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   3706篇
  免费   257篇
  国内免费   51篇
耳鼻咽喉   16篇
儿科学   71篇
妇产科学   22篇
基础医学   694篇
口腔科学   59篇
临床医学   314篇
内科学   789篇
皮肤病学   301篇
神经病学   276篇
特种医学   99篇
外科学   440篇
综合类   10篇
一般理论   1篇
预防医学   134篇
眼科学   94篇
药学   357篇
中国医学   48篇
肿瘤学   289篇
  2024年   4篇
  2023年   21篇
  2022年   91篇
  2021年   131篇
  2020年   78篇
  2019年   96篇
  2018年   117篇
  2017年   107篇
  2016年   161篇
  2015年   206篇
  2014年   258篇
  2013年   294篇
  2012年   397篇
  2011年   357篇
  2010年   208篇
  2009年   173篇
  2008年   243篇
  2007年   196篇
  2006年   172篇
  2005年   151篇
  2004年   116篇
  2003年   99篇
  2002年   87篇
  2001年   34篇
  2000年   38篇
  1999年   21篇
  1998年   20篇
  1997年   13篇
  1996年   17篇
  1995年   8篇
  1994年   4篇
  1993年   5篇
  1992年   16篇
  1991年   11篇
  1990年   8篇
  1989年   11篇
  1988年   8篇
  1987年   12篇
  1986年   3篇
  1985年   5篇
  1981年   1篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1975年   1篇
  1974年   2篇
  1973年   4篇
  1971年   2篇
  1970年   1篇
  1968年   2篇
排序方式: 共有4014条查询结果,搜索用时 19 毫秒
11.
12.
This empirical study identifies the negative aspects of private health insurance (PHI) by analyzing the association between subjective health conditions, 2 weeks of outpatient care, chronic diseases, and hospitalizations for 1 year. We used frequency analysis, χ2 testing, an analysis of variance, and logistic and multiple logistic regression models to analyze the association between PHI and subjective health conditions, outpatient care, chronic disease status, and hospitalization. The PHI group had good subjective health but had more outpatient care for 2 weeks. There were few chronic diseases in the private insurance group, and there was no significant difference in hospitalizations for 1 year. Hospitalization may occur when essential medical care is required, regardless of health insurance type. This study confirmed that as the PHI lowers the burden of personal medical expenses, the PHI can lead to an increase in the medical resource expenditures on the outpatient medical service and higher public health costs. The government should work to redefine the role of private and national health insurance. Also, the effectiveness of PHI should be reevaluated so that it does not lead to indiscriminate use of medical services by minimizing the burden of private insurance.  相似文献   
13.
We explored the physiological effects of inhaling basil essential oil (BEO) and/or linalool and identified odor-active aroma compounds in BEO using gas chromatography/mass spectrometry (GC–MS) and GC–olfactometry (GC–O). Linalool was identified as the major volatile compound in BEO. Three groups of rats were administered BEO and linalool via inhalation, while rats in the control group were not. Inhalation of BEO for 20 min only reduced the total weight gain (190.67 ± 2.52 g) and increased the forced swimming time (47.33 ± 14.84 s) compared with the control group (219.67 ± 2.08 g, 8.33 ± 5.13 s). Inhalation of BEO for 5 min (392 ± 21 beats/min) only reduced the pulse compared with the control group (420 ± 19 beats/min). Inhalation of linalool only reduced the weight of white adipose tissue (5.75 ± 0.61 g). The levels of stress-related hormones were not significantly different among the groups. The total cholesterol and triglyceride levels decreased after inhalation of BEO for 20 min (by more than −10% and −15%, respectively). Low-density lipoprotein cholesterol levels were lowered (by more than −10%) by the inhalation of BEO and linalool, regardless of the inhalation time. In particular, BEO inhalation for 20 min was associated with the lowest level of low-density lipoprotein cholesterol (53.94 ± 2.72 mg/dL). High-density lipoprotein cholesterol levels increased after inhalation of BEO (by more than +15%). The atherogenic index and cardiac risk factors were suppressed by BEO inhalation. Animals exposed to BEO and linalool had no significant differences in hepatotoxicity. These data suggest that the inhalation of BEO and linalool may ameliorate cardiovascular and lipid dysfunctions. These effects should be explored further for clinical applications.  相似文献   
14.
15.
The purpose of the present paper was to determine error-monitoring ability and its relationship with executive function in patients with schizophrenia. In order to evaluate error-monitoring ability, the error negativity (Ne) and error positivity (Pe) were measured using the Stroop task. The correct-related negativity (CRN) and positivity (Pc) were also measured. In addition, neuropsychological tests were administered in order to evaluate executive function. The patients with schizophrenia had significantly reduced Ne and augmented CRN amplitudes, but the Pe and Pc amplitudes of the patients were comparable to those of the controls. In addition, the Ne amplitude, measured at Fcz was positively correlated with the Trail Making Test (TMT), part B response time, and the categories achieved on the Wisconsin Card Sorting Test (WCST) in patients with schizophrenia. No significant correlations were found between Ne amplitude and performance on the neuropsychological tests in the controls. And no associations were detected between CRN, Pe, Pc amplitudes and neuropsychological performance, in either the patients with schizophrenia or the controls. Reduced Ne amplitudes and augmented CRN amplitudes in patients with schizophrenia suggest the dysfunctional behavior-monitoring system in these patients. The functional significances of Ne and Pe are discussed.  相似文献   
16.
A standard procedure for single-port laparoscopic adrenal surgery has not been established. We retrospectively investigated intraoperative and postoperative outcomes after laparoscopic adrenalectomy through mono port (LAMP) and conventional laparoscopic adrenalectomy to assess the feasibility of LAMP. Between March 2008 and December 2009, 22 patients underwent adrenalectomy at the Department of Surgery, Kangbuk Samsung Hospital. Twelve patients underwent conventional laparoscopic adrenalectomy and 10 patients underwent LAMP. The same surgeon performed all the surgeries. The 2 procedures were compared in terms of tumor size, operating time, time to resumption of a soft diet, length of hospital day, and postoperative complications. The 2 groups were similar in terms of tumor size (30.08 vs. 32.50 mm, P=0.796), mean operating time (112.9 vs. 127 min, P=0.316), time to resumption of a soft diet (1.25 vs. 1.30 d, P=0.805), and length of hospital day (4.08 vs. 4.50 d, P=0.447). Despite 1 patient in the LAMP group experiencing ipsilateral pleural effusion as a postoperative complication, this parameter was similar for the 2 groups (P=0.195). Perioperative mortality, blood transfusion, and conversion to open surgery did not occur. Perioperative outcomes for LAMP were similar to those for conventional laparoscopic adrenalectomy. LAMP appears to be a feasible option for adrenalectomy.  相似文献   
17.

