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   190篇
  免费   4篇
  国内免费   4篇
儿科学   3篇
妇产科学   3篇
基础医学   20篇
口腔科学   2篇
临床医学   20篇
内科学   70篇
皮肤病学   3篇
神经病学   10篇
外科学   19篇
综合类   6篇
预防医学   9篇
眼科学   2篇
药学   26篇
中国医学   1篇
肿瘤学   4篇
  2022年   3篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   2篇
  2016年   2篇
  2015年   1篇
  2014年   3篇
  2013年   3篇
  2012年   4篇
  2011年   1篇
  2010年   14篇
  2009年   18篇
  2008年   7篇
  2007年   7篇
  2006年   7篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   1篇
  2001年   4篇
  2000年   6篇
  1999年   6篇
  1998年   4篇
  1997年   12篇
  1996年   15篇
  1995年   5篇
  1994年   8篇
  1993年   8篇
  1992年   7篇
  1991年   5篇
  1990年   4篇
  1989年   3篇
  1988年   2篇
  1987年   1篇
  1986年   1篇
  1984年   1篇
  1978年   1篇
  1966年   2篇
  1965年   3篇
  1964年   5篇
  1963年   2篇
  1962年   1篇
  1960年   1篇
  1958年   6篇
  1957年   2篇
  1956年   3篇
  1955年   1篇
排序方式: 共有198条查询结果,搜索用时 15 毫秒
11.
CHANG  PENG  LEE  CHEN  CHUA  TSAI  CHI  & HAN 《Clinical and experimental allergy》1999,29(4):488-496
BACKGROUND: Cyn d 1, the major allergen of Bermuda grass pollen, consists of a number of isoforms. OBJECTIVE: To examine the extent of sequence variation of Cyn d 1 isoforms at the molecular level. METHODS: A Bermuda grass pollen lambdaZAP II cDNA expression library was immunoscreened with anti-Cyn d 1 monoclonal antibodies. The reactive clones were isolated, subcloned into Escherichia coli, and sequenced. Some of them were expressed in the yeast Pichia pastoris to obtain recombinant Cyn d 1 proteins. RESULTS: Ten cDNA clones were obtained, all these clones encode the full length of Cyn d 1 protein. Their deduced mature proteins can be grouped into: the long ones with 246 amino acids, and the short ones with 244 amino acids. The last two amino acids (AG) of the long Cyn d 1 are deleted in the short Cyn d 1. The remaining amino acid sequences share more than 98% identity; a total of nine amino acid variations were observed. Two recombinant Cyn d 1 proteins (rCyn d 3-2 and rCyn d 5-4) with three amino acid substitutions showed differential IgE-binding profiles. CONCLUSION: The present study extended our understanding of the primary structure of isoforms of Cyn d 1.  相似文献   
12.
Unipolar Characteristics of CFAEs. Background: The noncontact mapping (NCM) system possesses the merit of global endocardial recording for unipolar and activation mapping. Objective: We aimed to evaluate the unipolar electrogram characteristics and activation pattern over the bipolar complex fractionated atrial electrogram (CFAE) sites during atrial fibrillation (AF). Methods: Twenty patients (age 55 ± 11 years old, 15 males) who underwent NCM and ablation of AF (paroxysmal/persistent = 13/7) were included. Both contact bipolar (32–300 Hz) and NCM virtual unipolar electrograms (0.5–300 Hz) were simultaneously recorded along with the activation pattern (total 223 sites, 11 ± 4 sites/patient). A CFAE was defined as a mean bipolar cycle length of ≤ 120 ms with an intervening isoelectric interval of more than 50 ms (Group 1A, n = 63, rapid repetitive CFAEs) or continuous fractionated activity (Group 1B, n = 59, continuous fractionated CFAEs), measured over a 7.2‐second duration. Group 2 consisted of those with a bipolar cycle length of more than 120 ms (n = 101). Results: The Group 1A CFAE sites exhibited a shorter unipolar electrogram cycle length (129 ± 11 vs 164 ± 20 ms, P < 0.001), and higher percentage of an S‐wave predominant pattern (QS or rS wave, 63 ± 13% vs 35 ± 13%, P < 0.001) than the Group 2 non‐CFAE sites. There was a linear correlation between the bipolar and unipolar cycle lengths (P < 0.001, R = 0.87). Most of the Group 1A CFAEs were located over arrhythmogenic pulmonary vein ostia or nonpulmonary vein ectopy with repetitive activations from those ectopies (62%) or the pivot points of the turning wavefronts (21%), whereas the Group 1B CFAEs exhibited a passive activation (44%) or slow conduction (31%). Conclusions: The bipolar repetitive and continuous fractionated CFAEs represented different activation patterns. The former was associated with an S wave predominant unipolar morphology which may represent an important focus for maintaining AF. (J Cardiovasc Electrophysiol, Vol. 21, pp. 640‐648, June 2010)  相似文献   
13.
