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71.
The investigation was undertaken to elucidate the specific features of cerebral blood flow in acute brain injury (BI) in relation to its severity. Cerebral circulation (CC) was studied in 83 patients aged 5 to 64 years in the acute period of BI. The authors estimated the consciousness by the Glasgow coma scale and CC from the mean linear blood flow velocity (LBFV) in both middle cerebral arteries (MCA). To calculate the hemispheric index (HI), blood flow was examined in the extracranial portion of the ipsilateral internal carotid artery. The traumatic lesion substrate was verified by computed tomography and magnetic resonance imaging. Intracranial and cerebral perfusion pressures were continuously monitored in 39 patients. The outcomes of BI were assessed by means of the Glasgow outcome scale. In accordance with the values of LBFV, all the patients were divided into 3 groups: 1) patients in whom MCA LBFV throughout the acute period of BI remained within the range of normal or low values (30-70 cm/sec); 2) those in whom MCA LBFV ranged from 80 to 120 cm/sec at a HI of less than 3.0; 3) those with vasospasm in whom MCA LBFV was more than 120 cm/sec at a HI of more than 3.0. Analysis of the studies revealed that despite the same consciousness impairments, the magnitude of CC disorders was appropriate to the severity of brain lesions in all three groups. At the same time severe and mixed brain lesions as intracranial hematomas, type 3 contusion foci, and profuse subarachnoidal hemorrhages were attended by the development of unilateral or bilateral vasospasm of MCA. In addition, the low CC values mainly associated with prehospital overall cerebral hypoxia were ascertained to be a poor factor of the outcome of BI. The best results of treatment for BI are achieved in moderate CC disorders as a moderate LBFV increase.  相似文献   
72.
Electrophysiological studies (EPS) are now being performed in district general hospitals (DGH) in the UK. In order to audit our results, a prospective database was established for all patients undergoing EPS and radiofrequency (RF) ablation at Eastbourne District General Hospital, East Sussex. Between 1 January 1997 and 1 July 2000, 300 EPS procedures were performed, resulting in 155 RF ablations. The average RF ablation procedure time was 119.3 minutes with an average fluoroscopy time of 19.1 minutes. Cost per RF ablation procedure was £1166.79 excluding use of facilities, pacemaker devices, medical nursing and radiography staffing costs. The overall success rate for RF ablation was 93.6% with a major complication rate of 0.6%, a total complication rate of 3.9% and no associated mortality. We have shown that RF ablation can be performed safely, effectively and economically in a DGH setting with a high rate of success and a low complication rate.  相似文献   
73.
AIM: To develop screening diagnosis of gluten enteropathy (GEP), indications to administration of glucocorticoid hormones and objective criteria of effective treatment. MATERIAL AND METHODS: Clinical, immunological (antibodies-Abs to alpha-gliadin, reticulin and endomisium) examinations, enterobiopsy with morpho- and stereometry of small intestinal mucosa were made in 200 GEP patients. The examination was repeated 6 months to 5 years and later after the discharge from the hospital. RESULTS: Mean values of Abs to alpha-gliadin was 6 times higher than normal values. Positive titers of Abs to endomisium and reticulin were in 100 and 87.5% patients, respectively. Formed stool was registered 1.5 times more frequently, polyfecalia occurred 2.5 times less frequently, hypovitaminosis and trophic disorders were relieved 3 times more frequently, malabsorption syndrome reduced in patients given prednisolone vs those untreated with it. CONCLUSION: Screening diagnosis of GEP may be based on Abs tests to alpha-gliadin, reticulin and endomisium. Improvement of clinical condition of GEP patients can be stated by decreased diarrhea, polyfecalia and malabsorption symptoms. The treatment efficacy may be judged by clinical improvement, recovery of morphological structure of small intestinal mucosa, normalization of concentration of Abs to alpha-gliadin, reticulin, endomisium. Administration of prednisolone provides more complete and rapid rehabilitation of the patients.  相似文献   
74.
