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81.
We report three cases of dry beriberi in adolescents who underwent gastric bypass surgery for clinically severe obesity. The key to successful treatment of this problem lies in prompt recognition and thiamine supplementation.  相似文献   
82.
Geometric leaf placement strategies for multileaf collimators (MLCs) typically involve the expansion of the beam's-eye-view contour of a target by a uniform MLC margin, followed by movement of the leaves until some point on each leaf end touches the expanded contour. Film-based dose-distribution measurements have been made to determine appropriate MLC margins--characterized through an index d90--for multileaves set using one particular strategy to straight lines lying at various angles to the direction of leaf travel. Simple trigonometric relationships exist between different geometric leaf placement strategies and are used to generalize the results of the film work into d90 values for several different strategies. Measured d90 values vary both with angle and leaf placement strategy. A model has been derived that explains and describes quite well the observed variations of d90 with angle. The d90 angular variations of the strategies studied differ substantially, and geometric and dosimetric reasoning suggests that the best strategy is the one with the least angular variation. Using this criterion, the best straightforwardly implementable strategy studied is a 'touch circle' approach for which semicircles are imagined to be inscribed within leaf ends, the leaves being moved until the semicircles just touch the expanded target outline.  相似文献   
83.
BACKGROUND: Dysmenorrhea is highly prevalent and causes much work loss and discomfort. A treatment with a new mechanism of action could benefit women of menstruating age. A study was undertaken to assess the efficacy of guaifenesin as a treatment for primary dysmenorrhea because of its effects of cervical dilation and cervical mucous thinning. METHODS: Thirty-four subjects with primary dysmenorrhea were enrolled in a double-blind, placebo-controlled study. Three treatment surveys measured 10 symptoms (lower abdominal pain, general abdominal pain, back pain, headache, nausea, diarrhea, constipation, menstrual flow, weakness, and activities of daily living) on a 100-mm visual analog scale. Nonstudy analgesic use was also measured. RESULTS: Twenty-five subjects returned the first treatment survey, and 17 returned all 3 surveys. Results were nonsignificant, but guaifenesin trended toward being better than placebo for dysmenorrhea pain and associated constitutional symptoms and caused no worsening of symptoms. Lower abdominal mean pain scores from the first survey decreased 38 mm for guaifenesin versus 7 mm for placebo. By the third survey, only 2 of 8 guaifenesin participants took nonstudy analgesics compared with all 9 placebo subjects. CONCLUSIONS: Guaifenesin may be useful in the treatment of primary dysmenorrhea. A larger study is needed to validate these initial findings.  相似文献   
84.
85.
OBJECTIVE: To identify the demographic, clinical, and echocardiographic features that predict the use of inotropic support at separation from cardiopulmonary bypass (CPB). Design: Retrospective study of consecutive patients undergoing coronary artery bypass graft (CABG) surgery. SETTING: Referral center for cardiothoracic surgery at a university hospital. PARTICIPANTS: One thousand nine patients undergoing either CABG or combined CABG and valve surgery with CPB in whom an intraoperative transesophageal echocardiography (TEE) examination was performed. INTERVENTIONS: Inotropic support was defined as the use of dopamine >/=5 microg/kg/min; any dose of epinephrine, norepinephrine, dobutamine, and milrinone; or the insertion of an IABP during separation from CPB. Support was implemented by the anesthesia care team as clinically indicated. Comprehensive TEE examinations were conducted before CPB in all patients according to published guidelines and subsequently reviewed by a single, independent operator. MEASUREMENTS and MAIN RESULTS: Inotropic support was used in a total of 394 patients (39%) at separation from CPB. The study identified 6 significant, independent predictors of inotrope use: (1) Wall Motion Score Index, (2) combined CABG and mitral valve repair or replacement surgery, (3) left ventricular ejection fraction <35%, (4) reoperation, (5) moderate-to-severe mitral regurgitation, and (6) aortic cross-clamp time. CONCLUSIONS: Incorporating data from a comprehensive intraoperative TEE examination, the authors identified 6 reproducible factors that independently predict the use of inotropic support at separation from CPB.  相似文献   
86.
