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   220篇
  免费   5篇
儿科学   5篇
基础医学   18篇
口腔科学   3篇
临床医学   3篇
内科学   24篇
皮肤病学   1篇
神经病学   24篇
特种医学   50篇
外科学   20篇
综合类   49篇
预防医学   5篇
眼科学   7篇
药学   5篇
肿瘤学   11篇
  2023年   2篇
  2022年   1篇
  2021年   3篇
  2019年   3篇
  2016年   2篇
  2015年   1篇
  2014年   2篇
  2012年   9篇
  2011年   8篇
  2010年   12篇
  2009年   10篇
  2008年   3篇
  2007年   6篇
  2006年   6篇
  2005年   5篇
  2004年   6篇
  2003年   4篇
  2002年   7篇
  2001年   10篇
  2000年   7篇
  1999年   8篇
  1998年   7篇
  1997年   8篇
  1996年   8篇
  1995年   8篇
  1994年   10篇
  1993年   4篇
  1991年   3篇
  1990年   1篇
  1989年   6篇
  1988年   5篇
  1987年   3篇
  1986年   6篇
  1985年   4篇
  1984年   3篇
  1983年   7篇
  1982年   10篇
  1981年   2篇
  1980年   5篇
  1979年   4篇
  1978年   2篇
  1977年   2篇
  1974年   1篇
  1972年   1篇
排序方式: 共有225条查询结果,搜索用时 31 毫秒
21.

Background

Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative.

Methods

Sixty consecutive cases requiring adenoidectomy were randomized into two groups of thirty each. Group A underwent conventional adenoidectomy using the curettage method and Group B underwent endoscopic assisted micro-debrider adenoidectomy. The parameters studied were intra-operative time, intra-operative bleeding and completeness of resection, collateral damage, post operative pain and recovery time.

Result

Sixty cases of adenoidectomy were done using conventional surgery and powered endoscopic adenoidectomy in the study period from Aug 04 to Dec 05. The time taken in Group A (conventional surgery) varied from 22–39 minutes (95% Confidence Interval (CI) −27.7 – 30.9)and in Group B (powered endoscopic surgery) from 27–55 minutes(95% CI 36.6 – 41.9) (p<0.05). The average blood loss in Group A was 21 ml (range 10–50) as compared to 31.67 ml (range 10-60) in Group B (p<0.05). The resection was invariably complete in Group B whereas seven(23%) cases had more than 50% residual adenoid tissue in Group A. Three cases in group A had collateral damage whereas in Group B, there were no added injuries. Post operative pain was studied only in cases undergoing adenoidectomy alone. Group A (n=8) demonstrated a pain score of 1.64–2.63–3.63 (95% CI) whereas Group B (n=11) demonstrated a pain score of 1.19–2.13–3.06 (95% CI). This difference was not statistically significant. In group A, the mean recovery period was 3.5 days and 2.93 days in Group B(p<0.05).

Conclusion

Endoscopic powered adenoidectomy was found to be a safe and effective tool for adenoidectomy. The study parameters where endoscopic powered adenoidectomy fared better were completeness of resection, accurate resection under vision, lesser collateral damage and faster recovery time. On the other hand, conventional adenoidectomy scored in matter of lesser operative time and intra-operative bleeding.Key Words: Adenoidectomy, Powered adenoidectomy, Endoscopic adenoidectomy  相似文献   
22.

Background

A significant number of soldiers suffer serious injuries or die in the process of demining and a protective device is necessary in such operations.

Methods

All the patients involved in demining operations using the foot protection devices in last one year were analysed.

Results

We received 35 patients, of which only five had limb injuries and 30 had eye injuries. Of the five, three had closed calcaneal fractures and two contusion of foot. No fatality, amputation or compound fracture occured.

