首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1976篇
  免费   107篇
  国内免费   2篇
耳鼻咽喉   44篇
儿科学   118篇
妇产科学   304篇
基础医学   226篇
口腔科学   31篇
临床医学   171篇
内科学   397篇
皮肤病学   23篇
神经病学   156篇
特种医学   50篇
外科学   215篇
综合类   8篇
一般理论   3篇
预防医学   111篇
眼科学   55篇
药学   91篇
肿瘤学   82篇
  2024年   4篇
  2023年   15篇
  2022年   21篇
  2021年   52篇
  2020年   41篇
  2019年   66篇
  2018年   63篇
  2017年   49篇
  2016年   68篇
  2015年   62篇
  2014年   92篇
  2013年   110篇
  2012年   165篇
  2011年   155篇
  2010年   90篇
  2009年   68篇
  2008年   132篇
  2007年   125篇
  2006年   147篇
  2005年   111篇
  2004年   118篇
  2003年   73篇
  2002年   83篇
  2001年   13篇
  2000年   12篇
  1999年   12篇
  1998年   12篇
  1997年   9篇
  1996年   11篇
  1995年   4篇
  1994年   6篇
  1993年   7篇
  1992年   3篇
  1991年   6篇
  1990年   5篇
  1989年   4篇
  1988年   10篇
  1987年   5篇
  1986年   4篇
  1985年   10篇
  1984年   8篇
  1983年   4篇
  1982年   2篇
  1981年   6篇
  1976年   3篇
  1975年   3篇
  1974年   3篇
  1972年   3篇
  1970年   2篇
  1967年   3篇
排序方式: 共有2085条查询结果,搜索用时 15 毫秒
1.
ObjectiveTo evaluate the significance of sonographic perinephric fluid collection on the emergent management of patients with acute urinary stone obstruction.MethodsWe conducted a prospective study with retrospective analysis. Since January 2016 through July 2017, patients admitted to our tertiary hospital's emergency department (ED) with suspected symptomatic urinary stones underwent ultrasound evaluation. Images were prospectively interpreted by experienced radiologist who analyzed each case for the following imaging features: hydronephrosis, perinephric fluid and urethral stone identification. The presence and measurements of perinephric fluid were re-evaluated by second radiologist who was blinded for the first reader's measurements. Retrospective analysis was conducted to evaluate for an association between perinephric fluid collection and the following outcome variables: need for analgesics, the number of doses of analgesics and the amount of morphine (mg) in the ED, elevation of creatinine levels, hospitalization and need for urological interventions.ResultsThe need for analgesics, the number of doses of analgesics and the amount of morphine were significantly associated with the presence of perinephric fluid (p < 0.05). The odds ratio for the need for analgesics was 3.8 in the presence of any perinephric fluid, and 8.9 in the presence of moderate/severe perinephric fluid. No other patient outcome variables were found to be significantly associated with the presence of perinephric fluid (p > 0.05).ConclusionsThis study shows a correlation between sonographic evidence of perinephric fluid and more severe pain. Therefore, an emergency physician can consider the evidence of perinephric fluid, in acute urethral stone obstruction, a predictor for more severe pain.  相似文献   
2.
Reply     
  相似文献   
3.
4.
OBJECTIVE: To evaluate the influence of gravidity on the results of in vitro fertilization (IVF)-embryo transfer (ET) cycles. PATIENTS AND METHODS: All consecutive women aged <35 years admitted to our IVF unit from January 2002 to December 2004 were enrolled in the study. Only patients undergoing one of their first three IVF cycle attempts were included. Gravidity, ovarian stimulation characteristics, number of oocytes retrieved, number of embryo transferred and clinical pregnancy rate were assessed. RESULTS: Three hundred and forty-two consecutive IVF cycles were evaluated. One hundred and sixty-one cycles were from nulligravidas and 181 from women with a history of at least one previous clinical pregnancy. Forty-eight (29.8%) clinical pregnancies were observed in the nulligravida group and 56 (30.9%) in the gravida group. There were no differences between nulligravidas and gravidas in causes of infertility, length of ovarian stimulation, peak estradiol and progesterone levels, number of oocytes retrieved, fertilization rate and number of embryos transferred. Gravidas were significantly older (30.4 vs. 27.6 years, p < 0.001) and used more gonadotropin ampoules (36.1 vs. 31.8, p < 0.004) compared with the nulligravidas. CONCLUSIONS: Patient gravidity has no influence on the likelihood of achieving pregnancy in IVF-ET cycles.  相似文献   
5.
OBJECTIVE: Previous studies have identified age, renal failure and aneurysm extent as predictors of mortality following thoracoabdominal and descending thoracic aortic aneurysm (TAA) repair. We studied the impact of coronary artery disease (CAD) and cardiac function on 30-day mortality following TAA repair. METHODS: Between February 1991 and May 2001, we performed 854 TAA repairs. Two hundred ninety-one patients (34%) had a history of coronary artery disease. One hundred forty-one/291 (49%) had undergone coronary artery bypass surgery (CAB) prior to TAA repair. We conducted multivariable analyses of known risk factors along with the left ventricular ejection fraction (EF) and prior CAB to determine the adjusted effect of CAD on outcome. RESULTS: Mortality in patients with CAD was 54/291 (18%) compared to 75/563 (13%) without CAD (P<0.05). In patients who had prior CAB, mortality was 31/141 (22%) compared to 98/713 (14%) patients without prior CAB, (P<0.02). In multivariable analysis, the effects of CAD and CAB on mortality were eliminated by consideration of a low EF (defined as less than 50%). CONCLUSION: Impaired left ventricular function appears to be the strongest cardiac predictor of mortality for TAA repair, independent of the presence of coronary artery disease or coronary artery bypass revascularization.  相似文献   
6.
