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11.
A sample of 1271 visually handicapped children has been analysed with regard to the degree and cause of visual impairment.  相似文献   
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Summary. All stillbirths and neonatal deaths occurring in the North East Thames region were studied in 1983. This report describes the socio-economic and ethnic differences in that cohort. The stillbirth and neonatal mortality rates of babies born to fathers of social class V (16–8 per 1000 total births) was almost double that of social class I fathers (8–6 per 1000 total births). The most marked social class gradient was seen in the macerated stillbirth groups. Of particular concern was the extremely high stillbirth and neonatal mortality rate for women born in the Indian subcontinent. This was most evident in Pakistani women who had a stillbirth plus neonatal mortality rate of 17.3 per 1000 total births, almost twice that of the women born in the UK (9.0 per 1000 total births). Again, as with social class, macerated stillbirths appeared to contribute disproportionately to the excess mortality. Mortality rates were aggre gated into four birthweight specific groups. Asian women had higher mortality rates in the higher birthweight groups, whereas in the lower birthweight group their babies did slightly better. This study indicated that the special needs for working class and ethnic minority mothers within NE Thames were not being met, and the Regional Health Authority was strongly recommended to review services to these groups.  相似文献   
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Acetaldehyde, the major metabolite of ethanol, reacts with lysineand other free amino groups on proteins to form acetaldehyde-proteinadducts. The presence of antibodies which recognize such acetaldehyde-proteinadducts in sera from alcoholics has been attributed to an immuneresponse to such adducts. Complicating this conclusion is thefinding that sera from non-alcoholic control subjects also containantibodies which recognize acetaldehyde-protein adducts. Inthe current research we sought to determine whether antibodieswhich recognize epitopes formed by the reaction of a proteinwith acetaldehyde can be formed in response to a protein modifiedwith a structurally related protein adduct. We modified lysineresidues on apolipoprotein (apo) B-100 with acetaldehyde andformaldehyde under reducing conditions, to form -N-methyl-and-N-ethyl-lysine residues, and with acetic anhydride to form-N-acetyl-lysine residues, and made antibodies against thesemodified proteins in guinea-pigs. In ELISA assays antibodiesmade against methylated apoB-100 (Me-apoB) cross-reacted effectivelywith ethylated apoB-100 (Et-apoB), while antibodies made againstacetic anhydride-modified apoB-100 did not cross-react. We concludethat methyl-lysine shares one or more immunoreactive epitopeswith ethyl-lysine, and that antibodies which recognize acetaldehyde-modifiedproteins can be formed in response to formaldehyde-modifiedproteins. We demonstrate that sera from both alcoholics andnon-drinkers contain antibodies which recognize Me-apoB andEt-apoB and that the titres of these antibodies are comparable.These data raise the possibility that some human serum antibodieswhich recognize acetaldehyde-modified protein epitopes may havebeen made against formaldehyde-modified protein epitopes. Thesedata also illustrate the difficulty in assigning a unique causalrelationship between the presence of an antibody, and the immunogenresponsible for the formation of such antibody.  相似文献   
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The aim of the present study is to evaluate drawbacks and advantagesof the choice of hospital versus population controls in a casecontrol study on diet and cancer through the analysis of a retrospectivestudy on diet and gastric cancer (GC) conducted in Forli, Italy,involving 232 cases, 430 population controls and 252 hospitalizedcontrols. The present paper reports the comparison of resultson diet and GC risk obtained using the 2 types of controls.Population controls tended, in general, to eat all kinds offoods slightly more frequently (bread, pasta, cold cuts, freshfish, seasoned cheeses, legumes, garlic, onions and preservedfruits), with the exception of cooked vegetables, which werereported less frequently by population than by hospital controls.ORs for specific foods adjusted for confounders and other foodswere consistent in the separate models including populationand hospital controls respectively for all food groups, withthe exception of cooked vegetables which represented a protectivefactor only when hospital controls were considered (high consumers,population controls: adjusted, OR=0.9, trend p value 0.54; highconsumers, hospital controls, adjusted OR=0.5, trend p value<0.01). Hospital controls were slightly less often currentsmokers (22.6 versus 30.0%) and more often regular wine drinkers(57.5 versus 47.8%) compared with population controls, but noneof these variables was associated with GC risk. The main resultsin this study were consistent using both types of controls,nevertheless the distribution of some dietary variables notrelated to the disease under study differed between the 2 controlgroups, suggesting some caution in the use of hospital controlswhen studying diseases other than GC.  相似文献   
