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   27061篇
  免费   1799篇
  国内免费   246篇
耳鼻咽喉   424篇
儿科学   418篇
妇产科学   590篇
基础医学   3921篇
口腔科学   695篇
临床医学   2364篇
内科学   5145篇
皮肤病学   586篇
神经病学   2021篇
特种医学   1617篇
外科学   4344篇
综合类   284篇
一般理论   10篇
预防医学   1123篇
眼科学   664篇
药学   2338篇
  1篇
中国医学   270篇
肿瘤学   2291篇
  2023年   162篇
  2022年   383篇
  2021年   711篇
  2020年   389篇
  2019年   663篇
  2018年   721篇
  2017年   597篇
  2016年   690篇
  2015年   1022篇
  2014年   1257篇
  2013年   1426篇
  2012年   2135篇
  2011年   2094篇
  2010年   1294篇
  2009年   1190篇
  2008年   1629篇
  2007年   1554篇
  2006年   1451篇
  2005年   1376篇
  2004年   1240篇
  2003年   1081篇
  2002年   957篇
  2001年   780篇
  2000年   762篇
  1999年   603篇
  1998年   215篇
  1997年   203篇
  1996年   182篇
  1995年   150篇
  1994年   128篇
  1993年   102篇
  1992年   244篇
  1991年   184篇
  1990年   175篇
  1989年   167篇
  1988年   144篇
  1987年   103篇
  1986年   95篇
  1985年   71篇
  1984年   78篇
  1983年   51篇
  1982年   53篇
  1981年   46篇
  1980年   43篇
  1979年   56篇
  1978年   44篇
  1977年   47篇
  1974年   37篇
  1972年   44篇
  1971年   42篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Annals of Surgical Oncology - Biomarker changes in patients with residual disease (RD) after neoadjuvant systemic therapy (NAT) have unclear consequences. This study examined the prevalence of...  相似文献   
102.
ObjectiveTo assess the feasibility of enrollment and collecting patient-reported outcome (PRO) data as part of routine clinical urologic care for bladder and prostate cancer patients and examine overall patterns and racial variations in PRO use and symptom reports over time.Subjects/Patients and MethodsWe recruited 76 patients (n = 29 Black and n = 47 White) with prostate or bladder cancer at a single, comprehensive cancer center. The majority of prostate cancer patients had intermediate risk (57%) disease and underwent either radiation or prostatectomy. Over half (58%) of bladder cancer patients had muscle invasive disease and underwent cystectomy.Patients were asked to complete PRO symptom surveys using their preferred mode [web- or phone-based interactive voice response (IVR)]. Symptom summary reports were shared with providers during visits. Surveys were completed at 3 time points and assessed urinary, sexual, gastrointestinal, anxiety/depression, and sleep symptoms. Feasibility of enrollment and survey completion were calculated, and linear mixed effects models estimated differences in outcomes by race and time.ResultsSixty three percent of study participants completed all PRO measures at all 3 time points. Black patients were more likely to select IVR as their survey mode (40% vs. 13%, P < 0.05), and less likely to complete all surveys (55% vs. 74%, P = 0.13). Patients using IVR were also less likely to complete all surveys (41% vs. 69%, P = 0.046).ConclusionsReported preferences for survey mode and completion rates differ by race, which may influence survey completion rates and highlight potential obstacles for equitable implementation of PROs into clinical care.  相似文献   
103.
104.
105.
Pancreatic panniculitis occurs in up to three percent of all patients with pancreatic disease. This cutaneous eruption, as implied by the name, is almost exclusively encountered in the context of pancreatic disorders, such as pancreatitis or pancreatic carcinoma. We report three cases in which histopathologic examination demonstrated hallmarks of pancreatic panniculitis occurring in patients without any history or evidence of pancreatic disorder. These nonpancreatic pancreatic panniculitis eruptions might be underreported in the literature.  相似文献   
106.
BackgroundBone tumors can cause severe pain and poor quality of life due to recurrence and non-achievement of complete remission after surgery, chemotherapy, or radiotherapy. Radiofrequency ablation (RFA) can be considered for minimally invasive treatment of bone tumors that are difficult to radically excise. In this study, RFA was performed for bone tumors that were difficult to radically excise and did not respond to surgery, chemotherapy, or radiotherapy due to their large sizes and/or locations. The purpose of this study was to retrospectively analyze the clinical characteristics and survival rates of bone tumors after RFA and provide one more treatment option for the future.MethodsThere were 43 patients with bone tumors who underwent percutaneous RFA at our hospital from April 2007 to October 2017. The median age of the patients was 59 years (range, 31–75 years), and the median follow-up duration was 67.2 months (range, 10.2–130.5 months). Of the 43 patients, 26 were male and 17 were female. Thirty-four cases were metastatic bone tumors, 5 were chordomas, 3 were osteosarcomas, and 1 was a giant cell tumor. Pain and functional ability of the patients were evaluated using a visual analog scale (VAS) and the Musculoskeletal Tumor Society (MSTS) functional scoring system, respectively. Scores were recorded preoperatively, 1 week postoperatively, and 4 weeks postoperatively. The 1-year, 2-year, and 5-year survival rates were evaluated using the Kaplan-Meier method.ResultsThe mean VAS score was 8.21 preoperatively. The mean VAS score at 1 week, 4 weeks, 12 weeks, and 24 weeks postoperatively were 3.91, 3.67, 3.31, and 3.12, respectively. The mean preoperative MSTS score was 64.0% (range, 32%–87%). The mean postoperative MSTS score was 71.0% (range, 40%–90%). The 1-year, 2-year, and 5-year survival rates were 95.3%, 69.8%, and 30.2%, respectively.ConclusionsAs per our study findings, RFA was effective in reducing pain and improving functional ability of patients with bone tumors that were difficult to radically excise.  相似文献   
107.