Background  

Robotic thyroidectomy (RT) has recently emerged as a viable approach to thyroid surgery, resulting in better functional and cosmetic outcomes than afforded by open thyroidectomy (OT). The present multicenter study assessed the perioperative outcomes of RT and compared physician perspectives on the musculoskeletal ergonomic parameters associated with OT, endoscopic thyroidectomy (ET), and RT.  相似文献   
18.
Hwangbo Y  Jang JY  Kim HJ  Kim YW  Park SD  Shim J  Dong SH  Kim HJ  Kim BH  Chang YW  Chang R 《Surgery today》2011,41(8):1085-1090
Colonic gastrointestinal stromal tumors (GISTs) account for only 5%-10% of tumors arising in the digestive tract. Spontaneous rupture is a very rare manifestation of a GIST; however, we report what to our knowledge is the first documented case of pneumoretroperitoneum caused by the rupture of a GIST. A 77-year-old woman was admitted to our hospital with acute abdominal pain and hematochezia. Colonoscopy showed luminal narrowing in the sigmoid colon, but no definite mucosal defect. Computed tomography (CT) showed an air-containing heterogeneous mass, 9.7 × 9.3 cm, in the pelvic cavity and a small amount of air in the retroperitoneum. Emergency laparotomy revealed a ruptured sigmoid colonic GIST with localized peritonitis. Pathologic examination confirmed that the tumor was composed mainly of round epithelioid cells. It was immunohistochemically positive for CD34 and negative for C-kit protein. This report describes how we successfully managed pneumoretroperitoneum with localized peritonitis caused by the spontaneous rupture of an epithelioid GIST originating from the sigmoid colon.  相似文献   
19.

