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41.
Immunoglobulin G subclass concentrations were measured in paired foetal (cord) and maternal serum specimens at delivery from 27 IgA-deficient (serum IgA < 0.01 g/l) and 15 control women. IgA-deficient women had significantly higher serum IgGl and IgG3 concentrations than control women but 2 of the group had concomitant IgG2/IgG4 deficiency and a further 12 had low IgG4 concentrations (serum IgG4 < 0.025 g/l). Foetal serum also had significantly higher IgGl concentrations than control foetal serum but lower IgG2 and IgG4 levels. Concentrations of IgG subclasses and IgM were measured in breast milk collected on the fifth day postpartum from 19 of these IgA-deficient and 18 control women. Between-group differences in IgG subclass levels resembled those in serum. Compared with serum, proportionally less IgG3 was present in milk in both groups although the contribution of IgG3 to total IgG was not less than that of IgG4. Slightly higher IgM was found in milk from the IgA-deficient mothers.  相似文献   
42.
43.
Stroke is amenable to the entire spectrum of health services, ranging from prevention of its risk factors, to the treatment of acute stroke and rehabilitation and palliation of stroke. The aim of this study was to determine the number of persons with the capacity to benefit from evidence-based effective stroke services. Population-based survey and registry data along with published, evidence-based recommendations for services were used to determine the number of persons in Eastern Ontario with stroke (including risk factors, acute stroke and chronic stroke) and their related need for services (including prevention programs, diagnostic services, treatment of acute stroke and rehabilitation). These estimates were then compared to the actual provision of these services. Estimates of the need for effective services exceeded the provision of all services with the exception of pharmacologic treatment for diabetes mellitus and carotid endarterectomy for acute stroke. The approach was able to identify both the under-provision and over-provision of evidence-based effective services for stroke. This study has shown that an epidemiologically-based needs assessment could be a useful basis for the planning of health services.  相似文献   
44.
Genetic variations in DNA repair genes are thought to play an important role in the pathogenesis and development of non‐Hodgkin lymphoma (NHL). To further explore this hypothesis, we genotyped 319 tag single nucleotide polymorphisms (SNPs) in 27 DNA repair gene regions in 1946 cases and 1808 controls pooled from three population‐based case‐control studies of NHL in the US and Australia. Relative risks of NHL and NHL subtypes in relation to SNP genotypes were assessed using logistic regression. Associations of gene regions and pathways with NHL or NHL subtypes were explored using the minP and tail‐strength statistics, respectively. Overall, genetic polymorphisms within the DNA repair pathway were associated with NHL (P = 0·005). Similar associations were seen with the double‐strand break repair (P = 0·02) and nucleotide excision repair (P = 0·04) pathways. Five SNPs (BLM rs441399, RAD50 rs2237060, FAM82A2 rs2304583, ERCC3 rs4150506, and XRCC4 rs13178127) were particularly noteworthy because their gene regions were significantly associated with NHL or NHL subtypes (minP ≤ 0·05), or because of high level of statistical significance (P ≤ 0·005) and consistent findings across the three studies. These results support the hypothesis that common genetic polymorphisms in human DNA repair genes may modify the risk of NHL.  相似文献   
45.
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation.  相似文献   
46.
ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease.  相似文献   
47.
Sympathetic nervous control of cat ileocecal sphincter   总被引:1,自引:0,他引:1  
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48.
In spite of the fact that injury warning labels have been placed on radiator caps for the last 15 years, automobile radiator scald burns continue to be a burn prevention problem. The temperature of radiator fluid may be as high as 100 degrees F to 250 degrees F in a properly functioning car and higher in an overheated vehicle. From 1974 to 1990, 100 patients with burns that were caused by automobile radiators have been admitted to the Parkland Memorial Hospital Burn Unit (1.5% of acute admissions). Eighty-two percent of the injuries occurred in the summer months, and 93% of the patients were male. Mean age was 31 +/- 17 years (range, 8 months to 79 years), and mean burn size was 11.3% total body surface area (TBSA) (range, 1% to 32%) with a mean full-thickness burn size of 0.6% TBSA. Length of stay was 7 +/- 7.4 days (range, 1 to 38 days). Burns to the face, neck, and trunk necessitated most admissions. Although there were no deaths, five patients required intensive care for airway monitoring; mean length of stay was 6 days. One patient required endotracheal intubation for a total of 11 days. Ten patients required one or more skin grafting procedures, and three patients required burn resuscitation. Four patients sustained minor ocular injuries. A subgroup of patients demands special review: 10 children younger than 10 years of age (mean age, 4.1 years) of which 70% were boys. Mean burn size was 15.5% TBSA; mean full-thickness burn size was 2.4% (four times larger than the mean burn size for the adult population).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
49.
Assault by burning is an often unappreciated cause of burn injury. One hundred forty-eight of 3678 adults admitted to a major burn center with acute burn injuries sustained their burns as a result of an assault by another adult. High-risk groups included blacks and alcohol abusers. Patients were extremely reductant to describe the cause of their injury and to identify their assailant. In contrast to child abuse, very few cases go to court due to the patient's failure to press charges. There was no typical burn pattern, although the injury often did not coincide with the initial medical history. The presence of multiple trauma, occurring in 16% of these patients, must be excluded in the assaulted patient.  相似文献   
50.
Blood transfusion is one of the principal routes of transmission of Chagas' disease, a major endemic disease in Latin America. Methods for blood screening are not accurate and may yield false results that lead to high social and economic costs. This study compares two methods of diagnosing Chagas' disease (indirect immunofluorescence and hemagglutination) and several enzyme-linked immunosorbent assays (ELISAs) with regard to specificity and sensitivity, by using human sera with known serologic and parasitologic characteristics, as well as samples with discrepant results on conventional serologic tests. An ELISA using recombinant antigens showed no cross-reactivity with sera that were positive for other diseases. All evaluated ELISAs performed well, and their use may lead to a reduction of more than 50 percent in the number of discordant sera. Further improvements are needed in view of the complexity of the serologic diagnosis of Chagas' disease.  相似文献   
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