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61.
Basic autonomic nervous function was evaluated in patients with neurocardiogenic syncope (NCS). Atropine, isoproterenol, propranolol, phenylephrine, and phentolamine were administered successively, and parasympathetic nerve activity and beta- (and alpha-) activity, sensitivity, and secretion of the sympathetic nerve were determined in patients with NCS and control subjects. In patients with NCS, beta- and alpha- sensitivity were higher and beta-activity and beta- and alpha-secretion lower than in control subjects. In patients with NCS, the increased basic beta-sensitivity may contribute to induce strong cardiac contractions and augment ventricular mechanoreceptor response, and a compensatory state against diminished neuronal sympathetic activity is suggested by the increased alpha-sensitivity.  相似文献   
62.
We document here the first case of bulimia nervosa associated with primary hyperparathyroidism. The binge eating and self-induced vomiting that occurred for more than 10 years disappeared completely after the surgical cure of primary hyperparathyroidism. Depressive and anxiety symptoms also improved dramatically. The possible influence of derangement in calcium metabolism on the neurobiochemical mechanism of bulimia nervosa is discussed.  相似文献   
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Intercellular adhesion molecule-1 (ICAM-1) plays an important role in leukocyte migration from the circulation and intervention at sites of inflammation. We investigated the effects of various types of exercise on circulating levels of soluble ICAM-1 (sICAM-1) in normal healthy male adults. Plasma concentrations of sICAM-1 were measured before and after bicycle ergometer exercise at intensity of 80% maximal oxygen consumption ( ) (16 min), 42 km endurance running and 30-min downhill running at intensity of ventilation threshold (VT). The plasma sICAM-1 level increased 1 day after the endurance running (12%) and downhill running (14%), but not after ergometer exercise. Plasma C-reactive protein (CRP) and creatine kinase (CK) concentrations also increased 1 day after running. Our data suggest that exercise associated with muscle damage and/or inflammation results in increased levels of plasma sICAM-1. The physiological significance of post-exercise high plasma sICAM-1 levels is not clear at this stage, but changes in plasma sICAM-1 may reflect the status of the immune system. Electronic Publication  相似文献   
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BACKGROUND AND METHODS: Although hyperbaric oxygen therapy is clinically used for the treatment of several types of ischemic brain injury, few basic animal studies are available that provide a rationale for this therapy for complete global brain ischemia. Therefore, we investigated the effect of hyperbaric oxygen therapy on neurologic recovery after 15-min complete global cerebral ischemia in a canine model. Complete global ischemia was induced in 19 dogs by occlusion of the ascending aorta and the caval veins. Nine dogs were randomized to treatment with hyperbaric oxygenation (3 atmospheres absolute, 100% oxygen for 1 hr) at 3, 24, and 29 hrs after ischemia under spontaneous respiration, while the other ten dogs served as the control group without hyperbaric oxygen therapy (group C). Neurologic recovery was evaluated based on the electroencephalogram (EEG) activity score (1 = normal; 5 = isoelectric) and the neurologic recovery score (100 = normal; 0 = brain death) over a 14-day postischemic period. RESULTS: The survival rates were 3/10 (30%) in the control group vs. 7/9 (78%) in the group treated with hyperbaric oxygen (p < .05). Over the 14-day postischemic period, the best (lowest) EEG scores of each dog were significantly (1.7 +/- 0.2 vs. 2.9 +/- 0.3; mean +/- SE, p < .01) lower in the hyperbaric oxygen-treated group. The best neurologic recovery scores of each dog were significantly (69 +/- 6 vs. 48 +/- 5; mean +/- SE, p < .05) higher in the treated animals. The number of dogs that recovered to a neurologic recovery score of > 65 (assessed as a slight disability) were 1/10 in the control group and 6/9 in the group treated with hyperbaric oxygen (p < .02). CONCLUSIONS: Hyperbaric oxygen therapy performed in the early postischemic period accelerated neurologic recovery and improved the survival rate in dogs after 15-mins of complete global cerebral ischemia.  相似文献   
67.
The cerebral protective effects of MgSO4 after complete global brain ischemia were evaluated with EEG, evoked potentials (EP) and the neurological recovery score (NRS) in the dog. Complete global brain ischemia for 15 min was achieved by occluding the ascending aorta and the caval veins. The MgSO4 group (N=7) were injected with a 10% MgSO4 solution and the control group (N=7) were administered a normal saline intravenously from the beginning of the resuscitation to 48 h after ischemia. The EEG grades (1=normal, 5=flat) in the control group and the MgSO4 group were 3.9±0.1 (mean ±SEM) and 3.7±0.3, and the EEG-EP scores (6=normal, 0=serious deterioration) were 2.6±0.4 and 2.7±0.4 4h after ischemia, respectively. The 7-day survival rates for ischemia were equal in both groups (5/7:71%). The NRSs (0=death, 100=normal) in the control group and the MgSO4 group were 50±3 (n=7) and 43±9 (n=7) on the 3rd day after ischemia, and were 56±5 (n=5) and 42±12 (n=5) on the 7th day. The differences between the two groups were not significant. We conclude that MgSO4 administered after ischemia has no beneficial effects on the recovery of EEG, EP and the NRS after 15 min of complete global brain ischemia in the dog.  相似文献   
68.
In the course of our screening for microbial compounds which possessed inhibitory activities against biosynthesis of cholesterol from mevalonate, we isolated four new compounds from the cultural broth of Streptomyces sp. A7361. They are structurally related to, but distinct from chlorothricin.  相似文献   
69.
As bacteria continue to develop resistance toward current antibiotics, we find ourselves in a continual battle to identify new antibacterial agents and targets. We report herein a class of boron-containing compounds termed borinic esters that have broad spectrum antibacterial activity with minimum inhibitory concentrations (MIC) in the low microgram/mL range. These compounds were identified by screening for inhibitors against Caulobacter crescentus CcrM, an essential DNA methyltransferase from gram negative alpha-proteobacteria. In addition, we demonstrate that borinic esters inhibit menaquinone methyltransferase in gram positive bacteria using a new biochemical assay for MenH from Bacillus subtilis. Our data demonstrate the potential for further development of borinic esters as antibacterial agents as well as leads to explore more specific inhibitors against two essential bacterial enzymes.  相似文献   
70.
BACKGROUND: The immune system declines in efficiency with advancing age, making the elderly less resistant to pathogenic microorganisms. Upper respiratory tract infection (URTI) is a common illness. Recent studies have shown that suppression of secretory immunoglobulin A (SIgA) is associated with increased incidence of URTI. OBJECTIVE: To assess the effect of exercise on salivary SIgA in elderly subjects. METHODS: Forty five elderly subjects (18 men, 27 women; mean (SD) age 64.9 (8.4) years) performed both 60 minute resistance and 60 minute moderate endurance training a week for 12 months. Saliva samples were obtained before training, and at four and 12 months during the training period. Salivary SIgA concentrations were measured by enzyme linked immunosorbent assay, and the SIgA secretion rate was calculated. RESULTS: SIgA concentrations before training, and at four and 12 months during training were 24.7 (14.4), 27.2 (14.2), and 33.8 (18.5) micro g/ml respectively. SIgA secretion rates were 29.5 (26.0), 33.8 (27.2) and 46.5 (35.1) micro g/min respectively. The results indicate that both the concentration and secretion rate of SIgA significantly (p<0.01) increased during 12 months of exercise in these elderly subjects. CONCLUSION: Regular moderate exercise seems to enhance mucosal immune function in elderly subjects.  相似文献   
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