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121.
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The etiology of Langerhans cell histiocytosis (LCH), a disease characterized by uncontrolled proliferation of Langerhans cells, is unknown. Although some believe that LCH is reactive, others support a neoplastic origin. We tested the hypothesis that LCH is neoplastic by investigating potential consistent chromosomal aberrations in LCH cells. We used multiparameter DNA flow cytometry to analyze the DNA ploidy LCH cells in 20 cases, performed karyotype analysis in 31 cases, array‐based comparative genomic hybridization (arrayCGH) and single nucleotide polymorphism (SNP) arrays with DNA from flow‐sorted CD1a‐positive and CD1a‐negative cells in 19 cases. Ploidy analysis revealed diploid DNA content in all cases. The karyotype of all patients analyzed was normal, excluding the presence of balanced translocations. ArrayCGH and SNP arrays did not show genome abnormalities. Despite positive TP53 protein immunohistochemical staining, sequencing of exon 5 to 8 of p53 gene showed no alterations in 7 cases. This study strongly suggests that gross chromosomal abnormalities do not cause LCH. Although we cannot exclude cryptic point mutations in as yet unidentified genes, this study of 72 LCH cases shows that LCH may be the result of restricted oligoclonal stimulation rather than unlimited neoplastic proliferation. © 2008 Wiley‐Liss, Inc.  相似文献   
123.
Celiac disease and dermatitis herpetiformis are caused by the alcohol soluble fractions of wheat, barley, and rye. Reliable serological tests are available for both mass and risk group screening and recent epidemiological studies on celiac disease suggest that the prevalence varies between 1 : 100–300 in different continents. The clinical manifestations of the disease has changed in the West and the classical symptomatic cases represent only approximately 1/7th of all diagnosed cases. Symptoms such as, anemia, short stature, dental enamel defect or osteoporosis can be the only manifestations of the atypical disease. There is an increased prevalence of celiac disease in patients with autoimmune diseases. Recent data suggest that there is a correlation between the prevalence of autoimmune diseases and the number of years that an individual consumes, gluten-containing foods. Genetic studies revealed a high prevalence of certain HLA antigens in celiac patients, however, there is likelihood that non-HIA genes are also important in the pathomechanism. An interesting new development is the recognition of tissue transglutaminase (tTG), an enzyme that probably forms an autoantigen with gluten. It is generally accepted that antibodies to tTG are identical to the previously described antiendomysium antibodies. Whether or not tTG is responsible for the initiation of an immunoreaction against prolamines or just exacerbates the immune response is a subject of further investigations.  相似文献   
124.
Celiac disease is an immune-mediated enteropathy caused by a permanent sensitivity to gluten in genetically susceptible individuals. It occurs in children and adolescents with gastrointestinal symptoms, dermatitis herpetiformis, dental enamel defects, osteoporosis, short stature, delayed puberty and persistent iron deficiency anemia and in asymptomatic individuals with type 1 diabetes, Down syndrome, Turner syndrome, Williams syndrome, selective immunoglobulin (Ig)A deficiency and first degree relatives of individuals with celiac disease. The Celiac Disease Guideline Committee of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition has formulated a clinical practice guideline for the diagnosis and treatment of pediatric celiac disease based on an integration of a systematic review of the medical literature combined with expert opinion.The Committee examined the indications for testing, the value of serological tests, human leukocyte antigen (HLA) typing and histopathology and the treatment and monitoring of children with celiac disease. It is recommended that children and adolescents with symptoms of celiac disease or an increased risk for celiac disease have a blood test for antibody to tissue transglutaminase (TTG), that those with an elevated TTG be referred to a pediatric gastroenterologist for an intestinal biopsy and that those with the characteristics of celiac disease on intestinal histopathology be treated with a strict gluten-free diet. This document represents the official recommendations of the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition on the diagnosis and treatment of celiac disease in children and adolescents.  相似文献   
125.
