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   131篇
  免费   7篇
  国内免费   1篇
儿科学   2篇
妇产科学   4篇
基础医学   28篇
口腔科学   1篇
临床医学   6篇
内科学   34篇
皮肤病学   3篇
神经病学   3篇
外科学   4篇
综合类   2篇
一般理论   1篇
预防医学   15篇
眼科学   6篇
药学   26篇
中国医学   2篇
肿瘤学   2篇
  2022年   4篇
  2021年   4篇
  2020年   4篇
  2019年   8篇
  2018年   5篇
  2017年   4篇
  2016年   3篇
  2015年   3篇
  2014年   3篇
  2013年   14篇
  2012年   7篇
  2011年   17篇
  2010年   9篇
  2009年   10篇
  2008年   9篇
  2007年   11篇
  2006年   5篇
  2005年   5篇
  2004年   6篇
  2002年   1篇
  1998年   3篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1979年   1篇
排序方式: 共有139条查询结果,搜索用时 31 毫秒
1.
2.

Background  

The purpose of this study was to characterize total homocysteine (tHcy) levels at birth in preterm and term infants and identify associations with intraventricular hemorrhage (IVH) and other neonatal outcomes such as mortality, sepsis, necrotizing enterocolitis, bronchopulmonary dysplasia, and thrombocytopenia.  相似文献   
3.
4.
Aim: Because of wide variation in clinico‐pathological spectrum of gallbladder disease in children the world over, the data of gallbladder disease from this stone belt of India were analysed. Methods: Children who underwent cholecystectomy over a period of 8 years January 2002–December 2009 were reviewed. Results: Out of 7076 cholecystectomies, 56 (0.79%) were in children. Thirty‐nine (69.6%) children were 11–16 years of age. Thirty‐seven (66.07%) children were girls and nineteen (33.9%) were boys. In 12 (21.4%) children, cholecystitis was acalculus. Five (8.9%) children had associated haemolytic disease and 4 (7.1%) children had congenital anomaly in the form of choledochal cyst. Ultrasound findings were available in 44 cases and showed cholelithiasis in 36 cases. Twenty‐two (39.3%) children had mixed cholelithiasis, 8 (14.2%) pigment cholelithiasis, 10 (17.8%) combined cholelithiasis and 4 (7.1%) patients had small concretions. Microscopically, changes of chronic cholecystitis were seen in 98.2% while 1.7% showed acute on chronic cholecystitis. There was single unusual case of cysticercus in the wall of the gallbladder. Conclusions: The frequency of gallstone disease is 0.79%. Nonhaemolytic type of cholelithiasis is more common than haemolytic type in this region. Presence of cysticercus in the gallbladder wall in one case was an unexpected finding.  相似文献   
5.
This study was designed to evaluate the role of fine‐needle aspiration cytology (FNAC) in diagnosis of skeletal tuberculosis (TB). In this retrospective study, 20 cases were retrieved over a 10‐year period in which a cytologic diagnosis of osseous TB was rendered. The aspirations were performed with a 22‐gauge needle attached on a 20‐ml syringe after taking into consideration the radiological findings. The cytologic findings were subdivided into the following categories—epithelioid cell granulomas with necrosis, epithelioid cell granulomas without necrosis, and necrosis only. These cases were either with or without AFB positivity. The smears showed epithelioid cell granulomas in 23 cases (85.2%), multinucleate and Langhans' giant cells in 15 cases (55.6%), and inflammatory cells were noted in the background in 15 cases (55.6%). AFB was positive in six cases (22.7%). FNA provides a simple and safe outpatient procedure for the diagnosis of osseous TB and obviates the need of an open biopsy. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
6.
The vitamin K concentration in the circulation and the availability of vitamin K to bone may be affected by factors influencing lipoprotein metabolism, such as apoE genotype. The relationships between markers of vitamin K status, bone mineral content and apoE genotype were studied in healthy older men and women aged 60-83 years, 177 from Shenyang, China, and 132 from Cambridge, UK. Fasting plasma was analysed for vitamin K1, triacylglycerol, total osteocalcin, undercarboxylated osteocalcin (ucOC) and apoE genotype. Hip bone mineral content was measured using dual-energy X-ray absorptiometry. Subjects were grouped according to apoE genotype as E2/3, E3/3 and [E3/4+E4/4]. The mean plasma vitamin K1 concentration of the three genotype groups was significantly higher and the percentage ucOC was lower in the Chinese than in the British subjects (P<0.01). A higher vitamin K1 concentration was found in subjects with [E3/4+E4/4] than those with either E2/3 or E3/3 in Cambridge (32.2 (SE 14.6 ) %, P=0.03; 24.6 (SE 10.7 ) %, P=0.02). Similar trends were observed although were not statistically significant in Shenyang (26.5 (18.9) %, P=0.16; 23.1 (13.0) %, P=0.08). Subjects with [E3/4+E4/4] had a lower percentage ucOC (total osteocalcin adjusted) than did those with either E2/3 or E3/3 in Shenyang (65.1 (27.2) %, P=0.02; 49.6 (19.9) %, P=0.01 respectively) but not in Cambridge. This study demonstrates that a superior vitamin K status is associated with the apoE4 genotype in healthy older individuals from China and the UK.  相似文献   
7.