Indwelling urethral catheter placement is a common and comparatively safe procedure. Misplacement of a urethral catheter into the upper urinary tract is unusual, and only a few cases have been reported. We describe the case of a 43-year-old man who presented with oliguria and had a history of chemotherapy for known metastatic lung cancer. As he had no history of urological disease, urethral catheterization was expected to be uneventful. The catheter was unable to be pulled back to the bladder neck once the balloon was inflated, and the patient expressed discomfort. Subsequent computed tomography revealed that the tip of the catheter was placed in the middle of the right ureter. Unbeknownst to the physicians before urethral catheterization, the patient had severe lower urinary tract symptoms and urinary bladder dysfunction with hydronephrosis, likely due to chemotherapy. Based on the patient’s symptoms and imaging results, we judged the possibility of severe ureteral injury to be low. The malpositioned catheter was removed uneventfully after complete balloon deflation and then reinserted properly. He was admitted to the medical department but died as a result of an exacerbation of the underlying disease unrelated to the incident. If urethral catheter placement seems abnormal, physicians should aspirate and irrigate to confirm correct positioning before balloon inflation; then, they should carefully pull the inflated balloon near the neck of the bladder while monitoring the patient’s symptoms. Although urethral catheter placement is comparatively safe, physicians must keep in mind that patients who have undergone chemotherapy might be at a risk for this rare complication.  相似文献   
108.
Imaging-guided palliative therapy of recurrent and/or inaccessible head and neck tumors may soon become clinically practical since sensitive and noninvasive monitoring techniques of energy deposition in tissues are now available. Interstitial tumor therapy (ITT) is a technique whereby a source of energy (laser, radiofrequency, ultrasonic, cryoenergy, etc.) is directly applied into tumors at various depths. Recent studies have demonstrated the efficiency of ultrasound (UTZ) and magnetic resonance imaging (MRI) for real and/or "near" real time tumor and vessel identification as well as monitoring and quantifying energy-induced tissue damage. We now report our initial clinical experience with patients in which UTZ and/or MRI-guided ITT techniques were successfully applied for the treatment of recurrent, nonresectable, local, and/or metastatic head and neck carcinomas. Patients were treated on an outpatient basis either in the operating room or in an upgraded specially equipped SIGNA 1.5T MR suite. Most patients tolerated these procedures well and were successfully palliated for periods ranging from 3 months to 5 years posttreatment. The upgrades introduced in a standard MRI suite, the clinical experience, and future perspectives will be reviewed.  相似文献   
109.
In liver injury, perisinusoidal cells known as lipocytes (Ito cells) undergo "activation," acquiring smooth muscle-like features and a contractile phenotype. To assess whether contraction of these cells is regulated by nitric oxide (NO), we examined the production of NO by lipocytes and the effect of NO on lipocyte contractility. Cultured lipocytes were exposed to cytokines and/or LPS. Single agents had little or no effect on the level of inducible NO synthase (iNOS) mRNA. However, interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), or LPS in combination with interferon-gamma (IFN-gamma) stimulated iNOS mRNA, which was present within 4 h after exposure. iNOS mRNA levels were paralleled by changes in nitrite (a metabolic product of NO). Intraperitoneal administration of IFN-gamma, TNF-alpha, and LPS led to rapid induction of iNOS mRNA in lipocytes, confirming in vivo the culture findings. Ligation of the common hepatic bile duct, which induces periportal-based liver injury, stimulated iNOS mRNA in lipocytes. Transforming growth factor-beta 1 decreased IFN-gamma/TNF-alpha--stimulated iNOS mRNA and nitrite. Finally, the effect of NO on lipocyte contractility was examined. In cells incubated with IFN-gamma and TNF-alpha, the contractile response to either serum or endothelin-1 was blocked. Contraction was restored entirely by an inhibitor of NO synthase, NG-monomethylarginine. Furthermore, 8-bromoguanosine 3':5'-cyclic monophosphate and sodium nitroprusside inhibited lipocyte contractility, consistent with the effect of NO induced by cytokines. We conclude that NO is a potent modulator of lipocyte contractility and may regulate this function by autocrine (or intracrine) mechanisms. Moreover, NO may play an important role in liver injury, countering the effect of contractile agonists on lipocytes.  相似文献   
110.
Examines the extent to which quality assurance can be conceived as a rational endeavour, particularly in ethical terms. Examines the Weberian distinction between rationality as values as an "end in themselves" and values conceived in terms of a "means-ends" distinction. While the emergence and existence of quality assurance can be viewed from either of these two perspectives, both entail a number of problems. Suggests that quality assurance, while appearing rational, fails at a crucial point for two reasons. First, while rationality is a relational concept, quality within the health service does not appear to function in such a manner; and second that quality assurance often neglects to evaluate its own activities. Claims that in both instances quality assurance acts more in terms of its functional role than in terms of its rationality.  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