This article suggests conceptual and procedural limits on a strict operant approach to assessment in behavioral medicine. Several areas of concern to physicians and psychologists are discussed, highlighting the potential role of cognitive assessment methods. These areas include: pain, placebo, and expectancy effects, coping strategies, compliance/noncompliance with medical recommendations, self-regulatory disorders, and the broad domains of prediction and prevention. It is concluded that methods of gauging potentially important perceptual, evaluational, motivational, or stylistic mediators of health, illness, and response to medical treatment should be validated and included among the tools of the clinical assessor in behavioral medicine.  相似文献   
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Rhesus monkeys received intravenous injections of ethanol during daily sessions contingent on their presses on an available lever. Under the standard conditions, when each response on the lever during a 3-h period each day resulted in an i.v. injection of 0.1 g/kg ethanol, the monkeys made between 30 and 50 responses/session and developed blood ethanol levels of approximately 400 mg%. Under this and other conditions of response-contingent delivery of ethanol, a negatively accelerated pattern of self-injection within sessions was demonstrated. Variations in the dose per injection (0.05–0.2 g/kg/injection) resulted in changes in the rate of lever-pressing; the number of self-injections was inversely related to dose. Ethanol intake increased only slightly with increased dose per injection. Noncontingent administration of various doses of i.v. ethanol immediately prior to a daily session decreased the number of responses; the total amount of ethanol administered (contingent plus noncontingent), however, remained constant over a pretreatment dose range of 1 to 3 g/kg. When access time to ethanol was increased from 3 to 6 h/day, the total amount of ethanol taken increased slightly. However, the blood ethanol levels at the end of a 6-h session closely approximated those obtained following 3-h sessions, indicating that during the last 3–4 h of the 6-h sessions, the rate of ethanol intake closely matched the rate of ethanol elimination.  相似文献   
128.
Eighty-nine women with fibromyalgia completed the Life Orientation Test, identified health and social goals, and answered questions from the Goal Systems Assessment Battery (P. Karoly & L. Ruehlman, 1995) about their valuation of, and self-efficiency in attaining, each goal. For 30 days, they responded to palm-top computer interviews about their pain and fatigue and rated their goal effort, goal progress, and pain- and fatigue-related goal barriers. Goal barriers increased and goal efforts and progress decreased on days with greater pain and fatigue; goals valued more highly were pursued more effortfully and successfully; more optimistic individuals were less likely to perceive goal barriers and, on days that were more fatiguing than usual, were less likely to reduce their effort and to retreat from progress in achieving their health goal; and more pessimistic individuals perceived greater goal barriers on days that were less painful than usual.  相似文献   
129.
Autistic disorder is a pervasive developmental disorder manifested in the first 3 years of life by dysfunction in social interaction and communication. Many efforts have been made to explore the biologic basis of this disorder, but the etiology remains unknown. Recent publications describing upper gastrointestinal abnormalities and ileocolitis have focused attention on gastrointestinal function and morphology in these children. High prevalence of histologic abnormalities in the esophagus, stomach, small intestine and colon, and dysfunction of liver conjugation capacity and intestinal permeability were reported. Three surveys conducted in the United States described high prevalence of gastrointestinal symptoms in children with autistic disorder. Treatment of the digestive problems may have positive effects on their behavior.  相似文献   
130.
This study was designed to identify highly recurrent genetic alterations typical of Sézary syndrome (Sz), an aggressive cutaneous T-cell lymphoma/leukemia, possibly revealing pathogenetic mechanisms and novel therapeutic targets. High-resolution array-based comparative genomic hybridization was done on malignant T cells from 20 patients. Expression levels of selected biologically relevant genes residing within loci with frequent copy number alteration were measured using quantitative PCR. Combined binary ratio labeling-fluorescence in situ hybridization karyotyping was done on malignant cells from five patients. Minimal common regions with copy number alteration occurring in at least 35% of patients harbored 15 bona fide oncogenes and 3 tumor suppressor genes. Based on the function of the identified oncogenes and tumor suppressor genes, at least three molecular mechanisms are relevant in the pathogenesis of Sz. First, gain of cMYC and loss of cMYC antagonists (MXI1 and MNT) were observed in 75% and 40% to 55% of patients, respectively, which were frequently associated with deregulated gene expression. The presence of cMYC/MAX protein heterodimers in Sézary cells was confirmed using a proximity ligation assay. Second, a region containing TP53 and genome maintenance genes (RPA1/HIC1) was lost in the majority of patients. Third, the interleukin 2 (IL-2) pathway was affected by gain of STAT3/STAT5 and IL-2 (receptor) genes in 75% and 30%, respectively, and loss of TCF8 and DUSP5 in at least 45% of patients. In sum, the Sz genome is characterized by gross chromosomal instability with highly recurrent gains and losses. Prominent among deregulated genes are those encoding cMYC, cMYC-regulating proteins, mediators of MYC-induced apoptosis, and IL-2 signaling pathway components.  相似文献   
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