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141.
A 46-year-old man ingested approximately 50 ml of a plastic resin catalyst He developed persistent gastrointestinal bleeding, renal and hepatic failure, pneumonitis, and septicemia, and died four weeks later. Autopsy revealed chronic esophagitis and gastritis with massive intraluminal gastrointestinal hemorrhage. This case emphasizes the potential danger of ingestion of such substances.  相似文献   
142.
The aim of this study was to estimate the 1-year prevalence of migraine and the degree of the association of migraine with some sociodemographic characteristics of a representative sample of the adult population of Brazil. This was a cross-sectional, population-based study. Telephone interviews were conducted on 3848 people, aged 18–79 years, randomly selected from the 27 States of Brazil. The estimated 1-year gender- and age-adjusted prevalence of migraine was 15.2%. Migraine was 2.2 times more prevalent in women, 1.5 times more in subjects with > 11 years of education, 1.59 times more in subjects with income of < 5 Brazilian Minimum Wages per month, and 1.43 times more in those who do not do any physical exercise. The overall prevalence of migraine in Brazil is 15.2%. Migraine is significantly more prevalent in women, subjects with higher education, with lower income, and those who do not exercise regularly, independently of their body mass index.  相似文献   
143.
OBJECTIVE: To determine whether echocardiography affects the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients suspected of having mitral valve prolapse (MVP). DESIGN: Retrospective review of echocardiograms and clinical records. SETTING: Military tertiary care hospital. PATIENTS: 127 patients with clinically suspected MVP (105) or incidentally discovered MVP (22). MAIN RESULTS: Beta blockers were used more often in patients with suspected MVP and positive echocardiograms (45%) than in patients with normal echocardiograms (13%, p less than 0.001). Bacterial endocarditis prophylaxis was recommended more often in patients with suspected MVP and positive echocardiograms (65%) than in patients with normal echocardiograms (11%, p less than 0.001). Presence or absence of a murmur did not influence the decision to recommend bacterial endocarditis prophylaxis. Patients in whom MVP was incidentally discovered were unlikely to receive either beta blockers or the recommendation for bacterial endocarditis prophylaxis. CONCLUSIONS: The results of echocardiography affect the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients with suspected MVP.  相似文献   
144.
Comorbidity weights have become an important tool in longitudinal outcome studies. They should be tailored toward the population and the disease state under investigation.
OBJECTIVES: The objectives of the study were to develop and validate a comorbidity index for ischemic stroke patients for use in longitudinal studies.
METHODS: A 5-year retrospective review of all Georgia Medicaid claims data from 1990 to 1994 was used to detect first time ischemic stroke patients. Ischemic strokes were defined by three ICD-9-CM code series (433.XX, 434.XX, and 436.XX). Comorbid conditions were measured from all claims submitted within 12 months prior the first ischemic stroke event. Half of the stroke cohort was randomly selected, and multivariate logistic regression was used to derive a mortality stroke-specific weighted-index, controlling for age and gender. The Charlson and stroke-specific indexes were then tested on the second half of the stroke cohort for their ability to predict risk of death.
RESULTS: We identified 3,784 ischemic stroke patients with a mean age of 65 years (range 40 B 102). Of all patients, 40% died within the 3-year follow-up and 73% were women. A more concise index with 7 comorbid disease states was identified. The original Charlson index has 16 comorbidities. The stepwise multiple logistic regression integer weights for the 7 comorbidities were 2 for CHF, dementia, neoplasia, and renal disease, and 6 for metastatic solid tumor, liver diseases, and AIDS. Finally, when tested on the second group, the stroke-specific index showed stepwise increases in the cumulative mortality attributable to comorbid diseases (p log rank ÷ 2 < 0.001), whereas the Charlson index did not.
CONCLUSION: This shorter stroke-specific index allows for the development of more highly discriminant comorbidity models for risk adjustment.  相似文献   
145.
1. The recognition of the role of insulin resistance in disease states and the recent development of new drugs that modify insulin-dependent metabolism has led to increased use of the euglycaemic hyperinsulinaemic clamp to measure in vivo insulin sensitivity, but several key aspects of the technique are poorly documented in the literature. 2. We have evaluated the reproducibility and intersubject variation of measurements of insulin sensitivity in groups of insulin-sensitive and insulin-resistant subjects and assessed the effects of hand warming on haemodynamic and metabolic responses. 3. Subjects participated in one of two protocols: (i) 18 healthy male volunteers and 18 patients with hypertension and glucose intolerance were clamped on two occasions, 1 week apart with measurements of insulin sensitivity (M) derived after 120 and 180 min of hyperinsulinaemia; and (ii) six healthy volunteers were clamped on one occasion with simultaneous sampling of antecubital and ‘arterialized’ (dorsal hand) venous blood for comparison of plasma glucose concentrations and oxygen saturation and a further six volunteers were clamped on two occasions with and without the use of hand warming. 4. Measurements of M derived after 120 min (M120) and 180 min (M180) of hyperinsulinaemia were reproducible: the coefficients of repeatability (mg/kg per min) of M120 and M180 were 1.0 and 0.9 for volunteers and 1.0 and 1.0 for the patient group, respectively. The intersubject variation in insulin stimulus was high: coefficients of variation for M180 were 22% for volunteers compared with 38% for the patient group. In volunteers compared with the patient group, hand warming significantly increased venous oxygen saturations (95 ± 2 vs 79 ± 18%, respectively) and glucose concentrations (5.2 ± 0.2 vs 4.5 ± 0.4 mmol/L, respectively) and measurements of M were significantly higher using arterialized compared with antecubital venous blood. However, local hand warming was associated with systemic vasodilatation: blood pressure decreased (e.g. 6mmHg diastolic; P < 0.05) with a compensatory increase in heart rate (8 b.p.m.). 5. In conclusion, clamps of 120 and 180 min duration yielded measurements of M that were reproducible. The technique is much more robust when used in the context of a crossover design because of the significant (20–40%) intersubject variation in M, even among apparently homogeneous male volunteers. Hand warming effectively arterializes venous blood and gives significantly higher M values, but induces systemic vasodilatation, which may confound measurements of M.  相似文献   
146.
