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   2795篇
  免费   162篇
  国内免费   10篇
耳鼻咽喉   60篇
儿科学   150篇
妇产科学   69篇
基础医学   335篇
口腔科学   86篇
临床医学   204篇
内科学   618篇
皮肤病学   53篇
神经病学   233篇
特种医学   85篇
外科学   453篇
综合类   39篇
一般理论   1篇
预防医学   207篇
眼科学   73篇
药学   152篇
肿瘤学   149篇
  2024年   4篇
  2023年   32篇
  2022年   40篇
  2021年   81篇
  2020年   40篇
  2019年   81篇
  2018年   145篇
  2017年   86篇
  2016年   104篇
  2015年   101篇
  2014年   159篇
  2013年   181篇
  2012年   240篇
  2011年   205篇
  2010年   107篇
  2009年   83篇
  2008年   166篇
  2007年   147篇
  2006年   150篇
  2005年   155篇
  2004年   116篇
  2003年   117篇
  2002年   116篇
  2001年   43篇
  2000年   47篇
  1999年   54篇
  1998年   3篇
  1997年   8篇
  1996年   5篇
  1995年   3篇
  1994年   3篇
  1993年   7篇
  1992年   17篇
  1991年   17篇
  1990年   18篇
  1989年   10篇
  1988年   8篇
  1987年   13篇
  1986年   12篇
  1985年   7篇
  1984年   3篇
  1983年   4篇
  1977年   3篇
  1975年   3篇
  1973年   4篇
  1971年   2篇
  1968年   3篇
  1966年   3篇
  1965年   1篇
  1962年   1篇
排序方式: 共有2967条查询结果,搜索用时 0 毫秒
11.

Background

Hereditary angioedema (HAE) attacks can be provoked with psychological factors. The aim of this study was to assess the effects of anxiety, depression and stress related to COVID-19 pandemic on disease activity of HAE patients during the quarantine period (QP) and the return to normal period (RTNP).

Methods

This study was conducted between March 2020 and September 2020 in four allergy centres. Demographic, clinical features and mental health status were evaluated in QP (from March to the beginning of June) and RTNP (from June to the beginning of September) applied by the government. The 10-point visual analogue scale (VAS10) was used to define the severity of HAE attacks. Depression, Anxiety and Stress Scales-21 (DASS-21) and Fear of COVID-19 (FC-19) scale were performed to assess mental health status.

Results

139 HAE patients were included in the study. In QP, median attack numbers and median VAS10 scores were 5 (min-max: 0–45) and 6 (min-max: 0–10), respectively. HAE attack numbers, DASS-21 stress, anxiety, depression and total DASS-21 scores, and FC-19 scores were higher in QP than RTNP (p = 0.001, p < 0.001, p = 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). However, there was no difference in attack severity scores between the two periods (p > 0.05).

