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   9333篇
  免费   486篇
  国内免费   68篇
耳鼻咽喉   115篇
儿科学   126篇
妇产科学   85篇
基础医学   1244篇
口腔科学   238篇
临床医学   542篇
内科学   2262篇
皮肤病学   235篇
神经病学   774篇
特种医学   453篇
外科学   1747篇
综合类   50篇
一般理论   1篇
预防医学   212篇
眼科学   82篇
药学   524篇
中国医学   24篇
肿瘤学   1173篇
  2023年   81篇
  2022年   113篇
  2021年   310篇
  2020年   140篇
  2019年   228篇
  2018年   273篇
  2017年   209篇
  2016年   284篇
  2015年   276篇
  2014年   336篇
  2013年   371篇
  2012年   605篇
  2011年   694篇
  2010年   394篇
  2009年   363篇
  2008年   543篇
  2007年   640篇
  2006年   589篇
  2005年   606篇
  2004年   535篇
  2003年   493篇
  2002年   518篇
  2001年   100篇
  2000年   83篇
  1999年   110篇
  1998年   115篇
  1997年   118篇
  1996年   77篇
  1995年   89篇
  1994年   42篇
  1993年   61篇
  1992年   47篇
  1991年   44篇
  1990年   52篇
  1989年   32篇
  1988年   40篇
  1987年   35篇
  1986年   21篇
  1985年   13篇
  1984年   11篇
  1983年   18篇
  1982年   13篇
  1981年   14篇
  1980年   11篇
  1979年   13篇
  1978年   15篇
  1975年   10篇
  1974年   12篇
  1968年   9篇
  1967年   15篇
排序方式: 共有9887条查询结果,搜索用时 176 毫秒
101.
The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study.  相似文献   
102.
Scavenger receptor class B type I (SR-BI), a CD36 family member, plays a key role in high-density lipoprotein (HDL) metabolism, reverse cholesterol transport, and whole body cholesterol homeostasis, and is shown to be involved in the development of atherosclerosis in mice. In this report, we describe the effects of the adenoviral overexpression of human SR-BI (hSR-BI) in New Zealand White (NZW) rabbits, a wild-type animal model that expresses cholesteryl ester transfer protein (CETP) in plasma, displays a manlike lipoprotein profile, and is susceptible to atherosclerosis. A total of 1×1012 adenoviral particles containing either hSR-BI or lacZ complementary deoxyribonucleic acid (control) were infused into the ear vein of NZW rabbits. Transgene expression was ascertained by TaqMan Real Time polymerase chain reaction measurements. Rabbits infected with Ad/hSR-BI (adenoviral plasmids containing hSR-BI) showed a faster clearance of administered [3H]HDL cholesterol and significantly decreased apolipoprotein (apo) A-I levels when compared to control rabbits, respectively. Interestingly, we found markedly increased levels of low-density lipoprotein (LDL) cholesterol exclusively in SR-BI-overexpressing rabbits. These changes were not accompanied by alterations in LDL receptor expression but by increased levels of CE transfer in these animals. By lowering HDL cholesterol and increasing plasma apoB-containing lipoprotein levels, the overexpression of SR-BI leads to a lipoprotein pattern, which is believed to enhance the development of atherosclerosis. The role of SR-BI in lipoprotein metabolism and atherogenesis in rabbits—a CETP-expressing animal model displaying a manlike lipoprotein profile—may therefore be different from the one found in rodents.  相似文献   
103.
104.
31P and 23Na nuclear magnetic resonance (NMR) spectroscopy was employed to study the dynamic changes in intracellular high-energy phosphates and sodium during 15min of forebrain ischemia and recirculation in in vivo rat brain. In the presence of the shift reagent Dysprosium triethylenetetramine-N,N,N,N,N,N-hexaacetic and [Dy(TTHA)], the sodium peak separated into two peaks, unshifted and shifted. During 15min of ischemia, the unshifted sodium peak decreased and the shifted sodium peak increased. With recirculation, the unshifted and the shifted sodium peaks returned to the preischemia level within 10min, but the shifted one increased during 30–60min. Intracellular high-energy phosphates and intracellular pH (pHi) decreased during 15min of ischemia and returned to the preischemia levels within 20min of recirculation. We conclude that the decrease in unshifted sodium peak during ischemia is due to the decrease in subarachnoid sodium and the cellular influx of interstitial sodium would be minimum. The increase in shifted sodium peak during ischemia is considered to be due to the dilatation of cerebral blood vessels and the increase in interstitial sodium which was transported from subarachnoid space.(Kurata M: 31P and 23Na nuclear magnetic resonance study on forebrain ischemia in rats with shift reagent Dy(TTHA). J Anesth 7: 325–333, 1993)  相似文献   
105.
