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1.
In osteoimmunology, osteoclastogenesis is understood in the context of the immune system. Today, the in vitro model for osteoclastogenesis necessitates the addition of recombinant human receptor activator of nuclear factor kappa‐B ligand (RANKL) and macrophage colony‐stimulating factor (M‐CSF). The peripheral joints of patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA) are characterized by an immune‐mediated inflammation that can lead to bone destruction. Here, we evaluate spontaneous in vitro osteoclastogenesis in cultures of synovial fluid mononuclear cells (SFMCs) activated only in vivo. SFMCs were isolated and cultured for 21 days at 0.5–1.0 × 106 cells/mL in culture medium. SFMCs and healthy control peripheral blood monocytes were cultured with RANKL and M‐CSF as controls. Tartrate‐resistant acid phosphatase (TRAP) positive multinucleated cells were found in the SFMC cultures after 21 days. These cells expressed the osteoclast genes calcitonin receptor, cathepsin K, and integrin β3, formed lacunae on dentin plates and secreted matrix metalloproteinase 9 (MMP9) and TRAP. Adding RANKL and M‐CSF potentiated this secretion. In conclusion, we show that SFMCs from inflamed peripheral joints can spontaneously develop into functionally active osteoclasts ex vivo. Our study provides a simple in vitro model for studying inflammatory osteoclastogenesis.  相似文献   
2.
Biochemical and immunological properties were studied in crude mould extracts from 10 different strains of Alternaria alternata. The mould strains were grown on completely synthetic medium and harvested under identical conditions. The biochemical and immunological analyses (protein content, carbohydrate content, IEF, RAST-inhibition, CIE/CRIE and the content of a major allergen) showed significant variations between the individual strains of A. alternata. 32 antigens were identified in the CIE pattern of A. alternata and 19 different allergens were identified in CRIE analysis (1 major, 7 intermediate and 6 minor allergens). There was a significant variation in the content of the major A. alternata allergen (Ag-8, partially identical to Alt-I) between the different individual strains. Furthermore, a considerable variation in the content of Ag-8 was observed for a specific strain cultivated at different occasions under identical cultivation conditions during a time period of 3 years.  相似文献   
3.
PURPOSE: A retrospective, 12-year review of neonatal necrotizing enterocolitis was undertaken at a county hospital, with emphasis on presentation signs and symptoms. METHODS: Eighty-two patients with presence of intramural air were included in the study. The following signs and symptoms were studied: evidence of respiratory distress, use of umbilical catheters, white blood cell count and temperature at presentation, time interval from birth to diagnosis and time interval from diagnosis to operative intervention, presence of intramural air, air in biliary tree or free air, changes in abdominal girth, and presence of occult or gross blood in stools. Comparison was done among infants who had surgical or medical treatment, premature and full-term infants, and infants who had neonatal necrotizing enterocolitis less than or more than 20 days after birth. RESULTS: Eleven patients had a fatal outcome, with an overall survival of 87 percent. Sixty-four patients were treated medically and 18 had operative treatment. Mortality of the surgically treated group was 44 percent. Neonates who had surgical intervention had a left shift of the white blood cell count more commonly present, and all had documented abdominal distention. There were 62 premature and 20 full-term neonates in the group. Full-term neonates developed neonatal necrotizing enterocolitis earlier after birth (5.3 days compared with 15.3 days in the premature neonate group). Full-term neonates had a better prognosis in our series. Presentation of symptoms more than 20 days after birth did not change outcome. CONCLUSION: Our results reflect the experience of a community-based hospital. Clinical acumen remains the cornerstone of diagnosis and management.  相似文献   
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5.
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking.  相似文献   
6.
Blood samples were collected in peripheral venous blood of seven lactating sows, when their piglets were suckling. In four of the experiments samples were also taken when the sows were fed a meal. Gastrin, insulin, somatostatin and VIP levels were measured by radioimmunoassay. Insulin levels increased by approximately 100% for about 10 min in response to suckling, in some experiments even before the suckling occurred, i.e. when the sows saw, heard and smelled their piglets. In four of the sows suckling caused a biphasic twofold increase in gastrin levels - one immediate peak which lasted for a few min and a second peak of longer duration (about 30-60 min), whereas gastrin levels remained unchanged in three animals. Somatostatin levels usually reflected gastrin levels in a reciprocal way. Thus, a biphasic decrease of somatostatin levels occurred in the high gastrin responders. In contrast, somatostatin levels increased in the experiments, in which gastrin levels did not change. Immediate and short-lasting (a few minutes long) increases of VIP levels were also induced by suckling. Large litters and long suckling periods appeared to be related to greater changes of the levels of all the peptides measured. Feeding influenced insulin, gastrin and somatostatin levels in the same way as did suckling from both a qualitative and a quantitative point of view. In contrast, VIP levels were not increased by feeding. The possible functional effects of the suckling-induced release of gastrointestinal hormones and possible mechanisms of their release are discussed.  相似文献   
7.
IgE and IgG antibodies against Aspergillus fumigatus were detected by crossed radio immunoelectrophoresis (CRIE) on the sera of seven patients with aspergilloma, six patients with allergic broncho-pulmonary aspergillosis (ABPA) and 25 patients with extrinsic asthma with Aspergillus allergy. IgE-CRIE analysis indicated the presence of A. fumigatus-specific IgE in sera of patients with ABPA and Aspergillus asthma but not of aspergilloma patients. IgG-CRIE showed that both aspergilloma and ABPA patient sera contained high levels of circulating specific IgG antibodies in contrast to sera of Aspergillus asthma patients, which did not show detectable amounts of Aspergillus-specific IgG antibodies. Specific IgE binding could be demonstrated for the major allergens Ag-10 and AG-40 in all ABPA patients, in 80% of Aspergillus asthma patients but not in sera from aspergilloma patients. Specific IgG antibodies directed towards the major allergens could be detected in most of the aspergilloma patients, between 30-70% of the ABPA patients but not in sera from patients with Aspergillus asthma.  相似文献   
8.
This double-blind immunotherapy trial in children, using a purified and standardized Cladosporium herbarum allergen preparation, has shown that children with mould asthma and/or rhinoconjunctivitis, responded to immunotherapy with a decrease in specific IgE and a significant increase in specific IgG. There was a marked increase in the ratio specific IgG/specific IgE as a result of active treatment. IgE-CRIE radiostaining patterns showed no pronounced changes after 10 months' active treatment and no "new sensitivities" could be detected in the studied patients. IgG-CRIE radiostaining, primarily directed towards the important allergens, was significantly increased in the active group and particularly towards Ag-12 (partially identical to a previously described major allergen in Cladosporium herbarum, Ag-54). Children treated with histamine placebo showed no change in antibody patterns during 10 months of treatment.  相似文献   
9.
European Journal of Epidemiology - The apolipoprotein E allele 4 (APOE-ε4) is established as a major genetic risk factor for cognitive decline and late-onset Alzheimer’s disease....  相似文献   
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