全文获取类型
收费全文 | 1125146篇 |
免费 | 72256篇 |
国内免费 | 1838篇 |
专业分类
耳鼻咽喉 | 15736篇 |
儿科学 | 31812篇 |
妇产科学 | 29187篇 |
基础医学 | 158227篇 |
口腔科学 | 34204篇 |
临床医学 | 96119篇 |
内科学 | 218343篇 |
皮肤病学 | 23818篇 |
神经病学 | 84627篇 |
特种医学 | 47088篇 |
外国民族医学 | 176篇 |
外科学 | 180456篇 |
综合类 | 19167篇 |
现状与发展 | 1篇 |
一般理论 | 244篇 |
预防医学 | 78150篇 |
眼科学 | 25645篇 |
药学 | 86132篇 |
5篇 | |
中国医学 | 2357篇 |
肿瘤学 | 67746篇 |
出版年
2018年 | 13014篇 |
2017年 | 11283篇 |
2016年 | 11327篇 |
2015年 | 13899篇 |
2014年 | 16646篇 |
2013年 | 21693篇 |
2012年 | 34671篇 |
2011年 | 30905篇 |
2010年 | 17636篇 |
2009年 | 18496篇 |
2008年 | 27823篇 |
2007年 | 29664篇 |
2006年 | 30557篇 |
2005年 | 37290篇 |
2004年 | 37748篇 |
2003年 | 32605篇 |
2002年 | 27484篇 |
2001年 | 58437篇 |
2000年 | 58330篇 |
1999年 | 51852篇 |
1998年 | 11333篇 |
1997年 | 9815篇 |
1996年 | 9995篇 |
1995年 | 9347篇 |
1994年 | 8653篇 |
1993年 | 7890篇 |
1992年 | 41175篇 |
1991年 | 39891篇 |
1990年 | 38925篇 |
1989年 | 37779篇 |
1988年 | 34525篇 |
1987年 | 33529篇 |
1986年 | 31390篇 |
1985年 | 29703篇 |
1984年 | 20925篇 |
1983年 | 17667篇 |
1982年 | 8698篇 |
1979年 | 19184篇 |
1978年 | 12723篇 |
1977年 | 10676篇 |
1976年 | 9283篇 |
1975年 | 10905篇 |
1974年 | 13328篇 |
1973年 | 12400篇 |
1972年 | 11904篇 |
1971年 | 11400篇 |
1970年 | 10794篇 |
1969年 | 10201篇 |
1968年 | 9284篇 |
1967年 | 8531篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
991.
T Helme 《Journal of medical ethics》1991,17(1):25-29
In view of the continuing debate on euthanasia, the restrictions and safeguards which were introduced into the Voluntary Euthanasia (Legislation) Bill 1936 are discussed. Proposals for a new Terminal Care and Euthanasia Bill are suggested, based on some of the principles of the Mental Health Act 1983. 相似文献
992.
M Fukumizu T Kurokawa H Yoshikawa S Hanaoka 《No to hattatsu. Brain and development》1991,23(6):617-622
A seven-month-old girl with atypical West syndrome with pedaling automatism was reported. She started to have early infantile epileptic encephalopathy with suppression-burst (EIEE) at age 14 days followed by infantile spasms at 3 months of age. She began to have spasms with automatism at 4 month, mainly consisting of pedaling movements of both feet associated with tonic spasms of upper extremities and writhing of trunk. Ictal EEG showed irregular slow waves with occasional spikes predominantly over the right hemisphere mixed with artifacts. Interictal EEG during sleep showed suppression-burst patterns. Cerebral atrophy and microcephaly were revealed on brain CT, immature myelination on MRI and decreased blood flow in the frontal, temporal, and parietal lobes on the right on PET scan. Pedaling automatism is rare in infancy and its clinical significance was discussed in relation to West syndrome and complex partial seizures. 相似文献
993.
V L Towle J C Witt S H Nader A T Reder R Foust J P Spire 《Electroencephalography and clinical neurophysiology》1991,80(5):339-346
Pattern visual evoked potentials were obtained from 46 patients with definite relapsing/remitting multiple sclerosis, using both a conventional 5-channel occipital array and a 3-D recording technique consisting of three bipolar derivations approximating the three dimensions of space. These three orthogonal wave forms were displayed as a 3-D Lissajous trajectory for each subject. Two of the 15 patients with completely normal conventional pattern VEPs had abnormalities of the orientation of the B-C curvilinear segment of the 3-D pattern VEPs. Delays in the first major occipital positive component (P100) were evident using both techniques; the correlation between P100 latency and the latency of the corresponding trajectory apex was r = 0.99 (P less than 0.01). Post-chiasmal MRI abnormalities were associated with 3-D VEP orientation abnormalities. Three-dimensional pattern VEPs are moderately more sensitive than conventional pattern VEPs at detecting dysfunction posterior to the optic chiasm in demyelinating disease and do not require the use of eccentric fixation to do so. 相似文献
994.
