首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   302篇
  免费   10篇
  国内免费   6篇
儿科学   15篇
妇产科学   1篇
基础医学   24篇
口腔科学   11篇
临床医学   21篇
内科学   113篇
皮肤病学   4篇
神经病学   8篇
特种医学   38篇
外科学   31篇
综合类   3篇
预防医学   19篇
眼科学   1篇
药学   14篇
肿瘤学   15篇
  2022年   2篇
  2018年   5篇
  2017年   8篇
  2016年   3篇
  2015年   3篇
  2014年   6篇
  2013年   12篇
  2012年   5篇
  2011年   7篇
  2010年   13篇
  2009年   5篇
  2008年   11篇
  2007年   10篇
  2006年   10篇
  2005年   17篇
  2004年   5篇
  2003年   3篇
  2002年   2篇
  2001年   2篇
  2000年   1篇
  1999年   7篇
  1998年   12篇
  1997年   12篇
  1996年   19篇
  1995年   15篇
  1994年   14篇
  1993年   15篇
  1992年   3篇
  1990年   3篇
  1989年   8篇
  1988年   9篇
  1987年   9篇
  1986年   7篇
  1985年   10篇
  1984年   5篇
  1983年   5篇
  1981年   4篇
  1980年   6篇
  1979年   2篇
  1978年   3篇
  1977年   4篇
  1976年   4篇
  1975年   2篇
  1966年   1篇
  1959年   2篇
  1954年   1篇
  1949年   1篇
  1931年   1篇
  1919年   1篇
  1889年   1篇
排序方式: 共有318条查询结果,搜索用时 15 毫秒
71.
We retrospectively reviewed cases of 19 of 35 patients who underwent operative treatment for type II fractures of the distal clavicle over 7 years. The average age was 21.5 years. There were 15 males. Ten of the fractures occurred in vehicular accidents and eight in sports. Ten of the fractures were comminuted. All fractures were closed. Thirteen patients were treated with transacromial Kirschner wires and six by other methods. There were 10 satisfactory and nine unsatisfactory results. All six nonunions and five of the six deep infections occurred in those treated with transacromial wires. Our results indicate that transacromial wire fixation may not be the treatment of choice for this uncommon fracture.  相似文献   
72.
73.
74.
Background Transposition of great arteries (TGA) with Single Coronary artery is one of the high risk groups for Arterial Switch Operation (ASO). To eliminate this risk, we have innovated a new technique of ASO with insitu coronary re-allocation. We present our experience with this new technique. Methods From September 1998 to October 2005, ten consecutive cases of TGA with single coronary artery were operated employing this new technique. Their age ranged from 8 days to 9 months; their weight ranged from 2.6 to 5.8 Kgs. ASO was done by transecting the great arteries just above the commissures. For coronary re-allocation, hockey stick shaped incisions were made in the facing sinuses of the proximal aorta and the pulmonary artery. These flaps were sutured in such a way that the coronary ostium was committed to the neo-aorta. Results There was no in-hospital mortality. The follow-up ranged from 4 months to 7 years. All patients had follow-up echocardiogram at regular intervals, which showed no significant right or left ventricular outflow obstruction, no regional wall motion abnormalities and no, neo-aortic or neo-pulmonary regurgitation. Conclusion This new coronary re-allocation technique avoids problems related to coronary translocation such as traction and kinking. It spares the need for dissection of proximal coronary artery and its branches, and thereby eliminates the risk of development of fibrosis and stenosis. The same technique can be used regardless of the sinus of origin of the coronary artery. It is a reliable and reproducible technique. The early results were excellent.  相似文献   
75.
OBJECTIVE: Fetal measurement of transverse cerebellar diameter (TCD) has been shown to correlate well with gestational age (GA), even in the presence of growth retardation. The aim of this study was to define the normal range of TCD in preterm neonates in an Australian population between 23 and 32 weeks GA. METHODOLOGY: Infants admitted to the Royal Women's Hospital, Melbourne, having routine cranial ultrasound scans (< 1500 g and/or of gestational age 相似文献   
76.
Posterior atlantooccipital subluxation in Down syndrome   总被引:3,自引:0,他引:3  
Three Down syndrome patients with posterior atlantooccipital (AO) subluxation are described. All are asymptomatic. The subluxation becomes manifest during active extension of the neck and reduces in flexion. Methods of assessing posterior AO subluxation are discussed. The abnormality is attributed to ligamentous laxity in patients with Down syndrome.  相似文献   
77.
