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While the functional implications of AChE-T, PRiMA and ColQ have been firmly established, those of glypiated AChE remain uncertain. Insights into the physiological meaning of glycosylphosphatidylinositol (GPI)-linked AChE-H were gained by comparing nervous and non-nervous tissues for the amount of AChE mRNA variants they contained. PCR showed that AChE-T mRNA prevailed in the mouse brain, spinal cord, sciatic nerve and muscle, and AChE-H mRNA in the bone marrow and thymus, as well as in the human gut. The similar levels of AChE-T and AChE-H mRNAs in mouse liver and human kidney contrasted with the almost exclusive presence of catalytically active AChE-H in both organs. The absence of PRiMA mRNA in liver suggested that the tetramers made of AChE-T fail to bind to the cell membrane and are secreted due to the lack of PRiMA in non-nervous organs. In contrast, glypiated AChE-H is largely and lastingly bound to the cell membrane. Thus, non-synaptic glypiated AChE-H seems to be the counterpart of synaptic PRiMA-linked AChE-T, the former designed for clearing ACh waves, the latter for confronting ACh bursts, and both for helping to protect cells against the harmful effects of durable nicotinic and muscarinic activation.  相似文献   
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Obesity has been shown to be associated with increased left ventricular mass (LVM) and heart sympathetic activity even in nonhypertensive subjects. These factors are predictors of cardiovascular morbidity and mortality independent of other traditional risk factors. We evaluated the effect of losartan and spironolactone on LVM and heart sympathetic activity in prehypertensive obese subjects. A 16-week blinded randomized trial was performed in middle-aged men selected from a Health Public program. Anthropometric and clinical variables were measured at baseline and after losartan (50 mg/day; n=25) or spironolactone (25 mg/day; n=25) treatment. Heart sympathetic activity was evaluated with 60-min electrocardiograph monitoring, and spectral analysis was carried out. LVM was measured by echocardiography according to Devereux and Reicheck's formula indexed for body height (m2.7) to account for obesity. Anthropometric variables, systolic, and diastolic blood pressure levels decreased in both groups of treatment without statisticall difference between them. Losartan increased heart rate variability (from 70.0 to 82.3 ms; P=0.01), and decreased low frequency-high frequency index (from 6.6 to 4.9; P=0.001), and LVM (from 49.2 to 45.2 g; P=0.004). In the multiple regression analysis for factors associated with reduction in LVM; treatment with losartan, and decrease in SBP were the only factors included in the model (R2=0.60; P=0.003). To conclude losartan, but not spironolactone, decreased LVM and heart sympathetic overactivity in prehypertensive obese subjects after 16 weeks of treatment. Regression on LVM was associated with reduction on SBP levels.  相似文献   
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Considering the relevance of the migratory processes in Western societies, the attitudes toward organ donation after death are analyzed by means of a survey applied to a representative random sample of the resident immigrant population in Spain, comprising 1202 subjects (estimated margin of error of ± 2.88%, p = q, p < 0.05). Considered variables were disposition toward own organ donation, disposition toward deceased relatives' donation in different situations, arguments against donation, socio-demographic indicators, religious beliefs, social integration, and information about organ donation and transplantation. Predisposition to donate varies strongly across geographical origin and religious beliefs and also shows relationships with additional socio-demographic, social integration, and informative variables. In turn, the relationship between religious beliefs and attitude toward donation varies as a function of the degree of social integration. In Spain, the immigrant population is a heterogeneous collective that requires differential strategies to promote donation. Such strategies should be aimed at reinforcing the existing positive attitudes of citizens from West Europe and Latin America, and at familiarizing and informing about donation in citizens from the East, and at making specific efforts to break down the cultural and religious barriers toward donation in African citizens, with special emphasis on people of the Muslim faith.  相似文献   
87.
