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   14806篇
  免费   705篇
  国内免费   101篇
耳鼻咽喉   144篇
儿科学   209篇
妇产科学   109篇
基础医学   1736篇
口腔科学   270篇
临床医学   878篇
内科学   3759篇
皮肤病学   259篇
神经病学   1166篇
特种医学   797篇
外科学   2621篇
综合类   64篇
预防医学   487篇
眼科学   330篇
药学   959篇
中国医学   56篇
肿瘤学   1768篇
  2023年   107篇
  2022年   202篇
  2021年   384篇
  2020年   190篇
  2019年   272篇
  2018年   313篇
  2017年   305篇
  2016年   359篇
  2015年   359篇
  2014年   480篇
  2013年   562篇
  2012年   859篇
  2011年   974篇
  2010年   587篇
  2009年   465篇
  2008年   853篇
  2007年   884篇
  2006年   858篇
  2005年   935篇
  2004年   836篇
  2003年   827篇
  2002年   853篇
  2001年   238篇
  2000年   220篇
  1999年   258篇
  1998年   236篇
  1997年   160篇
  1996年   177篇
  1995年   146篇
  1994年   135篇
  1993年   124篇
  1992年   162篇
  1991年   106篇
  1990年   123篇
  1989年   114篇
  1988年   87篇
  1987年   76篇
  1986年   75篇
  1985年   62篇
  1984年   55篇
  1983年   44篇
  1982年   40篇
  1981年   31篇
  1979年   33篇
  1975年   31篇
  1974年   32篇
  1973年   42篇
  1969年   38篇
  1968年   35篇
  1967年   31篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Summary In order to investigate possible effects of smoking and drinking on the metabolism of toluence in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits.  相似文献   
12.
We established a novel murine model of pharyngeal candidiasis maintaining stable yeast population and local symptoms characteristic of pharyngeal thrush. The persistent Candida-infection was prolonged by inhalation of beclomethasone dipropionate corticosteroid. The severity of infection lesions was evaluated by determining viable cell number of Candia albicans and scores representing symptomatic curd-like white patch on pharyngeal tissue. The utility of this model was shown by the disappearance of lesions and fungal cells after treatment with fluconazole (FLCZ). The model would be useful for evaluating new chemotherapeutic or immunotherapeutic approaches against pharyngeal candidiasis, as well as in pathological studies.  相似文献   
13.
BACKGROUND: The oncologic benefit of avoiding allogenic blood transfusion in oesophageal cancer resection has not been studied. METHODS: The medical records of 68 patients (Auto group) who underwent a potentially curative oesophageal cancer resection without allogenic blood transfusion from 1996 to 1999 receiving 800 g of autologous blood donated preoperatively, and 97 patients (Allo group) who underwent the same operation with allogenic blood transfusion from 1990 to 1995 were compared. RESULTS: There were no differences in age, gender, stage of disease, number of retrieved nodes, or perioperative hemoglobin concentration between the two groups. The survival of the 45 patients with nodal involvement in the Auto group was better than that of the 59 patients in the Allo group (p=0.0435), and the survival of the 35 patients with T3 or T4 lesions in the Auto group was better than that of the 61 patients in the Allo group (p=0.0408). According to logistic regression analysis, allogenic blood transfusion correlated with tumour recurrence in patients with either nodal involvement or a T3-4 lesion. The natural killer cell activity remained higher in the Auto group than in the Allo group (p<0.05). CONCLUSION: Avoidance of allogenic blood transfusion favorably effected the survival of patients with oesophageal cancer at risk for recurrence.  相似文献   
14.
A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented.  相似文献   
15.
A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS.  相似文献   
16.
The medial globus pallidus plays a crucial role in generation of L‐DOPA‐induced dyskinesia in patients with Parkinson's disease. The 6‐hydroxydopamine‐lesioned rat exhibiting behavioral sensitization to L‐DOPA is one useful animal model for examining L‐DOPA‐induced dyskinesia. To determine neuropathological abnormality responsible for behavioral sensitization, the medial globus pallidus and the substantia nigra reticulata in 6‐hydroxydopamine‐lesioned rats treated with L‐DOPA were examined. Intermittent L‐DOPA treatment induced hypertrophy of the lesioned‐side of medial globus pallidus and substantia nigra reticulata of 6‐hydroxydopamine‐lesioned rats with behavioral sensitization to L‐DOPA. Additionally, coadministration of a 5‐HT1A receptor agonist, 8‐hydroxy‐2(di‐n‐propylamino)tetralin with L‐DOPA, alleviated the hypertrophy with improvement of the behavioral sensitization. These results suggest that hypertrophy of the medial globus pallidus and substantia nigra reticulata is associated with induction of behavioral sensitization to L‐DOPA in 6‐hydroxydopamine‐lesioned rats. Therefore, neuropathological changes corresponding to hypertrophy might underlie L‐DOPA‐induced dyskinesia in patients with Parkinson's disease.  相似文献   
17.
A case of inflammatory pseudosarcoma of the urinary bladder in a 35 year-old Japanese male is presented. This benign lesion can easily be mistaken for spindle cell sarcoma since it consists of rhabdomyoblast like elongated strap cells showing infiltrative growth, and whether it is benign or malignant is difficult to determine by microscopic examination. In this case, spindle cell proliferation extended among bundles of the superficial muscle layer. However, no abnormal mitoses, severe nuclear atypia or cellular pleomorphism could be seen, thus indicating inflammatory pseudosarcoma. Although the lesion was not completely resected, no recurrent disease has been clinically observed for two years following transurethral resection. Urologists and surgical pathologists must be able to detect this lesion in order to avoid unnecessary surgical procedures. Acta Pathol Jpn 42: 760 765,1992.  相似文献   
18.
19.
A case of polycythemia vera complicated by chronic renal failure under maintenance hemodialysis requiring parathyroidectory (PTH) for secondary hyperparathyroidism (2° HPT) is reported. A 62 year old female presented with 75000 white blood cells (WBC)/μl, 703×104 red blood cells (RBC)/μl, 23×104 platelets (PLT)/μl, hyperuricemia and hypertension in 1970 and the diagnosis of polycythemia vera was made. Hemodialysis was started in October 1974 for chronic renal failure. Blood cells in peripheral blood rapidly decreased in number after the beginning of dialysis, reaching the level of 10000∼20000 WBC/μl, and 150∼250×104RBC/μl. In August 1988, marked bone resorption in X-ray picture and high serum alkaline phosphatase and parathyroid hormone (PTH) noted along with 17400 WBC/μl, 370×104RBC/μl and 35.9×104PLT/μl. After subtotal PTX removing 3.21g parathyroid gland, serum PTH rapidly fell. At 3 months after PTX, WBC rose to 23600/μl, RBC 372×104/μl and PLT 94.0×104/μl. At 6 months, WBC was to 31000/μl, RBC 429×104/μl and PLT 78.0×104/μl, suggesting an inhibitory action of PTH on not only RBC, but also WBC and PLT.  相似文献   
20.
A rare case of jejunal carcinoma coexisting with adenoma, situated 120 cm distal to the ligament of Treitz in a 53 year old male, is reported herein. We also review cases of adenoma and carcinoma in the jejunum and ileum from the Japanese literature, and discuss the histogenesis of carcinoma of the jejunum and ileum.  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