Recombinant canine granulocyte-macrophage colony-stimulating factor (rcGM-CSF) was studied in normal dogs and in dogs receiving otherwise lethal total body irradiation (TBI) without marrow transplant. Five normal dogs receiving 25 micrograms/kg of rcGM-CSF by subcutaneous (SC) injection twice daily (BID) for 14 days showed increases in peripheral blood neutrophil counts of three to five times the baseline. Platelet counts decreased during administration of rcGM-CSF to a mean nadir of 52,800. Ten dogs received 400 cGy TBI at 10 cGy/min from two opposing 60Co sources and no marrow graft. Within 2 hours of TBI, rcGM-CSF was begun at a dose of 50 micrograms/kg SC BID for 5 doses and then continued at 25 micrograms/kg SC BID for 21 days. Only 1 of the 10 dogs receiving rcGM-CSF survived with complete and sustained recovery of hematopoiesis. One of 13 historical control dogs survived after 400 cGy with no hematopoietic growth factor or marrow infusion. Results with rcGM-CSF were compared with previous and concurrent data with G-CSF studied in the same model. Of 10 dogs receiving G-CSF, 8 survived with complete and sustained hematopoietic recovery, a significantly better survival than that seen with rcGM-CSF (P = .006). Neutrophil counts were sustained at higher levels after TBI for the first 18 days in the G-CSF group (P < .016) and the neutrophil nadirs were higher. No differences in neutrophil nadirs were noted between the rcGM-CSF and control groups. Dogs treated with rcGM-CSF experienced a more rapid decline of platelet counts than G-CSF-treated or control dogs over the first 18 days (P < .001). The nadir of the platelet count was higher in the control group than in either the G-CSF or rcGM-CSF group and no significant difference was observed between the G-CSF and rcGM-CSF groups. After otherwise lethal TBI (400 cGy) in dogs, rcGM-CSF was not effective in promoting hematopoietic recovery or improving survival.  相似文献   
78.
79.
The effects of daily administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) to eight normal volunteers donating granulocytes for neutropenic relatives undergoing marrow transplantation were studied. Granulocyte donors consisted of seven marrow donors (5 syngeneic, 2 HLA identical) and one haploidentical son who had not donated marrow. All donors were administered daily rhG-CSF at a mean dose of 5 micrograms/kg/d (range 3.5 to 6.0) for a mean of 11.75 days (range 9 to 14 days), and granulocytes were collected a mean of 7.6 times (range 4 to 12). RhG-CSF was well tolerated and only minor side effects were observed. All donors became anemic from marrow donation and the removal of red blood cells during the collection procedures. Red blood cell transfusions were not given. All donors had a decrease in platelet counts and the magnitude of the decrement appeared to be greater than in historical donors. This was due in part to increased removal of platelets with the collection product, but a direct effect of rhG-CSF on platelet production cannot be excluded. The mean precollection granulocyte level was 29.6 x 10(9)/L (range 11.8 to 79.8), which was a 10-fold increase over baseline. The mean number of granulocytes collected was 41.6 x 10(9) (range 1.3 to 144.1), which was a six-fold increase over historical donors not receiving rhG-CSF. The mean granulocyte level 24 hours after transfusion into neutropenic recipients was 0.95 x 10(9)/L (median 0.57 and range .06 to 9.47). This study indicates that rhG-CSF is safe to administer to normal individuals, significantly improves the quantity of granulocytes collected, and results in significant circulating levels of granulocytes in neutropenic recipients. Further studies to evaluate rhG- CSF in normal granulocyte donors are warranted.  相似文献   
80.
A deficiency of protein C (PC), antithrombin, or protein S is strongly associated with deep-vein thrombosis in selected patients and their families. However, the strength of the association with venous thrombosis in the general population is unknown. This study was a population-based, patient-control study of 474 consecutive outpatients, aged less than 70 years, with a first, objectively diagnosed, episode of venous thrombosis and without an underlying malignant disease, and 474 healthy controls who matched for age and sex. Relative risks were estimated as matched odds ratios. Based on a single measurement, there were 22 (4.6%) patients with a PC deficiency (PC activity, less than 0.67 U/mL or PC antigen, less than 0.33 U/mL when using coumarins). Among the controls, the frequency was 1.5% (seven subjects). Thus, there is a threefold increase in risk of thrombosis in subjects with PC levels below 0.67 or 0.33 U/mL [matched odds ratio, 3.1; 95% confidence interval (CI), 1.4 to 7.0]. When a PC deficiency was based on two repeated measurements, the relative risk for thrombosis increased to 3.8 (95% CI, 1.3 to 10); when it was based on DNA-confirmation, the relative risk increased further to 6.5 (95% CI, 1.8 to 24). In addition, there was a gradient in thrombosis risk, according to PC levels. The results for antithrombin are similar to those for PC, although less pronounced (relative risk, 2.2; 95% CI, 1.0 to 4.7). We could not find an association between reduced total protein S (relative risk, 0.7; 95% CI, 0.3 to 1.8) or free protein S levels (relative risk, 1.6; 95% CI, 0.6 to 4.0) and thrombosis risk. Although not very frequent, PC and antithrombin deficiency are clearly associated with an increase in thrombosis risk.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号