Conclusions

This study revealed that the restriction measures during COVID-19 outbreak cause an increase in the number of HAE attacks in relation to anxiety, depression, stress and fear of COVID-19 pandemic. Therefore, it is important to provide psychological support to HAE patients during the pandemic.
  相似文献   
12.
Summary Since the application of low doses of IFN-alpha is necessary to maintain remissions in Hairy Cell Leukemia (HCL) it is of interest whether peripheral blood mononuclear cells (MNC) of HCL patients can be induced in vitro to produce IFN-alpha. 9 patients suffering from advanced HCL were included in the study. The diagnoses were confirmed by characteristic findings in peripheral blood and bone marrow biopsies. For IFN treatment we initially used natural IFN-alpha (Bioferon) and switched later to recombinant IFN-alpha2 (Boehringer). MNC of 5 patients before IFN therapy and of 6 patients during IFN therapy (2–47 weeks) were induced by phythemagglutinin (PHA), Corynebacterium parvum (C.p.), and sendai virus (SV). PHA is known to induce IFN-gamma. Both, C.p. and SV induced IFN-alpha but no IFN-gamma in MNC of healthy controls and of IFN treated breast cancer patients. In HCL patients normal antiviral activities could be induced by PHA. Zero or only low antiviral activities could be induced in MNC from 9 patients tested on 22 occasions. It is concluded that MNC from patients with advanced HCL can be induced to produce IFN-gamma but no IFN-alpha. Since IFN-alpha but not IFN-gamma is produced by monocytes it is likely that reduced numbers of monocytes which were found in our HCL patients before and during IFN treatment account for the described deficiency of IFN-alpha production.  相似文献   
13.
International Urology and Nephrology - The number of kidney biopsies (KB) performed in elderly patients has been increasing. Safety and usefulness of elderly KB have been well established, whereas...  相似文献   
14.
In this study, we evaluated the role of the Prostate Imaging–Reporting and Data System (PI-RADS) classification of multiparametric magnetic resonance imaging (mpMRI) to determine the likelihood of prostate cancer (PCa) in patients with haemospermia. Fifty-one patients presenting with haemospermia between 2018 and 2020 were included in this retrospective study. Forty-two of the patients (82.4%) were over 40 years, and the median prostate-specific antigen (PSA) level was 1.4 ng/ml. Fourteen of the patients (27.5%) had recurrent haemospermia. All patients underwent mpMRI, and assessments were classified according to PI-RADS v2. The mpMRI revealed PI-RADS one to four lesions in 10 (19.6%), 30 (58.8%), 6 (11.8%) and 5 (9.8%) patients respectively. One patient with PI-RADS 3 and five with PI-RADS 4 lesions underwent cognitive fusion prostate biopsy depending on MRI findings, and two patients with PI-RADS 4 lesions were diagnosed with PCa. Patients with haemospermia and risk factors, that is aged over 40 years, a high PSA level or familial history of PCa, need a more thorough evaluation with mpMRI.  相似文献   
15.
The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.  相似文献   
16.
Aránzazu Caballero-Marcos  Magdalena Salcedo  Roberto Alonso-Fernández  Manuel Rodríguez-Perálvarez  María Olmedo  Javier Graus Morales  Valentín Cuervas-Mons  Alba Cachero  Carmelo Loinaz-Segurola  Mercedes Iñarrairaegui  Lluís Castells  Sonia Pascual  Carmen Vinaixa-Aunés  Rocío González-Grande  Alejandra Otero  Santiago Tomé  Javier Tejedor-Tejada  José María Álamo-Martínez  Luisa González-Diéguez  Flor Nogueras-Lopez  Gerardo Blanco-Fernández  Gema Muñoz-Bartolo  Francisco Javier Bustamante  Emilio Fábrega  Mario Romero-Cristóbal  Rosa Martin-Mateos  Julia Del Rio-Izquierdo  Ana Arias-Milla  Laura Calatayud  Alberto A. Marcacuzco-Quinto  Víctor Fernández-Alonso  Concepción Gómez-Gavara  Jordi Colmenero  Patricia Muñoz  José A. Pons  the Spanish Society of Liver Transplantation 《American journal of transplantation》2021,21(8):2876-2884
The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, < .001) and at 6 months (63.4% vs. 90.1%, < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (= .001) and 6 months (< .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline.  相似文献   
17.
18.
Interferon (IFN) alpha is now used in the treatment of some malignant diseases and chronic viral hepatitis. There have been several reports of development of autoantibodies and autoimmune diseases or the deterioration of preexisting disorders in patients under treatment. We enclose a case of myasthenia gravis (MG) which developed after six weeks of treatment as fluctuating bilateral ptosis, intermittent diplopia, and mild weakness of limb and neck muscles. A test dose of edrophonium chloride was administered, resulting in improved muscle strength. Elevated anti acetylcholine receptor (AChR) antibody titer was found. Single fiber electromyography showed an increased jitter from extensor digitorum communis, frequently accompanied by transmission blocking. Repetitive electric 3 Hz stimulation of the abductor pollicis brevis muscle, revealed an abnormal decrement of 28% in compound motor action potential. Myasthenia gravis was diagnosed and the patient was given pyridostigmine, immunoglobulines and prednisone with benefit. Six months latter he developed an acute myasthenic crisis with severe respiratory failure and high anti AChR antibody titer. IFN-alpha can induce MG or simply manifests a preexisting subclinical disease, but otherwise its therapeutic efficacy in MG has been shown in experimental and clinical studies. Autoimmune mechanisms, as the release of different cytokines as IFN, by immunocompetent cells, may be involved in the pathogenesis of both MG and chronic active hepatitis. Autoantibody production against postsynaptic membrane structures by IFN-alpha could be the underlying pathophysiology.  相似文献   
19.
J Arányi  J Radó 《Orvosi hetilap》1992,133(31):1965-1967
A medical student sportsman had been admitted to the hospital because of weakness and painful swelling of the muscle as well as dark urine appearing after carrying out an excessive body-building performance. On the basis of indirect evidences pigmenturia "per exclusionem" was a manifestation of urinary myoglobin excretion. The development of an "acute exertional rhabdomyolysis" was confirmed by the increased serum enzyme levels and myoglobinuria. The outcome of the illness was fortunate, as acute renal failure could be avoided. On the basis of survey of the literature it can be stated, that this presumably frequently occurring, but rarely recognized disease may have importance from clinical, sporting medicine and pathophysiological point of view.  相似文献   
20.
BACKGROUND: Coagulase negative staphylococci (CoNS) have been recognized as important pathogens in nosocomial infections, especially in connection with implanted foreign materials. In cardiac operation they are among the most common pathogens isolated from infected sternal wounds. The definition of the infection is very important. In this study we focus on deep postoperative chest infections. METHODS: By studying 33 infected patients retrospectively and comparing them to 33 matched uninfected controls, we studied the characteristics and costs of the infections. RESULTS: Typical for these infections is the late and insidious onset, and that the infections initially give only minor symptoms such as pain, redness, and serous secretion. We found the following risk factors for infection: number of preoperative days in a hospital, the total length of the operation, and if the patient had undergone an early reoperation due to causes other than infection. This kind of infection more than doubled the hospital costs for the patients affected. CONCLUSIONS: Coagulase negative staphylococci are the most important pathogens in deep postoperative infections in this material. They cause infections that are difficult to recognize since they give only discrete symptoms and start well after the patients leave the hospital. The risk factors for patients with CoNS infections are mostly associated with a long exposure to the hospital environment. The treatment is often difficult and costly because of multiresistant bacteria and frequent need for repeated surgical revisions.  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