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Abstract — The effect of 8 polyols and 14 aldoses or ketoses on the spontaneous aggregation of Ca-proteinates was followed spectrophotometrically in supernatants and filtrates of human mixed saliva. Each carbohydrate was added to the saliva samples at 37°C and the precipitated material was analyzed for protein, total carbohydrate and Ca. Based on their effect on aggregation, the carbohydrates could be divided into three groups: 1) those that showed no effect on aggregation: D-xylose, D-ribose and i-erythritol, 2) those that inhibited aggregation strongly: xylitol, Dsorbitol and D-mannitoi, and 3) those that inhibited aggregation moderately: glucose, fructose and sucrose. The inhibitory effect of the above polyols on the aggregation of Ca-proteinates varied greatly among the saliva donors, and correlated positively with the turbidity of the saliva and its protein content more than with the Ca-concentration or the pH of the saliva sample. It is suggested that inhibition of aggregation shown the most clearly for xylitol, sorbitol and mannitol manifests itself as a retardation of the final, irreversible aggregation of those glycoproteins that already exist in a precipitated form and which are responsible for the turbidity of saliva.  相似文献   
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ABSTRACT. Forty-four myeloma patients with large tumour cell mass and impairment of renal function (S-creatinine >2 mg/dl, stage III B) were studied. Seven patients, who received no active treatment, neither cytostatics nor plasmapheresis, survived for >1 month (median). Twenty-one patients who were treated with chemotherapy combination (M-2 protocol: melphalan, vincristine, BCNU, cyclophosphamide, prednisone) plus plasma exchanges for three days at the start of each 5-week cycle survived longer (median 17 months, p<0.01) than 16 pateints who were treated with melphalan-prednisolone alone (median 2 months). However, better supportive care, dialysis, and improved antibiotic treatment may also have contributed to the improved results. It is concluded that intensive chemotherapy in full dosage, plasmapheresis, and active uremia treatment including dialysis should be considered in patients with advanced myeloma and renal failure.  相似文献   
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Abstract— Great variations reported in the frequency distribution of buffer capacity values may partly be due to methodological differences in saliva sampling. In this study we wanted to see to what extent these variations are due to repetition and prestimulation. 9-yr-old schoolchildren ( n : 41, 23 girls and 18 boys), who had never had saliva samples taken before, participated in the present study. The repetition tests were carried out between 9 and 11 a.m. on three subsequent days. The effect of prestimulation was tested 4 days later with the same subjects. The buffer capacity of the samples was determined electrometrically immediately after sampling using the commercial Dentobuff-test. The intraindividual analysis revealed a significant increase in flow rate but not in buffer capacity along with repetition of the sampling. The analysis further showed that the buffer capacity of children accustomed to saliva sampling increased significantly through prestimulation of 1 min. The use of prestimulation resulted in substantial changes also in the frequency distribution of the buffer capacity values. Our results emphasize the importance of proper sampling conditions in saliva collection when screening children for high caries risk.  相似文献   
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Hallander HO, Andersson M, Gustafsson L, Ljungman M, Netterlid E. Seroprevalence of pertussis antitoxin (anti‐PT) in Sweden before and 10 years after the introduction of a universal childhood pertussis vaccination program. APMIS 2009; 117: 912–22. The prevalence of IgG ELISA antibodies against pertussis toxin (anti‐PT) was studied in two Swedish seroepidemiological studies. One was performed in 1997 when the new pertussis vaccination program was 1 year old (n = 3420). In 2007, when Pa vaccines had been used countrywide for 10 years in the universal child vaccination program, this study was repeated to analyze the effect of vaccination on anti‐PT prevalence (n = 2379). Before the statistical analysis of seroprevalence, children vaccinated within the last 2 years before the serosurveys were excluded. The results indicate a reduced exposure to Bordetella pertussis in the population. The proportion of sera without measurable anti‐PT antibodies increased significantly, aggregated over all comparable age groups, from 3.8% in people sampled in 1997 to 16.3% in people sampled in 2007. For cord blood, 1% was without measurable anti‐PT antibodies in 1997 compared to a significantly higher level, 12%, in 2007. With anti‐PT concentrations of ≥50 and ≥100 EU/ml as cutoff points for ‘recent infection’ the proportion above the cutoff points for younger children was significantly higher in 1997 than in 2007 at both cutoff points. For all adults, 20 years of age and older, the difference in proportions above the lower cutoff point was close to statistically significant, comparing 1997 with 2007. This was not the case at 100 EU/ml. In the 1997 samples of children, there was a significant downward trend of ‘recent infections’ at both cutoff points for three sampled age groups between 5 and 15 years of age from 21% at 5.0–5.5 years of age to 7% at 14.7–15.7 years for the lowest cutoff. In the 2007 samples of children, on the contrary, there was a significant continuous upward trend of ‘recent infections’, at both cutoff points, for four sampled age groups between 4 and 18 years of age – from 4% at 4–5 years of age to 16% at 17–18 years at the lowest cutoff. The continuous increase, with age of children with high anti‐PT concentrations, supports the recent change in the general Swedish childhood vaccination program to include a pre‐school booster at 5–6 years and a school‐leaving booster at 14–16 years of age.  相似文献   
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