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   4074篇
  免费   178篇
  国内免费   15篇
耳鼻咽喉   66篇
儿科学   94篇
妇产科学   22篇
基础医学   452篇
口腔科学   81篇
临床医学   218篇
内科学   792篇
皮肤病学   38篇
神经病学   464篇
特种医学   212篇
外科学   809篇
综合类   26篇
预防医学   81篇
眼科学   46篇
药学   269篇
中国医学   6篇
肿瘤学   591篇
  2023年   27篇
  2022年   54篇
  2021年   70篇
  2020年   46篇
  2019年   51篇
  2018年   81篇
  2017年   60篇
  2016年   71篇
  2015年   66篇
  2014年   78篇
  2013年   114篇
  2012年   202篇
  2011年   213篇
  2010年   132篇
  2009年   128篇
  2008年   183篇
  2007年   212篇
  2006年   225篇
  2005年   200篇
  2004年   205篇
  2003年   173篇
  2002年   193篇
  2001年   136篇
  2000年   132篇
  1999年   150篇
  1998年   46篇
  1997年   52篇
  1996年   42篇
  1995年   57篇
  1994年   34篇
  1993年   37篇
  1992年   85篇
  1991年   84篇
  1990年   74篇
  1989年   57篇
  1988年   51篇
  1987年   52篇
  1986年   62篇
  1985年   53篇
  1984年   37篇
  1983年   35篇
  1982年   22篇
  1981年   13篇
  1980年   15篇
  1979年   28篇
  1978年   16篇
  1977年   12篇
  1974年   14篇
  1973年   17篇
  1969年   13篇
排序方式: 共有4267条查询结果,搜索用时 10 毫秒
41.
M Tanaka  S Ikeda  H Yoshimoto 《Surgery》1983,93(2):264-267
Biliary "sump" syndrome is a rare but embarrassing problem after side-to-side choledochojejunostomy or choledochoduodenostomy. Four patients with they syndrome treated nonoperatively by endoscopic sphincterotomy are described. Three of these had had choledochojejunostomy previously and the other inadvertent choledochoduodenostomy at prior common duct exploration. Cholangitic symptoms or biliary obstruction disappeared and the patients have been well for periods ranging from 2 to 5.5 years. Endoscopic sphincterotomy can eliminate the stasis area of the common duct distal to the lateral anastomosis, obviating relaparotomy, and may deserve first consideration in patients with the sump syndrome.  相似文献   
42.
AIM: Large multicenter, randomized trials have revealed the advantages of using tamoxifen for 5 years vs 2 years in breast cancer patients. The aim of this report is to confirm the optimal duration of tamoxifen administration in a study of Japanese breast cancer patients. METHODS: Japanese post-menopausal estrogen receptor-positive breast cancer patients treated with mastectomy were randomly assigned to either a 5-year or 2-year course of tamoxifen. The primary endpoint was disease-free survival, with secondary endpoints of overall survival and a reduction in the development of metachronous contra-lateral breast cancer. RESULTS: A total of 256 breast cancer patients were randomized to a 5-year or 2-year tamoxifen administration group. After a median follow-up time of 81 months, there were no significant differences seen in terms of disease-free or overall survival (p=0.65 and 0.56, respectively). Furthermore, the impact of the 5-year use of tamoxifen on the development of contra-lateral breast cancer did not reach statistical significance (p=0.0511). However, 5-year tamoxifen use was closely associated with gynaecological complications (p=0.0081). CONCLUSION: We could not show a beneficial effect of using tamoxifen for 5 years over 2 years in Japanese estrogen receptor-positive patients. This is likely due to the small number of patients enrolled in our study; however, racial disparity may influence this result. A reevaluation is necessary to study the advantages of the 5-year use of tamoxifen in the Japanese racial subgroup.  相似文献   
43.
44.
