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   1039篇
  免费   45篇
  国内免费   7篇
耳鼻咽喉   20篇
儿科学   71篇
妇产科学   31篇
基础医学   54篇
口腔科学   33篇
临床医学   54篇
内科学   225篇
皮肤病学   20篇
神经病学   64篇
特种医学   15篇
外科学   331篇
综合类   16篇
预防医学   26篇
眼科学   47篇
药学   55篇
  1篇
中国医学   2篇
肿瘤学   26篇
  2024年   1篇
  2023年   5篇
  2022年   7篇
  2021年   29篇
  2020年   7篇
  2019年   16篇
  2018年   30篇
  2017年   26篇
  2016年   41篇
  2015年   42篇
  2014年   32篇
  2013年   61篇
  2012年   90篇
  2011年   88篇
  2010年   40篇
  2009年   45篇
  2008年   102篇
  2007年   113篇
  2006年   80篇
  2005年   73篇
  2004年   51篇
  2003年   35篇
  2002年   25篇
  2001年   2篇
  2000年   8篇
  1999年   9篇
  1998年   3篇
  1997年   1篇
  1996年   6篇
  1995年   4篇
  1994年   2篇
  1992年   5篇
  1991年   1篇
  1990年   3篇
  1989年   1篇
  1988年   3篇
  1987年   1篇
  1984年   3篇
排序方式: 共有1091条查询结果,搜索用时 15 毫秒
11.
Open in a separate windowOBJECTIVESThis study investigated the efficacy and complications of albendazole use after surgery in patients with pulmonary hydatid cysts.METHODSOne hundred fifty-three consecutive patients who met the study criteria out of 215 patients who received prophylaxis with albendazole after surgery for isolated pulmonary hydatid cysts in our clinic between January 2011 and December 2020 were analysed retrospectively.RESULTSEighty-six out of 153 (56.2%) of cases were male and 67 (43.8%) were female. The average age was 24.6 ± 17.4 (between 3 and 71 years), 76 of them (49.7%) were 18 years old and younger, while 77 (50.3%) were adults. All cases were approached transthoracically and a total of 170 operations were performed on the 153 cases. Fever, weakness and dizziness were reported in only one patient who was given albendazole treatment. A partial increase in liver enzymes was observed in 16 cases (10.5%) after albendazole treatment. Mild leukopoenia and neutropenia were observed in only one of the cases. In 1 case, a second operation was performed 30 months later due to recurrence. Albendazole treatment was not required to be discontinued in any of the cases. Mortality was not observed in any of the cases. Factors such as mean age, cyst size and hospitalization period did not have a statistically significant effect on any changes in liver enzymes tests following albendazole therapy (P > 0.05).CONCLUSIONSAlbendazole treatment can safely be used for postoperative prophylaxis in patients with pulmonary hydatid cysts in a controlled manner without causing serious complications.Subj collection152.  相似文献   
12.
Thrombocytopenia and absent radii (TAR) syndrome is a rare disorder. It may be associated with, for example, as cardiovascular, genitourinary, gastrointestinal, skeletal, neurological, ophthalmic, and facial anomalies. Esophageal atresia is also a rare anomaly associated with genitourinary, skeletal, and cardiovascular anomalies, among others. Here, the authors present a child with TAR syndrome and esophageal atresia with tracheoesophageal fistula. This association has been reported in only one other case in literature.  相似文献   
13.
Possible molecular mechanisms leading to cyclosporine-induced hepatotoxicity has not been cleared yet. Therefore, investigation of antioxidant status of hepatic tissues exposed to cyclosporine A (CsA) and of free radical involvement in the CsA-induced hepatotoxicity seems of importance. For this aim, 20 rabbits were used in the study. In each group (control, CsA, CsA plus vitamin and, vitamin only) there were 5 animals. CsA was given orally (25 mg/kg/day) for 10 days. Vitamins E (100 mg/kg/ day) and C (200 mg/kg/day) combination was injected intramuscularly. After 10th day, animals were killed, and livers were prepared for the enzymatic assays. Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) and, malondialdehyde (MDA) levels were determined in the supernatant fractions. Lowered SOD, unchanged GSH-Px and, increased CAT activities and MDA levels were detected in hepatic tissues of rabbits treated with CsA as compared with controls. In the CsA plus vitamin group, SOD activity was found to be higher, GSH-Px and CAT activities unchanged and MDA levels lower than the CsA group. In the vitamin-treated group, all of the enzyme activities were higher than the controls but MDA levels were unchanged. Correlation analysis revealed some significant differences between the groups. Results suggest that cyclosporine impairs the antioxidant defense system and thus, leads to oxidant stress and peroxidation in rabbit hepatic tissues. It has been established that this process can be prevented by antioxidant vitamin supplementation.  相似文献   
14.