To explore whether differences in vitamin K nutrition might, at least in part, underlie differences in fracture incidence between Asian and European populations, the vitamin K status of older individuals in Shenyang, China (eighty-six men, ninety-two women) and in Cambridge, UK (sixty-seven men, sixty-seven women) was compared. Dietary information was collected by food questionnaire in Shenyang and food diary in Cambridge and used to estimate the intake and sources of phylloquinone. Fasting blood was analysed for phylloquinone, triacylglycerol, total osteocalcin (tOC) and undercarboxylated osteocalcin (expressed as percentage of tOC; %ucOC). The mean intakes of green leafy vegetables were 127 (SD 90) g/d in Shenyang and 39 (SD 48) g/d in Cambridge. The estimated phylloquinone intakes (geometric means) were 247 (95% CI 226, 270) microg/d in Shenyang and 103 (95% CI 94, 112) microg/d in Cambridge. Plasma phylloquinone concentrations (geometric means) were significantly higher in the Shenyang subjects (2.17 (95% CI 1.95, 2.42) nmol/l) than in the Cambridge subjects (0.69 (95% CI 0.63, 0.76) nmol/l; P<0.001). Plasma phylloquinone concentration was positively related to phylloquinone intake in both the Shenyang (coefficient 0.17 (SE 0.08); P=0.03) and Cambridge subjects (coefficient 0.29 (SE 0.10); P=0.005). tOC concentration and %ucOC (after adjusting for tOC) were significantly lower in the Shenyang than in the Cambridge subjects (tOC 25.2 (SE 4.2)% and %ucOC 68.5 (SE 10.0)% lower respectively; P<0.001). After adjusting for tOC and triacylglycerol, %ucOC was negatively related to plasma phylloquinone concentration in both the Shenyang (coefficient -0.41 (se 0.11); P=0.0003) and Cambridge subjects (coefficient -0.17 (SE 0.07); P=0.02). The present study demonstrates that older individuals in northern China have a better vitamin K status compared with their British counterparts in Cambridge, UK.  相似文献   
8.
9.
Ethnic differences in bone metabolism have been reported and it has been suggested that these may be partly due to prolonged exposure to an elevated plasma parathyroid hormone (PTH) concentration or a decreased sensitivity to PTH. We explored ethnic differences in bone and mineral metabolism by 5 days of oral phosphate (P) loading to stimulate PTH secretion. Healthy older people from UK (B), The Gambia (G) and China (C), 15 individuals from each sex and ethnic group, were studied. Blood and urine samples were collected before and 2 h after P dose on days 1, 4 and 5 and on a control day. The induced changes (%) in PTH and markers of mineral and bone metabolism after 2 h and over 5 days were examined.At baseline, PTH, 1,25(OH)2D and bone turnover markers were higher in Gambian subjects than in British and Chinese subjects (P  0.01).2 h after P loading, ionized calcium (iCa) decreased and PTH and plasma P (P) increased in all groups (P  0.01, n.s. between groups). Urinary P to creatinine ratio (uP/Cr) increased, the increase being greater in Chinese subjects than in British and Gambian subjects on days 4 and 5 (P  0.01). By day 5, fasting iCa was decreased and P increased in British and Gambian (P  0.01) but not in Chinese subjects. Fasting PTH and uP/Cr increased in all groups. There were ethnic differences in changes in bone markers, but the relationship with changes in PTH was comparable between groups.In conclusion, ethnic differences in mineral metabolism in response to 5-day P loading were found. Chinese subjects showed a more rapid renal clearance of P than British and Gambian counterparts and there were differences between the groups in the skeletal response to P loading, but no evidence was found for resistance to the resorbing effects of PTH.  相似文献   
10.
Many sub-unit vaccines are successful in preventing the occurrence of disease, but their use is largely restrained due to low immunogenicity. Novel carrier-based vaccine could serve as a vaccine adjuvant to overcome low immunogenicity of sub-unit vaccines. The use of liposomes as a delivery system for antigen is well recognized but they are unstable and release of antigen from them cannot be controlled over a prolonged period of time. To overcome the limitation of liposomes, this study has developed gel core liposomes in which a core of polymer was incorporated inside the liposomal vesicles, which serve the function of skeleton and provide mechanical strength to vesicles. In the present investigation BSA-loaded gel core liposomes were prepared by reverse phase evaporation method and characterized for vesicles size, shape, entrapment efficiency, in vitro release and stability studies. The in vivo studies to evaluate antigen presenting potential of the gel-core liposomes was performed in Balb/c mice by measuring the immune response elicited by intramuscular administration of BSA-loaded gel core liposomes and compared with intramuscularly administered BSA-loaded conventional liposomes, alum adsorbed BSA and plain antigen. Results indicate that intramuscular immunization with gel core liposomes induces efficient systemic antibody responses against BSA as compared to other formulations. The gel core liposomal formulation provides good entrapment efficiency, enhanced in vitro stability, prolonged antigen release and effective immunoadjuvant property, justifying its potential for improved vaccine delivery.  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