全文获取类型
收费全文 | 933篇 |
免费 | 34篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 19篇 |
妇产科学 | 65篇 |
基础医学 | 86篇 |
口腔科学 | 16篇 |
临床医学 | 128篇 |
内科学 | 202篇 |
皮肤病学 | 30篇 |
神经病学 | 49篇 |
特种医学 | 7篇 |
外科学 | 96篇 |
综合类 | 33篇 |
一般理论 | 1篇 |
预防医学 | 107篇 |
眼科学 | 10篇 |
药学 | 72篇 |
肿瘤学 | 28篇 |
出版年
2016年 | 5篇 |
2015年 | 9篇 |
2014年 | 10篇 |
2013年 | 26篇 |
2012年 | 6篇 |
2010年 | 32篇 |
2009年 | 21篇 |
2008年 | 8篇 |
2001年 | 11篇 |
2000年 | 7篇 |
1999年 | 11篇 |
1998年 | 20篇 |
1997年 | 39篇 |
1996年 | 44篇 |
1995年 | 25篇 |
1994年 | 23篇 |
1993年 | 21篇 |
1992年 | 27篇 |
1991年 | 22篇 |
1990年 | 22篇 |
1989年 | 15篇 |
1988年 | 25篇 |
1987年 | 23篇 |
1986年 | 13篇 |
1985年 | 22篇 |
1984年 | 14篇 |
1983年 | 16篇 |
1982年 | 23篇 |
1981年 | 14篇 |
1980年 | 12篇 |
1979年 | 10篇 |
1978年 | 10篇 |
1977年 | 11篇 |
1976年 | 5篇 |
1975年 | 8篇 |
1973年 | 5篇 |
1972年 | 6篇 |
1971年 | 5篇 |
1969年 | 7篇 |
1965年 | 5篇 |
1963年 | 6篇 |
1959年 | 31篇 |
1958年 | 43篇 |
1957年 | 31篇 |
1956年 | 32篇 |
1955年 | 29篇 |
1954年 | 44篇 |
1949年 | 18篇 |
1948年 | 34篇 |
1946年 | 8篇 |
排序方式: 共有968条查询结果,搜索用时 15 毫秒
11.
Oral rehydration solutions (ORS) are widely promoted as a treatmentfor the dehydration associated with childhood diarrhoea. Manynational and global programmes have adopted ORS use rates derivedfrom surveys as their principal indicator of programme success.However, such widespread reliance on ORS use rates is ill-advised.The rate is very sensitive to the way the survey questions areasked. Discussed here are the terms identifying diarrhoeal episodes,the length of the reference period, and the ordering of questionsabout treatment practices. Furthermore, ORS rates are frequentlyused inappropriately, often in situations in which treatmentof a proportion of all diarrhoeal episodes is not the principalobjective. 相似文献
12.
The effect of the vehicle on the permeation rate of nickel ions through excised human skin was evaluated. Different hydrogels were compared with the standard patch test in petrolatum. A hydroxypropyl methylcellulose gel seemed to be the most promising alternative to petrolatum. It gave high bioavailability of the nickel and had good film forming properties leaving the nickel spread across the skin surface as a thin film without microscopically detectable crystals. The content of nickel in the various skin layers after cutaneous application was determined, and nickel was found to accumulate in the epidermis, probably due to epidermal binding. A significant amount of nickel was found also in the dermis. Occlusion and application of higher nickel concentrations increased the transport rate and must be considered in patch testing using this hydrogel. We conclude that nickel permeation is highly dependent of the choice of vehicle and the vehicle should, therefore, be an important consideration in patch testing with nickel. 相似文献
13.
STEVEN R. COHEN MD CARL F. BERNER MD MARIANO BUSSO MD PAUL CLOPTON MS DOUGLAS HAMILTON MD JAMES J. ROMANO MD PETER P. RULLAN MD MILLARD P. THALER MD ZEENA UBOGY MD THOMAS R. VECCHIONE MD 《Dermatologic surgery》2007,33(S2):S222-S230
BACKGROUND A novel soft tissue filler composed of polymethylmethacrylate (PMMA) microspheres suspended in a collagen gel matrix containing 0.3% lidocaine (ArteFill, Artes Medical, Inc.) was recently approved by the Food and Drug Administration for the correction of nasolabial folds. A randomized, multicenter, controlled pivotal trial performed in the United States established the safety and efficacy of this medical device throughout a 12-month study period.