The chemopreventive activity of the highly specific nonsteroidal aromatase inhibitor, vorozole, was examined in the methylnitrosourea (MNU)-induced rat model of mammary carcinogenesis. Various doses of vorozole (0.08-1.25 mg/kg body wt/day) were administered daily (by gavage) to female Sprague-Dawley rats starting at 43 days of age. Seven days later, the rats were given a single i.v. dose of MNU (50 mg/kg body wt). Rats were continually treated with vorozole until the end of the experiment (120 days post-MNU). Vorozole caused a dose dependent inhibition of mammary cancer multiplicity. The highest dose of vorozole (1.25 mg/kg body wt/day) decreased cancer multiplicity by approximately 90%, and simultaneously decreased cancer incidence from 100 to 44%. The next two highest doses of vorozole (0.63 and 0.31 mg/kg body wt/day) inhibited MNU-induced mammary cancer multiplicity by 70-80%. Even the two lowest doses of vorozole (0.16 and 0.08 mg/kg body wt/ day) decreased cancer multiplicity -50%. Serum level determinations were performed on a variety of endpoints at either 4 or 24 h following the last dose of vorozole. Insulin-like growth factor (IGF)-1 levels were slightly, but significantly, increased by vorozole treatment. Vorozole induced striking increases in serum testosterone levels at 4 h at all the dose levels employed. Testosterone levels were significantly elevated over controls at 24 h in rats given the lower doses of vorozole (0.08-0.31 mg/kg body wt/day), but were significantly lower than in rats administered the higher doses of vorozole (0.63 or 1.25 mg/kg body wt/ day). This result presumably reflects the limited half- life of vorozole in rats. In a second series of experiments, the effects of limited duration of dosing with vorozole (2.5 mg/kg body wt/day) or intermittent dosing with vorozole were determined. Treatment of rats with vorozole for limited time periods, from 3 days post-MNU administration until 30 or 60 days post-MNU treatment, resulted in significant delays in the time to appearance of palpable cancers. However, these limited treatments did not greatly affect the overall incidence or multiplicity of mammary cancers when compared with the MNU controls at the end of the study (150 days post-MNU). Finally, the effects of intermittent dosing with vorozole (2.5 mg/kg body wt/day) were examined. Rats were administered cycles of vorozole daily for a period of 3 weeks followed by treatment with the vorozole vehicle for the next 3 weeks (total of four cycles). Although this intermittent treatment did inhibit the appearance of new tumors during each of the periods that vorozole was administered, it did not cause regression of palpable cancers.   相似文献   
75.
A comparative study was made of the efficacy of various types of deliberate modification of the leukemogenic activity of a transplantable line of bone marrow cells obtained from animals infected with Rauscher leukemia virus. Treatment of the leukemic cells with neuraminidase, or culturing them at a supraoptimal temperature led to complete loss of their leukemogenic activity, as shown by survival of 100% of the experimental animals and the absence of splenomegaly. Meanwhile, treatment of the cells with concanavalin A and 5-bromodeoxyuridine delayed the development of splenomegaly and lowered the mortality among the recipient animals by 70 and 20%, respectively. The results suggest that these methods of action on leukemogenic cells can be used in order to obtain material for subsequent immunization.Department of Virology, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. D. Solov'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 448–449, April, 1977.  相似文献   
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78.
The incidence and prevalence of end-stage renal disease (ESRD) continues to increase, especially in the elderly population. The role of renovascular disease in contributing to ESRD is still not well defined. The objective of this study was to determine the utility of gadolinium (Gd)-enhanced magnetic resonance angiography (MRA) in evaluating elderly patients with renal insufficiency for renal artery stenosis (RAS). A 7-month prospective study conducted in a tertiary referral center evaluated 40 consecutive patients with progressive renal insufficiency (18 men and 22 women; mean age, 70 +/- 5.6 [standard deviation] years) and high clinical suspicion for renovascular disease with Gd-enhanced MRA. Digital subtraction angiography (DSA) was obtained in only those patients with significant RAS detected by MRA. Twelve patients had significant RAS. Six of these patients had percutaneous transluminal renal angioplasty (PTRA), five patients had renal artery bypass surgery, and one patient had a stent placed after PTRA. Seventy-eight renal arteries were satisfactorily evaluated by MRA. Twenty-two renal arteries were evaluated by both MRA and DSA. Of the 12 significant stenoses detected by the MRA, 11 were confirmed by DSA and 1 was confirmed at the time of surgical revascularization. It is concluded that Gd-enhanced MRA is a useful test for the evaluation of RAS in patients with compromised renal function.  相似文献   
79.
Immune status has been studied in the course of intensive care in 48 patients. It has been established that hemosorption may enhance already existing changes in immune homeostasis in patients with sepsis. Therefore, immunostimulating therapy with tactivin and group B vitamins (B1, B6, B12) or ultraviolet (UV) blood irradiation in combination with group B vitamins administration have been included into therapy. Simultaneous use of tactivin, group B vitamins and UV blood irradiation was not advisable due to reduction of immunostimulating effect. Consecutive use of the immunity-stimulating methods seems expedient.  相似文献   
80.
The review of the literature data and the authors' data on interferon action inhibitors being one of the components of interferon system is presented. The methods of the production of various types of interferon action inhibitors, their characteristics and the main differences between them are described. The possible mechanisms of inhibitors' actions are considered. It was shown that the study of interferon action inhibitors is important in both the theoretical and practical aspects.  相似文献   
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