Spontaneous ovarian hyperstimulation mimicking an ovarian tumour   总被引:1,自引:1,他引:0  
Ovarian hyperstimulation syndrome in a spontaneous singletonpregnancy is exceedingly rare. We report a case of ovarian hyperstimulationpresenting as bilateral ovarian masses in association with spontaneouspregnancy, occurring in a woman with disturbed liver function.A possible mechanism is discussed.  相似文献   
7.
This study investigated whether immunostimulatory DNA sequences (ISS) induce a transient or sustained inhibition of Th2 responses to inhaled antigen. We sensitized mice with subcutaneous injections to develop a Th2 response to ovalbumin (ova) and then administered a dose of ISS prior to ova inhalation challenge. Mice were then rechallenged with ova by inhalation a second time at varying time points after the first ova inhalation (1 to 8 weeks later) to determine whether the ISS dose administered prior to the first ova inhalation protected against a subsequent second ova inhalation challenge. A single dose of ISS inhibited the Th2 response to the first inhalation of ova antigen, as well as 4 weeks later to the second inhalation of ova. However, ISS did not inhibit a Th2 response to the second inhalation of ova 8 weeks later. The reversible inhibition of Th2 responses at 8 weeks suggests the need for repeated ISS administration at monthly intervals.  相似文献   
8.
Remote interventions are increasingly used in transplant medicine but have rarely been rigorously evaluated. We investigated a remote intervention targeting immunosuppressant management in pediatric lung transplant recipients. Patients were recruited from a larger multisite trial if they had a Medication Level Variability Index (MLVI) ≥2.0, indicating worrisome tacrolimus level fluctuation. The manualized intervention included three weekly phone calls and regular follow-up calls. A comparison group included patients who met enrollment criteria after the subprotocol ended. Outcomes were defined before the intent-to-treat analysis. Feasibility was defined as ≥50% of participants completing the weekly calls. MLVI was compared pre- and 180 days postenrollment and between intervention and comparison groups. Of 18 eligible patients, 15 enrolled. Seven additional patients served as the comparison. Seventy-five percent of participants completed ≥3 weekly calls; average time on protocol was 257.7 days. Average intervention group MLVI was significantly lower (indicating improved blood level stability) at 180 days postenrollment (2.9 ± 1.29) compared with pre-enrollment (4.6 ± 2.10), = .02. At 180 days, MLVI decreased by 1.6 points in the intervention group but increased by 0.6 in the comparison group (= .054). Participants successfully engaged in a long-term remote intervention, and their medication blood levels stabilized. NCT02266888.  相似文献   
9.
Identification and histologic study of the sentinel node (SN) is an acceptable, yet not firmly established, guide for treating intermediate-thickness melanoma. This study widens the range of applications of this technique. We included 97 patients with intermediate-thickness melanoma lesions or lesions for which there is no standard treatment. Fifty-six underwent preoperative lymphoscintigraphy, and all underwent intraoperative lymphatic mapping (IOLM) using blue dye, followed by frozen section study and total node processing by serial sections. Elective lymph node dissection was performed in cases of metastasis to the sentinel node or technical failures with high risk. Four categories were defined: (A) intermediate-thickness lesions (mean 2.27 mm) (n= 45); (B) thin lesions (mean 1.14 mm) with risk factors of regional failure (n= 27); (C) lesion thickness close to but more than 4 mm (n= 10); and (D) lesions of undetermined thickness (n= 15). Median follow-up was 30 months (range 13–51 months). Intraoperative lymphatic mapping successfully identified the sentinel node (SN) in 93% of basins explored. Metastases were detected in 11 SNs. There were three lymph basin recurrences in patients with previously negative SNs, all salvaged by therapeutic lymph basin dissection and are NED (no evidence of disease). Two SN+ patients had systemic recurrences; one died of his disease, and the other is alive with disease. One SN patient died NED owing to other cause. This technique spared 83% of category A patients from lymph node dissection. It allowed better staging and better decision making for treatment in categories B and D; and it prevented early regional recurrences in category C patients. Intraoperative lymphatic mapping with SN guidance is a novel, low-morbidity approach applicable and advantageous for a wide range and subgroups of melanoma patients.  相似文献   
10.
Susac syndrome.     
OBJECTIVE: The objective of this study was to describe the clinical manifestations; radiographic, audiometric, and retinal fluorescein angiography findings; pathogenesis and treatment of Susac syndrome with review of the literature. STUDY DESIGN: We conducted a retrospective case review. SETTING: This study was conducted at a tertiary referral center. PATIENT: A 50-year-old woman presented with recurrent episodes of neurologic symptoms, bilateral sensorineural hearing loss, and silent retinal artery occlusion. INTERVENTIONS: The patient underwent complete evaluation, including magnetic resonance image studies, audiometric tests, and retinal fluorescein angiography. She was treated initially with corticosteroids and later with other immunosuppressive agents. RESULTS: The patient was initially diagnosed with left sudden sensorineural hearing loss. Despite comprehensive clinical and laboratory studies that did not reveal systemic disease, 3 weeks later, the patient developed vertigo, sensorineural hearing loss, and tinnitus in the opposite ear. The neurologic involvement and the bilateral audiologic manifestations raised the possibility of Susac syndrome. CONCLUSION: Susac syndrome is a rare disorder of unknown origin characterized by the triad of encephalopathy, fluctuating hearing loss, and visual loss resulting from microangiopathy of the brain, cochlea, and retina. The multiple organ involvement seen in Susac syndrome raises a differential diagnosis ranging from autoimmune disease, through systemic vasculitis, to multiple sclerosis. Otolaryngologists should be aware of this syndrome as a result of the vestibulocochlear manifestations and the multidisciplinary evaluation that is required.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号