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21.
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   
22.
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   
23.
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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25.
In order to investigate possible differences in the reaction to hypoxic conditions between “red” and “white” skeletal muscle, cats were subjected to a 2 h period of either hemorrhagic shock or hind limb tourniquet ischemia, and the hypoxia induced changes were studied in the soleus and lateral gastrocnemius muscles. Muscle biopsies were analysed for ATP, CP, glucose, G 6–P and lactate. Using microelectrodes, the resting membrane potential was repeatedly measured. Both experimental models resulted in increased tissue lactate levels and a successive decrease in the membrane potential of both muscles studied. No reduction of the high energy phosphagen content (ATP+CP) occurred in any of the muscles during shock. The tourniquet ischemia resulted in a 40% reduction of the ATP+CP content in the soleus muscle, whereas in the gastrocnemius muscle no significant reduction occurred. A significant correlation was found between the tissue lactate content and the membrane potential under both conditions and in both muscles studied. It is concluded that “red” muscles are more susceptible to metabolic derangement than “white” muscles during total ischemia, whereas during hypovolemia “red” muscles appear to be protected from early hypoxic damage, probably due to a redistribution of skeletal muscle blood flow.  相似文献   
26.
ABSTRACT The prevalence of hyperglycaemia and undiagnosed diabetes mellitus was assessed in 214 consecutive patients admitted to the coronary care units with acute myocardial infarction (AMI). On admission, 16 patients (7.5%) had known diabetes, and 19 patients, not previously known to be diabetic, had blood glucose concentrations of ≥9 mmol/1. Fifteen patients survived for 2 months at which time a 75 g oral glucose tolerance test showed diabetes in 9 (60%) and impaired glucose tolerance in 4 (27%). Ten of these 13 patients (77%) with abnormal glucose tolerance had elevated glycosylated haemoglobin (HbA1c) on admission, indicating pre-existing glucose intolerance or diabetes. The prevalence of undiagnosed diabetes was 4.5% (9/198). However, we may have overlooked undiagnosed diabetes in a small number of patients on admission, since only a random blood glucose <8 mmol/1 rules out diabetes, WHO criteria. Elevated blood glucose in patients with AMI is more likely to reflect a stationary pre-existing abnormal glucose tolerance than a temporary stress-induced phenomenon.  相似文献   
27.
The aim of this study was to analyse how a sample of Finnish pharmacists perceived a number of video-taped customers requesting over-the-counter medicines. The conceptual basis of the study was cognitive psychology. Eleven female pharmacists took part in the study. In a questionnaire, each pharmacist was asked how she perceived each customer and to say what information she would have given the customer if time was available in the pharmacy. This was followed by a set of questions to which the pharmacist responded by using the ordinal scales provided. The data were analysed by a combination of qualitative and quantitative methods. The reaction to a specific situation was found to vary considerably among the pharmacists and was influenced by the cognitive structures of the pharmacist, the perceived personal qualities of the customer and the situation. The pharmacists indicated that they would give health information to complement information about the OTC preparation if time was available. Customers who were presumed to be independent would be given more information about side effects and alternative preparations than other customers.  相似文献   
28.
Anaerobic bacteria belonging to the species Bacteroides melaninogenicus, Bacteroides asaccharolyticus, Fusobacterium nucleatum, Peptostreptococcus anaerobius and Eubacterium alactolyticurn, isolated from necrotic dental pulps, were tested for their capacity to induce neutrophil leukocyte chemotaxis. Generation of chemotactic factors in serum by whole bacterial cells and chemotaxis induced by bacterial extracts were studied in vitro by the Boyden technique. Subcutaneously implanted wound chambers in guinea pigs were used for testing leukocyte migration in vivo. All bacterial strains had a similar high capacity to induce neutrophil chemotaxis. The heavy accumulation of polymorphonuclear neutrophil leukocytes associated with clinical and experimental infections by B. melaninogenicus or B. asaccharolyticus cannot be ascribed to any extreme ability of these organisms to generate chemotactic factors.  相似文献   
29.
Motile human sperm were collected from a Percoll gradient and the effects on sperm motility of human serum, various serum fractions, follicular fluid and seminal plasma were assessed. In culture medium alone (RPMI-1640) sperm motility was lost after about 5 h. The addition of male blood serum both enhanced sperm motility and prolonged viability very significantly. Albumin, seminal plasma and follicular fluid all stimulated sperm motility but to a much lesser extent than did blood serum. No difference was noted between male serum or female serum which had been collected during the follicular or luteal phases of hormone-stimulated cycles and which contained high levels of oestradiol. Serum fractions obtained by separation on Sephacryl S-300 column were tested for their ability to enhance sperm motility. The most pronounced effect, much superior to that achieved by the albumin fraction, was obtained by a fraction with a molecular weight of around 200 kD. In conclusion, certain factors in human serum, which are different from albumin, strongly support sperm motility. The high serum concentrations of oestradiol resulting from hormone stimulation for in-vitro fertilization do not invalidate the use of serum from the same patient during sperm preparation, or in the medium used for ovum insemination and culture.  相似文献   
30.
Separation of the epidermis from dermis to produce blisters by means of suction has been studied in relation to bullous pemphigoid and certain other skin disorders. There is a correlation between the time taken to produce blisters and the activity of pemphigoid and it is suggested that the technique can be of value in following the course of this disease and as a quantitative method for studying epidermodermal adherence in vivo.  相似文献   
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