全文获取类型
收费全文 | 986篇 |
免费 | 38篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 37篇 |
妇产科学 | 32篇 |
基础医学 | 84篇 |
口腔科学 | 17篇 |
临床医学 | 151篇 |
内科学 | 174篇 |
皮肤病学 | 28篇 |
神经病学 | 30篇 |
特种医学 | 152篇 |
外科学 | 97篇 |
综合类 | 52篇 |
预防医学 | 74篇 |
眼科学 | 16篇 |
药学 | 28篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 54篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 15篇 |
2020年 | 5篇 |
2019年 | 10篇 |
2018年 | 15篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 36篇 |
2014年 | 62篇 |
2013年 | 36篇 |
2012年 | 42篇 |
2011年 | 65篇 |
2010年 | 34篇 |
2009年 | 44篇 |
2008年 | 57篇 |
2007年 | 62篇 |
2006年 | 72篇 |
2005年 | 46篇 |
2004年 | 43篇 |
2003年 | 44篇 |
2002年 | 36篇 |
2001年 | 17篇 |
2000年 | 13篇 |
1999年 | 12篇 |
1998年 | 18篇 |
1997年 | 17篇 |
1996年 | 22篇 |
1995年 | 21篇 |
1994年 | 29篇 |
1993年 | 13篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1989年 | 12篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1985年 | 22篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 3篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 7篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1969年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有1030条查询结果,搜索用时 15 毫秒
71.
Bedrov YA Dik OE Bobrova EV Gerasimenko YP 《Bulletin of experimental biology and medicine》2003,136(3):311-313
According to current concepts, two processes are responsible for the maintenance of body equilibrium: shifts of the reference point caused by changes in the posture and stabilization of oscillations of the center of mass relative to this point. Exact changes in these processes occurring at various forms of locomotor disorders remain unclear. We proposed an original mathematical method allowing separate evaluation of these two processes responsible for the maintenance of body equilibrium. 相似文献
72.
van Boven M Veldman KT de Jong MC Mevius DJ 《The Journal of antimicrobial chemotherapy》2003,52(4):719-723
OBJECTIVE: To determine the within-host population dynamics of Campylobacter jejuni and Escherichia coli in chickens during and after treatment with fluoroquinolones. MATERIALS AND METHODS: Total and resistant faecal counts were determined from cloacal swabs during and after treatment with enrofloxacin. Chickens were housed individually to avoid confounding as a result of interaction between animals, and to be able to focus solely on the within-host dynamics. To determine the molecular basis of resistance, a number of isolates were checked for mutations in gyrA. RESULTS: Treatment with enrofloxacin at doses routinely prescribed (50 ppm) rapidly reduced the faecal counts of E. coli below the detection limit and did not induce resistance. In C. jejuni, on the other hand, treatment with enrofloxacin quickly selected for high frequencies of fluoroquinolone-resistant strains. In all phenotypically resistant isolates, resistance was traced to mutations in the gyrA gene. CONCLUSIONS: (1) A licensed dosage (50 ppm) of enrofloxacin in drinking water of chickens is effective (i.e. markedly reduced faecal counts) and is safe on a short time scale in E. coli (i.e. did not rapidly select for resistance), but is neither safe nor effective in C. jejuni. (2) The rapid emergence of resistance to quinolones in C. jejuni does not necessarily result from horizontal transmission of resistant strains among chickens, but could solely be the result of de novo selection of resistance in individual chickens. 相似文献
73.
74.
Short course dexamethasone treatment following injury inhibits bleomycin induced fibrosis in rats 总被引:8,自引:0,他引:8
下载免费PDF全文
![点击此处可从《Thorax》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dik WA McAnulty RJ Versnel MA Naber BA Zimmermann LJ Laurent GJ Mutsaers SE 《Thorax》2003,58(9):765-771
BACKGROUND: Corticosteroids are routinely used in patients with pulmonary fibrosis. The timing for initiation of treatment is likely to be crucial for corticosteroids to exert an antifibrotic effect. Experimental studies in animals have examined the effect of corticosteroid treatment starting before or at the time of lung injury. However, this is not representative of the human condition as treatment only begins after disease has been established. We examined the effect of a short course corticosteroid treatment starting 3 days after bleomycin induced lung injury on the development of pulmonary fibrosis. METHODS: Bleomycin (1.5 mg/kg) was instilled intratracheally into rats to induce pulmonary fibrosis. The effect of a 3-day course of dexamethasone (0.5 mg/kg) initiated 3 days after bleomycin induced lung injury on cell proliferation and collagen deposition was examined by analysing bronchoalveolar lavage (BAL) fluid and lung tissue. RESULTS: Treating bleomycin exposed animals after injury with dexamethasone for 3 days inhibited lung collagen deposition compared with animals exposed to bleomycin without dexamethasone treatment (15.2 (2.2) mg collagen/lung v 22.5 (2.1) mg/lung; p<0.05). Dexamethasone treatment reduced pulmonary parenchymal cell proliferation in bleomycin exposed rats but did not influence BAL fluid mitogenic activity for lung fibroblasts or alter the BAL fluid levels of the fibrogenic mediators transforming growth factor-beta(1), platelet derived growth factor-AB, and thrombin. CONCLUSIONS: A 3 day course of dexamethasone treatment initiated 3 days after bleomycin induced lung injury reduces lung cell proliferation and collagen deposition by mechanisms other than through reduction of transforming growth factor-beta(1), platelet derived growth factor-AB, and thrombin levels in BAL fluid. We propose that an early short course treatment with dexamethasone may be useful in inhibiting pulmonary fibrosis. 相似文献
75.
