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51.
Profound disturbances of different elements of the immune system in chronic lymphocytic leukemia (CLL) lead to impaired elimination of allogeneic antigens, like pathogenic microorganisms, and deficient tolerance of self-antigens, which is responsible for autoimmunological disorders. Susceptibility to infections in CLL patients is due to disease-related immunodeficiency, mainly hypogammaglobulinemia, and aggravated by myelo- and immunosuppressive properties of currently used antileukemic drugs, especially alkylating agents and purine analogues. Severe infections occur in the majority of CLL patients, they may be life-threatening and shortening the patients’ survival. They affect most frequently the respiratory system, and are caused mainly by Gram-positive and Gram-negative bacteria and common viruses like Herpes and Varicella-Zoster. In some patients, especially those treated with purine analogues, opportunistic infections can occur. There are no generally admitted guidelines for the prophylaxis of infections. Vaccinations against influenza and encapsulated bacteria, intravenous immunoglobulins and prophylaxis with cotrimoxazol and antiviral drugs for selected patients under purine analogues or alemtuzumab have been proposed. Autoimmune hemolytic anemia (AIHA) due to the production of anti-erythrocyte autoantibodies is the most common autoimmunological complication of CLL, especially in patients with positive direct antiglobulin test (DAT). It can be also triggered by alkylating agents and purine analogues. The treatment of AIHA includes corticosteroids, rituximab, immunosuppressive agents and splenectomy. Autoimmune thrombocytopenia, pure red cell aplasia, autoimmune neutropenia and non-hematological autoimmune manifestations can also occur.  相似文献   
52.
Hyaline fibromatosis syndrome is an autosomal recessive disease caused by mutations in ANTXR2, a gene involved in extracellular matrix homeostasis. Sixty percent of patients carry frameshift mutations at a mutational hotspot in exon 13. We show in patient cells that these mutations lead to low ANTXR2 mRNA and undetectable protein levels. Ectopic expression of the proteins encoded by the mutated genes reveals that a two base insertion leads to the synthesis of a protein that is rapidly targeted to the ER‐associated degradation pathway due to the modified structure of the cytosolic tail, which instead of being hydrophilic and highly disordered as in wild type ANTXR2, is folded and exposes hydrophobic patches. In contrast, one base insertion leads to a truncated protein that properly localizes to the plasma membrane and retains partial function. We next show that targeting the nonsense mediated mRNA decay pathway in patient cells leads to a rescue of ANTXR2 protein in patients carrying one base insertion but not in those carrying two base insertions. This study highlights the importance of in‐depth analysis of the molecular consequences of specific patient mutations, which even when they occur at the same site can have drastically different consequences.  相似文献   
53.
Churg–Strauss syndrome (CSS) is a rare systemic small-vessel vasculitis that develops in the background of bronchial asthma, which is characterized by eosinophilia and eosinophilic infiltration of various tissues. It belongs to the group of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides. The triggering factors and pathogenesis of CSS are still unknown. The possible role of eotaxin-3 and CCR4-related chemokines in selective recruitment of eosinophils to the target tissues in CSS has been recently suggested, but the role of eosinophilic inflammation in the development of vasculitic lesions is not completely understood. From the clinical view, two distinct phenotypes of the disease are slowly emerging depending on the ANCA-positivity status. Glucocorticoids are still the mainstay of treatment; however, data are accumulating regarding the beneficial role of novel immunosuppressants and biologic compounds, especially in patients with poorer prognosis.  相似文献   
54.
