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   3922篇
  免费   177篇
  国内免费   23篇
耳鼻咽喉   78篇
儿科学   34篇
妇产科学   86篇
基础医学   723篇
口腔科学   64篇
临床医学   316篇
内科学   877篇
皮肤病学   70篇
神经病学   240篇
特种医学   215篇
外科学   424篇
综合类   18篇
一般理论   4篇
预防医学   164篇
眼科学   19篇
药学   439篇
中国医学   64篇
肿瘤学   287篇
  2023年   21篇
  2022年   61篇
  2021年   133篇
  2020年   69篇
  2019年   82篇
  2018年   102篇
  2017年   69篇
  2016年   116篇
  2015年   179篇
  2014年   193篇
  2013年   228篇
  2012年   364篇
  2011年   334篇
  2010年   210篇
  2009年   177篇
  2008年   241篇
  2007年   256篇
  2006年   225篇
  2005年   213篇
  2004年   143篇
  2003年   132篇
  2002年   93篇
  2001年   98篇
  2000年   69篇
  1999年   69篇
  1998年   28篇
  1997年   15篇
  1996年   25篇
  1995年   15篇
  1994年   10篇
  1993年   9篇
  1992年   21篇
  1991年   11篇
  1990年   7篇
  1989年   7篇
  1988年   5篇
  1987年   5篇
  1986年   9篇
  1985年   9篇
  1984年   10篇
  1981年   3篇
  1980年   3篇
  1979年   3篇
  1978年   8篇
  1973年   4篇
  1972年   4篇
  1971年   6篇
  1970年   4篇
  1968年   4篇
  1961年   2篇
排序方式: 共有4122条查询结果,搜索用时 921 毫秒
21.
Spontaneous acute tumor lysis syndrome with advanced gastric cancer   总被引:3,自引:0,他引:3  
Acute tumor lysis syndrome (TLS) occurs frequently in hematologic malignancies such as high-grade lymphomas and acute leukemia, which are rapidly proliferating and chemosensitive tumors. It occurs rarely in solid tumors and has never been reported in gastric adenocarcinoma. Typical biochemical findings of acute tumor lysis syndrome are hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia in patients with a malignancy. Rapid changes of these electrolytes may cause cardiac arrhythmia, seizure, acute renal failure and sudden death. Therefore, as soon as it is detected, it should be taken care of immediately. Until now almost all cases of TLS associated with solid tumor have developed after cytoreductive therapy in chemosensitive tumors. We report here a case of spontaneous acute tumor lysis in a patient of advanced gastric cancer with hepatic metastases and multiple lymphadenopathy. The biochemical finding of TLS improved with the management and tumor burden also showed slight response to the one cycled combination chemotherapy but the patient died of progressive pneumonia.  相似文献   
22.
The available data on the association between micronutrients in the blood and non-alcoholic fatty liver disease (NAFLD) are limited. To investigate the clinical implications of this relationship, we sought to identify the difference in the serum levels of vitamins A and E according to NAFLD status using data from the seventh Korea National Health and Nutrition Examination Survey. In this cross-sectional study of the Korean population, NAFLD and its severity were defined using prediction models. Differences in the prevalence and severity of NAFLD were analyzed according to serum retinol (vitamin A) and alpha (α)-tocopherol (vitamin E) levels. Serum levels of retinol and α-tocopherol were positively correlated with the prevalence of NAFLD. In most prediction models of the NAFLD subjects, serum retinol deficiency was significantly correlated with advanced fibrosis, while serum α-tocopherol levels did not differ between individuals with or without advanced fibrosis. Similar trends were also noted with cholesterol-adjusted levels of α-tocopherol. In summary, while circulating concentrations of retinol and α-tocopherol were positively associated with the presence of NAFLD, advanced liver fibrosis was only correlated with serum retinol levels. Our findings could provide insight into NAFLD patient care at a micronutrient level.  相似文献   
23.
International Urology and Nephrology - To date, several studies have reported inconsistent findings regarding the mortality risk faced by living kidney donors and controls. Our study assessed the...  相似文献   
24.
International Urology and Nephrology - Late onset hypogonadism (LOH) is an age-dependent reduction of testosterone associated with alterations of metabolic profile, including glucose control,...  相似文献   
25.
BackgroundWe encountered some cases of early-onset tuberculosis (TB) after liver transplant (LT), leading to further transmission to other immunocompromised patients. Therefore, we investigated the clinical characteristics and risk factors of early-onset TB after LT.MethodsAll adult patients with TB after LT from 1996 to 2019 were retrospectively enrolled. Our hospital did not screen for latent TB infection (LTBI) in LT recipients because of concerns regarding the potential hepatotoxicity of anti-TB medication. Patients were categorized into 2 groups based on the TB onset time after LT: early-onset TB (≤2 months) and late-onset TB (>2 months).ResultsOf 4301 LT recipients, 91 patients developed TB after LT (2.1%). The median time from LT to TB development was 9.4 months. Of these 91 patients, 11 were classified as having early-onset TB (12.1%). Patients with early-onset TB had a greater pretransplant TB history than patients with late-onset TB (36.4% vs 11.3%, P = .048).ConclusionThis unusual early-onset TB was more common in patients with a pretransplant TB history, suggesting the possibility of missed TB or full manifestation of the indolent course of TB after LT. Therefore, LT recipients with a pretransplant TB history should undergo thorough screening for active TB and consider prophylaxis.  相似文献   
26.