Background

Using the da Vinci® robotic system, surgeons can complete secure thyroidectomy without noticeable neck scarring. This study compared the surgical completeness of transaxillary robotic thyroidectomy (RT) with conventional open procedures (OT) in treating papillary thyroid carcinoma (PTC) patients.

Materials and methods

From April 2009 through February 2011, 94 PTC patients underwent total thyroidectomy with central compartment neck dissection (CCND) at Yonsei University College of Medicine. All patients received 1.1 GBq radioactive iodine (RAI) ablation, post-therapy whole-body scans (TxWBS), and diagnostic WBS (DxWBS) 1 year later. We prospectively compared patient clinicopathologic characteristics and surgical completeness between the two groups.

Results

Fifty-one patients underwent OT and 43 underwent RT. Mean age was significantly younger in the RT group. Tumor size, capsular-invasion frequency, multifocality, bilaterality, and central nodal metastasis were not different between the two groups. The number of retrieved nodes during CCND did not significantly differ between the groups. There was no significant difference between the OT and RT groups in stimulated thyroglobulin levels acquired during TxWBS and DxWBS. The RAI uptake ratios at TxWBS were significantly higher in the RT group compared with the OT group; however, follow-up DxWBS showed no difference in RAI uptake ratios. Also, the ablation success rate was similar between the two groups. There were no abnormal findings in follow-up neck ultrasonography in either group.

Conclusion

Remnant thyroid tissue ablation after transaxillary RT was successfully managed by 1.1 GBq RAI. RT showed similar surgical completeness versus conventional OT, and provides a safe and feasible surgical option for PTC patients.  相似文献   
20.
Excessive dietary fat intake causes systemic metabolic toxicity, manifested in weight gain, hyperglycemia, and insulin resistance. In addition, carbohydrate utilization as a fuel is substantially inhibited. Correction or reversal of these effects during high-fat diet (HFD) intake is of exceptional interest in light of widespread occurrence of diet-associated metabolic disorders in global human populations. Here we report that mangiferin (MGF), a natural compound (the predominant constituent of Mangifera indica extract from the plant that produces mango), protected against HFD-induced weight gain, increased aerobic mitochondrial capacity and thermogenesis, and improved glucose and insulin profiles. To obtain mechanistic insight into the basis for these effects, we determined that mice exposed to an HFD combined with MGF exhibited a substantial shift in respiratory quotient from fatty acid toward carbohydrate utilization. MGF treatment significantly increased glucose oxidation in muscle of HFD-fed mice without changing fatty acid oxidation. These results indicate that MGF redirects fuel utilization toward carbohydrates. In cultured C2C12 myotubes, MGF increased glucose and pyruvate oxidation and ATP production without affecting fatty acid oxidation, confirming in vivo and ex vivo effects. Furthermore, MGF inhibited anaerobic metabolism of pyruvate to lactate but enhanced pyruvate oxidation. A key target of MGF appears to be pyruvate dehydrogenase, determined to be activated by MGF in a variety of assays. These findings underscore the therapeutic potential of activation of carbohydrate utilization in correction of metabolic syndrome and highlight the potential of MGF to serve as a model compound that can elicit fuel-switching effects.  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