全文获取类型
收费全文 | 4803篇 |
免费 | 400篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 137篇 |
妇产科学 | 109篇 |
基础医学 | 704篇 |
口腔科学 | 90篇 |
临床医学 | 433篇 |
内科学 | 861篇 |
皮肤病学 | 38篇 |
神经病学 | 445篇 |
特种医学 | 219篇 |
外科学 | 950篇 |
综合类 | 102篇 |
一般理论 | 2篇 |
预防医学 | 410篇 |
眼科学 | 45篇 |
药学 | 258篇 |
中国医学 | 5篇 |
肿瘤学 | 360篇 |
出版年
2023年 | 24篇 |
2022年 | 52篇 |
2021年 | 101篇 |
2020年 | 60篇 |
2019年 | 105篇 |
2018年 | 119篇 |
2017年 | 82篇 |
2016年 | 100篇 |
2015年 | 100篇 |
2014年 | 143篇 |
2013年 | 224篇 |
2012年 | 317篇 |
2011年 | 314篇 |
2010年 | 160篇 |
2009年 | 155篇 |
2008年 | 251篇 |
2007年 | 261篇 |
2006年 | 200篇 |
2005年 | 200篇 |
2004年 | 188篇 |
2003年 | 148篇 |
2002年 | 163篇 |
2001年 | 136篇 |
2000年 | 135篇 |
1999年 | 121篇 |
1998年 | 43篇 |
1997年 | 45篇 |
1996年 | 35篇 |
1995年 | 51篇 |
1994年 | 38篇 |
1993年 | 24篇 |
1992年 | 96篇 |
1991年 | 82篇 |
1990年 | 111篇 |
1989年 | 92篇 |
1988年 | 73篇 |
1987年 | 73篇 |
1986年 | 78篇 |
1985年 | 60篇 |
1984年 | 51篇 |
1983年 | 39篇 |
1982年 | 25篇 |
1981年 | 26篇 |
1979年 | 40篇 |
1978年 | 27篇 |
1977年 | 20篇 |
1976年 | 20篇 |
1974年 | 30篇 |
1972年 | 19篇 |
1971年 | 18篇 |
排序方式: 共有5214条查询结果,搜索用时 0 毫秒
71.
Talan DA Stamm WE Hooton TM Moran GJ Burke T Iravani A Reuning-Scherer J Church DA 《JAMA》2000,283(12):1583-1590
Context The optimal antimicrobial regimen and treatment duration for acute uncomplicated pyelonephritis are unknown. Objective To compare the efficacy and safety of a 7-day ciprofloxacin regimen and a 14-day trimethoprim-sulfamethoxazole regimen for the treatment of acute pyelonephritis in women. Design Randomized, double-blind comparative trial conducted from October 1994 through January 1997. Setting Twenty-five outpatient centers in the United States. Patients Of 378 enrolled premenopausal women aged at least 18 years with clinical diagnosis of acute uncomplicated pyelonephritis, 255 were included in the analysis. Other individuals were excluded for no baseline causative organism, inadequate receipt of study drug, loss to follow-up, no appropriate cultures, and other reasons. Interventions Patients were randomized to oral ciprofloxacin, 500 mg twice per day for 7 days (with or without an initial 400-mg intravenous dose) followed by placebo for 7 days (n = 128 included in analysis) vs trimethoprim-sulfamethoxazole, 160/800 mg twice per day for 14 days (with or without intravenous ceftriaxone, 1 g) (n = 127 included in the analysis). Main Outcome Measure Continued bacteriologic and clinical cure, such that alternative antimicrobial drugs were not required, among evaluable patients through the 4- to 11-day posttherapy visit, compared by treatment group. Results At 4 to 11 days posttherapy, bacteriologic cure rates were 99% (112 of 113) for the ciprofloxacin regimen and 89% (90 of 101) for the trimethoprim-sulfamethoxazole regimen (95% confidence interval [CI] for difference, 0.04-0.16; P = .004). Clinical cure rates were 96% (109 of 113) for the ciprofloxacin regimen and 83% (92 of 111) for the trimethoprim-sulfamethoxazole regimen (95% CI, 0.06-0.22; P = .002). Escherichia coli, which caused more than 90% of infections, was more frequently resistant to trimethoprim-sulfamethoxazole (18%) than to ciprofloxacin (0%; P<.001). Among trimethoprim-sulfamethoxazoletreated patients, drug resistance was associated with greater bacteriologic and clinical failure rates (P<.001 for both). Drug-related adverse events occurred in 24% of 191 ciprofloxacin-treated patients and in 33% of 187 trimethoprim-sulfamethoxazoletreated patients, respectively (95% CI, -0.001 to 0.2). Conclusions In our study of outpatient treatment of acute uncomplicated pyelonephritis in women, a 7-day ciprofloxacin regimen was associated with greater bacteriologic and clinical cure rates than a 14-day trimethoprim-sulfamethoxazole regimen, especially in patients infected with trimethoprim-sulfamethoxazoleresistant strains. 相似文献
72.
