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   237篇
  免费   16篇
耳鼻咽喉   18篇
儿科学   6篇
妇产科学   9篇
基础医学   16篇
口腔科学   9篇
临床医学   19篇
内科学   41篇
皮肤病学   1篇
神经病学   8篇
特种医学   7篇
外科学   54篇
综合类   13篇
预防医学   18篇
眼科学   10篇
药学   17篇
中国医学   1篇
肿瘤学   6篇
  2023年   3篇
  2022年   4篇
  2021年   4篇
  2020年   10篇
  2019年   9篇
  2018年   17篇
  2017年   8篇
  2016年   10篇
  2015年   10篇
  2014年   9篇
  2013年   10篇
  2012年   16篇
  2011年   15篇
  2010年   9篇
  2009年   1篇
  2008年   14篇
  2007年   13篇
  2006年   13篇
  2005年   26篇
  2004年   24篇
  2003年   11篇
  2002年   8篇
  2001年   1篇
  1999年   1篇
  1998年   1篇
  1996年   1篇
  1993年   1篇
  1989年   2篇
  1988年   2篇
排序方式: 共有253条查询结果,搜索用时 0 毫秒
91.
92.
93.
94.
95.
Maxillofacial trauma is the main cause of emergency admittance to dental clinics. Mental retardation and epileptic status are important factors in an increase in the risk of dental injuries. Tooth avulsion, which is the total displacement of a tooth out of its socket, is an infrequently observed entity. Maxillary central incisors are the most commonly affected teeth. The case of a patient with severe dental injury resulting from an epileptic attack is presented. He had several teeth avulsed and displacement of a tooth into the soft tissue of the chin.  相似文献   
96.
OBJECTIVE: To compare nasal mucociliary clearance (NMC) functions in coal workers with pneumoconiosis, coal workers without pneumoconiosis and healthy controls by using technetium-99m-labeled macroaggregated albumin rhinoscintigraphy. METHODS: Sixty-five of the 86 coal workers were clinically documented as suffering from coal workers' pneumoconiosis (CWP group). CWP workers were divided into two groups according to smoking status: 44 smokers (CWP-S) and 21 nonsmokers (CWP-NS). Twenty-one workers without pneumoconiosis (NCWP group) were similarly divided into two groups: 12 smokers (NCWP-S) and 9 nonsmokers (NCWP-NS). Thirty-three healthy male volunteers were selected for the control group [15 smokers (control-S), 18 nonsmokers (control-NS)]. The half-time (t1/2) value for the clearance of the radiopharmaceutical was calculated for each patient. RESULTS: Mean t1/2 values for CWP-S, CWP-NS, NCWP-S, NCWP-NS, control-S and control-NS were 25.10 +/- 7.75, 10.97 +/- 3.24, 14.68 +/- 4.98, 9.17 +/- 3.71, 19.15 +/- 5.04 and 15.08 +/- 5.11, respectively (p < 0.001, Kruskal-Wallis variance analysis). Further, mean t1/2 values of smokers versus nonsmokers in CWP, NCWP and control groups were compared, and it was found that although smoking prolonged nasal transport time in all three groups, the difference was significant only in the CWP group (p < 0.001, p < 0.023 and p < 0.027, respectively, Bonferroni-adjusted Mann-Whitney test). CONCLUSION: Our findings demonstrated a synergistic detrimental effect of smoking with coal dust exposure on nasal transport time.  相似文献   
97.
OBJECTIVE: A prospective study was carried out to find the exact site of obstruction in sleep model and to quantitatively evaluate the effect of Jaw-thrust maneuver (JTM) in opening the obstructed airway using flexible fiberoptic endoscope. METHODS: Twenty-eight ASA physical status I or II patients with snoring symptom undergoing elective surgery were included. The patients were held in supine position without hyperextension of the neck. Having induced anesthesia, the base of the tongue and laryngeal inlet and/or epiglottis were visualized using endoscope. The patients' epiglottides were classified as leaf-shaped, curved (concaved or omega-shaped) and floppy types. We graded the airway opening at the level of epiglottis into six grades and obstruction at the tongue base level into four grades. The grades during inspiration (GrIns), expiration (GrExp) and after JTM (GrJTM) were recorded and compared with Pearson chi-square test. RESULTS: The strictly curved (Omega-shaped or concaved) epiglottis supplied a salvage pathway for airflow that resisted collapsing with the posterior movement of the tongue base in 2 patients. When we compared GrIns with GrExp for epiglottis the difference was statistically significant (chi(2) = 0.001), but the difference for tongue base was not (chi(2) = 0.152). After JTM, GrJTM for both epiglottis and tongue base were significantly better than GrIns and GrExp (chi(2) < 0.001). CONCLUSION: Tongue base was the principal site of obstruction although during the respiratory cycle the position of epiglottis changed prominently and increased the obstruction in inspiration. JTM alone significantly relieved the obstruction at the tongue base and epiglottis levels and increased the retroglossal airway.  相似文献   
98.