Background. Patients with degenerative aortic stenosis (AS) exhibit elevated prevalence of coronary artery disease (CAD) and internal carotid artery stenosis (ICAS). Our aim was to investigate prevalence of significant CAD and ICAS in relation to demographic and cardiovascular risk profile among patients with severe degenerative AS.Methods. We studied 145 consecutive patients (77 men and 68 women) aged 49-91 years (median, 76) with severe degenerative AS who underwent coronary angiography and carotid ultrasonography in our tertiary care center. The patients were divided into two groups according to the presence of either significant CAD (n=86) or ICAS (n=22).Results. The prevalence of significant CAD or ICAS was higher with increasing number of traditional risk factors (hypertension, hypercholesterolemia, diabetes, smoking habit) and decreasing renal function. We found interactions between age and gender in terms of CAD (p=0.01) and ICAS (p=0.06), which was confirmed by multivariate approach. With the reference to men with a below-median age, the prevalence of CAD or ICAS increased in men aged >76 years (89% vs. 55% and 28% vs. 14%, respectively), whereas the respective percentages were lower in older vs. younger women (48% vs. 54% and 7% vs. 17%).Conclusions. In severe degenerative AS gender modulates the association of age with coronary and carotid atherosclerosis with its lower prevalence in women aged >76 years compared to their younger counterparts. This may result from a hypothetical “survival bias”, i.e., an excessive risk of death in very elderly women with severe AS and coexisting relevant coronary or carotid atherosclerosis.  相似文献   
55.
Wozakowska-Kapłon B  Opolski G  Janion M  Kosior D 《Kardiologia polska》2004,61(12):513-21; discussion 522
BACKGROUND: Plasma concentration of atrial natriuretic peptide (ANP) is elevated in patients with atrial fibrillation (AF) and in patients with chronic heart failure (CHF).Aim. To assess ANP level in patients with permanent AF and advanced CHF. METHODS: The study group consisted of 41 patients (27 males, mean age 62+/-8 years) with AF of a mean duration of 8.8 months. Twenty six (63%) patients were in NYHA class II, and 15 (37%) - in NYHA class III or IV. All patients underwent clinical and echocardiographic evaluation as well as ANP plasma concentration assessment. Multiple regression analysis was used to identify factors which determine ANP plasma concentration. RESULTS: Mean ANP plasma concentration was 52.4+/-22.7 pg/ml in the whole study group; 38.6+/-10.8 pg/ml in NYHA class II patients and 74.9+/-18.7 pg/ml in NYHA class III-IV subjects (p<0.0001). Among echocardiographic parameters, patients with NYHA class III or IV had significantly lower left ventricular ejection fraction and greater left atrial volume than patients with NYHA class II (32% versus 56%, p<0.0001 and 101.0+/-23.8 cm(3) versus 83.4+/-16.1 cm(3), p<0.006, respectively). Multiple regression analysis revealed a significant negative correlation between AF duration and ANP level (p=0.0013) in a group of patients with NYHA class III or IV and identified AF duration as an independent predictor of ANP plasma concentration in this group of patients. CONCLUSIONS: ANP plasma concentration in patients with persistent AF and advanced CHF is determined by AF duration - the longer the AF duration the lower the ANP level.  相似文献   
56.
Stem cell localization, conservation, and differentiation isbelieved to occur in niches in the marrow stromal microenvironment. Ourrecent observation that long-term in vitro human hematopoiesis requiresa stromal heparan sulfate proteoglycan (HSPG) led us to hypothesizethat such HSPG may orchestrate the formation of the stem cell niche. Wecompared the structure and function of HS from M2-10B4, ahematopoiesis-supportive cell line, with HS from a nonsupportive cellline, FHS-173-We. Long-term culture-initiating cell (LTC-IC)maintenance was enhanced by PG from supportive cells but not by PG fromnonsupportive cells (P < .005). The supportive HS weresignificantly larger and more highly sulfated than the nonsupportiveHS. Specifically, supportive HS contained higher 6-O-sulfation on theglucosamine residues. In agreement with these observations, purified6-O-sulfated heparin and highly 6-O-sulfated bovine kidney HS similarlymaintained LTC-IC. In contrast, completely desulfated heparin,N-sulfated heparin, and unmodified heparin did not support LTC-ICmaintenance. Moreover, the supportive HS promoted LTC-IC maintenancebut not differentiation of CD34+/HLA-DRcells into colony-forming cells (CFCs) and mature bloodcells. The supportive HS but not the nonsupportive HS bound bothcytokines and matrix components critical for hematopoiesis, includinginterleukin-3 (IL-3), macrophage inflammatory protein-1 (MIP-1),and thrombospondin (TSP). Significantly more CD34+ cellsadhered directly to immobilized O-sulfated heparin than to N-sulfatedor desulfated heparin. Thus, hematopoiesis-supportive stromal HSPGpossessing large, highly 6-O-sulfated HS mediate the juxtaposition ofhematopoietic progenitors with stromal cells, specific growth-promoting(IL-3) and growth-inhibitory (MIP-1 and platelet factor 4 [PF4])cytokines, and extracellular matrix (ECM) proteins such as TSP. Weconclude that the structural specificity of stromal HSPG thatdetermines the selective colocalization of cytokines and ECM componentsleads to the formation of discrete niches, thereby orchestrating thecontrolled growth and differentiation of stem cells. These findings mayhave important implications for ex vivo expansion of and gene transferinto primitive hematopoietic progenitors.  相似文献   
57.