BACKGROUND: There is evidence that the stage of illness at which antipsychotic treatment is initiated in schizophrenia may have consequences for its subsequent course. How this might relate to impaired adaptive life functioning in the long-term is poorly understood. METHODS: Thirty-eight inpatients, many of whom had been admitted in the preneuroleptic era, were assessed using the Social-Adaptive Functioning Evaluation (SAFE); constituent clinical and medication phases of the lifetime trajectory of their illnesses were then analyzed to identify predictors of SAFE score using multiple regression modeling. RESULTS: The primary, independent predictor of SAFE score was duration of initially unmedicated psychosis, which accounted for 22% of variance (p<.001) therein. Conversely, duration of subsequently treated illness, although decades longer, failed to predict SAFE score. CONCLUSIONS: These findings are consistent with some form of "progressive" process, particularly over the first several years following the emergence of psychosis, which is associated with accrual of deficits in adaptive life functioning. 相似文献
73.
John L. Moran MBBS FRACP Patricia J. Solomon PhD David E. Warn PhD 《Health services & outcomes research methodology》2004,5(3-4):207-226
Methodological aspects of meta-analytic practice, heterogeneity, publication bias, metaregression and effect metric, were investigated in 14 meta-analyses reflecting major therapeutic concern in Critical Care practice. Compared with the standard Q test, the exact Zelen test was more sensitive in identifying heterogeneity. Assessment of heterogeneity impact by the I 2 statistic was consistent with inferences afforded by both the Q and Zelen test. Publication bias was subject to test and metric determination: funnel plots exhibited variable asymmetry across studies and between metrics; the regression asymmetry test appeared more sensitive than the rank correlation test; the “trim and fill” method was the most sensitive, but suggested, on the basis of quantification of the effects of potentially missing studies, that meta-analyses may be resistant to such missingness. Metaregression of treatment effect against control risk using Bayesian hierarchical regression in all metrics (log odds ratio, log risk ratio and RD) suggested that naïve linear regression approaches over-diagnosed significant relationships and exhibited regression dilution. Heterogeneity, publication bias and risk related treatment effects all demonstrate estimator and metric dependence; the RD metric would appear the most capricious in this regard. 相似文献
74.
Stamm C Friehs I Moran AM Zurakowski D Bacha E Mayer JE Jonas RA Del Nido PJ 《The Journal of thoracic and cardiovascular surgery》2000,120(4):755-763
OBJECTIVE: A number of patients with Williams syndrome or other forms of elastin arteriopathy have stenoses of pulmonary arteries in addition to supravalvular aortic stenosis. We sought to investigate the effect of the degree of pulmonary arterial stenosis on the prognosis after an operation for supravalvular aortic stenosis to help define the optimal treatment strategy for patients with severe forms of elastin arteriopathy. METHODS: Between 1960 and 1999, 33 patients underwent operations for supravalvular aortic stenosis while having significant stenoses of the pulmonary arteries. We retrospectively reviewed patient charts, obtained current follow-up information, and determined risk factors for survival and reoperation. RESULTS: Fifteen patients with moderate right-sided obstructions (confirmed by pulmonary artery Z-scores and right ventricular/descending aortic pressure ratio) underwent operations for supravalvular aortic stenosis only. Eighteen patients had more severe right-sided obstructions and underwent surgical relief of pulmonary arterial stenoses or right ventricular outflow tract obstruction in addition to operations for supravalvular aortic stenosis. Eight patients had undergone preoperative balloon dilations of stenotic pulmonary arteries. There were 6 early deaths and 1 late death in our series. Survival at 10 and 20 years was 76% (70% confidence interval, 68%-84%) and freedom from reintervention was 59% (70% confidence interval, 46%-71%) at 10 years and 49% (70% confidence interval, 35%-62%) at 20 years. Multivariate analysis revealed that patients with a right ventricular/descending aortic pressure ratio of 1.0 or more were at higher risk for reintervention but not for death. CONCLUSIONS: Surgical treatment of pulmonary artery obstructions in elastin arteriopathy is palliative but, in conjunction with balloon dilation of peripheral pulmonary arteries, offers good long-term survival to patients with the severest form of elastin arteriopathy. 相似文献
75.
76.
