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1.
A morphometric study of nucleolar organizer regions (NOR) was performed to analyze their distribution, volume, number and shape in the different strata of human normal oral mucosa epithelium and papilloma and in squamous cell carcinoma employing microphotographs of silver-stained paraffin sections. The different NOR-related parameters evidenced significant differences between normal mucosa, papilloma and squamous cell carcinoma. The functional polarity of normal mucosa epithelium and of papilloma is also evidenced in terms of NOR-related parameters. The discriminative value of certain NOR parameters was demonstrated.  相似文献   
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3.
Primary immunodeficiencies are inherited diseases characterized by impaired immune responses. In case of severe impairment of immunity bone marrow transplantation is the only therapeutic option. The molecular defect is known for several primary immunodeficiencies allowing prenatal diagnosis. This paper summarizes the clinical experience treating these pathologies by bone marrow transplantation.  相似文献   
4.
The cognitive profile of individuals with Down syndrome (DS) is known to be characterized by an impaired executive functioning, but inhibition-related processes have not been extensively examined in this setting. The aim of the present study was to investigate whether individuals with DS have any specific or general deficit in inhibitory processes. Tasks measuring prepotent response inhibition (the animal Stroop test), proactive interference (proactive interference task and intrusion errors), and response to distracters (directed forgetting task) were administered together with a working memory test to 19 individuals with DS and 19 typically developing (TD) children matched for mental age. Confirming previous findings, our results showed that the DS group performed less well in a verbal working memory task than the TD children. Analyzing our findings for the three inhibitory tasks yielded a picture of the DS children having a generalized difficulty in suppressing information that is irrelevant, or no longer relevant, to the goals of the task. These results suggest that DS is related not to specific, but rather to generalized inhibitory difficulties.  相似文献   
5.

Purpose  

We have little knowledge about the evolution of emphysema, and relatively little is understood about its evolution in relation to smoking habits. This study aims to assess the evolution of emphysema in asymptomatic current and former smokers over 2 years and to investigate the association with subjects’ characteristics. The study was approved by our Ethics Committee and all participants provided written informed consent.  相似文献   
6.
The effect of dopamine on human gastric and small intestinal interdigestive motility was investigated in 12 subjects. Intestinal motility was recorded by means of a four-lumen polyvinyl probe with four open tips located 15 cm apart, continuously perfused with distilled water. In each subject during the same study, after recording two consecutive spontaneous phase III of migrating myoelectrical complexes and when a phase II appeared, dopamine was infused intravenously twice in a dose of 5 g/kg/min for 15 min with an interval of 20 min between each infusion. In six subjects, the second dopamine infusion was preceded by a treatment with sulpiride (10 mg, intravenously, as bolus) or domperidone (10 mg, intravenously, as bolus), each considered a highly selective dopamine antagonist. The results show that dopamine stimulates duodenal motility producing a pattern similar to that observed in phase III of spontaneously occurring migrating myoelectrical complexes. The second dopamine infusion reproduced in all cases the same pattern of motility as observed during the first infusion. Sulpiride and domperidone prevented the effect of dopamine in all cases. It is therefore suggested that dopamine-induced duodenal motility may involve specific dopaminergic receptors.  相似文献   
7.
Influence of long-term diabetes on liver glycogen metabolism in the rat   总被引:1,自引:0,他引:1  
Diabetes acutely impairs the ability of the liver to synthesize glycogen. However, the effect of chronic diabetes on the glycogenic function of the liver is not known. We measured hepatic glycogen contents in streptozotocin (STZ)-diabetic rats 3 weeks or 9 months after the induction of diabetes, in the fed state and following a 24-hour fast. In the fed state, liver glycogen levels were markedly decreased in short-term diabetic animals (5.8 +/- 2.0 v 33.9 +/- 2.3 mg/g, P less than .001), but not in long-term diabetic rats (18.3 +/- 4.4 v 20.7 +/- 1.3 mg/g, P = NS) as compared with age-matched nondiabetic animals, despite comparable hyperglycemia (portal plasma glucose levels of 424 +/- 21 and 449 +/- 24 mg/100 mL, short- and long-term diabetics, respectively). In the fasted state, on the other hand, liver glycogen was depleted in acute diabetes (4.5 +/- 2.2 mg/g v 1.9 +/- 0.5 of control rats), but significantly increased in chronic diabetes (10.1 +/- 3.1 v 0.2 +/- 0.03 mg/g, P less than .001). The latter finding was confirmed by electron-microscopical examination of liver cells. Furthermore, the percentage of hepatic glycogen synthase in the active form (synthase a) was lower than normal in short-term diabetic rats and in old nondiabetic rats. In long-term diabetic animals, on the other hand, synthase a was significantly higher than in old controls (P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
In Crohn's disease, prednisone is believed to be ineffective for relapse prevention. Because all patients with Crohn's Disease Activity Index lower than 150 and with some altered lab tests (erythrocyte sedimentation rate, C-reactive protein, alpha-1-acid glycoprotein, alpha-1-acid antitrypsin, and white blood cell count) had a clinical relapse in 18 months of follow-up, we tried to ascertain whether methylprednisolone could reduce the risk of clinical relapse in such patients. Eighteen patients were included in a controlled study against placebo. Nine patients were treated with methylprednisolone at a dosage of 0.25 mg/kg daily for a period of 6 months; treatment was discontinued if disease relapsed or if lab tests were normalized. During the steroid treatment, 1 of 9 patients showed a clinical relapse; in 7, the normalization of lab tests was obtained; in 5 of these 7 patients a relapse occurred within 1 month after the suspension of the treatment; in 1 patient, lab tests remained altered. In those 9 patients on placebo, relapses occurred in 7. We conclude that methylprednisolone was effective in the prevention of relapses for patients in clinical remission but with altered lab tests.  相似文献   
9.
Anorectal motility and gastrointestinal transit time were studied in 25 patients complaining of non-organic constipation. Colonic pain was reported by 14 patients, it was absent in the remaining 11. The group with painful constipation was composed of four men and 10 women and age onset of the symptom was 22.1 +/- 5.1 years. The other group was composed only of women and painless constipation was reported to have begun at 7.9 +/- 2.2 years previously. In the group presenting painful constipation higher values of the anal maximum resting pressure, of the amplitude of the rectoanal inhibitory reflex, lower values of sensation threshold, need to evacuate, maximum tolerable volume were recorded, in comparison with those registered in the painless constipation group. All these differences were significant. In the latter group the total transit time was always very slow (186.0 +/- 4.7 h), while it was quite variable in the other group, so that the mean was in the normal range (79.0 +/- 10.0 h). The data show that two different patterns of motor abnormalities can be recognised in constipated patients. The presence of colonic pain can suggest the characteristics of the underlying motor abnormality.  相似文献   
10.
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