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   23640篇
  免费   1303篇
  国内免费   149篇
耳鼻咽喉   180篇
儿科学   582篇
妇产科学   379篇
基础医学   2959篇
口腔科学   638篇
临床医学   1619篇
内科学   6216篇
皮肤病学   429篇
神经病学   2077篇
特种医学   766篇
外科学   3700篇
综合类   131篇
一般理论   1篇
预防医学   623篇
眼科学   350篇
药学   1697篇
中国医学   27篇
肿瘤学   2718篇
  2023年   125篇
  2022年   213篇
  2021年   450篇
  2020年   245篇
  2019年   317篇
  2018年   470篇
  2017年   324篇
  2016年   392篇
  2015年   470篇
  2014年   567篇
  2013年   689篇
  2012年   1045篇
  2011年   1149篇
  2010年   647篇
  2009年   544篇
  2008年   951篇
  2007年   1117篇
  2006年   1047篇
  2005年   1085篇
  2004年   1020篇
  2003年   958篇
  2002年   987篇
  2001年   941篇
  2000年   914篇
  1999年   857篇
  1998年   299篇
  1997年   233篇
  1996年   273篇
  1995年   162篇
  1994年   160篇
  1993年   148篇
  1992年   534篇
  1991年   493篇
  1990年   506篇
  1989年   460篇
  1988年   431篇
  1987年   431篇
  1986年   375篇
  1985年   393篇
  1984年   279篇
  1983年   191篇
  1979年   214篇
  1978年   143篇
  1977年   138篇
  1974年   129篇
  1971年   136篇
  1970年   132篇
  1969年   128篇
  1968年   139篇
  1967年   141篇
排序方式: 共有10000条查询结果,搜索用时 801 毫秒
121.
Early gastric cancer manifested as brain metastasis: Report of a case   总被引:1,自引:0,他引:1  
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis.  相似文献   
122.
123.
Case 1: A 48-year-old male with stage 4 penile cancer is reported. We used peplomycin (PEP) and cisplatinum (CDDP) for preoperative chemotherapy. Chemotherapy was effective. Radical surgery with bilateral inguinal lymphadenectomy was done and skin defect was covered with a skin flap. Case 2: A 61-year-old male with stage 4 penile cancer underwent radical surgery after modified MBD therapy with methotrexate (MTX), PEP and CDDP. Emasculation with skin resection and inguinal and pelvic lymphadenectomy were performed. The skin defect was deep and wide. It was covered with a glacilis myocutaneous skin flap. Distal end of the flap became necrotic. It was covered with tensor fascia lata myocutaneous flap. Seventeen patients with penile cancer were treated between 1972 and 1990 at Mie University Hospital. Nine patients were in stage 1, 4 stage 2, 1 stage 3, 3 stage 4. Treatment consisted of surgery (3), surgery+chemotherapy (10), surgery+chemotherapy+irradiation (2), chemotherapy+irradiation (1), and surgery+irradiation(1). Cancer death was observed in 2 cases (stage 2), 2 patients died of other diseases, 10 are alive, and 3 patients were lost to follow up.  相似文献   
124.
Recently, plasma fructosamine concentration has been used as an indication of mean plasma glucose level preceding at last 1 to 2 weeks. In the present study, to characterize the clinical significance and problems of plasma fructosamine concentration in aged subjects (greater than or equal to 65 yrs), we determined plasma fructosamine concentration as well as serum albumin, total protein, HbA1, AbA1c and fasting plasma glucose concentrations in 81 (less than 65 yrs) non-diabetic subjects (group A), 161 aged (greater than or equal to 65 yrs) non-diabetic subjects and 26 aged diabetics (group D). Aged non-diabetic subjects were further classified into 75 subjects with good ADL (group B) and 86 with poor ADL (group C). The normal limit of plasma fructosamine concentration (mean +/- 2SD) in group A was 24% higher (3.1 mmol/l) than that in group B (2.5 mmol/l) but the plasma fructosamine/serum albumin ratio (F/ALB) was similar in these two groups. Plasma fructosamine correlated negatively (p less than 0.01) with age. This aging effect was explained by the reduced serum albumin in aged subjects. However, in group C, reduced plasma albumin was not associated with reduced plasma fructosamine. Plasma fructosamine corrected by albumin (F/ALB) is a useful parameter of blood glucose control in aged subjects. In aged subjects with poor ADL, HbA1, HbA1c and plasma glucose should be determined with fructosamine.  相似文献   
125.
p = 0.0007) and tumor necrosis (TN) (HMC: p = 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all patients ( p = 0.0086 and p = 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant independent prognostic factor associated with long-term survival in Japanese breast cancer patients.  相似文献   
126.
