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The rise in popularity of hyaluronic acid (HA) dermal filler injection has caused an exceptional increase in the number of cases of reported irreversible blindness. Here, we reported a case of ischemic optic neuropathy and ophthalmoplegia following subcutaneous HA filler injection with complete visual recovery. A 31-year-old Chinese woman presented with sudden onset of right monocular visual impairment associated with diplopia. Patient had received a hyaluronic acid-containing ?ller injection for nasal dorsum augmentation twelve hours prior to presentation. Visual acuity of the right eye was counting finger. A right relative afferent pupillary defect was demonstrated with ophthalmoplegia. Humphrey visual field test disclosed a right inferior altitudinal field defect with impairment of colour vision. Computed tomography of the orbit revealed mild enlargement of the right medial and inferior recti muscles. Our patient showed a tremendous improvement of vision after a subcutaneous hyaluronidase injection with complete visual recovery within 2 weeks.  相似文献   
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Summary To define the glucose to insulin dose-response relationship before the onset of diabetes, we studied 22 nondiabetic co-twins of patients with Type 1 (insulin-dependent) diabetes mellitus and nine control subjects. All had intravenous glucose tests at 0.02, 0.1 and 0.5 g/kg and were followedup prospectively for at least 6 years. Seven twins developed diabetes a mean of 7 months later; the remaining 15 are now unlikely to develop diabetes. The seven pre-diabetic twins had higher fasting insulin levels than control subjects (4.2±2.0 vs 1.8±1.8 nmol/l; p<0.05); but lower glucose clearance (1.0±0.5 vs 1.9±0.7 %/min; p<0.05), first phase insulin response at 0.5 g/kg (21.1±23.2 vs 143±50 nmol/l; p<0.0001), and total insulin responses at 0.1 g/kg (p<0.05) and 0.5 g/kg (p<0.00005). Using a curve-fitting programme, the normal glucose to insulin relationship was lost in prediabetic twins who had lower coefficient of determination (R2) than control subjects (p<0.01). In contrast, 15 low-risk twins and their nine control subjects had similar fasting glucose and insulin levels, glucose clearance, R2 and insulin secretory responses to different glucose loads. The positive predictive values of subnormal R2 and subnormal first phase insulin response were 67 % and 58 % respectively. These observations demonstrate an altered glucose to insulin dose-response relationship and loss of maximum insulin secretory response to glucose before the onset of Type 1 diabetes.  相似文献   
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Repetitive nerve stimulation (RNS) is a simple and rapid method for evaluation of neuromuscular transmission defects. Although the effect of exercise in conjunction with RNS is well recognized, it has not been standardized in actual patient and control groups. In a prospective study over a period of 1 year, the authors evaluated the effect of exercise in conjunction with RNS in comparison with conventional 3-Hz RNS at rest in the clinical setting. Fifty-four patients who were referred for possible neuromuscular transmission disorders, in addition to 35 healthy control subjects, were studied. Amplitude and area decremental responses with RNS at rest and after 20 seconds of maximal exercise at 1-minute intervals up to 3 minutes were evaluated. The use of RNS with exercise resulted in additional diagnostic yield of up to 36.4% compared with conventional 3-Hz RNS at rest. The standardized use of exercise with RNS is advocated for increasing its diagnostic yield in the neurophysiologic laboratory.  相似文献   
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The effect of the antineoplastic immunosuppressive alkylating agent cyclophosphamide (CPhA) on the modification of the carcinogen-metabolizing capacity was studied in vivo in mouse liver microsomes at different durations of treatment, from one to six consecutive days. The in vitro effect of increasing concentrations of the drug upon this enzyme system was also investigated. Following the administration of CPhA, a significant time-dependent decrease was observed in the activity of the low substrate level of the hepatic microsomal N-nitrosodimethylamine demethylase (NDMAdII). The high substrate level of the enzyme (NDMAdII) also exhibited a similar decrease which was not a subject for the treatment intervals where the greatest decrease (-60%; p<0.05) emerged at day 3 of the administration-point. The activity of the aryl hydrocarbon (benzo(alpha)pyrene) hydroxylase (AHH) revealed a significant increase at the single dose of CPhA, while at the repeated dose treatment (for 3 days) no alteration was noticed in the enzyme activity. This figure of expression in AHH was reversed to a significant inhibition at the 6 day-repeated dose, the time-point at which an almost identical effect was also observed in the hepatic content of cytochrome P450. The alterations in the metabolism of NDMA and benzo(alpha)pyrene which had been seen in the in vivo assays was further confirmed by the results of the in vitro experiment.  相似文献   
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Glutamic acid decarboxylase (GAD) is the enzyme responsible for the synthesis of gamma-aminobutyric acid (GABA). GAD has been identified as a 64-kDa antigen expressed in pancreatic beta-cells, to which autoantibodies are generated prior to the onset of type 1 (insulin-dependent) diabetes mellitus. GAD may therefore be an initiating factor in beta-cell destruction. We administered baclofen, a GABA-B receptor agonist, to non-obese diabetic (NOD) mice in an attempt to down-regulate GAD expression and thereby reduce the incidence of diabetes. Twenty-four female NOD mice were given baclofen in their drinking water at a final dose of 50 mg/kg body weight daily from weaning to 30 weeks of age. Twentyfour sex-and litter-matched mice were used as controls. At 30 weeks there was no difference in the incidence of diabetes in the treated group compared with the controls. However, there was a significant delay in the onset of diabetes in the treated group (P<0.001, parallelism test). The degree of insulitis and the GAD activity in the pancreas per mg of protein were unchanged by baclofen treatment with respect to controls. These results suggest that baclofen may be effective in delaying diabetes onset in NOD mice by stimulating GABA activity, as this neurotransmitter, localised in the islets, may modulate insulin secretion and the antigen expression associated with it.  相似文献   
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We report here a rare case of bilateral pure gonadoblastoma which accounts for only 0.2% of all ovarian tumours seen at Universiti Kebangsaan Malaysia from 1980 to 1987. This tumour occurred in an 18 year old Chinese "female" who presented with primary amenorrhoea. Examination showed a phenotypic female with poorly developed external gentalia. Exploratory laparotomy revealed a hypoplastic uterus, rudimentary fallopian tubes and streak gonads. Histological examination of the gonads showed a mixed tumour comprising large germ cells and smaller sex cord derivatives arranged in characteristic nests or islands containing hyaline material.  相似文献   
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Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.  相似文献   
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