全文获取类型
收费全文 | 4593篇 |
免费 | 392篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 209篇 |
妇产科学 | 69篇 |
基础医学 | 453篇 |
口腔科学 | 60篇 |
临床医学 | 517篇 |
内科学 | 948篇 |
皮肤病学 | 45篇 |
神经病学 | 493篇 |
特种医学 | 200篇 |
外科学 | 572篇 |
综合类 | 116篇 |
一般理论 | 3篇 |
预防医学 | 526篇 |
眼科学 | 49篇 |
药学 | 256篇 |
1篇 | |
中国医学 | 13篇 |
肿瘤学 | 435篇 |
出版年
2022年 | 19篇 |
2021年 | 46篇 |
2020年 | 27篇 |
2019年 | 68篇 |
2018年 | 88篇 |
2017年 | 67篇 |
2016年 | 78篇 |
2015年 | 77篇 |
2014年 | 118篇 |
2013年 | 169篇 |
2012年 | 154篇 |
2011年 | 212篇 |
2010年 | 154篇 |
2009年 | 152篇 |
2008年 | 190篇 |
2007年 | 235篇 |
2006年 | 226篇 |
2005年 | 207篇 |
2004年 | 170篇 |
2003年 | 157篇 |
2002年 | 160篇 |
2001年 | 154篇 |
2000年 | 157篇 |
1999年 | 158篇 |
1998年 | 108篇 |
1997年 | 110篇 |
1996年 | 93篇 |
1995年 | 87篇 |
1994年 | 63篇 |
1993年 | 61篇 |
1992年 | 99篇 |
1991年 | 82篇 |
1990年 | 80篇 |
1989年 | 119篇 |
1988年 | 93篇 |
1987年 | 102篇 |
1986年 | 77篇 |
1985年 | 84篇 |
1984年 | 54篇 |
1983年 | 57篇 |
1982年 | 44篇 |
1981年 | 48篇 |
1980年 | 36篇 |
1979年 | 39篇 |
1978年 | 37篇 |
1977年 | 25篇 |
1976年 | 22篇 |
1974年 | 17篇 |
1973年 | 18篇 |
1971年 | 15篇 |
排序方式: 共有5036条查询结果,搜索用时 15 毫秒
71.
Frisoni GB Rozzini L Gozzetti A Binetti G Zanetti O Bianchetti A Trabucchi M Cummings JL 《Dementia and geriatric cognitive disorders》1999,10(2):130-138
INTRODUCTION: Behavioral disturbances in patients with Alzheimer's disease (AD) are ill-defined conditions. We hypothesize that the many behavioral disturbances hitherto described and studied might be grouped into few syndromes with separate determinants and correlates. PATIENTS AND METHODS: 162 consecutive patients with probable AD admitted to a dementia unit were assessed by the UCLA Neuropsychiatric Inventory (NPI). RESULTS: Factor analysis was carried out on NPI subscales, leading to three syndromes: 'mood', 'psychotic' and 'frontal'. Patients with the 'psychotic' syndrome were older, had older age at dementia onset, had poorer cognition, were more often males, and had faster rate of dementia progression. Patients with the 'frontal' syndrome had higher education, longer disease duration, and slower rate of progression. DISCUSSION: Some combinations of behavioral disturbances occur more frequently together and might represent separate behavioral syndromes. Different clinical correlates of the syndromes suggest separate etiologies. 相似文献
72.
73.
J Menzin K Lang M Friedman P Neumann J L Cummings 《The American journal of geriatric psychiatry》1999,7(4):300-308
Although state Medicaid programs may bear a large portion of the costs of Alzheimer's disease (AD), current information on spending is not available. Using a health insurance claims database for a 10% random sample of California Medicaid ("Medi-Cal") recipients 60+ years of age, the authors estimated the excess cost of AD to Medi-Cal in 1995 as the difference in expenditures between an AD cohort (those with AD or related dementias) and an age- and sex-matched cohort without AD. Among 62,450 recipients, 2,575 (4.1%) were found to have AD or related dementias, and their average payments were approximately $7,700 higher (P<0.01) than those for the comparison group. These estimates suggest that Medi-Cal spends about $200 million on AD and related dementias annually, a burden that represents nearly 10% of state spending on elderly patients. 相似文献
74.