14.
Background  Infliximab is used for treatment of Crohn's disease and, following the Active Ulcerative Colitis Trials (ACT) 1 and 2, it has been used as rescue and maintenance therapy in moderate and severe ulcerative colitis (UC).
Aim  To report on English experience with maintenance infliximab in terms of response and colectomy rates and side-effect profile in UC.
Methods  A retrospective audit conducted by using a web-based questionnaire filled in by 12 gastroenterologists from six English centres.
Results  Of the 38 patients receiving induction with infliximab, 28 (73.6%) maintained an ongoing response (8-weekly infusions 5 mg/kg) for a mean duration of 16.8 months (range 4–59), with 21 (55.3%) being in remission. Three of 38 patients (7.9%) who also responded had a secondary loss of response after an average of 10 months (range 8–13); seven of 38 patients (18.4%) showed no response. The colectomy rate was seven of 38 (18.4%, five non-responders and two with secondary loss of response). Adverse effects occurred in five patients (13.2%). Two discontinued infliximab (alopecia, invasive breast cancer). The three less-severe adverse effects were acute and delayed-type hypersensitivity reactions and one persistent otitis media.
Conclusion  Our experience suggests acceptable response rates, colectomy rates and side-effect profile of maintenance therapy with infliximab in moderate and severe UC.  相似文献   
15.
liou s.-r., tsai h.-m. & cheng c.-y. (2013) Journal of Nursing Management  21 , 614–623 Acculturation, collectivist orientation and organisational commitment among Asian nurses working in the US healthcare system Aim To examine the relationships between acculturation, collectivist orientation and organisational commitment among Asian nurses in US hospitals. Background Few studies have explored these three variables together in the same study and examined their statuses and mutual relationship among Asian nurses in Western hospitals. Method The study was a cross-sectional design using snowball sampling. A total of 195 Asian nurses participated. The collectivist orientation scale, organisational commitment questionnaire and acculturation factors were used to collect data. Pearson correlation, anova and regression were used to analyse the data. Results Most participants were female Filipinos with a mean age of 39.92 and a bachelor’s degree and stayed in the USA for 13.35 years. They used and preferred to use both their mother language and English, identified themselves as Oriental or Asian and culturally, viewed themselves as very or mostly Asian. Participants scored high on collectivism and commitment. Collectivism was significantly correlated with commitment but did not mediate acculturation factors and commitment. Conclusion To increase Asian nurses’ commitment, it is important that administrators understand their cultural values and provide them with a cultural competent and sensitive environment. Implications for nursing management Healthcare administrators can increase Asian nurses’ commitment through understanding their needs and attitudes toward their job and organisation.  相似文献   
16.
To assess whether the hepatitis C virus plays an important role in Chinese patients with acute and chronic liver disease, antibodies to HCV (anti-HCV) were measured by enzyme immunoassay in 67 patients with type A and B acute viral hepatitis, 165 patients with non-A, non-B (NANB) hepatitis, 438 patients with chronic hepatitis, 200 patients with postnecrotic liver cirrhosis, 72 patients with alcoholic liver disease, 55 patients with non-alcoholic fatty liver, 24 patients with toxic and drug-induced hepatitis, and 20 patients with other chronic liver diseases. Anti-HCV was not detected in sera from patients with type A and B acute viral hepatitis, toxic and drug-induced hepatitis, primary biliary cirrhosis, Wilson's disease, or lupoid hepatitis. The anti-HCV prevalence was found to be highest in patients with NANB hepatitis (59% in sporadic and 73.2% in transfusion-associated), 16.4% in non-alcoholic fatty liver, 5.6% in alcoholic liver disease, 6.8% in chronic hepatitis, and 16% in postnecrotic liver cirrhosis. In patients with chronic hepatitis, the anti-HCV prevalence was significantly higher in HBsAg-negative (15/34, 44.1%) than in HBsAg-positive cases (15/404, 3.7%; P less than 0.0001). The results indicate that HCV is a major agent of NANB hepatitis and plays an important role in HBsAg-negative chronic liver disease in Taiwan.  相似文献   
17.