The immunosuppressive agent cyclosporine A (CsA) has been reported to exert measurable hepatotoxic effects. One of the causes leading to hepatotoxicity is thought to be reactive oxygen radical formation. Therefore, this study was designed to elucidate possible relation between cyclosporine A treatment and antioxidant capacity (AOC) of hepatic tissue and, to determine if antioxidant supplementation is beneficial. Cyclosporine A was given to 20 rabbits orally for 10 days. Vitamins E and C combination were given intramuscularly. Vitamin therapy was started 3 days before cyclosporine A treatment and continued for 10 days. In each group (control, cyclosporine A, cyclosporine A+vitamin, and vitamin only) there were five animals. After the animals were sacrificed, their livers were removed to be used in the AOC measurement. AOC was found to be lower in cyclosporine A group compared to control and vitamin groups. Results suggest that reduced antioxidant capacity may play part in the cyclosporine A-induced hepatotoxicity and use of some antioxidants may give beneficial results.  相似文献   
15.
OBJECTIVE: To investigate the relationship between the symptom of mixed urinary incontinence and incontinence severity, urodynamic findings, and treatment response. METHODS: This is a secondary analysis of data from 553 women randomized into a double-blind, placebo-controlled study evaluating duloxetine (serotonin-norepinephrine reuptake inhibitor) for the treatment of predominant stress urinary incontinence. Assessment variables included incontinent episode frequency, the Incontinence Quality of Life Questionnaire (I-QOL), and the Patient Global Impression of Severity Scale (PGI-S). Urge symptoms were identified with three urge I-QOL questions not included in corrected I-QOL calculations. RESULTS: At baseline, 171 women (31%) had mixed urinary incontinence. They had more severe baseline urinary incontinence than did those with stress urinary incontinence (mean incontinent episode frequency 14.3 versus 10.5; PGI-S normal or mild 26.5% versus 70.4%; mean corrected I-QOL 59.1 versus 79.9; all Ps <.001). Baseline urodynamics were performed on a subset of 86 women. Subjects with both urodynamic stress incontinence and detrusor overactivity had less severe incontinence compared with subjects with only urodynamic stress incontinence. Both mixed urinary incontinence and stress urinary incontinence groups had significant decreases in median incontinent episode frequency at a 40 mg per day (62% and 58%, respectively) and 80 mg per day (63% and 65%) duloxetine dose compared with placebo (33% and 44%; all Ps <.05). Response was not dependent on the type of symptoms (interaction P =.47). CONCLUSION: For women presenting with predominant stress urinary incontinence symptoms, the major determinant of concurrent urge symptoms was incontinence severity and not the pathophysiologic condition(s) causing the incontinence; duloxetine demonstrated equal efficacy for women with mixed urinary incontinence and pure stress urinary incontinence.  相似文献   
16.
Neuronal cell death and microglial changes are both hallmarks of neurodegenerative disorders. Therefore, analysis of degenerating neurons related to microglial changes are addressed in many studies of neurosciences. Here we compared different lesion models and two markers for neurodegeneration (Fluoro-Jade and propidium iodide) in an in vivo as well as an in vitro approach. Fluoro-Jade is a specific and selective marker to identify neurons undergoing degeneration. We also tested this marker to analyze neurodegeneration in organotypic hippocampal slice cultures. We could show that activation of microglia is followed by neuronal cell death. Most degeneration markers, such as propidium iodide, only stain the neuronal cell body excluding the axonal and dendritic processes. Fluoro-Jade is able to stain the distal portion as well as the proximal portion of the dissected axon including the axotomized neuron, as so called anterograde and retrograde degeneration after axotomy. To analyze the specificity of Fluoro-Jade, we used primary microglial and BV-2 cells, a well-described murine microglial cell line. Treatment of microglial and BV-2 cells with an excess of L-glutamate induces cell death which could be detected by propidium iodide staining, but not by Fluoro-Jade, demonstrating its specificity to monitor neuronal cell death.  相似文献   
17.
