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91.
The study aimed at determining the effect of melatonin on the activity of protective antioxidative enzymes in the heart and of lipid peroxidation products in the course of intoxication with doxorubicin (DOX). The rats were categorized into four groups, receiving: 0.9% NaCl i.p. (NaCl control); melatonin [20 mg/kg body weight (b.w.)] s.c. (control Mel); DOX (2.5 mg/kg b.w.) i.p.; melatonin plus DOX in doses as above. All the substances were administered once in a week for four consecutive weeks. Homogenates of heart tissue were examined for activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), levels of reduced glutathione (GSH) and of lipid peroxidation indices (MDA + 4-HDA). Administration of melatonin alone did not induce alterations in levels of MDA + 4-HDA, GSH, or in activity of GPx, SOD or CAT, as compared to the group receiving 0.9% NaCl. GSH levels decreased following DOX but remained at normal levels following DOX and melatonin. The level of MDA + 4-HDA increased following DOX, as compared with the control, a change prevented by the combination of DOX + melatonin. Activities of GPx, SOD and CAT were higher in groups receiving DOX and/or DOX plus melatonin than in control groups. Activity of CAT and the level of GSH in the group receiving DOX plus melatonin were significantly higher than in the group intoxicated with DOX alone. The obtained results demonstrate that, when given in parallel with DOX, melatonin protects cardiomyocytes from damaging effects of the cytostatic drug (reflected by the levels of MDA + 4-HDA). The protective effect resulted, in part from the augmented levels of GSH and from stimulation of CAT activity by melatonin in cardiomyocytes subjected to the action of DOX.  相似文献   
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Rumination, repetitively thinking about the causes, consequences, and one''s negative affect, has been considered as an important factor of depression. The intrusion of ruminative thoughts is not easily controlled, and it may be useful to visualize one''s neural activity related to rumination and to use that information to facilitate one''s self‐control. Real‐time fMRI neurofeedback (rtfMRI‐nf) enables one to see and regulate the fMRI signal from their own brain. This proof‐of concept study utilized connectivity‐based rtfMRI‐nf (cnf) to normalize brain functional connectivity (FC) associated with rumination. Healthy participants were instructed to brake or decrease FC between the precuneus and the right temporoparietal junction (rTPJ), associated with high levels of rumination, while engaging in a self‐referential task. The cnf group (n = 14) showed a linear decrease in the precuneus‐rTPJ FC across neurofeedback training (trend [112] = −0.180, 95% confidence interval [CI] −0.330 to −0.031, while the sham group (n = 14) showed a linear increase in the target FC (trend [112] = 0.151, 95% CI 0.017 to 0.299). Although the cnf group showed a greater reduction in state‐rumination compared to the sham group after neurofeedback training (p < .05), decoupled precuneus‐rTPJ FC did not predict attenuated state‐rumination. We did not find any significant aversive effects of rtfMRI‐nf in all study participants. These results suggest that cnf has the capacity to influence FC among precuneus and rTPJ of a ruminative brain circuit. This approach can be applied to mood and anxiety patients to determine the clinical benefits of reduction in maladaptive rumination.  相似文献   
94.