Shekarriz B Upadhyay J Wood DP Hinman J Raasch J Cummings GD Grignon D Littrup PJ 《Urology》1999,54(6):1044-1048
Objectives. To assess the role of clinical parameters and pathologic stage in predicting a positive vesicourethral anastomosis (VUA) biopsy in patients with a rising prostate-specific antigen (PSA) level after radical prostatectomy.Methods. Forty-five patients were referred for a rising PSA level after radical prostatectomy. Transrectal ultrasound evaluation included visualization of the VUA and VUA quadrant biopsies. The rate of positive biopsies (per core and per patient) was correlated with race, PSA level, and the radical prostatectomy pathologic stage.Results. Overall, 53% of patients had a positive biopsy. In multivariate analysis, the dominant independent and synergistic clinical parameters determining positive biopsy rates were a PSA greater than 1 ng/mL at the time of biopsy and the pathologic stage (P = 0.04 and P = 0.02, respectively). Using a PSA cutoff point of 1.0 ng/mL, those patients with organ-confined disease and a PSA of 1.0 ng/mL or less showed no positive cancer cores (low-risk group). Conversely, 89% of patients with extraprostatic extension and a PSA greater than 1.0 ng/mL had a positive biopsy (P <0.01) (high-risk group). Patients with organ-confined disease and a PSA greater than 1.0 ng/mL or extraprostatic extension and a PSA 1.0 ng/mL or less (intermediate-risk group) had a significantly higher chance of having residual cancer than the low-risk group (P <0.025).Conclusions. The PSA level at the time of biopsy and the pathologic stage of the radical prostatectomy specimen were the strongest determinants of a positive biopsy. A combination of PSA and pathologic stage is useful for decisions regarding VUA biopsy. Patients with organ-confined disease and a PSA of 1.0 ng/mL or less do not appear to benefit from a VUA biopsy, and patients with extraprostatic extension and a PSA greater than 1.0 ng/mL have such a high probability (89%) of local recurrence at the VUA that biopsy may be unnecessary. It appears that VUA biopsy can be restricted to those patients with an intermediate risk (organ-confined disease with PSA greater than 1 ng/mL or extraprostatic extension with a PSA less than 1 ng/mL). 相似文献
75.
76.
Although closed femoral osteotomy for shortening or correction of deformity is not a new procedure, its popularity apparently is increasing. We have encountered a serious "biological" complication that should be considered before this technique is selected. Two patients, a 12-year-old girl and an 18-year-old man, developed findings consistent with the fat embolism syndrome after closed femoral shortening. We suggest consideration of postoperative monitoring with pulse oximetry of patients undergoing this procedure. 相似文献
77.
Cawthorn M Cummings GS Walker JR Donatelli RA 《The Journal of orthopaedic and sports physical therapy》1991,14(2):75-81
The purpose of this study was to determine the ankle position at which the greatest peak torque occurs during isokinetic testing of inversion and eversion force. Testing of right foot invertors and evertors was performed at 10 degrees dorsiflexion, neutral dorsiflexion and plantarflexion, and 10 degrees plantarflexion on 25 untrained subjects with the MERAC isokinetic dynamometer. Subjects were retested to determine reliability. Results indicate that 10 degrees plantarflexion appears better than the other positions tested because reliability was highest and torque output was greatest at this position. Reliability was assessed with a Pearson product moment test and a paired comparisons test (p = .05). A randomized block design and a Scheffé post hoc test demonstrated that significant differences in peak torque of both invertor and evertor muscles were found between the three testing positions (p = .01). No significant difference in the invertor to evertor force ratio wits found between the three testing positions. J Orthop Sports Phys Ther 1991;14(2):75-81. 相似文献
78.
F J Cummings C H Park H A Bogaars A E Kalderon I Melnicoff S R Kaplan I Diamond P Calabresi 《Medical and pediatric oncology》1979,7(2):181-190
Successful therapy for a case of multiple myeloma with a spontaneously crystallizing cryoglobulin of the IgG2-kappa light chain variety was achieved, using both continuous-flow cell centrifugation plasmapheresis to rapidly lower the M component and combination chemotherapy with phenylalanine mustard, prednisone, procarbazine, and vincristine to control the myeloma process. This resulted in resolution of incapacitating large and small necrotic cutaneous ulcerations of the extremities. Physicochemical studies of the crystalcryoprotein demonstrated that cryoprecipitation was rapid and accompanied by the formation of needle-shaped crystals, yet was completely reversible at 37 degrees C. Cryocrit determinations varied depending upon relative centrifugal forces and temperature and did not always relate linearly to the amount of abnormal protein, thus making these alone unreliable in assessing response to therapy. 相似文献
79.
80.