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1.
A population-based survey was conducted in northern Finland in order to study the incidence rate and survival in patients with pharyngeal cancer diagnosed between 1986 to 1996. A total of 95 new patients with hypopharyngeal, oropharyngeal or nasopharyngeal cancers were identified. The overall age-adjusted incidence rates (per 100,000 years) were 1.28 in men and 0.60 in women, giving an overall incidence rate of 0.89. Most of the tumours were diagnosed at stage IV, and the median disease-specific survival times were 27.6 months for the patients with oropharyngeal cancer, 13.5 months for nasopharyngeal cancer and 17.7 for hypopharyngeal cancer. The most important factors that were associated with a poor prognosis were stage IV in oropharyngeal [Hazard ratio (HR) 3.68, 95% confidence interval (CI) 0.97-13.92] and hypopharyngeal cancer (HR 3.99, CI 1.51-10.67) and age over 65 years in nasopharyngeal cancer (HR 9.28, CI 1.79-47.99).  相似文献   
2.
The NTP has a long history of using Fischer rats and has compiled a large database of incidences of lesions seen in control animals. Such a database is lacking for Harlan Sprague-Dawley (SD) rats. The intention of this paper is to report spontaneous lesions observed in female vehicle control Harlan SD rats, and to compare the incidence in 2 strains of rats (Fischer and Harlan SD) used in NTP studies. Female Harlan SD rats served as the test animals for a special series of 2-year studies. Male rats were not used in these studies. Complete histopathology was performed on all animals, and the pathology results underwent comprehensive NTP pathology peer review. The most commonly observed neoplasms in these female control Harlan SD rats were mammary gland fibroadenoma (71%), tumors of the pars distalis of the pituitary (41%) and thyroid gland C-cell tumors (30%). Female Fischer rats had incidences of 44% for mammary gland fibroadenomas, 34% for tumors of the pars distalis, and 16% for thyroid gland C-cell tumors. Fischer rats had a 15% incidence of clitoral gland tumors, while the Harlan SD rats had an incidence of < 1%. In contrast to Fischer F344 rats, the Harlan SD rats had a high incidence of squamous metaplasia of the uterus (44.2%). Squamous metaplasia is not a lesion commonly observed in NTP control Fischer rats. The Harlan SD rats had a very low incidence of mononuclear cell leukemia (0.5%), compared with an incidence of 24% in female Fischer rats.  相似文献   
3.
Guilty Knowledge Test measuring electrodermal reactions was carried out in order to investigate the quality of different questions and the validity of the test in a situation that resembled a true crime. Fifty participants were randomly assigned to commit one of two realistic mock crimes, and were later tested with GKTs concerning both the crime they had enacted and the one they had no knowledge of. Different scoring systems (SCRs and peak amplitudes as well as raw and standardised scores) were employed and compared when analyzing the results. Although there were some false positives, the test was able to differentiate between the groups of guilty and innocent participants. With the best scoring systems, the test was able to classify up to 84% of the innocent and up to 76% of the guilty correctly according to a logistic regression analysis. ROC areas reflecting these same results reached values above .80. Questions on matters that demanded the participants' attention and were easier to remember had better discriminative power. With nearly all scoring methods, there was a significant interaction between the salience of the relevant items and the guilt of the participants. Participants reacted more strongly to salient relevant items when they were guilty, while no different reactions were observed for the non-salient items between guilty and innocent participants. It is suggested that, although the Guilty Knowledge Test appears to be a valid measure of guilty knowledge even in crimes that are close to real crimes, the principles on which guilty knowledge test questions are constructed should be more clearly specified.  相似文献   
4.
The anticonvulsant drug phenytoin, in less than cytotoxic concentrations, caused significant reductions in Ig secretion by unstimulated or EBV-stimulated normal MNC, as measured by PFC or secretion of Ig into the culture medium. Isotype-specific LBL varied in their sensitivity, the secretion of IgA (1 line) and IgG (3 lines) being reduced by phenytoin near therapeutic concentrations, whereas that of IgM (1 line) was resistant. Six-day exposure of MNC to phenytoin caused no selective depletion of or enrichment for B cells, monocytes or T cell subsets. The results suggest that the reduction in serum Ig levels reported in phenytoin-treated epileptic patients is, at least in part, due to a direct effect of the drug on the B lymphocyte. However, among EBV-activated normal MNC, those secreting IgA were no more sensitive to the drug than those secreting IgG or IgM, and other factors may, therefore, operate to cause the preferential reduction in serum IgA in phenytoin-treated patients.  相似文献   
5.