Abstract A transjugular liver biopsy was performed on 60 patients. Specimens were successfully obtained from 57 (95%) patients. Specimens obtained from cirrhotic patients were frequently small-sized/fragmented. The wedge hepatic venous pressure and hepatic venous pressure gradient were higher in patients with small-sized/fragmented specimens than those with non-fragmented specimens (16.3 ± 6.4 vs 12.3 ± 4.9 and 10.9 ± 6.2 vs 7.3 ± 3.4 mmHg, P <0.05, respectively). During the same period of time, percutaneous liver biopsies were consecutively performed on 277 patients. The liver specimens by transjugular method were generally smaller (0.63±0.58 vs 1.50±0.86 cm, P <0.001) and more fragmented (63% vs 16%, P <0.01) than those obtained by percutaneous method. Biopsy specimens obtained for diagnosis by the former method were inadequate from 6 (10%) patients and by the latter route were inadequate from 7 (2%) patients. Subcapsular haematoma in one patient was associated with the transjugular liver biopsy. Minor complications occurred in three patients: neck haematoma in two and paroxysmal supraventricular tachycardia during the procedure in one. In comparison, percutaneous liver biopsy was followed by minor complications in 20 patients and major complications in four patients. It is concluded that transjugular liver biopsy is a safe, valuable and alternative procedure to obtain liver specimens, especially in patients who were contraindicated for percutaneous liver biopsy.  相似文献   
18.
Abstract The relationship between the severity of cirrhosis and systemic and hepatic haemodynamic values was evaluated in 193 patients with cirrhosis, most of whom were diagnosed with post-necrotic cirrhosis. It was found that the hepatic venous pressure gradient and cardiac output in Pugh's A patients (13.6 ± 4.8 mmHg and 6.2 ± 1.6 L/min, mean ± s.d.) were significantly lower than in both Pugh's B (16.8 ± 4.3 mmHg and 7.3 ± 2.1 L/min) and Pugh's C (18.8 ± 5.5 mmHg and 7.4 ± 2.3 L/min) patients ( P < 0.01), respectively. In contrast, the systemic vascular resistance in Pugh's A patients (1232 ± 369 dyn/s per cm5) was significantly higher than in both Pugh's B (1016 ± 345 dyn/s per cm5) and Pugh's C (935 ± 234 dyn/s per cm5) patients ( P < 0.01), respectively. Additionally, not only was there a positive correlation found between Pugh's score and cardiac output and hepatic venous pressure gradient, but a negative correlation was found between Pugh's score and systemic vascular resistance. It was also confirmed that the degree of portal hypertension and the hyperdynamic circulation were more severe in patients with ascites than in those without ascites. However, there were no statistically significant differences in hepatic venous pressure gradient among patients with F1, F2 and F3 esophageal varices (15.7 ± 4.0, 17.0 ± 4.8 and 18.0 ± 4.8 mmHg, respectively). It is concluded that in those patients with cirrhosis, the severity of cirrhosis is closely related to the degree of the hyperkinetic circulatory state and portal hypertension.  相似文献   
19.
Propranolol is used clinically as a prophylactic drug to prevent oesophageal variceal bleeding in cirrhotic patients with portal hypertension. Vascular hyporesponsiveness is a common characteristic of the portal hypertensive state. The present study aimed to investigate whether chronic administration of propranolol could improve vascular responsiveness in portal hypertensive rats. Portal hypertension was induced by partial portal vein ligation (PVL). Sham-operated rats served as controls. There were four study groups: PVL–propranolol group (portal hypertensive rats receiving propranolol), PVL–vehicle group (portal hypertensive rats receiving saline), sham–propranolol group (sham-operated rats receiving propranolol) and sham–vehicle group (sham-operated rats receiving saline). Propranolol (30 mg kg?1 day?1) or saline was given for 9 days via gastric gavage starting 1 day before ligation and thereafter. Then, the superior mesenteric artery was removed from each group for contractile study after haemodynamic measurement. In portal hypertensive rats, propranolol significantly alleviated the hyperdynamic state, including portal pressure, cardiac index and total peripheral resistance in the treated group compared with the vehicle group. The maximal contractile responses to KCl and vasopressin in mesenteric artery were significantly greater in the sham–vehicle group than in the PVL–vehicle group. Long-term propranolol treatment enhanced the contractile reactivity of mesenteric artery to KCl and vasopressin in PVL rats, and the contractile profiles were corrected towards those in sham-treated animals. In contrast, propranolol treatment decreased heart rate, mean arterial pressure and cardiac index but did not alter the contractile responsiveness of sham-operated rats These results showed that, in portal vein stenosed rats, long-term treatment with propranolol improved arterial contractile reactivity together with portal pressure reduction. The propranolol effect on vascular reactivity is probably related to haemodynamic improvement, instead of a direct contractile effect on the vasculature.  相似文献   
20.
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