To clarify the effect of collagen addition to transplanted adipose tissue on angiogenesis, cell proliferation and tissue remodelling process and reveal whether collagen addition contributes to improving transplanted adipose tissue engraftment in rats. Adipose tissue was harvested from the inguinal and injected into the back of the rat, in addition to collagen. Engraftment tissue was harvested, semi‐quantitatively evaluated and underwent haematoxylin and eosin or Perilipin staining. Moreover, we evaluated viable adipocyte counts and neovascularisation. Macrophages were evaluated using flow cytometry, and the adiponectin or vascular endothelial growth factor (VEGF) mRNA was detected using real‐time polymerase chain reaction. By collagen addition to transplanted adipose tissue, higher engraftment rate semi‐quantitatively and a greater number of new blood vessels histologically were identified. Perilipin staining revealed a higher adipocyte number. The total cell, M1 macrophage and M2 macrophage count were higher. There was increased adiponectin mRNA significantly at week 4 compared to that at week 1 after transplantation. Note that the expression levels of VEGF mRNA increased. In rats, adding collagen enhanced cell proliferation, induced M2 macrophages, which are involved in wound healing, and promoted adipocytes and neovascularisation. Therefore, collagen addition to transplanted adipose tissue could increase the engraftment rate of adipose tissue.  相似文献   
45.
Simple and rapid analysis of aristolochic acid (AA) in crude drugs and Kampo extracts using a solid-phase extraction method and HPLC-PDA analysis was investigated. Extraction of AA from samples was accomplished by adding methanol containing 1% ammonia. The addition of ammonia ionized the AA of acidic substances so that they adhered to an acrylamide copolymer of a strong anion exchange resin (Sep-Pak QMA) coupled to diol silica easily. Furthermore, a mixture of acetonitrile–water–phosphoric acid (75:25:2, v/v) was effective in isolating AA from its carrier. Since almost all interfering peaks originating from contaminants in crude drugs and Kampo extract formulations could be removed, a satisfactory HPLC chromatogram of AA was obtained. A good result was also obtained when Aristolochiaceae and crude drugs containing AA were tested. Particularly in the case of the medicinal parts of Asarum, several interfering peaks and a ghost peak detected near the AA peak were eliminated. The AA contents of two Kampo extract formulations, tokishigyakukagoshuyushokyoto and ryutanshakanto, were calculated by HPLC analysis. The AA content (the sum of AA-I and AA-II) was 1.25–6.13 mg per daily dose. From an additional recovery experiment for Kampo formulations, high recovery rates of AA were obtained. Neither LC/MS nor special instrumentation was necessary. Our results suggest that this simple, quick, and sensitive analytical method to detect AA in crude drugs and Kampo extract formulations would be valuable in safety inspections of AA in crude drugs and their products.  相似文献   
46.
A case of lithium intoxication with downbeat vertical nystagmus   总被引:1,自引:0,他引:1  
Lithium carbonate has recently been used in the treatment of manic diseases. However, since the marginal range between therapeutic and toxic doses is very narrow, close attention should be paid to the development of adverse reactions in its application. Lithium intoxication is manifested by neurological symptoms. Neurotological tests were performed on a patient with lithium intoxication that occurred in the course of psychiatric treatment of mania. The observed sequelae included marked downbeat vertical nystagmus and truncal ataxia. The main lesions in the present case were considered to be located in the cerebellum. Close observation, including neurotological tests, is of greatest importance because in cases of lithium intoxication the development of cerebellar as well as brainstem disorders must not be overlooked.  相似文献   
47.
In Japan, day surgery for breast cancer usually means partial mastectomy without axillary dissection for small carcinoma under local anesthesia in the outpatient clinic. If histopathological examination of the specimens by serial section reveals that the cancer is noninvasive and completely resected with negative surgical margins, no additional surgery under general anesthesia is needed, and the patient does not require hospitalization. We call this procedure "probe lumpectomy". From 1991 to 1998, 169 patients underwent probe lumpectomy in our institution, and there were no major complications. Of these 169 patients, 64 did not require hospitalization. Ipsilateral breast cancer was observed in two patients, and these tumors were diagnosed not as recurrence but as second primary cancers. No distant metastases were observed. As sentinel node biopsy, which is not always easy under local anesthesia, becomes more common, the indications for day surgery or short-stay surgery will expand. As breast cancer is a malignant disease, informed consent and careful follow-up are needed if the treatment is completed only in the outpatient clinic.  相似文献   
48.