Conclusion

Early results after the use of this device during demining operations are encouraging.Key Words: Mine blast injury, Demining, Spider boot  相似文献   
23.
To understand the role of carotid chemoreceptor activity in the ventilatory responses to sustained hypoxia (30 min) the following measurements were made in cats anesthetized with alpha-chloralose: (1) carotid chemoreceptor and ventilatory responses to isocapnic hypoxia and to hypercapnia during hyperoxia; (2) carotid chemoreceptor responses to isocapnic hypoxia after dopamine receptor blockade; and (3) ventilatory responses to hypoxia after bilateral section of carotid sinus nerves (CSN). Transition to hypoxia (PaO2 approximately equal to 52 Torr) from hyperoxia gradually increased carotid chemoreceptor activity by ten fold and ventilation by two fold without any detectable overshoot. Termination of isocapnic hypoxia with hyperoxia (PaO2 greater than 300 Torr) at 30 min promptly restored the carotid chemoreceptor activity to prehypoxic level. Ventilation also decreased promptly, but remained above the control value. Induction of hypercapnia (from 31.8 Torr to 43.9 Torr) during hyperoxia was followed by a prompt increase in the chemoreceptor activity by four fold which subsequently diminished, and by a gradual four fold increase in ventilation. Termination of hypercapnia after 30 min was followed by a prompt return of chemoreceptor activity and by a slow return of ventilation to near control levels. Dopamine receptor blockade increased carotid chemoreceptor responsiveness to acute hypoxia but did not alter the response pattern during sustained hypoxia. After bilateral CSN section, ventilation decreased during maintained hypoxia. Thus, a stimulatory peripheral and inhibitory central effects of hypoxia could produce a biphasic ventilatory response to short-term hypoxia in the anesthetized cat with intact CSN but did not manifest it. The results suggest that the chemosensory input not only promptly stimulates ventilation but also prevents the subsequent depressant effect of hypoxia on the brain-stem respiratory mechanisms and hence presumably a biphasic ventilatory response in the anesthetized cat.  相似文献   
24.
The Kheda project experience has shown that bio-environmentalcontrol of malaria is feasible, cost effective and ecologicallysound. It clearly brings out the need to consider health issuesat the planning stage of all developments. Bio-environmentalcontrol of malaria is suggested as the first line of attackfor the control of mosquitoes, malaria and other mosquito-bornediseases. Insecticides may be reserved for short-term use. Thiswill enable judicious and selective use of insecticides in solelyepidemic situations. The growing problem of resistance to insecticidesin mosquitoes as well as environmental pollution, can then besolved on a long term basis.  相似文献   
25.
研究背景和目的   在急诊救治的过程中最重要的就是快速建立静脉通道,以补充体液、给药以及输血等.但是,由于皮下结构(如血管深度、脂肪组织、皮肤色素、血管内血容量)的复杂性,往往阻碍了肉眼下静脉穿刺过程的实施.血管超声可以辅助寻找相对较粗的静脉,但是此设备和技术的要求较高,影响了其在临床的广泛应用;可见光透射法所得结果不甚可靠,且容易造成灼伤.红外成像时由于其穿透深度较可见光深,而且血液对红外光能量的吸收明显高于脂肪和黑色素等血管周围组织,因而可以得到对比度清晰的图像.……  相似文献   
26.
Abstract. The susceptibility of cultured rat kidney parenchymal components to natural killer (NK) cell and lymphokine-activated killer (LAK) cell-mediated lysis in a 4-h in vitro 51chromium assay was investigated. Large granular lymphocytes (LGL) in the spleen and in the kidney allograft were able to lyse YAC cells during rejection, but they did not damage target endothelial, glomerular mesangial, glomerular epithelial, or tubular cells in resting state. Stimulation of the target cells with gamma-interferon - known to induce MHC (class II) antigens on the target cell surface - did not make the target cells susceptible to NK-mediated lysis. LAK cells generated by a 3-day incubation with interleukin-2 (IL-2) effectively lysed both YAC and P815 target cell lines. LAK cells were also slightly cytotoxic to all tested parenchymal target components in resting state. Gamma-interferon treatment of the cultured parenchymal cells prior to the chromium release assay, however, reduced LAK-mediated parenchymal cell cytotoxicity to nearly nondetectable levels. Obviously, many lymphokines, including IL-2 and gamma-interferon, are produced during rejection at the site of inflammation. This might induce the generation of LAK cells in situ as the lymphokines induce the production of MHC antigens in the graft. We interpret these findings as indicating that regardless of the generation of LAK, the protective effect of gamma-interferon neutralizes the LAK effect, and we suggest that neither LGL nor LAK cells play any essential role in rat kidney allograft rejection.  相似文献   
27.
Preoperative needle localization in the breast: utility of local anesthesia   总被引:1,自引:0,他引:1  
  相似文献   
28.
Previously we reported that activities of certain chemoreflex sensitive cervical preganglionic sympathetic nerves (PSN) were augmented by carotid chemoreceptor stimulation independently of phrenic nerve (PN) activity in the cat. To test the hypothesis that the PSN carotid chemoreflex could have been mediated by the expiratory neuron activity, we studied the relationship between PSN, internal intercostal expiratory nerve (IICEN) and PN activities in vagotomized, anesthetized, paralysed and artificially ventilated cats. We made the following observations. (1) Hypoxia often inhibited IICEN activity while the PN and PSN activities were stimulated. (2) during normoxia, cyanide strongly stimulated PN and PSN discharges but only moderately IICEN discharges. (3) Hyperventilation hypocapnia suppressed or eliminated PSN and PN rhythms and activities, but made some IICEN fibers fire continuously. (4) During hypocapnic apnea, cyanide stimulated PSN activity before PN and IICEN activities, although some PSN fibers were stimulated simultaneously with PN fibers. Accordingly we conclude that IICEN activity does not significantly influence chemoreflex stimulation of PSN activity and that a direct chemoreflex stimulation of IICEN is minimal in the cat. Thus, the chemoreflex PSN response is in part independent of respiratory chemoreflex pathways.  相似文献   
29.
In a prospective survey carried out over 12 months 447 children aged under 2 years were admitted to the Manchester Regional Infectious Diseases Unit for treatment of gastroenteritis. Comparison of the children with those in a survey 15 years previously in the same unit showed that the illness was milder than in the earlier series, with no deaths and with lower incidences of hypernatraemia (1%), uraemia (8%), and dehydration (14%). These improved findings occurred despite several deficiencies of care in the prehospital phase of the illness, particularly poor compliance with the widely recommended guidelines for fluid and dietary management in infantile gastroenteritis.  相似文献   
30.
CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell development. Here we explore the capacity of TCR-CD3 signaling complexes expressed on delta degrees thymocytes to mediate the following functional outcomes in response to antibody cross-linking: (i) the transition from the CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We provide evidence that CD3deltaepsilon complexes are dispensable for mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8- thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or consecutive stimuli to elicit functional responses. Depending on the nature of the secondary stimulus, delta degrees thymocytes can be induced to undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken together these results indicate that the signaling capacity of the TCR-CD3 complex is noticeably altered in the absence of CD3delta. The essential role of CD3delta at the CD4+CD8+ stage of development correlates with the onset of TCRalpha rearrangement, consistent with a critical structural and/or functional relationship between CD3delta and TCRalpha.   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