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   642篇
  免费   43篇
  国内免费   3篇
耳鼻咽喉   13篇
儿科学   27篇
妇产科学   8篇
基础医学   77篇
口腔科学   10篇
临床医学   63篇
内科学   157篇
皮肤病学   16篇
神经病学   23篇
特种医学   6篇
外科学   79篇
综合类   14篇
预防医学   53篇
眼科学   31篇
药学   51篇
中国医学   6篇
肿瘤学   54篇
  2024年   1篇
  2023年   11篇
  2022年   26篇
  2021年   44篇
  2020年   21篇
  2019年   21篇
  2018年   45篇
  2017年   17篇
  2016年   14篇
  2015年   26篇
  2014年   26篇
  2013年   35篇
  2012年   49篇
  2011年   47篇
  2010年   26篇
  2009年   22篇
  2008年   51篇
  2007年   41篇
  2006年   31篇
  2005年   26篇
  2004年   21篇
  2003年   22篇
  2002年   16篇
  2001年   3篇
  2000年   2篇
  1999年   6篇
  1998年   2篇
  1997年   2篇
  1996年   2篇
  1995年   3篇
  1994年   3篇
  1992年   2篇
  1991年   3篇
  1989年   1篇
  1985年   4篇
  1984年   2篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
  1978年   1篇
  1970年   1篇
  1968年   1篇
  1966年   1篇
  1965年   1篇
  1964年   1篇
  1963年   1篇
  1962年   1篇
  1961年   1篇
  1943年   1篇
排序方式: 共有688条查询结果,搜索用时 15 毫秒
61.
62.
63.
64.
65.

Purpose

Cholinergic and nitrergic neurons form 2 main subpopulations of the myenteric neurons, and they have been the targets of detailed morphological investigations in bowel motility disorders. However, little is known regarding the colocalization of neurotransmitters within the same enteric neurons. The aim of this study was to determine the histochemical colocalization of cholinergic and nitrergic neurons in the porcine distal large bowel myenteric plexus from fetal to adulthood.

Methods

Distal large bowel specimens were taken from 6 randomly selected age groups (3 animals in each group) from midway of gestation to adulthood. The myenteric plexus was exposed using whole-mount technique. After nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) staining, cells per ganglion were counted. Then the specimens were stained with acetylcholinesterase (AChE), and the cells that were stained with individual enzymes and with both enzymes were counted.

Results

Colocalization of AChE and NADPH-d was seen in all age groups, and it was highest during the mid part of gestation (30%) and decreased steadily thereafter into adulthood (8%). The individual number of NADPH-d- and AChE-positive neurons per ganglion remained constant till 4 weeks of age and significantly increased thereafter into adulthood.

Conclusion

The use of double-labeling histochemical technique shows for the first time the colocalization of cholinergic and nitrergic activity in a large population of enteric neurons in the late fetal and newborn period. Age-related loss of cholinergic and nitrergic colocalization in the myenteric plexus is most likely a maturational process.  相似文献   
66.
67.
The study was undertaken to assess the respiratory and sympathetic cardiovascular functions in obese and non obese school children of 12-16 years age group, randomly selected from two schools of Rajpura (Punjab), representing mixed socioeconomic group of Punjabi ethnicity and categorized as obese or controls as per standard criteria for Body Mass Index (BMI). Dynamic lung function tests and pressor response to cold (Cold pressor test) and isometric exercise (Handgrip dynamometer test) were carried out. Statistical analysis comprised students' t-test, at 95% confidence level and simple linear regression analysis. The results indicated significantly higher baseline diastolic blood pressure (DBP) (P < 0.004) in obese children correlating positively with BMI (r = 0.57). Significantly increased DBP response to applied cold stimulus (response/range, P < 0.02 and maximal value, P < 0.001) and borderline response to isometric exercise (P < 0.002) in obese children indicated autonomic instability. The dynamic lung functions were significantly decreased (P < 0.04) in obese subjects and correlated negatively with BMI. Personal data forms of obese children revealed less physical activity and excessive intake of junk foods. Thus it is concluded that obese children have derangement of sympathetic cardiovascular functions and reduced pulmonary functions.  相似文献   
68.
Widespread use of Haemophilus influenzae type b (Hib) conjugated vaccine in industrialized countries has resulted in a dramatic decline in the incidence of invasive Hib diseases, but the vaccine's cost has prevented its inclusion in basic immunization programs in developing countries. To overcome this problem, combination with diphtheria-tetanus-pertussis (DTP) vaccine or reduction in the dose of Hib vaccine has been proposed. To evaluate the immunogenicity and adverse reactions from lower doses of Hib-polyribosylphosphate (PRP) conjugated with tetanus toxoid (PRP-T), a double-blind study was conducted in Jakarta, Indonesia, and its suburbs. A total of 1048 infants 6 weeks to 6 months of age received three doses of DTP vaccine combined with the usual 10 microg dose or with a reduced dose of 5, 2.5 or 1.25 microg of PRP-T at two-monthly intervals. Antibodies were measured prior to the first dose and 4-6 weeks following the third dose. Adverse reactions were similar among all four groups. The only significant difference was a higher rate of irritability (p<0.02) and of temperature elevation >38 degrees C (p<0.009) after doses 1 and 2 in the lowest dose group (1.25 microg PRP-T) compared to the other groups. All participants tested had a 4-fold increase in antibodies against all DTP antigens. In addition, after a fourth booster dose of Hib, 99.6% of infants produced >or=0.15 microg/ml of antibody to Hib-PRP, and 96.4% showed levels >or=1.0 microg/ml after primary immunization, level that correlate with short- and long-term immunity, respectively. Antibody titers to the PRP antigen showed no significant differences among dosage groups with the exception of the 5.0 microg group, which had a significantly higher GMC than the 1.25 microg group (p<0.012). This study demonstrates that primary vaccination with half, one-fourth, or one-eighth of the usual dose of PRP-T, combined with DTP vaccine, produces protective immune responses, and has side effects that are comparable to DTP vaccination alone. In these lower dosages, PRP-T conjugate vaccine can lower vaccine costs to a level that is affordable for infant immunization programs in developing countries.  相似文献   
69.
Background: Cancer remains a significant public health problem in Indonesia and worldwide. Yogyakarta Province has the largest number of cancer cases in Indonesia. Maps of the distribution of cancer cases are useful tools for stratification of cancer risk and for selective prevention strategies. The aim of this study was to determine the spatial distribution of cancer cases in Yogyakarta Province. Methods: Cancer patient data registered by the Yogyakarta Provincial Health Office during 2019-2020 were analysed in this study (n=9,933). To evaluate cancer pattern distributions, ArcGIS 10.2 and Excel 2016 software were used. Results: The mean participant age (± standard deviation) was 55.08 ± 15.46 years, and 79.40% were female. Breast and cervical cancer were the most frequently diagnosed, and the majority of patients were located in Sleman district. The incidence of all cancer types varied by county-level. The majority of cancer patients lived below the poverty line. Cancer screening rates were low, and screening was limited to breast and cervical cancer. Conclusion: Various types of cancers were identified in Yogyakarta, Indonesia; of them, breast and cervical cancer predominated. Most of the cancer patients were from Sleman district and economically poor areas. Geospatial techniques are useful for identifying environmental factors related to cancer and improving cancer control strategies and resource allocation.  相似文献   
70.
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