IntroductionDigitized assessment of the degree of consciousness is a universal challenge in emergency departments (EDs) and intensive care units (ICUs). The middle latency auditory-evoked potential index (MLAEPi) monitor aepEX plus (Audiomex, Glasgow, Scotland, UK) is the first mobile middle latency auditory-evoked potential monitor. We speculated that the initial MLAEPi determined on arrival at EDs could indicate cerebral function and predict the degree of consciousness of comatose patients.MethodsWe used MLAEPi-related data from 50 comatose patients with disturbance of consciousness (DOC), 50 patients with cardiopulmonary arrest (CPA), and 50 healthy volunteers (control). Comatose patients were defined as those with an initial Glasgow Coma Scale score of 8 or less. The CPA group consisted of patients who arrived at EDs without restoration of spontaneous circulation. Among the patients with DOC who underwent sedation at EDs, the change in the MLAEPi was evaluated between arrival at the ED and ICU admission.ResultsThe initial MLAEPi was significantly lower in the DOC group than in the control group but significantly higher in the DOC group than in the CPA group. Among the comatose patients, the receiver operating characteristic curve for the initial MLAEPi showed an area under the curve of 0.93 (P < .01) for the DOC group. Thirty patients with DOC underwent sedation at EDs, and the initial MLAEPi was significantly higher than those at other periods during emergency care.ConclusionThe MLAEPi (simple numerical value) may be used to evaluate the degree of consciousness in comatose patients while performing emergency care in EDs.  相似文献   
49.
We report a case of infectious endocarditis in a 77-year-old woman who was undergoing maintenance hemodialysis therapy, and who was also having a prosthetic aortic valve replacement. The disease resulted from a local skin infection at the needle puncture site of the arteriovenous fistula. Ampicillin-resistant Staphylococcus aureus was the causal organism. Surgical treatment could not be performed because of associated intracranial hemorrhage due to septic embolism. In spite of intensive treatment with several antibiotics, a ventricular septal abscess just beneath the prosthetic aortic valve progressed to form a ventricular septal fistula. The resultant intracardiac left-to-right shunt led to refractory congestive heart failure. The patient finally died of heart failure. The formation of a ventricular septal fistula is considered to be a rare and extraordinary complication of infectious endocarditis in a hemodialysis patient with aortic valve replacement. Received: July 25, 2001 / Accepted: November 3, 2001  相似文献   
50.
To determine the role of percutaneous vertebroplasty (PVP) in bone formation and the union of vertebral pseudarthrosis, we analyzed 14 patients with an average follow-up duration of 21 months. Evaluation methods included back pain (visual analog scale: VAS), wedge angle, dynamic mobility, radiographic remodeling including callus and spur formation, and union status. The Student's t test was used for statistical analysis and a probability of less than 0.05 was determined as a significant difference. Back pain improved in all 14 patients with a VAS score of 57.8 ± 23.5 mm (average ± standard deviation) preoperatively and 14.7 ± 16.4 mm at the final follow-up (P < 0.001). The wedge angle decreased from 21.6° ± 8.3° (average ± standard deviation) preoperatively to 13.2° ± 6.9° at the final follow-up (P < 0.001). Callus formation was seen in four patients. Bony spurs were seen in the affected vertebra in preoperative radiographs in all patients, and were further developed to a solidified form during follow up after PVP. Dynamic mobility of the affected vertebrae was 6.9 ± 2.9 mm preoperatively, which decreased to 1.1° ± 0.7° at the final follow-up (P < 0.001). Notably, all patients showed the dynamic vertebral mobility of 2 mm or less. Nevertheless, only two patients exhibited the dynamic vertebral mobility of 0 mm at the final follow-up, which is referred to as bone union. These findings indicate that PVP serves as a mechanical stabilizer for vertebral pseudarthrosis, which leads to immediate pain relief and segmental bony responses.  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