全文获取类型
收费全文 | 1353881篇 |
免费 | 101461篇 |
国内免费 | 4485篇 |
专业分类
耳鼻咽喉 | 16956篇 |
儿科学 | 43890篇 |
妇产科学 | 36663篇 |
基础医学 | 200495篇 |
口腔科学 | 36520篇 |
临床医学 | 131264篇 |
内科学 | 263031篇 |
皮肤病学 | 26585篇 |
神经病学 | 113729篇 |
特种医学 | 48814篇 |
外国民族医学 | 366篇 |
外科学 | 186846篇 |
综合类 | 28926篇 |
现状与发展 | 1篇 |
一般理论 | 463篇 |
预防医学 | 115285篇 |
眼科学 | 29249篇 |
药学 | 100287篇 |
6篇 | |
中国医学 | 3259篇 |
肿瘤学 | 77192篇 |
出版年
2021年 | 11448篇 |
2019年 | 12116篇 |
2018年 | 16888篇 |
2017年 | 12711篇 |
2016年 | 13737篇 |
2015年 | 15746篇 |
2014年 | 21533篇 |
2013年 | 32943篇 |
2012年 | 45623篇 |
2011年 | 48324篇 |
2010年 | 27883篇 |
2009年 | 25648篇 |
2008年 | 43848篇 |
2007年 | 46286篇 |
2006年 | 46223篇 |
2005年 | 44719篇 |
2004年 | 42594篇 |
2003年 | 40407篇 |
2002年 | 39194篇 |
2001年 | 61032篇 |
2000年 | 62697篇 |
1999年 | 52458篇 |
1998年 | 14788篇 |
1997年 | 13420篇 |
1996年 | 13215篇 |
1995年 | 12563篇 |
1994年 | 11725篇 |
1993年 | 11015篇 |
1992年 | 41691篇 |
1991年 | 40831篇 |
1990年 | 39508篇 |
1989年 | 37394篇 |
1988年 | 34635篇 |
1987年 | 33747篇 |
1986年 | 32201篇 |
1985年 | 30682篇 |
1984年 | 23081篇 |
1983年 | 19622篇 |
1982年 | 11788篇 |
1979年 | 20816篇 |
1978年 | 14832篇 |
1977年 | 12076篇 |
1976年 | 11888篇 |
1975年 | 12122篇 |
1974年 | 14817篇 |
1973年 | 14495篇 |
1972年 | 13367篇 |
1971年 | 12434篇 |
1970年 | 11501篇 |
1969年 | 10419篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The cases of 33 children with hypothalamic-chiasmatic gliomas are reviewed. Radiation therapy produced clinical or radiographic improvement in 11 (46%) of 24 patients. Progression was documented in 18 patients (54%). Overall, the median time to tumor progression was 60 months; it was 70 months in patients who received radiation therapy and 30 months in those who did not (P less than 0.05). Chemotherapy, either given initially or at the time of progression, caused the tumor to respond or to stabilize in 10 patients. Partial resection of the tumor led to improvement in 3 of 12 patients, obviating the need for a shunt in 2 of them; there were no deaths and postoperative morbidity was transient and minimal (diabetes insipidus, intraventricular hemorrhage, and left hemiparesis in one patient each). The 5- and 10-year survival probabilities were 93 and 74%, respectively. Patients with neurofibromatosis had a better prognosis. 相似文献
992.
993.
D Macioce S Caruso M Oldani G L Spreafico F Cammelli G Gadola 《La Chirurgia degli Organi di Movimento》1990,75(2):163-169
The authors conducted a clinical and radiographic study on a group of 43 patients with hip arthroprostheses selected from the three-year period from 1984 to 1987, characterized by no immediate postoperative complications, no positional defects on X-ray examination, and with a Renther test greater than 1. Prostheses were cemented, cementless and combined. Scintigraphy was evaluated for areas of subdivision in the proximal end of the femur and acetabulum, making a semi-quantitative comparison of the intensity of captation of each area with that of the skull and sacroiliac synchondrosis. The authors emphasize that this procedure is both reliable and easy for the early determination (pre-clinical and pre-radiographic) of any complications. A scintigraphic examination of the single areas was also capable of revealing the site and entity of prosthetic bone-to-implant interactions. According to the results reported, PCA prostheses seem to be characterized by better biocompatibility. 相似文献
994.