Bladder-sphincter dysfunction in myelomeningocele 总被引:5,自引:0,他引:5
Pediatric urodynamics taught us that detrusor-sphincter dyssynergia creates a bladder outlet obstruction in about 50% of
any population of children with myelomeningocele. This functional obstruction causes renal damage due to obstructive uropathy,
exactly the same way as a congenital anatomical urethral obstruction does. Pediatric urodynamics also taught us that in children
with myelomeningocele pelvic floor activity and detrusor activity can be abnormal (hyperactive or inactive) completely independent
from each other. These insights have changed the management of myelomeningocele. Children with overactivity of the pelvic
floor can be singled out at infant age, and started on clean intermittent catherization, to prevent obstructive uropathy and
preserve renal function. Children with detrusor overactivity can be singled out too at very early age, and treated with anticholinergics,
to prevent irreversible structural damage to the detrusor and preserve normal bladder capacity and compliance.
Received: 20 July 1999 / Accepted: 24 January 2001 相似文献
76.
Orroth KK Korenromp EL White RG Gavyole A Gray RH Muhangi L Sewankambo NK Quigley M Wawer MJ Whitworth JA Grosskurth H Habbema JD Hayes RJ 《AIDS (London, England)》2003,17(18):2653-2660
OBJECTIVE: To determine to what extent the higher impact of treatment for sexually transmitted diseases (STD) on HIV incidence in Mwanza, Tanzania than in Rakai and Masaka, Uganda might be explained by baseline differences between the trial populations. DESIGN: A re-analysis of baseline data from the three trial populations comparing demography, sexual risk behaviour and HIV/STD epidemiology. METHODS: Data were compared after age-standardization and adjustments for sample selection where necessary. STD rates were also adjusted for the sensitivities and specificities of the diagnostic techniques used. RESULTS: Demographic patterns were similar across populations, apart from effects of AIDS on fertility and mortality (including widowhood) in Uganda. Higher sexual risk behaviours, including younger age of sexual debut, higher numbers of recent partners and lower frequency of condom use, were apparent in Mwanza compared to Masaka and Rakai. High-titre serological syphilis, gonorrhoea, chlamydia infection and trichomoniasis were all more prevalent in Mwanza, except for chlamydia infection in males. There was little difference between sites in the seroprevalence of Herpes simplex virus type-2. Age patterns in the prevalence of short-duration STD and current risk behaviours were similar across sites but all-titre serological syphilis was more prevalent among older participants in Rakai and Masaka than Mwanza. CONCLUSIONS: Differences between trial populations included higher reported risk behaviour and higher rates of curable STD in Mwanza compared to Rakai and Masaka. These differences probably relate to previous reductions in risk behaviour in Uganda and may explain, at least in part, the contrasting results of these trials. 相似文献
77.
Endomyocardial biopsy was attempted in 18 children aged 5 months to 15 years with 82% success. Biopsies obtained from 15 children were examined by light and electron microscope making positive morphological diagnoses in 3 cases. The biopsy findings were actively helpful in 7 other cases, which contrasts with experience in adult biopsy series. This is a low risk procedure which does not add to the hazards of cardiac catheterization in children. 相似文献
78.
DP Southall WA Arrowsmith JR Oakley G McEnery RH Anderson EA Shinebourne 《Archives of disease in childhood》1979,54(10):776-779
Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS. 相似文献
79.
High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases. 相似文献
80.
Management of cerebral ischemia due to Takayasu''''s arteritis 总被引:2,自引:0,他引:2
Aortoarteritis ,alsocalledTakayasu’sarteritis ,isachronicidiopathicinflammatorydiseasethataffectslargeandmediumsizearteries Clinicalfeaturesreflectlimbororganischemiaresultingfromstenosistoobliterationofinvolvedarteries Thisdisease ,describedbyTakayasuin… 相似文献