An outbreak of infections caused by Legionella pneumophila serogroup 5 was detected in a university hospital, and nosocomial reservoirs of the legionella epidemic were examined. Clinical isolates from two patients who had been affected by the L. pneumophila serogroup 5 outbreak, and from another patient with a legionella infection caused by the same serogroup 3 years later, were compared to L. pneumophila serogroup 5 isolates from the hospital water supply by two molecular methods, amplified fragment length polymorphism (AFLP) analysis and random amplified polymorphic DNA analysis (RAPD). Genotyping confirmed the epidemiological linkage of the first two patients, and linked their infections with the hospital water supply. The third clinical strain, which was also linked to the hospital water, was very similar to the epidemic strain. Even though the water distribution system was sanitized (superheat and flush sanitation), the epidemic strain was shown to be persisting in the hospital water outlets several years after its initial discovery.  相似文献   
6.
BACKGROUND: The aim of the European Sero-Epidemiology Network (ESEN2) is to harmonise the serological surveillance of vaccine-preventable diseases in Europe. OBJECTIVE: To allow comparison of antibody prevalence in different countries by standardising results into common units. STUDY DESIGN: For varicella zoster virus (VZV), a reference laboratory established a panel of 148 samples, characterised by indirect enzyme-immunoassay (ELISA), indirect immunofluorescence, and complement fixation test. Fifty-seven samples were also studied by the fluorescence antibody to membrane antigen test. The geometric mean of the antibody activity (GMAA) obtained from four ELISA determinations was used to characterise each sample of the panel as positive (GMAA: >100 mIU/ml), equivocal (GMAA: 50-100 mIU/ml) or negative (GMAA: <50 mIU/ml) for antibody to VZV (anti-VZV). Thirteen laboratories, using five different ELISA tests, tested the panel. RESULTS: Agreement with the reference laboratory was above 85% in all cases, and the R(2) values obtained from regression analysis of the quantitative results were always higher than 0.87. Finally, the regression equations could be used to convert national values into a common unitage. CONCLUSION: This study confirmed that results for anti-VZV obtained by different ELISA methods can be converted into common units, enabling the comparison of the seroprevalence profiles obtained in the participant countries.  相似文献   
7.
Reactive lymph nodes, palatine tonsils and thyroid tissues infiltrated with reactive lymphatic tissue were studied for the presence of immunoreactive acid cysteine-proteinase inhibitor (ACPI). A positive reaction for ACPI was found in germinal centres in all the above tissue types. The morphology and distribution of the positive cells indicated immunoreactivity in the dendritic reticulum cells (DRC). A positive reaction was also found in starry sky cells when a strong starry sky reaction was present in germinal centres. ACPI-positive cells of dendritic appearance were also found outside the secondary follicles in tonsillar tissue from cases of chronic or recurrent tonsillitis, especially between the follicles and the crypt epithelium, in some lymph nodes exhibiting a strong follicular reactive hyperplasia and in thyroid tissue in one case of Hashimoto's thyroiditis. A close anatomical and morphological relationship is pointed out between ACPI reactive dendritic cells and epithelial tissue. This is especially true of the tonsillar crypt epithelium and adjacent lymphoid secondary follicles. The tonsillar crypt epithelium sometimes formed a loose, web-like structure with enmeshed lymphoid cells, even reminiscent of dendritic compartmentalization of lymphoid secondary follicles. The results suggest that ACPI-immunoreactivity of DRC could be a function of the outer membrane of dendritic processes, and thus could be in some way a parallel phenomenon to the morphological expression of the well-established function of DRC in capturing antigen and immune complexes.  相似文献   
8.
