全文获取类型
收费全文 | 3159776篇 |
免费 | 230461篇 |
国内免费 | 4759篇 |
专业分类
耳鼻咽喉 | 44837篇 |
儿科学 | 104986篇 |
妇产科学 | 85884篇 |
基础医学 | 459065篇 |
口腔科学 | 86788篇 |
临床医学 | 284159篇 |
内科学 | 611571篇 |
皮肤病学 | 69644篇 |
神经病学 | 249536篇 |
特种医学 | 119996篇 |
外国民族医学 | 1096篇 |
外科学 | 477546篇 |
综合类 | 67338篇 |
现状与发展 | 12篇 |
一般理论 | 1118篇 |
预防医学 | 246832篇 |
眼科学 | 74016篇 |
药学 | 235437篇 |
12篇 | |
中国医学 | 6132篇 |
肿瘤学 | 168991篇 |
出版年
2019年 | 24973篇 |
2018年 | 34775篇 |
2017年 | 26147篇 |
2016年 | 29278篇 |
2015年 | 33019篇 |
2014年 | 46522篇 |
2013年 | 70286篇 |
2012年 | 96773篇 |
2011年 | 103009篇 |
2010年 | 61454篇 |
2009年 | 58147篇 |
2008年 | 97089篇 |
2007年 | 103734篇 |
2006年 | 104661篇 |
2005年 | 101406篇 |
2004年 | 97686篇 |
2003年 | 94256篇 |
2002年 | 91751篇 |
2001年 | 144753篇 |
2000年 | 148998篇 |
1999年 | 126078篇 |
1998年 | 36517篇 |
1997年 | 32176篇 |
1996年 | 32561篇 |
1995年 | 30886篇 |
1994年 | 28717篇 |
1993年 | 26837篇 |
1992年 | 98546篇 |
1991年 | 96560篇 |
1990年 | 93997篇 |
1989年 | 90219篇 |
1988年 | 83040篇 |
1987年 | 81829篇 |
1986年 | 76473篇 |
1985年 | 73600篇 |
1984年 | 55012篇 |
1983年 | 46714篇 |
1982年 | 27727篇 |
1981年 | 24977篇 |
1979年 | 50368篇 |
1978年 | 35731篇 |
1977年 | 30012篇 |
1976年 | 28483篇 |
1975年 | 30774篇 |
1974年 | 36493篇 |
1973年 | 34925篇 |
1972年 | 32579篇 |
1971年 | 30485篇 |
1970年 | 28422篇 |
1969年 | 26751篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
K A Phillips 《The Journal of clinical psychiatry》1991,52(12):514-515
942.
Spectral analysis of the electroencephalogram in neonatal rats chronically treated with the NMDA antagonist MK-801. 总被引:1,自引:0,他引:1
J A Gorter M Veerman M Mirmiran N P Bos M A Corner 《Brain research. Developmental brain research》1991,64(1-2):37-41
In order to study the involvement of NMDA-receptor activation in brain development, rat pups were chronically treated with the non-competitive NMDA antagonist MK-801 during the neonatal period. We recorded the cortical EEG at various vigilance states throughout the treatment period. Spectral analysis of the EEG showed reduced power in the delta (delta) frequency range (1.5-4 Hz) during quiet sleep and less power in the theta (theta) range (4-7 Hz) during REM-sleep in MK-801 animals than in controls. No significant differences were found for the total time spent in each of the different vigilance states. We conclude that chronic MK-801 treatment probably causes a developmental retardation in state-related brain activities. 相似文献
943.