OBJECTIVE The objective was to substantiate the long-term 5-year safety and efficacy of this novel soft tissue PMMA filler.
METHODS AND MATERIALS Attempts were made to contact all subjects treated with the PMMA filler that were enrolled in the original pivotal study. Safety was assessed by standard adverse event reporting methods. Efficacy was determined using a validated six-point facial fold assessment photometric grading scale using blinded observers' assessment of standardized photographs.
RESULTS Subjects ( n =119) demonstrated significant improvement in nasolabial folds comparing baseline (before any treatment) to 5 years after their last treatment ( p <.001). Notably, subjects also demonstrated continued improvement between 6 months after their last treatment and Year 5 ( p =.002). No serious unanticipated device-related adverse events were reported.
CONCLUSION This PMMA filler is the first soft tissue filler to demonstrate continued improvement and persistence of correction over a 5-year period posttreatment. 相似文献
OBJECTIVE The objective was to substantiate the long-term 5-year safety and efficacy of this novel soft tissue PMMA filler.
METHODS AND MATERIALS Attempts were made to contact all subjects treated with the PMMA filler that were enrolled in the original pivotal study. Safety was assessed by standard adverse event reporting methods. Efficacy was determined using a validated six-point facial fold assessment photometric grading scale using blinded observers' assessment of standardized photographs.
RESULTS Subjects ( n =119) demonstrated significant improvement in nasolabial folds comparing baseline (before any treatment) to 5 years after their last treatment ( p <.001). Notably, subjects also demonstrated continued improvement between 6 months after their last treatment and Year 5 ( p =.002). No serious unanticipated device-related adverse events were reported.
CONCLUSION This PMMA filler is the first soft tissue filler to demonstrate continued improvement and persistence of correction over a 5-year period posttreatment. 相似文献
14.
THE NATURE OF ARTHRITIS PAIN 总被引:1,自引:0,他引:1
CHARTER RICHARD A.; NEHEMKIS ALEXIS M.; KEENAN MARY ANN; PERSON DENISE; PRETE PAMELA E. 《Rheumatology (Oxford, England)》1985,24(1):53-60
A modified version of the McGill Pain Questionnaire in visualanalogue format was used to evaluate the sensory, affectiveand evaluative intensities of pain experienced by 40 patientswith rheumatoid arthritis and 20 patients with degenerativearthritis. The affective component of the pain was found tobe more intense than the sensory component in all patients indicatingthe importance of emotional factors in the pain experience.The sensory aspects of the pain were more complex than the affectiveones reflecting the varied sources and combinations of somaticpathology. There were no significant differences found in theoverall pain experience between rheumatoid and degenerativearthritis. No differences were noted in the evaluative categoryof pain. Overall pain intensity increased with disease durationin both rheumatoid and degenerative arthritis. The relationshipof affective and sensory components of the pain experience didnot alter with duration of disease. KEY WORDS: Arthritis, Pain 相似文献
15.
PITUITARY ACTH DEPENDENT CUSHING''S SYNDROME DUE TO ECTOPIC PRODUCTION OF A BOMBESIN-LIKE PEPTIDE BY A MEDULLARY CARCINOMA OF THE THYROID 总被引:2,自引:1,他引:2
T. A. HOWLETT JANET PRICE ANN C. HALE I. DONIACH LESLEY H. REES J. A. H. WASS G. M. BESSER 《Clinical endocrinology》1985,22(1):91-101
A 41-year-old man presented with Cushing's syndrome and the biochemical features of ectopic ACTH production. Investigation revealed mediastinal metastases from a medullary carcinoma of the thyroid. The peripheral plasma contained grossly elevated levels of bombesin-like immunoreactivity (irBombesin) as well as calcitonin; blood sampling via a venous catheter confirmed a gradient of irBombesin, but not of ACTH, in the mediastinal vein draining the tumour. On extraction the tumour contained a bombesin-like peptide, but not vasopressin or corticotrophin releasing factor and only very low levels of ACTH; immunohistochemical studies showed positive immunostaining for bombesin and calcitonin but none for ACTH or CRF. No ACTH was released from dispersed tumour cells in vitro. However an extract of the tumour stimulated ACTH release in vitro from perifused dispersed rat anterior pituitary cells. This is the first reported case of Cushing's syndrome due to ectopic production of a bombesin-like peptide, causing excessive pituitary ACTH secretion. 相似文献
16.