Pulse cyclophosphamide for severe neuropsychiatric lupus. 总被引:5,自引:0,他引:5
D T Boumpas H Yamada N J Patronas D Scott J H Klippel J E Balow 《The Quarterly journal of medicine》1991,81(296):975-984
We studied the effect of parenteral pulse cyclophosphamide therapy in nine patients with active systemic lupus erythematosus and severe central nervous system involvement. Seven patients had focal neurological deficits and/or seizures associated with abnormalities on cerebrospinal fluid analysis and/or magnetic resonance imaging. Two patients had organic brain syndrome with psychosis and normal cerebrospinal fluid and/or magnetic resonance imaging analysis. Six patients were unresponsive to treatment with high dose corticosteroid. Cyclophosphamide, 0.75-1.0 g/m2 body surface area, was administered intravenously every month for at least 2 months. Eight patients had a complete recovery or recovered with minor residuals. Cyclophosphamide was well tolerated with few side effects. We conclude that parenteral pulse cyclophosphamide is an effective adjunctive therapy for the management of patients with active systemic lupus erythematosus and central nervous system symptoms. 相似文献
995.
996.
Human exposure to 3-carene by inhalation: toxicokinetics, effects on pulmonary function and occurrence of irritative and CNS symptoms 总被引:5,自引:0,他引:5
Terpenes, especially 3-carene, may irritate the skin and mucous membranes and prolonged exposure may result in allergic contact dermatitis or chronic lung function impairment. The toxicokinetics of 3-carene were studied in human volunteers exposed by inhalation (2 hr 50 W) in an exposure chamber on three occasions. The exposure concentrations were approximately 10, 225, and 450 mg/m3 3-carene. The relative pulmonary uptake was high, approximately 70% for the higher exposure levels. Total uptake increased linearly with increasing exposure. The blood clearance of 3-carene observed in this study, 0.9 liter.kg-1.hr-1, indicates that 3-carene is fairly readily metabolized. About 3% of the total uptake was eliminated unchanged via the lungs while less than 0.001% was eliminated in the urine after the end of exposure. A long half time in blood was observed in the terminal phase which indicates a high affinity to adipose tissues. A statistically significant divergence between ratings of irritation during the high exposure level and during the medium and control levels was observed. The difference in airway resistance after exposure to a high concentration of 3-carene compared to control level was not significant (P = 0.02). 相似文献
997.
Following an encephalopathic illness, a 13-year-old Chinese boy had a partial form of Klüver-Bucy syndrome with emotional disturbance, recent memory loss, hypersexuality, and polyphagia. Other unusual features included narcolepsy, polydipsia, and polyuria. Virologic studies failed to incriminate the etiologic agent, including herpes simplex virus. Brain biopsy of the frontal lobe demonstrated Alzheimer type II astrocytosis. 相似文献
998.
999.
A McRae S Hjorth D W Mason L Dillon T R Tice 《Journal of neural transplantation & plasticity》1991,2(3-4):165-173
Biodegradable controlled-release microsphere systems made with the biocompatible biodegradable polyester excipient poly [DL lactide-co-glycolide] constitute an exciting new technology for drug delivery to the central nervous system (CNS). The present study describes functional observations indicating that implantation of dopamine (DA) microspheres encapsulated within two different polymer excipients into denervated-striatal tissue assures a prolonged release of the transmitter in vivo. Moreover, in this regard, the results show that there were clear cut temporal differences in the effect of the two DA microsphere formulations compared in this study, probably reflecting variations in the actual composition (i.e., lactide to glycolide ratio) of the two copolymer excipients examined. This technology has considerable potential for basic research with possible clinical application. 相似文献
1000.
B T Hyman J E Flory S E Arnold G W Van Hoesen R L Schelper H Ghanbari H Haigler 《Journal of geriatric psychiatry and neurology》1991,4(4):231-235
A quantitative assay for ALZ-50 immunoreactivity was evaluated in samples of superior temporal gyrus taken at autopsy from 13 Alzheimer patients and 11 controls. The assayable immunoreactivity appears to be stable for at least 24 hours postmortem but was lost with formalin fixation. The mean value of the Alzheimer patients was tenfold higher than that of the controls (P less than .002). The values of four Alzheimer samples overlapped with the low levels seen in controls, but no controls had elevated levels. In this sample population, therefore, the assay had a sensitivity of 69% and specificity of 100%. 相似文献