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   6515篇
  免费   517篇
  国内免费   176篇
耳鼻咽喉   7篇
儿科学   720篇
妇产科学   124篇
基础医学   451篇
口腔科学   2篇
临床医学   667篇
内科学   1068篇
皮肤病学   7篇
神经病学   1376篇
特种医学   305篇
外科学   202篇
综合类   1101篇
预防医学   421篇
眼科学   19篇
药学   510篇
  4篇
中国医学   161篇
肿瘤学   63篇
  2023年   101篇
  2022年   155篇
  2021年   283篇
  2020年   261篇
  2019年   248篇
  2018年   233篇
  2017年   220篇
  2016年   272篇
  2015年   251篇
  2014年   472篇
  2013年   439篇
  2012年   429篇
  2011年   451篇
  2010年   319篇
  2009年   337篇
  2008年   298篇
  2007年   341篇
  2006年   321篇
  2005年   223篇
  2004年   180篇
  2003年   171篇
  2002年   168篇
  2001年   148篇
  2000年   116篇
  1999年   84篇
  1998年   76篇
  1997年   72篇
  1996年   55篇
  1995年   46篇
  1994年   54篇
  1993年   46篇
  1992年   38篇
  1991年   41篇
  1990年   22篇
  1989年   30篇
  1988年   24篇
  1987年   18篇
  1986年   30篇
  1985年   28篇
  1984年   21篇
  1983年   10篇
  1982年   10篇
  1981年   14篇
  1980年   14篇
  1979年   6篇
  1978年   5篇
  1977年   6篇
  1975年   4篇
  1974年   3篇
  1968年   4篇
排序方式: 共有7208条查询结果,搜索用时 15 毫秒
1.
Introduction and aimsCirrhosis is the common outcome of liver diseases. It can be decompensated and lead to the development of complications, such as encephalopathy. Hyperammonemia that develops due to liver dysfunction is etiopathologically related to hepatic encephalopathy. Caffeine increases the activity of the urea cycle in the liver, augmenting ammonia degradation. By antagonizing adenosine receptors, it also has a hepatoprotective effect, impeding the formation of fibrosis, as well as having a stimulating effect on the central nervous system. The present study analyzed the effects of caffeine on the progression of cholestatic liver fibrosis and hepatic encephalopathy.Materials and methodsAn experimental model of cholestatic liver fibrosis, through common bile duct ligature, and of hepatic encephalopathy, through the administration of a high-protein diet, was constructed. Male Wistar rats (n = 32) were equally divided into 4 groups. The experiment lasted 28 days, with the administration of 50 mg/kg/day of caffeine. Laboratory tests, histologic analyses of the liver and encephalon, open field tests (OFTs), and daily behavioral analyses were carried out.ResultsThe ligated animals treated with caffeine had lower mean transaminase levels and improved histologic aspects of the liver and encephalon. The untreated ligated animals were clearly lethargic and apathetic at the last week of the experiment, confirmed by reduced exploratory activity during the OFT.ConclusionCaffeine improved the microarchitecture of the liver and encephalon of the cirrhotic animals and prevented the decrease in exploratory behavior of the animals during the OFT.  相似文献   
2.
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored.  相似文献   
3.
Psychosis is a common and intractable disorder of hospitalization, especially in patients hospitalized in Intensive Care Unit (ICU). Along with the widely use of multiple antibiotics in community-acquired infection and hospital-acquired infection, the occurrence of antibiotic-associated neurological disorders has become more frequently. However, antibiotic neurotoxicity is often overlooked or misinterpreted. In this review, we summarized the neurological disorders caused by antibacterial agent usage and firstly systematically formulated the pathogenesis of antibiotic-associated neurotoxic reactions. Precautions of the complications are critical in preventing serious clinical outcome as the inducement is curable. Regular neurological physical examination, electroencephalogram (EEG) examination, lumbar puncture and therapeutic drug monitoring closely are essential for early diagnosis and differential diagnosis.  相似文献   
4.
5.
PurposeTo assess the critical role of transjugular intrahepatic portosystemic shunt (TIPS) in the management of Budd-Chiari syndrome (BCS), as the data with respect to the safety and outcome of TIPS in patients with BCS are scarce because of the rarity of the disease.Materials and MethodsA comprehensive search of literature of various databases from 2000 to October 2021 was conducted for studies evaluating the outcome of TIPS in patients with BCS. The primary outcomes of the analysis were technical and clinical success, adverse events and mortality associated with TIPS, dysfunction of TIPS, need for TIPS revision, need for liver transplantation (LT), and 1-year survival.ResultsA total of 33 studies (1,395 patients) were included in this meta-analysis. The pooled rates and 95% confidence intervals of various outcomes were 98.6% (97.6–99.7) for technical success, 90.3% (86.0–94.6) for clinical success, 10.0% (6.5–13.6) for major adverse events, 0.5% (0.2–1.0) for TIPS-related mortality, 11.6% (7.8–15.4) for post-TIPS hepatic encephalopathy (HE), 40.1% (32.5–47.7) for TIPS dysfunction, 8.6% (4.9–12.4) for the need for TIPS revision, 4.5% (2.8–6.2) for the need for LT, and 94.6% (93.1–96.1) for 1-year survival. Publication bias was seen with all outcomes except for post-TIPS HE, TIPS dysfunction, and the need for LT.ConclusionsThe existing literature supports the feasibility, safety, and efficacy of TIPS in the treatment of BCS. Deciding the optimal timing of TIPS in BCS needs further studies.  相似文献   
6.