We have characterized the bisegmented genome of a novel double-stranded RNA (dsRNA) virus isolated from the plant pathogenic fungus Verticillium albo-atrum. We determined that its larger segment (dsRNA1) was 1747 base pairs in length and potentially encoded an RNA-dependent RNA polymerase of 539 amino acids, whereas the smaller segment (dsRNA2) was 1517 base pairs long and was predicted to encode a capsid protein of 435 amino acids. Homology searches and phylogenetic analysis confirmed that, as expected from its dsRNA banding profile, the identified virus was a new member of the family Partitiviridae, and we have therefore designated it V. a lbo- a trum partitivirus 1 (VaaPV1). This is the first report of a mycovirus identified in V. albo-atrum.  相似文献   
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Perinatal antiretroviral (ARV) exposure has been related to hyperlactatemia and lactic acidosis in infants born to HIV-infected mothers. Our objective was to determine the incidence of these conditions during the first year of life in uninfected infants born to HIV-infected mothers and compare the data with infants born to mothers with hepatitis C virus (HCV) infection. We investigated the relationships between hyperlactatemia and neurological and neurodevelopmental disorders by conducting a prospective, comparative cohort study (October 2004 to October 2007) consecutively including children of HIV- and HCV-infected mothers. Liver enzymes, pH, lactic acid, and plasma amino acids were determined at 1.5, 3, 6, and 12 months of life. Pathological hyperlactatemia was defined as lactate >2.1 mmol/liter together with alanine >475 μmol/liter. Seventy-nine patients (39 HIV-exposed patients and 40 unexposed patients) were included. Baseline maternal characteristics in the two groups were similar. Almost 90% of HIV-infected mothers received HAART during gestation, while 10.3% were given AZT monotherapy. Eight newborns received combined therapy and 31 received AZT-based monotherapy. Twelve patients (five exposed and seven nonexposed) had some neurological disorder, and four other patients (one vs. three) showed signs of neurodevelopmental delay, with no significant differences between the groups (p=0.34). Pathological hyperlactatemia was detected in 56.4% (95% CI 39.6-72.2) and 57.5% (95% CI 40.9-73.0) of patients, respectively (p=0.92), and this condition was more frequent in preterm children (p<0.05). ARV use during pregnancy and the neonatal period was not associated with pathological hyperlactatemia. The presence of hyperlactatemia was not associated with neurological or neurodevelopmental disorders. No association was established between the use of ARV agents and the development of hyperlactatemia or neurological disorders in HIV-exposed children during their first year of life.  相似文献   
90.
Increased levels of oxidative stress have been demonstrated in Preeclampsia in previous studies, but this finding has not been established in other hypertensive disorders in pregnancy (HDP). We measured different markers of lipid peroxidation and antioxidant defenses by spectrophotometry or enzymoimmunoanalysis in 339 pregnant women: 85 with gestational hypertension (GH), 88 chronic hypertension (CH), 104 Preeclampsia and 62 healthy pregnant control women (PCW). Lower activity of superoxide dismutase and higher levels of catalase were found in GH, CH and preeclampsia compared with PCW (964.4±116.5, 970.0±120.4, 971.2±137.5 and 1063.4±133.7?U?g(-1) Hb, P<0.001; and 313.0±71.7, 292.2±45.3, 297.1±47.2, 215.5±26.2?U?mg(-1) Hb, P<0.0001; respectively). Regarding the glutathione REDOX cycle, we found the following in GH, CH and preeclampsia compared with PCW: a decrease in its reduced form (2.6±0.6, 2.7±0.8, 2.7±0.9, 3.3±1.3?μmol?l(-1), P<0.003), a parallel increase in the oxidized form (185.6±68.9, 194.7±75.0, 184.3±78.3, 85.1±27.5?μmol?l(-1), P<0.0001) and an increment in glutathione peroxidase (85.9±22.0, 86.4±20.9, 82.1±23.5 and 77.2±19.7?U?g(-1) Hb, P<0.04) and glutathione reductase (6384.3±1261.9, 6724.6±1154.1, 6287.9±1399.9 and 6044.4±1208.4?mU?g(-1) Hb, P<0.01, respectively). Nitrites/nitrates were higher in patients with preeclampsia than in PCW (31.50±15.08, 26.80±8.39?μmol?l(-1), P<0.002). Although malondialdehyde and oxidized-LDL levels were similar among groups, free fatty acids were increased in every HDP (GH 514.6±194.6, CH 501.3±197.4, preeclampsia 555.2±230.1?μmol?l(-1)) compared with PCW (351.4±146.1?μmol?l(-1)), P<0.0001. Our results show an oxidation/reduction imbalance with an increase in oxidative stress coupled with a decreased capacity of antioxidant systems, not only in preeclampsia but also in every HDP.  相似文献   
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