Iwabuchi  Satoru  Handa  Masashi  Usuda  Katsuo  Sato  Masami  Kondo  Takashi  Tanita  Tatsuo  Fujimura  Shigefumi 《Surgery today》1994,24(11):1014-1018
A 52-year-old Japanese man with a slow-growing chondroma originating from the sternal bone was referred to our hospital. A subtotal resection of the sternum was performed, hereafter termed the sandwich method, and an originally designed prosthesis made from ultra-high-molecular-weight polyethylene and Marlex mesh was used for reconstruction. The postoperative course was uneventful without any symptoms due to paradoxical movement of the chest or regional abscess, and no disturbance in the movement of the upper limbs, such as a surgical sequelae, was observed.  相似文献   
106.
Prior injection of an anticancer agent and Lipiodol mixture is a key point for the treatment of hepatocellular carcinoma (HCC). We therefore prepared a new, improved emulsion of Lipiodol containing a high dose ofcis-diamminedichloroplatinum (CDDP) and epirubicin by replacing the ionic contrast medium (Urografin 67) with a nonionic contrast medium (Iopamidol; Iopamiron 300) and adding phosphatidyl choline. This CDDP-epirubicin-Lipiodol emulsion (CELE) was examined pharmacologically and chemically with the following results. The size of these particles is less than 10 m (diameter) for up to 24 h; the release of 28%–34% of the CDDP and 80%–90% of the epirubicin was estimated in the dissolution test, and 85% of the CDDP and 35% of the epirubicin was retained in the organs in the moment calculation. CELE was injected into 58 HCC patients via a celiac angiographic catheter. In 36 of these patients, the CELE injection was followed by transcatheter arterial embolization (TAE) therapy. Following the administration of CELE as one-shot injection therapy for stage IV HCC, the 1-year survival rate was 59% and the 2-year survival rate was 27%. Moreover, in patients (stage II, 12; stage III, 8; stage IV, 16) who received CELE and subsequently underwent TAE therapy, the 1-year survival rate was 90% and the 2-year survival rate was 67%. The nonionic contrast medium with Lipiodol forms finer emulsified particles, and these particles are more capable of penetrating into the tumor. In addition, the greater pharmacological stability of these particles provides a slow-release effect and prolonged stability of their shape. Finally, theoretically, the use of two major anticancer agents such as CDDP and epirubicin showed a greater clinical effect in the treatment of HCC than either our earlier suspension or a single anticancer agent.Work presented at the Third International Symposium on Treatment of Liver Cancer, Seoul, Korea, 12–13 February 1993  相似文献   
107.
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology of TAWH.  相似文献   
108.
Factors associated with knee pain were investigated using 871 self-administered questionnaires (405 men and 466 women) from residents aged over 30 years in a rural area of Japan. The prevalence of knee pain increased with age, particularly in women over 50. It was significantly higher in women than in men. Body mass index (BMI) was significantly related to knee pain in women, though not in men. With reference to occupational factors, frequent heavy lifting on the job was significantly associated with knee pain in both men and women, whereas job-related standing and walking showed no such relationship. As for living conditions, residence on rather steep mountain slopes and the habit of sitting on Japanese tatami mats were significant factors related to knee pain in men, but not in women. There was no association of knee pain with the style of toilet (Japanese or Western). After controlling for all significant factors by multiple logistic regression analysis, age, heavy lifting, and residence on steep slopes were found to be independent factors related to knee pain in men; and age, BMI, and heavy lifting were the factors in women.  相似文献   
109.
A case of female alcoholic who developed liver cirrhosis with small amounts of alcohol by the common use of contraceptive agent was reported. A case was a 33-year-old female who had complained of systemic edema and jaundice. She had been drinking alcohol, while she had been taking the contraceptive agent from 20-year-old. On admission, she had a large amount of ascites with jaundice. She was diagnosed as liver cirrhosis and hepatic failure by CT scanning of abdomen and laboratory data. Her condition was temporarily improved by the abstinence and the treatment. Since she drank under hospitalization, she had to change the hospital and died after 2 months. She had been drinking for only 10 years. Her cumulative alcohol intake was also very small. She may have developed alcoholic cirrhosis with small amount of alcohol because of common use of contraceptive agent with drinking.  相似文献   
110.
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