PurposeTo assess clinical outcomes and patency after transjugular intrahepatic portosystemic shunt (TIPS) reduction for overshunting adverse events.Materials and MethodsThis multicenter, retrospective observational study included 33 patients (male-to-female ratio, 20:13; mean age, 59 years; mean Model for End-Stage Liver Disease [MELD] score, 15) who underwent TIPS reduction between 2007 and 2020. Procedure indications included medically refractory hepatic encephalopathy (HE) (85%), post-TIPS hepatic insufficiency (HI) (12%), and heart failure (3%). The measured outcomes included improvement in HE (classified using the West Haven system) and HI, patency of reduced TIPS, and transplant-free survival (TFS).ResultsTIPS reductions were successfully performed using parallel stent (94%) or other (6%) techniques at a median of 120 days after TIPS creation (HE, median, 164 days; HI, median, 5 days). The portosystemic pressure gradient increased from a mean of 10 to 17 mm Hg (P < .001). The overall HE rate after TIPS reduction was 54%; HE was persistent, improved, and resolved in 21%, 32%, and 46% cases, respectively. In patients with HI, the MELD score increased from a mean of 22 before TIPS to 34 after TIPS (P = .061), but without improvement (0%) in HI after TIPS reduction (mean MELD score, 30; P = .266). Recurrent ascites occurred in 14% of the patients. The median shunt patency was 961 days (95% confidence interval, 476–1,447). The 30-day, 6-month, 1-year, and 3-year shunt patency rates were 92%, 81%, 74%, and 37%, respectively. The median TFS was not reached. The 30-day, 6-month, 1-year, and 3-year survival rates were 97%, 90%, 81%, and 60%, respectively.ConclusionsAlthough TIPS reduction may be an effective and durable approach to treat post-TIPS medically refractory HE, shunt reduction may not achieve meaningful benefit for HI.  相似文献   
7.
Glycine encephalopathy with normal serum glycine (MIM #617301), also known as GLYT1 encephalopathy, is an extremely rare disorder caused by biallelic variants in SLC6A9 and characterised by facial dysmorphic features, skeletal findings including contractures, knee hyperextension, and joint dislocations and seizures. To date, only ten patients from five families have been reported and only two of them could survive until childhood. In this study, we report on a consanguineous Turkish couple with a history of six pregnancies with three habitual abortions and three postpartum exitus. While in three pregnancies the babies were born prematurely at 32nd gestational week by emergency ceserean section due to hydrops and fetal distress, the other pregnancy was medically terminated at 16th gestational week due to absent fetal heart activity. The product of all these three pregnancies exhibited similar phenotype including short neck, thoracic kyphosis, hypertrichosis, joint contractures and dislocations, hypertonia, knee hyperextension and facial dysmorphic features. Trio exome sequencing was performed prenatally during the last pregnancy and a novel VUS variant in SLC6A9 and a likely pathogenic variant in MTOR gene were detected. DNA isolation was performed from frozen muscle and adrenal tissue of previously autopsied fetuses with similar clinical features, and the same variants were confirmed in both of them. Our data suggest that SLC6A9 and MTOR variants may be responsible for this extremely lethal phenotype in this family.  相似文献   
8.
9.
Traumatic brain injury (TBI) is caused by a head impact with a force exceeding regular exposure from normal body movement which the brain normally can accommodate. People affected include, but are not restricted to, sport athletes in American football, ice hockey, boxing as well as military personnel. Both single and repetitive exposures may affect the brain acutely and can lead to chronic neurodegenerative changes including chronic traumatic encephalopathy associated with the development of dementia. The changes in the brain following TBI include neuroinflammation, white matter lesions, and axonal damage as well as hyperphosphorylation and aggregation of tau protein. Even though the human brain gross anatomy is different from rodents implicating different energy transfer upon impact, especially rotational forces, animal models of TBI are important tools to investigate the changes that occur upon TBI at molecular and cellular levels. Importantly, such models may help to increase the knowledge of how the pathologies develop, including the spreading of tau pathologies, and how to diagnose the severity of the TBI in the clinic. In addition, animal models are helpful in the development of novel biomarkers and can also be used to test potential disease‐modifying compounds in a preclinical setting.  相似文献   
10.
Heat stress is a recognized occupational hazard in aluminum smelter pot rooms. This is the report of an unusual and complex case of heat-related illness in an aluminum smelter worker. The 34-year-old male US worker developed life-threatening heat-related illness in August 2018, on his first day back at work after a 7-day absence. The worker initially presented with bilateral hand then all-extremity cramping followed some hours later by a generalized seizure and acute mental status changes, including combativeness. Emergency room evaluation identified a serum sodium level of 114 mmol/L. Acute liver and kidney injury ensued along with profound rhabdomyolysis, with peak total creatinine phosphokinase level reaching over 125 000 units/L at 3 days post incident. Initial ventilatory support, careful fluid resuscitation, and electrolyte management were provided. Metabolic encephalopathy resolved. Complications included sepsis. After 5 days in the intensive care unit and eight additional days of inpatient management, observation, and the initiation of rehabilitation, the worker was discharged. Residual effects include polyneuropathy of upper and lower extremities and the postdischarge magnetic resonance imaging finding of a cerebellar lesion. Prevailing considerations in the differential diagnosis included exertional heat stroke and/or exertion-associated hyponatremia with encephalopathy.  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