in the southern and northern sites. No association could be established between disease activity and vitamin D level.  相似文献   
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