Selenium and immune functions in humans   总被引:3,自引:0,他引:3       下载免费PDF全文
Earlier animal experiments have shown that selenium depletion may decrease immune functions. In this human study, 40 volunteers from a population with low serum selenium concentrations were supplemented with selenium or placebo for 11 weeks. Blood samples were drawn at intervals for analysis of selenium status and immune function. At the end of the supplementation period, plasma selenium levels were 74 ng/ml in the placebo group and 169 ng/ml in the supplemented group. The improvement in selenium status was associated with a 57% increase in the activity of platelet glutathione peroxidase in the group supplemented with selenium, but there was no increase in the activity of this enzyme in the placebo-treated subjects. Immune function was measured in vitro by tests of lymphocyte and granulocyte activity. Intracellular killing of Staphylococcus aureus by granulocytes was slightly lower in the placebo group than in the selenium group at the end of the supplementation period (77.2 compared to 85.2%; P less than 0.05). No significant changes were observed in phagocytosis, chemotactic factor generation, antibody or leukocyte migration inhibitory factor production by lymphocytes, or proliferative responses to phytohemagglutinin or concanavalin A. These results suggest that the selenium deficiency of the order found in Finland and some other areas of the world has little, if any, influence on the immune functions measured in this study.  相似文献   
9.
OBJECTIVE: To analyze food consumption, nutrient intakes and serum cholesterol concentrations of the parents in a child-targeted CHD intervention trial, during which the age of children increased from 7 months to 5 y. DESIGN AND SUBJECTS: The children were randomized to an intervention group (n = 540) or a control group (n = 522) at six months of age. The intervention families were counseled at 3-6 month intervals to reduce their child's intake of saturated fat and cholesterol. Dietary issues were discussed with the control families only briefly. The parents' food consumption was analyzed by 24 h dietary recall at the child's age of 7 and 13 months and at 2, 3, 4, and 5 y. Nutrient intakes were calculated using the Micro-Nutrica program. RESULTS: The mothers and fathers of the intervention children used less butter, more margarine and more skim milk than those of the control children (P < 0.001 for all measurements). After the onset of counseling, the intervention mothers consumed continuously less fat (1.4 E% less at the child's age of 5 y), less saturated fat (1.5 E% less at the child's age of 5 y) and more polyunsaturated fat (0.5 E% more at the child's age of 5 y) than the control mothers (P = 0.008, P < 0.001 and P < 0.001 for trend, respectively). After the child's age of 13 months the intervention fathers also had a continuously lower fat intake (2.4 E% less at the child's age of 5 y) and consumed less saturated fat (1.5 E% less at the child's age of 5 y) than the control fathers (P < 0.001 for trend for both measurements). The serum cholesterol concentration of the intervention mothers was consistently lower than that of the control mothers during the intervention (at child's age of 5 y 4.86 and 5.09 mmol/L, respectively; P for trend = 0.03), while the values of the intervention and control fathers showed no differences. CONCLUSIONS: Continuous dietary intervention begun in infancy and focused on modification of the child's diet according to the current principles of preventive cardiology, was accompanied by a moderate decrease in the intake of total and saturated fat in the parents, but serum cholesterol concentration diminished consistently only in the mothers of the intervention children.  相似文献   
10.
We studied the effect of fluvoxamine and erythromycin on the pharmacokinetics of ropivacaine in a double-blinded, randomized, four-way cross-over study. Eight healthy volunteers ingested daily 1500 mg erythromycin for 6 days, 100 mg fluvoxamine for 5 days (Days 2-6), both erythromycin and fluvoxamine, or placebo. On Day 6, each subject received a single dose of 0.6 mg/kg ropivacaine IV over 30 min. Ropivacaine, 3-hydroxyropivacaine, and 2',6'-pipecoloxylidide in venous plasma and urine samples were measured for up to 12 h and 24 h, respectively. Fluvoxamine increased the area under the drug plasma concentration-time curve (AUC) of ropivacaine 3.7-fold (P: < 0.001), prolonged the elimination half-life (t(1/2)) from 2.3 to 7.4 h (P: < 0.01), and decreased the clearance by 77% (P: < 0.001). Erythromycin alone had only a minor effect on the pharmacokinetics of ropivacaine. However, when compared with fluvoxamine alone, the combination of fluvoxamine and erythromycin further increased the area under the drug plasma concentration-time curve and t(1/2) of ropivacaine by 50% (P: < 0.01). We conclude that inhibition of CYP1A2 by fluvoxamine considerably reduces elimination of ropivacaine. Concomitant use of fluvoxamine and CYP3A4 inhibitor erythromycin further increases plasma ropivacaine concentration by decreasing its clearance. Implications: Clinicians should be aware of the possibility of increased toxicity of ropivacaine when used together with inhibitors of CYP1A2. Concomitant use of CYP1A2 and CYP3A4 inhibitors further increases ropivacaine concentration.  相似文献   
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