C Caron J Goudemand A Marey D Beague G Ducroux F Drouvin 《Thrombosis and haemostasis》1991,66(4):410-414
The plasma levels of several haemostatic and fibrinolytic parameters were measured before and after delivery in 61 hypertensive pregnant women of whom 22 developed preeclampsia, and compared to the results obtained in 42 normal pregnant women. In the two last weeks before delivery (D less than or equal to -15) tPA antigen, PAI-1 activity, vWF:Ag/FVIII:C ratio, ATIII activity and platelet count were found to be significantly different in the hypertensive pregnant women with and without preeclampsia. Combined all together, an association of three of these five parameters were found to be pathological (i.e.:tPA:Ag greater than or equal to 19 ng/ml, PAI-1 activity greater than or equal to 58 IU/ml, vWF:Ag/FVIII:C ratio greater than or equal to 2.6, ATIII activity less than or equal to 73%) in none of the hypertensive women without preeclampsia and in only 35% of the preeclamptic group. A positive correlation was demonstrated between vWF:Ag/FVIII:C ratio and tPA:antigen levels suggesting that both tPA and vWF:Ag could be considered as early indicators of a possible micro angiopathy occurring in preeclampsia. However, due to the high dispersion of the results, it appears that the investigated haemostatic and/or fibrinolytic criteria give only presumptive arguments before assigning risk for preeclampsia development among hypertensive pregnant women. 相似文献
944.
945.
A total of 102 patients were examined, 32 of these with true eczema, 38 with exudative mycosis of the soles, and 32 with eczema etiologically related to a fungal infection. Analysis of the immune and biochemical reactions in the examinees has shown a marked reduction of adenyl nucleotides in the leukocytic suspension and neutrophils of patients with a mycotic infection as against those with true eczema. The lowest creatine phosphate levels were detected in the leukocytic suspension and neutrophils of the patients suffering from eczema etiologically related to mycosis and exudative mycosis of the soles. These results give grounds to search for effective corrective therapy. 相似文献
946.
This paper discusses the application of intravenous Kalipsol anesthesia in combination with Seduxen (Relanium) in 22 patients who underwent antro-mastoidectomy (expanded) and fronto-ethmoidectomy. No complications related to the method of anesthesia were identified. It is concluded that the use of Kalipsol anesthesia in urgent ENT operations provides better surgical intervention. This method ensures adequate analgesia during operation. 相似文献
947.
P G Crosignani A M Mattei C Scarduelli V Cavioni P Boracchi 《Human reproduction (Oxford, England)》1989,4(8):910-912
This paper reports the changes in prolactin levels after 12 spontaneous and 52 induced pregnancies in 54 women with unambiguous hyperprolactinaemia (median plasma prolactin levels 67.5 ng/ml, range 40-400). Twenty-three of the patients showed radiological evidence of prolactinoma. The pregnancies were induced in 37 patients by bromocriptine, in nine by metergoline, in two by lisuride and in four by other treatments. Of the 64 pregnancies, 16 ended in spontaneous abortion, while 48 went to term. Follow-up was continued for at least 6 months after delivery or until the end of lactation. In a control group of 32 hyperprolactinaemic women (median prolactin 70 ng/ml, range 40-400) not wishing to become pregnant, prolactin changes were similarly registered over a mean period of 15 months without any treatment (range 6-38 months). After pregnancy, a significant downward trend of plasma prolactin was observed in the puerperal women with a 'normalization' rate of 17%. No changes were observed in the 32 controls who did not become pregnant. 相似文献
948.
949.
Department of Biology, Izhevsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR D. S. Sarkisov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 3, pp. 353–356, March, 1989. 相似文献
950.
J M Debets R Kampmeijer M P van der Linden W A Buurman C J van der Linden 《Critical care medicine》1989,17(6):489-494
Tumor necrosis factor (TNF) cachectin has been implicated as an important host mediator responsible for shock and multiple organ failure (MOF) observed during sepsis. Using a sensitive enzyme-linked immunosorbent assay, we measured plasma TNF levels in 43 septic patients suffering from a broad range of diseases. Measurements were taken on the day that sepsis was diagnosed. Eleven patients had detectable TNF plasma levels ranging from 10 to 100 pg/ml (TNF-positive group); in 32 patients circulating TNF could not be detected (TNF-negative group). The groups did not differ significantly as to age, underlying disease, percentage positive bacteremia and bacteriologic profile, sepsis score, and extent of MOF. Eight (73%) of 11 TNF-positive patients died from sepsis during ICU stay, vs. 11 (34%) of 32 TNF-negative patients (p less than .05). This study demonstrates that sepsis is accompanied by detectable circulating TNF in 25% of the cases, and for these patients mortality is twice that for comparable TNF-negative patients. 相似文献