18.
The introduction of hypoxia is well known to cause contraction of pulmonary artery rings in vitro. Despite intensive studies, the cellular mechanisms of hypoxic pulmonary vasoconstriction are still not well defined. In this study, we aimed to determine the contribution of G(S) proteins in hypoxia-induced vasoconstriction in large-diameter sheep pulmonary arteries using cholera toxin (CT). Hypoxia caused further contractions in serotonin but not in NaF-precontracted pulmonary artery rings. However, hypoxic vasoconstriction due to lowering of pO(2) from 97 to 5 mm Hg was totally abolished by preincubation with CT in serotonin-precontracted arteries. These preliminary results indicate that signal transduction mediated by G(s) proteins may be an important mechanism in the hypoxic vasoconstriction of isolated pulmonary arteries of sheep.  相似文献   
19.
This study aims to investigate the role of oxidants in cisplatin-induced nephrotoxicity. Cisplatin was administered intraperitoneally (i.p.) in a single dose (5 mg/kg) and guinea pigs were killed either after 24 h or 7 days. The same experiment was performed using animals treated with vitamins C and E combination and a natural antioxidant extract (SARMEX). The kidneys were then removed to be used in the analyses. Blood samples were also obtained from the animals to be used in routine biochemical assays. Twenty-four hours after treatment there was a significant decrease in the renal activities of total superoxide scavenger activity (TSSA), superoxide dismutase (SOD) and catalase (CAT) accompanied by a rise in malondialdehyde (MDA) levels. After 7 days, the fall in kidney enzymatic activities was far greater, while the increase in blood urea (BUN) and creatinine (CRE) was marked. Treatment with antioxidants causes significant increases in renal TSSA (7 day), non-enzymatic superoxide scavenger activity (NSSA) (24 h and 7 day) and SOD (7 day) activities, does not change glutathione peroxidase (GSH-Px) activity and decreases renal MDA (24 h and 7 day), blood BUN (7 day) and CRE (7 day) levels. Our results suggest that cisplatin treatment impairs both enzymatic and non-enzymatic antioxidant systems and causes peroxidation in the renal tissue, which leads to kidney failure. Antioxidant supplementation strengthens the renal antioxidant system, eliminates oxidation reactions, and prevents cisplatin-induced kidney failure.  相似文献   
20.
Problems related to the central nervous system have a major impact on survival and quality of life. The aim of this retrospective study was to evaluate the incidence of neurological complications after liver transplantation (LT), including both cadaveric and living donor liver transplantation. Between April 2001 and March 2004 174 patients (120 cadaveric liver transplantations, 54 living donor transplantations) were admitted to our intensive care after liver transplantation. Of the transplanted patients 24.7% developed neurological complications. These patients’ stay in the intensive care (14.2 ± 17.2 days) was much longer than that of all admitted patients (8.4 ± 10.5 days, p < 0.05). The most common neurological complications were encephalopathy (72.1%) and seizures (11.6 %). The incidence of neurological complications in living donor liver transplanted patients was significantly lower than in cadaveric transplantation patients (20.4% vs 26.7 %). The cold ischemia time in living donor transplanted patients was significantly shorter in comparison with cadaveric transplanted patients (215 ± 119.3 vs. 383.7 ± 214.7). The survival rate after liver transplantation of patients with neurological complications was lower than that of patients without, but not significantly different (79.1 % vs. 82.4%, p > 0.05). The incidence of neurological symptoms was found to be similar between the patients treated with cyclosporine (25%) and tacrolimus (23.8 %) in this study. In conclusion, there was a high incidence of neurological complications after LT, prolonging the patients’ stay in intensive care significantly. The major neurological manifestation in our patients was encephalopathy followed by seizures. Living donor liver transplantation was associated with a significantly lower incidence of neurological complications compared with patients who had received a cadaveric graft. This might be due to the good quality of the organ and the much shorter cold ischemia time of the graft when the donor was alive.  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