18F]fluorodeoxyglucose uptake by positron emission tomography predicts outcome of non-small-cell lung cancer. 总被引:9,自引:0,他引:9
Ryohei Sasaki Ritsuko Komaki Homer Macapinlac Jeremy Erasmus Pamela Allen Kenneth Forster Joe B Putnam Roy S Herbst Cesar A Moran Donald A Podoloff Jack A Roth James D Cox 《Journal of clinical oncology》2005,23(6):1136-1143
PURPOSE: To determine whether the standardized uptake value (SUV) of [(18)F]fluorodeoxyglucose uptake by positron emission tomography could be a prognostic factor for non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: One hundred sixty-two patients with stage I to IIIb NSCLC were analyzed. Overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and local-regional control (LRC) were calculated by the Kaplan-Meier method and evaluated with the log-rank test. The prognostic significance was assessed by univariate and multivariate analyses. RESULTS: There were 93 patients treated with surgery and 69 patients treated with radiotherapy. A cutoff of 5 for the SUV for the primary tumor showed the best discriminative value. The SUV for the primary tumor was a significant predictor of OS (P = .02) in both groups. Low SUVs (= 5.0) showed significantly better DFS rates than those with high SUVs (> 5.0; surgery group, P = .02; radiotherapy group, P = .0005). Low SUVs (= 5.0) indicated a significantly better DFS than those with high SUVs (> 5.0; stage I or II, P = .02; stage IIIa or IIIb, P = .004). However, using the same cutoff point of 5, the SUV for regional lymph nodes was not a significant indicator for DFS (P = .19), LRC (P = .97), or DMFS (P = .17). The multivariate analysis showed that the SUV for the primary tumor was a significant prognostic factor for OS (P = .03) and DFS (P = .001). CONCLUSION: The SUV of the primary tumor was the strongest prognostic factor among the patients treated by curative surgery or radiotherapy. 相似文献
77.
SB Grover N Midha M Gupta U Sharma VH Talib 《Journal of Medical Imaging and Radiation Oncology》2005,49(2):175-178
The clinical manifestations of chronic disseminated histoplasmosis are non-specific and resemble those of other chronic infections and malignancies. We report the radiographic, sonographic and contrast-enhanced CT appearances of histoplasmosis in an adult male with non-insulin dependent diabetes mellitus, who was HIV negative and presented with weight loss and pyrexia. Imaging studies simulated tuberculosis with mediastinal lymphadenopathy, bilateral fibrotic lung lesions, hepatomegaly and bilateral hypoattenuating adrenal enlargement, without clinical or laboratory evidence of hypoadrenalism. Computed tomography-guided fine-needle aspiration biopsy of adrenal glands revealed Histoplasma capsulatum. We report our experience to increase awareness of the imaging spectrum of disseminated histoplasmosis and its similarity to tuberculosis as, with increasing incidence of AIDS, the chances of these infections are likely to increase. Moreover, awareness of this entity is important because it is known that untreated disseminated histoplasmosis is fatal. 相似文献
78.
A realist qualitative study to explore how low‐income pregnant women use Healthy Start food vouchers
Heather Ohly Nicola Crossland Fiona Dykes Nicola Lowe Victoria Hall Moran 《Maternal & child nutrition》2019,15(1)
Healthy Start is the UK government's food voucher programme for low‐income pregnant women and young children. It was introduced in 2006, but the impact of the programme on nutritional outcomes remains understudied. This study sought to explore potential outcomes of the Healthy Start programme (including intended and unintended outcomes) and develop explanations for how and why these outcomes might occur. A realist review preceded this study, in which programme theories were developed and tested using existing evidence. This qualitative study aimed to further refine and consolidate the programme theories from the realist review while remaining open to new and emerging theories (or hypotheses) about how low‐income pregnant women use Healthy Start vouchers. Semistructured interviews were conducted with 11 low‐income women from North West England, who received Healthy Start vouchers during pregnancy. A realist logic of analysis was applied to generate clear and transparent linkages between outcomes and explanations. The findings suggested that some women used the vouchers to improve their diets during pregnancy (intended outcome), whereas some women were diverted towards alternative or unintended outcomes. Women's circumstances, values, beliefs, and motivations influenced how they perceived and responded to the vouchers. This paper presents four evidence‐based programme theories to explain four contrasting (and potentially overlapping) outcomes: dietary improvements (theory refined from review), shared benefits (new theory), financial assistance (theory refined from review), and stockpiling formula (new theory). It considers how the Healthy Start programme could be improved, to increase the possibilities for low‐income women to experience the intended outcome of dietary improvements. 相似文献
79.
Guido Marcucci Wendy Stock Guowei Dai Rebecca B Klisovic Shujun Liu Marko I Klisovic William Blum Cheryl Kefauver Dorie A Sher Margaret Green Mollie Moran Kati Maharry Steven Novick Clara D Bloomfield James A Zwiebel Richard A Larson Michael R Grever Kenneth K Chan John C Byrd 《Journal of clinical oncology》2005,23(15):3404-3411
80.
Hassane Zouhal Benjamin Barthlmy Alexandre Dellal Sghaeir Zouita Abderraouf Ben Abderrahman Omar Ben Ounis Claire Tourny Ali Belamjahad Said Ahmaidi Thierry Paillard Nicolas Dyon Benoit Bideau Ayoub Saeidi Jason Moran Anis Chaouachi George P. Nassis Christopher Carling Urs Granacher Guillaume Rav 《Journal of Sports Science and Medicine》2022,21(3):482