17.
18.
INGE O. BAAS FRANK M. VAN DEN BERG JAN-WILLEM R. MULDER MARJON J. CLEMENT ROBBERT J. C. SLEBOS STANLEY R. HAMILTON G. JOHAN A. OFFERHAUS 《The Journal of pathology》1996,178(3):264-267
Aberrant crypt foci (ACF) are putative precursor lesions of colon cancer, recently identified on the methylene blue-stained mucosal surface of human colon. No mutations in K- ras or p53 genes were found by non-radioactive single-strand conformation polymorphism analysis in 14 ACF collected from five patients. Using the more sensitive method of allele-specific polymerase chain reaction (PCR) for K- ras , 8 of 14 ACF were found to contain K- ras mutations, suggesting that mutated cells are present in minute clones in ACF. No dysplasia was observed in any of the ACF containing a mutated clone. The presence of K- ras mutations in ACF suggests that these lesions occur at a very early stage in human colorectal carcinogenesis. 相似文献
19.
COLM COONEY ANN MORTIMER ANDREW SMITH KATE NEWTON MARGO WRIGLEY 《International journal of geriatric psychiatry》1996,11(10):901-905
In a randomized placebo crossover controlled study, six patients meeting DSM-III-R criteria for Alzheimer's disease and exhibiting significantly aggressive behaviour were administered carbamazepine (in doses up to 600 mg daily) and placebo, with each treatment period lasting 8 weeks. Levels of aggression as measured by the RAGE scale were significantly reduced compared with placebo (p<0.05). The results suggest that carbamazepine is an effective anti-aggressive agent in patients with dementia. Recommendations for further studies are made. 相似文献
20.
GARY W. SMALL LON S. SCHNEIDER S. H. HAMILTON ALEXANDER BYSTRITSKY BARNETT S. MEYERS CHARLES B. NEMEROFF FLUOXETINE COLLABORATIVE STUDY GROUP 《International journal of geriatric psychiatry》1996,11(12):1089-1095
We studied differences in outcome and characteristics among 29 clinical sites of a multisite, double-blind antidepressant trial for geriatric depression. Six hundred and seventy-one outpatients aged 60 years or older (mean±SD=67.7±5.7) met DSM-III-R criteria for unipolar major depression, had baseline 17-item Hamilton Depression Rating Scale (HAMD17) scores ≥16 and were randomized to fluoxetine (20 mg daily) or placebo. Effect sizes (ESs, expressed as mean differences between effects divided by the pooled standard deviation of the differences) were calculated for each site using selected outcome measures. ES ranged from 1.84 (favoring fluoxetine) to −0.91 (favoring placebo) for incidence of remitters (endpoint HAMD17 total score of ≤8). A large, positive ES favoring fluoxetine for remission rates (ES≥0.65) was found at only six sites, moderate ES (0.35–0.64) at eight and small ES (0–0.34) at seven; ES favored placebo (<0) at eight of 29 sites. Private clinics showed an overall HAMD17 ES for change scores more than twice that of university sites. These results suggest that individual practitioners may have vastly different clinical experiences in large, multisite trials for geriatric depression. Interrater reliability, subject selection, recruitment, inadequate or fixed dosing, few patients per site, brief study duration, heterogeneity of geriatric depression, financial incentive and characteristics of individual sites may contribute to response variability. 相似文献