The effects of inhibiting monoamine oxidase (MAO) A and B on metabolism and uptake of serotonin (5-HT) in serotonergic synaptosomes were studied. To avoid contamination by extrasynaptosomal MAO, synaptosomes were separated from other components of rat brains by discontinuous sucrose density gradient centrifugation. Kinetic analysis of 5-HT uptake demonstrated that 5-HT was selectively transported into serotonergic synaptosomes through the high affinity 5-HT uptake process. Selectivity of the uptake and subsequent deamination of 5-HT within serotonergic synaptosomes were confirmed using selective and non-selective 5-HT and norepinephrine (NE) uptake inhibitors. MAO inhibitor analysis of 5-HT deamination occurring within serotonergic synaptosomes indicated that, at physiologically relevant concentrations of 5-HT, MAO A deaminates 5-HT, maintaining a low cytoplasmic concentration of 5-HT. When the cytoplasmic concentration of 5-HT is increased above physiologically relevant levels by the inhibition of MAO A, MAO B becomes active. [( 14)C] 5-HT uptake into synaptosomes was reduced by decreasing the V( max) of [(14)C] 5-HT uptake. One mechanism for a decrease in the V(max) could be the increase in the cytoplasmic concentration of 5-HT.  相似文献   
27.
28.
BACKGROUND: Stage II non-small-cell lung cancer is regarded as one of the early lung cancers. Although resection, including the mediastinal lymph nodes, is currently regarded as the standard treatment, the survival rate of this disease is not encouraging. It is well known that the most common causes of death are locoregional recurrences or distant metastases, or both. However, the best adjuvant treatment to improve survival is as controversial an issue as ever. METHODS: This study was designed as a randomized, blinded, two-armed study with operation and adjuvant radiotherapy in one arm, versus operation and adjuvant mitomycin C (10 mg/m2), vinblastine (6 mg/m2), and cisplatin (100 mg/m2) (MVP) chemotherapy in the other arm. We assigned 57 resected patients with pathologic proven stage II non-small cell lung cancer to the groups according to our eligibility criteria. RESULTS: The most common pattern of recurrence was distant metastases, and nearly all the recurrences (17 of 18 patients) in both groups were found within 2 years after operation. The rates of the locoregional and distant metastases were 3.6% and 46.4% in the adjuvant radiotherapy group and 6.9% and 10.3% in the adjuvant chemotherapy group (p = 0.018). The 5-year disease-free survival rates were 52.0% in the adjuvant radiotherapy group and 74.0% in the adjuvant chemotherapy group (p = 0.16, log-rank test). The 2-year, 5-year, and 6-year survival portions were 60.3%, 56.5%, and 28.3% in the adjuvant radiotherapy group, and 82.8%, 70.1%, and 60.1% in the adjuvant chemotherapy group (p = 0.01, p = 0.17, and p = 0.03, Z-test). The difference of the actuarial survival between these two groups was somewhat significant (p = 0.09, log-rank test). CONCLUSIONS: Our results suggest that the addition of adjuvant MVP chemotherapy may reduce the distant metastasis rates and prolong the survival of the surgically resected stage II non-small-cell lung cancer patients.  相似文献   
29.
PURPOSE: The aim of this study was to examine the efficacy of the antirefluxing, mucosal-flap valve (AMFV) for biliary drainage relative to technical feasibility, surgical complications, and incidence of ascending cholangitis (AC). METHODS: Twenty-seven infants requiring biliary tract reconstruction underwent valve construction. Twenty biliary atresia (BA) patients received the Kasai procedure, and 7 choledochal cyst (CC) infants had cystectomy and hepatoenterostomy. A retrospective review of all patients was performed including radiographic evaluation of the current valve function in 10 patients. RESULTS: Construction was successful in all cases, and no morbidity was incurred by incorporation of the valve. Of 7 CC patients, there have been no known episodes of AC with mean follow-up of 4.4+/-4.2 years. Of 20 BA patients, there have been 5 deaths (25%), 7 liver transplants (35%), 2 (10%) lost to follow-up, and 6 (30%) survivors. Nine BA patients (45%) have had AC, with patients in all 4 outcome categories represented. Ten patients (5 CC and 5 BA) have been evaluated with barium small bowel radiographs, with no reflux to the liver hilum in all cases. CONCLUSIONS: The AMFV has caused no morbidity and continues to prevent reflux to the liver hilum. Despite functioning as designed, it does not appear to influence the occurrence of AC. Because CC patients had no AC, we feel that infection is related to the underlying atresia rather than to reflux.  相似文献   
30.
Internal carotid artery or ophthalmic artery occlusions are devastating ophthalmological events which lead to severe impairment of vision. A case of multiple branch retinal artery occlusions in a 63-year-old male with internal carotid artery and ophthalmic artery occlusions on brain angiography is presented. Emboli lodging in branches of the retinal arteries were bright, glistening, yellow or orange in appearance. Such a distinctive ophthalmoscopic appearance led to the diagnosis of cholesterol emboli. Fluorescein and indocyanine green angiography disclosed delayed filling of the retinal vessels and choroid, and showed multiple hypofluorescence distal to the vessels in which the emboli were lodged. At the time of initial examination, the number of emboli lodged in retinal arteries was estimated at more than 20. As time passed, a few of the previous emboli disappeared and new emboli appeared in other sites on fundus examination. We think that the lodging of new emboli in other sites is due to the continued break-up of atheromatous tissue through the collateral circulation associated with the occlusion of the internal carotid and ophthalmic arteries.  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