A total of 594 flat colorectal polyps, removed at endoscopy, were histologically classified into non-neoplastic (n=49) and neoplastic (n=545) polyps. Non-neoplastic polyps were subdivided into metaplastic (n=45) and hyperplastic (n=4), whereas neoplastic polyps were subdivided into adenomas (n=481), intramucosal carcinomas (n=28) and invasive adenocarcinomas (n=36). Several adenoma phenotypes were discerned: tubular (n=375), serrated (n=59), villous (n=39), mixed (n=7) and fenestrated (n=1). Intramucosal carcinomas were subdivided into tubular (n=26) and serrated (n=2), and invasive adenocarcinomas into tubular (n=32), serrated (n=3) and fenestrated (n=1). The microscopic characteristics of each histologic phenotype described in this communication are defined and illustrated.  相似文献   
127.
Casein was modified by glucose, diacetyl, or hexanal at 50 degrees C, RH 75% for 1, 7, or 11 days. The chemical changes and digestibility in vitro of these nondialyzable caseins were investigated. The effects of these nondialyzable caseins supplemented with lost amino acids, on rats were studied by pair-feeding for 2 months. It was observed that internal organs such as liver, spleen, kidney, stomach, small intestine, cecum, colon and rectum were mostly unchanged. Biochemical values such as hematocrit, cholesterol, triglyceride, GPT, and GOT were also unchanged. However, the quantity of leucocytes was increased and serum glucose was decreased by feeding rats with modified caseins. Significant decrease in weight gain of rats fed with modified casein was observed, and the rate of decrease depended on the degree of modification of casein by carbonyl compounds. From these results, we supported the suggestion that some inhibitory or antinutritional compounds might be formed during the modification of casein by carbonyl compounds.  相似文献   
128.
Bladder outlet obstruction has been shown to cause detrusor contractile dysfunction. To determine if alterations in bladder metabolism may in part underlie these functional defects, we investigated the effects of mild outlet obstruction on the glucose metabolism of the rabbit urinary bladder. Mild outlet obstruction was created in mature male rabbits by the surgical placement of a silicon sleeve around the bladder neck. Two weeks after surgery, the in vitro ability of the obstructed bladder tissues to metabolize glucose was compared to that of the controls. The results can be summarized as follows: 1) The bladder wet weight increased 2.3-fold following two weeks of obstruction. 2) Obstructed bladder tissues had a reduced glucose consumption as compared to the controls. 3) CO2 generation was significantly reduced by 31% in obstructed bladder tissues whereas lactate formation increased significantly by 22%. 4) Tissue concentrations of ATP, creatine phosphate, and glycogen before incubation showed no significant differences between control and obstructed bladder tissues. In summary, bladder tissues following two weeks obstruction showed a decrease in aerobic metabolism and an increase in anaerobic metabolism. Previous studies have indicated that the ability of the bladder to maintain a contraction and empty may be directly related to aerobic metabolism. Therefore, the decrease in aerobic metabolism (even in the presence of increased anaerobic metabolism) may in part explain the decreased ability of the obstructed bladder to empty.  相似文献   
129.
During the anhepatic phase of orthotopic liver transplantation, the veno-venous bypass has been used to keep systemic hemodynamics (SHD) in a stable condition. In this study, changes of SHD and oxygen transport and consumption (OTC) during the anhepatic phase used the passive bypass (PB) with Anthron bypass tubes were compared with those used the pump-driven bypass (PDB) with a centrifugal pump in mongrel dogs. Moreover the effects of the increased instillation rate and administration of dobutamine on SHD and OTC were evaluated. The portal venous and inferior vena caval pressure were increased in PB group, but not in PDB group. Whenever PB or PDB was used, cardiac index and oxygen consumption were markedly decreased caused by hypovolemia. In PDB group trebled the instillation rate, SHD and oxygen consumption were not improved. These results suggested that the primarily cardiovascular depression during the anhepatic phase was related to the disturbance of SHD. When dobutamine was administered and the instillation rate was trebled in PDB group, SHD and OTC were maintained in a favorable state. It is concluded that PDB, administration of dobutamine and sufficient instillation are advantageous to maintain systemic hemodynamic stability during the anhepatic phase of orthotopic liver transplantation.  相似文献   
130.
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