A D al-Haidary I G Mackay K D Bhoola N D Millar M L Watson J C Mackenzie 《Nephrology, dialysis, transplantation》1990,5(7):535-541
Eighteen renal transplant recipients and sixteen volunteers were subjected to the physiological manoeuvre of head-out water immersion, in order to compare changes in electrolyte and humoral responses known to occur in healthy individuals with those arising as a result of renal denervation in the transplant recipients. Although the tubular sodium response to water immersion was normal, tubular potassium excretion was markedly different in the transplant patients. Plasma values of atrial natriuretic factor increased in both groups and showed a close temporal relationship to urinary excretion of cyclic GMP. The attenuation in transplant recipients of the well-documented suppression of plasma renin activity during water immersion was probably due to a combination of factors, namely lack of renal innervation and an increase in circulating ANF. The small but significant increase in the excretion of enzymically active urinary kallikrein observed only in the transplant recipients during immersion still requires explanation. 相似文献
995.
Transcutaneous oxygen measurements (TcpO2) have been shown to be an index of tissue perfusion and it has been suggested that the main haemodynamic variable influencing tissue perfusion is cardiac output, assuming that inspired oxygen remains constant. To investigate this hypothesis we studied 23 consecutive patients in order to identify if changes in cardiac output correlated with similar changes in TcpO2 measurements. No correlation was found to suggest that cardiac output was the main haemodynamic determinant of TcpO2 measurements. 相似文献
996.
C L Li 《中华整形烧伤外科杂志》1990,6(4):262-4, 317
An analysis of serum free amino acid profiles in 8 patients dying from major burns revealed that free amino acid began to decrease in shock period, decrease 31.12% in infection period and 41.3% before death in comparison with the control group. The amount of BCAA-also decrease 36.27% in infection period and 56.83% before death. If the serum free amino acid in major burn drops steadily, the prognosis will be worse. 相似文献
997.
The importance of intraoperative cholangiography during laparoscopic cholecystectomy 总被引:4,自引:0,他引:4
E H Phillips G Berci B Carroll L Daykhovsky J Sackier M Paz-Partlow 《The American surgeon》1990,56(12):792-795
Laparoscopic cholecystectomy (LC) using electrocoagulation was successfully performed in 56 out of 58 selected patients. Cholangiography was performed in 53 patients. Six patients had common duct stones; five were unsuspected preoperatively. After the gallbladder was removed, three patients underwent open common duct exploration. In another five cases, anatomical anomalies were discovered. Cholangiography performed via the cystic duct before any structures are divided can prevent the most serious complication--common duct injury. Cholangiography should be attempted on all patients undergoing LC. 相似文献
998.
In an attempt to study further the possible participation of platelets in the pathogenesis of acute poststreptococcal glomerulonephritis (APSGN), we studied the platelet survival time, as an index of platelet activation, in 22 patients with APSGN. Mean platelet survival time was computed from the disappearance of radioactivity from blood, sampled serially after injection of autologous 51Cr-labelled platelets. C1q solid phase ELISA and conglutinin (K) solid phase ELISA were used to measure the serum levels of immune complexes. The platelet survival time in APSGN patients was 113 +/- 10 h vs 197 +/- 10 h in the control group (p less than 0.001); 68% of the patients had a shortened platelet survival, lower than 95% confidence limit. There was a significant increase in the platelet survival in the six patients that were studied after recovery from acute nephritic syndrome. There was no significant association between the mean platelet times survival and CICs (circulating immune complexes). Similarly, no significant correlation was found between the mean platelet lifespan and the severity of the glomerular disease, as assessed by the serum creatinine level and the proteinuria. These results support evidence of platelet activation and consumption in APSGN and we suggest that this activation occurs in the glomeruli capillary wall, due to platelet-vascular wall interaction. 相似文献
999.
1000.
A B Fulton J Dodge J L Schremser A Armstrong F Lanier W W Dawson T P Williams 《Current eye research》1990,9(12):1211-1216
The content of rhodopsin in the eyes of 15 donors (30 eyes) was determined. Both retinal and pigment epithelial fractions were collected from each globe, extracted using 1% CTAB, and the rhodopsin difference spectrum of each fraction was obtained separately. The total amount of rhodopsin, obtained by summing the amounts recovered from the retinal and PE fractions, ranged from 2.00 to 11.94 (median: 6.40) nmoles/eye. Previously reported mean values of about 3.5 to 4.0 nmoles per retina have been obtained using a variety of methods. The present higher values, perhaps largely dependent on procedural details described herein, appear plausible given the known concentrations of rhodopsin in rod outer segments, rod outer segment volumes, and number of rods in the human retina. 相似文献