A case of a 58-year-old female patient with unstable angina is presented. Two weeks earlier the patient suffered from acute myocardial infarction treated with thrombolysis. The patient underwent surgical revascularisation which was complicated by acute pulmonary embolism. Repeated surgery and inspection of pulmonary arteries revealed the presence of thrombus which was successfully removed. The post-operative course was uneventful. The causes and treatment of pulmonary embolism complicating coronary artery by-pass grafting are discussed.  相似文献   
58.
Last decade brought great development in the treatment of patients with heart failure (HF). General use of angiotensin-converting-enzyme inhibitors (ACE-I) in patients with asymptomatic left ventricular dysfunction or with HF significantly reduced morbidity and mortality. The aim of this study was to assess how the specialists from Cardiology Department and Gastroenterology Department think that heart failure should be managed, how they implement their knowledge and if it is consistent with the recommendation of European Society of Cardiology (ESC) and whether differences exists in practice between specialists. In the first phase the specialists, cardiologists and diabetologists, answered the questions about the management of different stages of HF. In second phase we analysed medical documentation of 345 patients aged between 38 and 98 years, hospitalised in Cardiology and Gastroenterology Departments from October 2000 to February 2002 by reason of coronary artery disease, hypertension and dilated cardiomyopathy. In the third phase we compared the knowledge of heart failure management from questionnaire and its implementation, the compliance with ESC recommendation and finally whether differences in clinical practice exist between cardiologist and diabetologists. RESULTS: ACE-I were prescribed in all NYHA classes of HF. In over 50% patients in II NYHA class to 94% in IV NYHA class in Cardiology Department. Differences between the Departments in prescribing of ACE-I were observed. Beta-blockers (BB) were used with the same frequency in all NYHA classes, more often in Cardiology Department. Frequency of the administration of digoxin, diuretics, aldosterone receptor blocker was increasing starting with II NYHA class. The highest compliance between declarations from questionnaire and clinical practice concerned the use of BB and ACE-I combination.  相似文献   
59.
60.
Background There is growing evidence from recent studies that atrial natriuretic peptide (ANP) plays an important part in coronary blood flow regulation and in atherosclerosis. Transition T2238→C in the atrial natriuretic peptide (ANP) precursor gene, which leads potentially to the translation of ANP with 2 additional arginines, has been suggested to be associated with salt-sensitive hypertension. According to our knowledge, this study is the first to look for the potential association of the ScaI ANP gene polymorphism with the history of nonfatal myocardial infarction and the extent of coronary artery disease (CAD).Methods The study was performed in 847 consecutive, white patients (719 men and 128 women) with significant coronary artery stenosis confirmed by means of elective coronary angiography (at least 1 coronary artery with ≥50% lumen narrowing). Screening for the T2238→C substitution was performed by means of polymerase chain reaction of genomic DNA, followed by ScaI digestion and agarose gel electrophoresis.Results We found a significant association of the A2A2 ScaI ANP genotype with a higher incidence of positive history of nonfatal myocardial infarction (odds ratio 1.85, 95% CI 1.33-2.58) and multiple-vessel CAD (odds ratio 1.45, 95% CI 1.02-2.06). The ScaI ANP genotype distribution did not differ with age, sex, body mass index, plasma lipids, hypertension, diabetes mellitus, and family history of CAD in studied groups.Conclusions Our results suggest that the ScaI ANP polymorphism may be associated with nonfatal myocardial infarction and the extent of CAD. However, the precise mechanism of this association remains to be determined. (Am Heart J 2003;145:125-31.)  相似文献   
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