BACKGROUND: The aim of this study was to evaluate the effects of lateral osteotomy of septorhinoplasty on nasolacrimal duct functions by dacryoscintigraphy. METHODS: The study group comprised 60 nasolacrimal systems of 30 consecutive patients who underwent septorhinoplasty. Dacryoscintigraphy images were taken in the preoperative period and postoperative 1st week and 3rd month. After Tc-99m pertechnetate instillation, dynamic images were obtained every 15 seconds. For cases of normal drainage, the study was terminated after 10 minutes but when obstruction was suspected, external ocular massage and rapid nasal inspiration were applied and the test was extended for an additional 10 minutes. Systems were classified either as passage without massage (normal nasolacrimal test), passage with massage (physiological obstruction), or presac or postsac obstruction (partial or complete obstruction) according to test results. Transit time was determined for cases with normal test or physiological obstruction. RESULTS: In the preoperative period eight systems (two presac and six postsac) had obstruction. There were a total of 11 (18.3%) additional systems with obstruction (4 presac and 7 postsac) in the 1st postoperative week and patient symptoms were not in complete agreement with the test results in this period. By the 3rd month, nine systems (three presac and six post sac) had obstruction. Transit time was prolonged in both the postoperative 1st week and the postoperative 3rd month tests compared with the preoperative tests (p = 0.000 and p = 0.023, respectively). CONCLUSION: We did not encounter any permanent obstructions after lateral osteotomy of rhinoplasty. Temporary obstructions in the 1st postoperative week improved to normal preoperative status by the postoperative 3rd month.  相似文献   
99.
AIM: To compare echocardiographic findings of infants of diabetic mothers (IDMs), macrosomic infants of nondiabetic mothers and healthy full term appropriate-for-gestational-age (AGA) infants. METHODS: Included in this study were 83 infants, admitted to our Neonatology Unit. Thirty-three IDMs, including both macrosomic and nonmacrosomic, comprised Group A, 25 macrosomic infants of nondiabetic mothers comprised group B, and 25 healthy full term AGA infants comprised group C. Echocardiographic measurements were performed in the first three days after birth and compared by using one-way ANOVA, Post Hoc Tukey HSD and Student's t tests. RESULTS: The left ventricular end-systolic/left ventricular end-diastolic diameter ratio of group A was significantly smaller than that of group C (P<0.05). The interventricular septum/posterior wall thickness ratios of groups A and B were greater than those of group C (P<0.05). The left ventricular mass index of group A was greater than those of groups B and C (P<0.05). The shortening fraction and ejection fraction of group A were increased in comparison to group C (P<0.05). When comparing the values of echocardiographic measurements of macrosomic IDMs (n=9) with nonmacrosomic ones (n=24), and infants of pregestational diabetic mothers (n=11) with those of gestational diabetes mothers (n=22), no statistical difference was found. CONCLUSION: The present study suggests that underlying mechanisms common to both macrosomic infants of nondiabetic mothers and IDMs lead to less cardiac alterations in the macrosomic infants of nondiabetic mothers than in IDMs.  相似文献   
100.
BACKGROUND: Donated platelets for clinical use currently have a shelf life of 5 days as the result of possible bacterial contamination and loss of hemostatic function. Platelet releasates contain multiple growth factors that have been shown to accelerate wound healing. We sought to demonstrate that although expired platelets can no longer sustain hemostasis, they serve a longer term role as a reservoir of growth factors that could be harnessed in wound healing applications. MATERIALS AND METHODS: Liquid preserved human platelets were activated from 1 to 21 days after collection using zeolite and were then analyzed for their ability to stimulate human fibroblast proliferation, which is an in vitro serogate of growth factor activity and wound healing potential. Total protein content, the concentration of platelet-derived growth factor (PDGF) and transforming growth factor-beta were also measured. RESULTS: Activated liquid preserved platelet releasates significantly stimulated fibroblast proliferation. Twenty-one-day-old platelets were as stimulatory as 2-day-old platelets. Total protein concentration, PDGF, and transforming growth factor-beta concentrations remained constant throughout the 21-day course. Western blot analysis using an antibody against human PDGF revealed minimal protein degradation over time. CONCLUSIONS: These data demonstrate that although the role of platelets as hemostatic agents degrades rapidly with time, platelets' ability to serve as a reservoir for growth factors remains intact for at least 3 weeks. These growth factors could be collected, stored, and used as a topical agent to promote healing of chronic and recalcitrant wounds.  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