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111.
Teams in seven developing countries have adopted a common research design to evaluate new community mental health care services. The nature of the intervention programs varied considerably according to the characteristics of each area. Observations made before the intervention and 18 to 24 months after showed significant changes in the attitudes, knowledge, and diagnostic accuracy of health staff and in community attitudes and reactions. A considerable number of individuals with serious mental disorders received effective care for the first time.  相似文献   
112.
1 Urocortin is a vasodilator peptide related to corticotrophin-releasing factor, which may protect endothelial function during coronary ischemia-reperfusion (I-R). The aim of this study was to study the mechanisms of this protective effect. 2 Hearts from Sprague-Dawley rats were isolated and perfused at constant flow and then exposed to 15 min global zero-flow ischemia, followed by 15 min reperfusion. The relaxation to acetylcholine (10 nM-10 microM) was recorded after pre-constriction of the coronary vasculature with U46619 (100-300 nM) in ischemic-reperfused or time-control hearts. 3 After I-R, the coronary relaxation to acetylcholine was reduced and this reduction was attenuated by treatment with urocortin (10 pM), administered before ischemia and during reperfusion. 4 This urocortin-induced improvement of the relaxation to acetylcholine was not modified by tetraethylammonium (10 mM), blocker of Ca2+ dependent-potassium channels; glibenclamide (10 microM), blocker of K(ATP) channels; N(w)-nitro-L-arginine methyl ester (L-NAME, 100 microM), blocker of nitric oxide synthesis; or meclofenamate (10 microM), blocker of cyclooxygenase, but it was abolished by chelerythrine (3 microM), blocker of protein kinase C (PKC). 5 These results suggest that urocortin may protect coronary endothelial function during I-R by activation of PKC.  相似文献   
113.
It is well known that exposure to extreme environments, such as in high-mountain expeditions, is associated with increased production of reactive oxygen species and related oxidative damage. However, there is little information concerning antioxidant recovery after this type of expedition. Thus, the aim of this study is to analyze the antioxidant recovery status at sea level of five expert alpinists 4?weeks after climbing Cho-Oyu (8,201?m). Body composition, cardiorespiratory capacity, and circulating parameters were almost similar to the values obtained at the beginning of the study. However, the alpinists presented high erythrocyte number, related hemogram values, and ferritin. Sodium, alkaline phosphatase, and γ-glutamyltransferase plasma levels were lower. Concerning oxidative stress, plasma uric acid levels were significantly increased, as well as malondialdehyde and protein carbonyls. Neutrophils displayed significantly higher levels of malondialdehyde and lower catalase activity. Therefore, these data indicate that the oxidative stress during a high mountain expedition is the most probable cause to explain an incomplete recovery in plasma and neutrophil antioxidant status.  相似文献   
114.
The surface properties of porous silicon (PSi) evolve rapidly in phosphate-buffered saline. X-ray photoelectron spectra indicate the formation of a Si-OH and C-O enriched surface, which becomes increasingly hydrophilic with aging time. Multiscale stripe micropatterns of Si and PSi have been fabricated by means of a high-energy ion-beam irradiation process. These micropatterns have been aged in physiological conditions and used to analyze human mesenchymal stem cell (hMSC) adhesion. The actin cytoskeleton of hMSCs orients following the uniaxial micropatterns. In the wider Si stripes, hMSCs are dominantly located on Si areas. However, for reduced Si widths, adhesion is avoided on PSi by a split assembly of the actin cytoskeleton on two parallel Si areas. These results confirm that nanostructured Si-OH/C-O-rich surfaces with hydrophilic character are specially adapted for the creation of cell adhesion surface contrasts.  相似文献   
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BACKGROUND: M-mode recordings of the mitral annulus to measure the maximum ascending velocity during early diastole as an expression of maximum longitudinal relaxation velocity of the left ventricle (RVm) can be used as an index of left ventricular (LV) diastolic function. The purpose of this study was to determine the relationship of RVm with LV functional parameters in patients with heart failure, with N-terminal pro-brain natriuretic peptide (NT-proBNP) plasma levels, and with their functional classification. METHODS AND RESULTS: RVm was recorded in 97 patients by M-mode echocardiography. Patients were classified according to the New York Heart Association (NYHA) and the concentration of NT-proBNP was determined. Patients with ejection fraction (EF)>40 showed a significant correlation between RVm and mitral annulus motion (MAM), mitral flow propagation velocity, E/A, age, deceleration time (DT), and NT-proBNP. In patients with EF40, though its relationship with NT-proBNP both in patients with EF>or40 it is influenced only by age. RVm values showed a significant decrease in NYHA class II and III.  相似文献   
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118.

BACKGROUND AND PURPOSE

Metabolic and cardiovascular abnormalities accompanying metabolic syndrome, such as obesity, insulin resistance and hypertension, are all associated with endothelial dysfunction and are independent risk factors for erectile dysfunction. The purpose of the present study was to investigate the vascular effects of insulin in penile arteries and whether these effects are impaired in a rat model of insulin resistance and metabolic syndrome.

EXPERIMENTAL APPROACH

Penile arteries from obese Zucker rats (OZR) and their counterpart, lean Zucker rats (LZR), were mounted on microvascular myographs and the effects of insulin were assessed in the absence and presence of endothelium and of specific inhibitors of nitric oxide (NO) synthesis, phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK). Insulin-induced changes in intracellular Ca2+ concentration [Ca2+]i were also examined.

KEY RESULTS

OZR exhibited mild hyperglycaemia, hypercholesterolemia, hypertryglyceridemia and hyperinsulinemia. Insulin induced endothelium- and NO-dependent relaxations in LZR that were impaired in OZR. Inhibition of PI3K reduced relaxation induced by insulin and by the β-adrenoceptor agonist isoprenaline, mainly in arteries from LZR. Antagonism of endothelin 1 (ET-1) receptors did not alter insulin-induced relaxation in either LZR or OZR, but MAPK blockade increased the responses in OZR. Insulin decreased [Ca2+]i, a response impaired in OZR.

CONCLUSIONS AND IMPLICATIONS

Insulin-induced relaxation was impaired in penile arteries of OZR due to altered NO release through the PI3K pathway and unmasking of a MAPK-mediated vasoconstriction. This vascular insulin resistance is likely to contribute to the endothelial dysfunction and erectile dysfunction associated with insulin resistant states.  相似文献   
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Summary A prospective study of IgG and IgM isotypes of anticardiolipin antibodies (aCL) was performed in a series of 167 patients with various autoimmune diseases, including rheumatic and nonrheumatic disorders, and in a group of 100 healthy blood donors. The IgG aCL serum was regarded as positive if a binding index (BI) greater than 2.85 (3.77 SD) was detected and a BI greater than 4.07 (3.90 SD) was defined as positive for IgM aCL. Forty patients (24%) were found to be positive for IgG and/or IgM aCL. IgG aCL were detected in 23% of patients with systemic lupus erythematosus (SLE), in 9% with idiopathic thrombocytopenic purpura, in 7% with progressive systemic sclerosis, and in 6% with dermatomyositis-polymyositis. IgM aCL were present in 43% patients with primary biliary cirrhosis, in 33% with rheumatoid arthritis, in 22% with SLE, and in 8% with giant-cell arteritis. IgG aCL were found to have a significant association with thrombosis and thrombocytopenia, and IgM and aCL with haemolytic anaemia and neutropenia, in SLE but not in the other autoimmune diseases. The identification of these differences in the aCL isotype associations, depending on the autoimmune disorder, may improve the clinical usefulness of these tests.  相似文献   
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