STUDY OBJECTIVE: Determine prevalence of osteoporosis screening and prevention and modes of treatment in women older than 65 years at risk of osteoporosis. METHODS: Retrospective chart review of older female patients seeking osteoporosis screening in the community setting. RESULTS: 399 women at risk of low bone mineral density (BMD) underwent dual-energy x-ray absorptiometry scanning. Among participants younger than 65 years (n=52), low BMD was diagnosed in 44.2%; among participants older than 65 years (n=347), low BMD was diagnosed in 70.0%, a statistically significant difference (P=.001). CONCLUSION: From a community-level perspective, the authors have shown that osteoporosis screening at local senior centers, living facilities, and health fairs is an effective tool for identifying low BMD in women at high risk of osteopenia and osteoporosis.  相似文献   
87.
BACKGROUND: Perioperative delirium is common in high-risk surgery and is associated with age, education, preoperative cognitive functioning, pre-existing medical conditions, and postoperative complications. We investigated these factors as well as lifestyle and demographic variables by using cognitive measures that were more sensitive than those used in previous studies. METHODS: Extensive medical and demographic data were collected on 102 patients between 41 and 88 years of age to identify comorbidities and lifestyle considerations preoperatively. Elective abdominal aortic aneurysm surgery was performed under combined general/epidural anesthesia with postoperative epidural analgesia. A battery of sensitive, cognitive measures was administered preoperatively, at the time of discharge from hospital, and 3 months postoperatively. Symptoms of delirium were assessed during the first 6 postoperative days using Diagnostic and Statistical Manual of Mental Disorders-4th Edition criteria. Intraoperative and postoperative data, including medications, vital signs, conduct of the surgery and anesthesia, complications, and details of pain control, were collected. RESULTS: Delirium occurred in 33% of the patients during the first 6 days after surgery. Longer duration of delirium was related to lower education, preoperative depression, and greater preoperative psychoactive medication use. Characteristics of the surgery and hospital stay were unrelated to the development of delirium. Patients who were diagnosed with delirium had lower cognitive scores during each of the three assessment periods, even when controlling for age and education. Logistic regression analysis indicated that the most powerful preoperative predictors of delirium were number of pack years smoked (P = .001), mental status scores (P = .003), and number of psychoactive medications (P = .005). CONCLUSION: A significant proportion of patients undergoing elective abdominal aortic aneurysm repair are susceptible to the development of delirium and are at risk for cognitive dysfunction after surgery. Our findings have implications for promoting long-term lifestyle changes, including smoking cessation and improved management of mental health as risk-reduction strategies.  相似文献   
88.
An 8-year-old boy presented with fulminant necrotizing infection resembling gas gangrene following penetrating trauma from a tree branch. Bacillus cereus was isolated from tissue specimens, showing that unexpected pathogens can be isolated. It is essential to submit specimens for culture, as this organism is typically resistant to beta-lactam antibiotics and metronidazole, the empiric choice for gas gangrene.  相似文献   
89.
Murder of a loved one typically has a tremendous impact on the family as a whole and on individual members. While it is true people often react in very similar ways following such a traumatic loss, they do not necessarily grieve in the same way or at the same time. Additionally, the murder may have a detrimental effect on the stability, developmental tasks, communication patterns, and role functioning of the family. This paper explores some of the many issues and challenges families must face in the aftermath of a murder.  相似文献   
90.
There is an urgent need to change the presentations and delivery technologies of current vaccines. Until recently, these factors had not been key criteria in the selection of vaccines for program use. Recent and current changes in the field of vaccines and their delivery lead the authors to postulate that a major paradigm shift will take place over the next decade to revolutionize vaccine presentation and delivery in national immunization programs. The programmatic needs for certain vaccine presentations will increasingly dictate elements of vaccine development and manufacture. Over the next decade, an inexorable drift towards firstly, single-dose preparations, and secondly, delivery technologies other than the conventional needle and syringes is anticipated. A unified system capable of delivering multiple antigens as a single dose is urgently needed; however, changing the status quo of vaccine manufacture is not easy. The market predominantly produces vaccines delivered by needle and syringe. Profits for manufacturers from sales to developing countries are marginal at best, and there is little financial incentive to change. Global leaders will need to take bold decisions and begin demanding vaccines which have a presentation that lends them to safer, more practical delivery systems. If a strong enough case can be made to restructure the vaccine manufacturing industry, either through market forces, global bodies, such as the World Health Organization and the United Nations Children's Fund, or both, a dramatic change could be brought about that will make vaccine delivery simpler and safer. A globally coordinated approach to funding research and the introduction of a multiple-antigen, single-dose delivery system is urgently needed. The needs are clear, and this review argues that if the case is presented strongly enough, the resources will be found.  相似文献   
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