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21.
M Trevisan R Cooper R Stamler F Gosch A Allen K Liu D Ostrow J Stamler 《Preventive medicine》1983,12(1):133-137
Research evidence on the role of dietary sodium in the etiology and pathogenesis of hypertension is briefly reviewed. This matter is assuming new importance at present, given new data on the efficacy of normalization of blood pressure for adults with so-called "mild" hypertension (average diastolic 90-104 mm Hg), hence the need for safe nutritional-hygienic alternatives to years-long drug treatment for millions of people with such hypertension. Two trials by the authors deal with some unresolved questions in this area. The first, a preliminary study, involved 21 lacto-ovo-vegetarian high school students living in a boarding school. With decrease in daily Na intake from 216 to 72 meq for the experimental compared with the control group, red blood cell Na concentration was significantly lower in the former; systolic pressure was slightly but not significantly lower. The second trial, the Primary Prevention of Hypertension, involves over 200 hypertension-prone persons aged 30-44, and explores the ability in the experimental group to reduce blood pressure and prevent development of hypertension by safe nutritional-hygienic means (weight reduction, dietary Na decrease, avoidance of excess alcohol, rhythmic exercise). Initial results at 6 months are presented. Trials on the prevention and control of hypertension by nonpharmacologic means, including reduced Na intake, and involving analyses of the inter-relationships among dietary Na, other dietary factors, Na metabolism, and blood pressure in samples from different population strata, are an important present-day research need. 相似文献
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Among the 1,892 patients who underwent cerebrovascular digital subtraction angiography at our hospital over the past 18 months, there was a subgroup of 34 patients (65 carotid arteries) for whom noninvasive cerebrovascular test results and standard cerebral arteriograms were also available. These patients were reviewed retrospectively and the ability of both methods to detect hemodynamically significant lesions, defined as a greater than 50 percent reduction in the diameter of the carotid artery, was determined using the arteriograms as the "gold standard." Noninvasive cerebrovascular tests had a sensitivity of 81 percent, a specificity of 95 percent, a positive predictive value of 92 percent, a negative prediction value of 88 percent, and an overall accuracy of 89 percent. Digital subtraction angiography had a sensitivity of 84 percent, a specificity of 92 percent, a positive predictive value of 88 percent, a negative predictive value of 89 percent, and an overall accuracy of 89 percent. If the four cases of hemodynamically significant stenosis of the carotid siphon not detected by digital subtraction angiography had been considered as false-negatives, its sensitivity would have been reduced to 72 percent. In patients with hemispheric cerebral ischemia, we found noninvasive cerebrovascular tests neither necessary nor cost-effective. Digital subtraction angiography, on the other hand, often provided definitive diagnostic information in such patients if the intracranial circulation was well defined and the extracranial lesion corresponded to the patients' symptoms. Noninvasive cerebrovascular testing was the safest and most cost-effective technique for screening patients with asymptomatic bruits, atypical, nonhemispheric cerebral symptoms, and those who have undergone carotid endarterectomy. If the noninvasive cerebrovascular test result was positive or equivocal, digital subtraction angiography was performed to localize the responsible lesion and exclude carotid occlusion. 相似文献
23.
Adenoid cystic carcinoma: factors influencing survival. 总被引:10,自引:0,他引:10
We have reviewed our experience with 264 patients treated for adenoid cystic carcinoma of salivary origin. This study updates a previous report from our hospital and includes all patients treated during a 30 year period who were eligible for a minimum follow-up of 10 years. The tumor arose in minor salivary (mucous) glands in two thirds of the patients; half had received treatment elsewhere, and both sexes were equally represented. Actuarial survival curves and "cure" rates calculated by the direct method confirm that clinical staging provides a reliable prognostic guide. We are unable to demonstrate that the microscopic appearance of the tumor exerts a predictable effect on treatment results. Although some patients lived for many years after resection despite local recurrence and distant metastases, prolonged survival was unusual in patients with stage 3 lesions, particularly in those with sinus or submaxillary gland primaries. Based on the site of origin of the tumor and its clinical stage, it is now possible to select which patients with adenoid cystic carcinoma have the most ominous prognosis and perhaps plan a more appropriate operation. More importantly, these data may help focus on the subpopulation at greatest risk, which is vital to the design of any prospective study to assess the value of adjunctive irradiation and chemotherapy. 相似文献
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《Journal of Clinical Orthopaedics and Trauma》2021,12(6):1110-1116
BackgroundOpen pelvic fractures are rare injuries, associated with high patient morbidity and mortality. Few studies have investigated the impact of patient demographics, comorbidities, and injury related factors on complication and mortality rates. The purpose of this study was to: (1) identify the overall incidence of complications and mortality after open pelvic fractures, (2) compare patient factors between those who did and did not develop complications, (3) identify perioperative independent risk factors for complications and mortality.MethodsA query was performed for patients with open pelvic fractures between 2007 and 2017 using the American College of Surgeons National Trauma Data Bank. Patient and injury specific variables were collected and complications were identified using International Classification of Disease Ninth and Tenth edition Codes. Patient demographic and perioperative data was compared using Fisher’s exact test and chi-square test for categorical variables, and Welch’s t-test for continuous variables. Using pooled data from multiple imputations, logistic regressions were used to calculate odds ratios and confidence intervals of independent risk factors for complications.ResultsA total of 19,834 open pelvic fracture cases were identified, with 9622 patients (48.5%) developing at least one complication. Patients who developed complications were older (35.0 vs 38.1 years), and had higher Injury Severity Scores (17.7 vs 26.5), lower Glasgow Coma Scores (14.2 vs 11.7), and a larger proportion presenting with hypotension (21% vs 6.9%). After pooled regression involving 19 factors, these were the strongest independent predictors of inpatient complication and mortality.ConclusionWe report a mortality rate of 14%, with an inclusive complication rate of 48.5%. Evaluating risk factors for morbidity and mortality for this devastating orthopaedic injury provides knowledge of an inherently sparse population.Level of EvidenceLevel II, Retrospective study. 相似文献
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Liane A. Arcinas Weiang Yan Davinder S. Jassal Michael P. Love Michael H. Yamashita Basem Elbarouni 《The Canadian journal of cardiology》2018,34(12):1688.e5-1688.e7
We describe a case of a 54-year-old woman who had a right cardiac mass found on coronary angiography. Echocardiography, computed tomography, and cardiac magnetic resonance imaging characterized it as a thrombosed giant right coronary artery aneurysm. This was confirmed on pathology. We present the role of multimodality cardiovascular imaging in the diagnosis and characterization of a giant coronary artery aneurysm. 相似文献