IntroductionThe incidence of hepatitis E virus (HEV) infections in Poland is largely unknown. This study aimed to describe seroprevalence of markers of HEV infection among patients with immunodeficiency of diverse etiology and patients with advanced chronic liver diseases.Material and methodsFour hundred fifty patients were enrolled; among them, 180 persons were solid organ transplant recipients, 90 patients were HIV-infected and 180 persons had confirmed liver cirrhosis of different etiology. Serum anti-HEV-IgG, IgM antibodies and HEV-antigen were detected by ELISA (Wantai, China).ResultsIn the group of transplant recipients, serum anti-HEV-IgG antibodies were detected in 40.6%, IgM in 1.1% and HEV-Ag in 2.8% of subjects. In the HIV-infected population 37.7% had anti-HEV-IgG, 1.1% had anti-HEV-IgM and none had HEV-Ag. Among patients with advanced chronic liver diseases the highest prevalence of anti-HEV-IgG was recorded in alcohol-related liver cirrhosis (52.1%) (p = 0.049). In the population of all liver cirrhotics anti-HEV-IgG seroprevalence was 48.3%, anti-HEV-IgM seroprevalence was 5.0% and HEV-Ag seroprevalence was 1.7%. Older age and male gender were significant risk factors associated with increased anti-HEV-IgG prevalence, p = 0.0004 and p = 0.02, respectively.ConclusionsIn this large cohort a high seroprevalence of anti-HEV-IgG was detected in comparison to other European countries, with the highest rates in patients with alcoholic liver disease and in transplant recipients.  相似文献   
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The inhibitory effects of intravenous secretion on the gastric acid responses to a meal and to pentagastrin were studied in seven duodenal ulcer patients.

A test meal of 10% peptone adjusted to pH 5·0 was introduced into the stomach and the Fordtran and Walsh method was used to measure the gastric acid output by monitoring the rate at which a solution of 0·3 M sodium bicarbonate had to be added to keep the pH of the gastric content constant at the value of 5·0. A constant dose of secretin (1 U/kg-hr) significantly depressed the serum gastrin response to a meal and produced an inhibition of acid secretion by about 70% of the control level. Secretin inhibited the acid response induced by pentagastrin by about 60% and simultaneously provoked a pancreatic bicarbonate output sufficient to neutralize about 60% of the gastric acid output to pentagastrin. We conclude that secretin is a strong inhibitor of gastric secretion in duodenal ulcer patients induced by a meal and by pentagastrin.

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98.
The frequent association of thyroid and parathyroid disorders has been reported. Most commonly, hyperthyroidism may coexist with hypercalcemia, but the latter is successfully treated when euthyroidism is achieved. However, the concomitant hyperthyroidism with primary hyperparathyroidism is of a rare occurrence. Moreover, it may frequently go unrecognized. In this paper we report a case of a patient with hypercalcemia due to PTH--secreting parathyroid adenoma associated with hyperthyroidism due to toxic nodular goiter. This case demonstrates the dramatic outcome of those two coexisting disorders. We point out that in patients with primary hyperparathyroidism thyroid function test should always be carried out. A proper, first-line treatment of hyperthyroidism will prevent the deterioration of primary hyperparathyroidism course, and thus surgical parathyroid treatment may safely be introduced.  相似文献   
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Aim. To investigate whether adolescent online gaming time and the additive effect of gaming motives were associated with depressive, musculoskeletal, and psychosomatic symptoms. The hypothesis was that adolescents who engage in online gaming with escape motives and increased online gaming time have higher probability for depressive, musculoskeletal, and psychosomatic symptoms compared to adolescents with other online gaming motives and/or less online gaming time.Method. An anonymous and voluntary questionnaire was completed during class hours by 7,757 Swedish adolescents aged 13–18 years. The questionnaire included demographic background, gaming habits, and depressive, musculoskeletal, and psychosomatic symptoms.Results. It was found that increased online gaming time during weekdays increased the probability of having depressive, musculoskeletal, and psychosomatic symptoms. However, these relations with time spent gaming were further explained by online gaming motives. Weekday online gaming for more than five hours a day, in combination with escape motives, was associated with an increased probability of depressive symptoms (odds ratio (OR) 4.614, 95% CI 3.230–6.590), musculoskeletal symptoms (OR 2.494, 95% CI 1.598–3.892), and psychosomatic symptoms (OR 4.437, 95% CI 2.966–6.637). The probability of ill health decreased when gaming was for fun or had social motives.Conclusion. Excessive gaming time and escape motives were found to be associated with increased probability of ill health among adolescents. Gaming motives may identify gamers in need of support to reduce unhealthy gaming behaviour as well as identify individuals at risk for ill health.  相似文献   
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