147.
Calcium-binding proteins such as calretinin are abundantly expressed in distinctive patterns in the CNS, but their physiological function remains poorly understood. Calretinin is expressed in cerebellar granule cells, which provide the major excitatory input to Purkinje cells through parallel fibers. Calretinin-deficient mice exhibit dramatic alterations in motor coordination and Purkinje cell firing recorded in vivo through unknown mechanisms. In the present study, we used patch-clamp recording techniques in acute slice preparation to investigate the effect of a null mutation of the calretinin gene on the intrinsic electroresponsiveness of cerebellar granule cells at a mature developmental stage. Calretinin-deficient granule cells exhibit faster action potentials and generate repetitive spike discharge showing an enhanced frequency increase with injected currents. These alterations disappear when 0.15 mm of the exogenous fast-calcium buffer BAPTA is infused in the cytosol to restore the calcium-buffering capacity. A proposed mathematical model demonstrates that the observed alterations of granule cell excitability can be explained by a decreased cytosolic calcium-buffering capacity resulting from the absence of calretinin. This result suggests that calcium-binding proteins modulate intrinsic neuronal excitability and may therefore play a role in information processing in the CNS.  相似文献   
148.
This study presents a technique to correct kinking or coiling of the internal carotid artery using patch angioplasty following endarterectomy, resection, and anastomoses of the vessel. Since 1984, 579 carotid endarterectomies have been performed with 19 patients (3.3%) having arteriosclerotic carotid bulb and internal carotid artery disease associated with a carotid kink or coil. These have been treated successfully using the technique of resection and patch angioplasty. The indications for surgery included seven patients with transient ischemic attacks (36.8%); seven patients who had suffered a cerebrovascular accident (36.8%); amaurosis fugax in two patients (10.5%); and one patient each with Hollenhorst plaque (5.3%), central retinal artery occlusion (5.3%), and an asymptomatic critical stenosis (5.3%). All patients had successful repair of the vessel using saphenous vein or Dacron patch angioplasty. There were no perioperative strokes or deaths. Follow-up ranged from four months to 58 months (mean 25 months). All vessels are patent with no evidence of stenosis. One patient had an ipsilateral cerebrovascular accident but had no evidence of recurrent carotid disease. Surgical correction of the carotid kink or coil can present a difficult surgical problem, and resection, fixation, or transposition can be complicated. The technique of endarterectomy, resection of the redundant vessel with anastomosis of the back wail, and patch angioplasty has been used effectively and safely in this series of patients.Presented at the Fifteenth Annual Meeting of the Peripheral Vascular Surgery Society, June 2, 1990, Los Angeles, California.The views and opinions expressed in this paper are those of the authors and do not reflect those of the Department of the Army, Department of Defense, or of the Uniformed Services University of the Health Sciences.  相似文献   
149.
Morrison  MC; Lee  MJ; Stafford  SA; Saini  S; Mueller  PR 《Radiology》1990,176(2):574-576
The authors present two cases of percutaneous cecostomy performed with a modified approach previously described for percutaneous gastrostomy and cholecystostomy. T-fastener devices were used to affix the cecum to the anterior abdominal wall; thus, the potential problem of fecal spillage was prevented. In both cases, adequate fecal drainage was provided without complication.  相似文献   
150.
Elongated Styloid Process (Eagle''s Syndrome) Causing Hemicrania   总被引:1,自引:0,他引:1  
E. Wayne Massey  M.D.  CDR  USNR  MC  Janice Massey  M.D. 《Headache》1979,19(6):339-344
SYNOPSIS
Hemifacial pain and hemicrania can be caused by an elongated styloid process (Eagle's syndrome). This entity is reviewed historically with six case histories and x–rays presented. The etiology of the symptom complex is unclear, but possible mechanisms such as cranial nerve pressure and carotid sympathetic nerve involvement are discussed. Specific treatment is surgical removal of the tip of the styloid process.  相似文献   
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