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991.
The presence of CYP2D in pig livers has been studied using different strains of pig, different CYP2D test substrates and monoclonal and polyclonal antibodies. The results of the studies lacked consistency, therefore the aim of this study was to identify the reasons for these inconsistencies. Liver microsomes isolated from conventional pigs and minipigs were tested in Western blotting using both monoclonal and polyclonal antibodies against human CYP2D6. The microsomes were also incubated with three different CYP2D tes t substrates.'The immunoblotting only gave a positive response when hybridised with polyclonal antibody. The pig microsomes did not metabolise debrisoquine, but metabolised two other test substrates, dextromethorphan and bufuralol. No correlation was found between the two enzyme assays and CYP2D apoprotein level. On the other hand positive correlations were found between dextromethorphan and bufuralol metabolism and the CYP2B immunochemical protein level, indicating that the CYP2B isoenzyme may be involved in the metabolism of these substrates. Further, assays using immunoinhibition and chemical inhibition of these reactions were performed. No response was obtained in the immunoinhibition assay. When using chemical inhibition, however, an average inhibition percentage of 83 were obtained with orphenadrine, a human CYP2B inhibitor. Average Ki values of 26.9 microM and 43.6 microM for orphenadrine indicate that it was a potent inhibitor. A rat and a mouse CYP2B inhibitor, resveratrol and pilocarpine, inhibited the reaction with an average of 40 and 70 percentage respectively. Orphenadrine did not inhibit CYPIA, CYP2A, CYP2E and CYP3A activities up to more than maximum 12 percentage, showing that it was almost selective for dextromethorphan metabolism. These results indicate that dextromethorphan and bufuralol metabolism may be catalysed by CYP2B and not CYP2D. 相似文献
992.
Friis H Kaestel P Nielsen N Simonsen PE 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2002,96(2):151-156
Based on a cross-sectional study conducted among 100 adults in 1993 in Tanga, Tanzania, the relationship between Wuchereria bancrofti infection and markers of iron, vitamin A and vitamin E status was assessed. Potential predictors assessed were elephantiasis, hydrocoele, W. bancrofti microfilaria intensity and antigen concentration, and intensity of Schistosoma haematobium, hookworm, Trichuris trichiura and Ascaris lumbricoides infection, while controlling for age, sex and elevated serum alpha-1 antichymotrypsin. Of the 100 adults, 62 had W. bancrofti antigenaemia and 43 microfilaraemia, and 21 had elephantiasis. Of the 64 males, 31 had hydrocoele. W. bancrofti microfilaria intensity was a positive predictor of serum ferritin and a negative predictor of serum alpha-tocopherol. In contrast, negative relationships observed between W. bancrofti microfilaria intensity and serum beta-carotene and retinol were not significant. Neither antigen concentration nor clinical manifestations were predictors of micronutrient status. Intensity of hookworm infection was associated with lower serum ferritin. S. haematobium egg output was not a significant predictor of serum ferritin, but was a positive predictor of serum beta-carotene. In conclusion, W. bancrofti microfilaria intensity was associated with higher serum ferritin, but lower serum alpha-tocopherol. The associations probably reflect increased oxidative stress due to microfilariaehost interactions, which could play a role in the pathogenesis. 相似文献
993.
Patients (N = 199) referred to cardiac outpatient investigation because of chest pain were assessed with the Personality Diagnostic Questionnaire (PDQ-4). Thirty-nine percent scored positive for any personality disorder. Borderline and avoidant personality disorders were found significantly more often in patients with panic disorder (PD) (n = 72) than in patients without PD (12.5% vs. 2.5%, 23.7% vs. 7.7%, respectively). In PD patients, the presence of any personality disorder was significantly associated with higher scores of self-reported anxiety-agoraphobia symptoms, neuroticism, and the presence of suicidal thoughts. These results suggest that personality pathology is important in a subgroup of patients presenting with chest pain and that these patients may require more extensive treatment. 相似文献
994.
The prevalence of non-fearful panic disorder (panic attacks without the experience of fear) was estimated in 199 patients consecutively referred to outpatient cardiac investigation for chest pain. Fifty-nine patients met the criteria for panic disorder, and 17 patients fulfilled the criteria for non-fearful panic disorder. The patients with non-fearful panic disorder had lower scores on self-reported panic symptoms and lower frequencies of agoraphobia and comorbid axis I disorders than the patients with panic disorder and had a higher prevalence of somatic disorders than the patients without panic disorder. The patients with non-fearful panic disorder did not differ significantly from the patients with panic disorder in health-related quality of life. 相似文献
995.
Pendred's syndrome. Acoustic, vestibular and radiological findings in 17 unrelated patients 总被引:2,自引:0,他引:2
T Johnsen C Larsen J Friis F Hougaard-Jensen 《The Journal of laryngology and otology》1987,101(11):1187-1192
Seventeen unrelated Danish patients with Pendred's syndrome, whose case stories have not been published previously, are presented. Acoustic and vestibular functions were examined and endocrinological screening was performed. There was a great variation in hearing ability as well as in thyroid function. Furthermore, in contrast to previous investigations, normal caloric function was demonstrated in the majority. In all patients a Mondini malformation was demonstrated. On the basis of this investigation it is concluded that: (1) the Mondini defect is part of Pendred's syndrome; (2) the inherited Mondini malformation is the underlying cause of the sensorineural hearing impairment; and (3) the hearing sensitivity varies greatly in these patients. 相似文献
996.
Cell shrinkage as a signal to apoptosis in NIH 3T3 fibroblasts 总被引:4,自引:0,他引:4
Martin B. Friis Christel R. Friborg Linda Schneider Maj-Britt Nielsen Ian H. Lambert Søren T. Christensen Else K. Hoffmann 《The Journal of physiology》2005,567(2):427-443
Cell shrinkage is a hallmark of the apoptotic mode of programmed cell death, but it is as yet unclear whether a reduction in cell volume is a primary activation signal of apoptosis. Here we studied the effect of an acute elevation of osmolarity (NaCl or sucrose additions, final osmolarity 687 mosmol l−1 ) on NIH 3T3 fibroblasts to identify components involved in the signal transduction from shrinkage to apoptosis. After 1.5 h the activity of caspase-3 started to increase followed after 3 h by the appearance of many apoptotic-like bodies. The caspase-3 activity increase was greatly enhanced in cells expressing a constitutively active G protein, Rac (RacV12 A3 cell), indicating that Rac acts upstream to caspase-3 activation. The stress-activated protein kinase, p38, was significantly activated by phosphorylation within 30 min after induction of osmotic shrinkage, the phosphorylation being accelerated in fibroblasts overexpressing Rac. Conversely, the activation of the extracellular signal-regulated kinase (Erk1/2) was initially significantly decreased. Subsequent to activation of p38, p53 was activated through serine-15 phosphorylation, and active p53 was translocated from the cytosol to the nucleus. Inhibition of p38 in Rac cells reduced the activation of both p53 and caspase-3. After 60 min in hypertonic medium the rate constants for K+ and taurine efflux were increased, particular in Rac cells. We suggest the following sequence of events in the cell shrinkage-induced apoptotic response: cellular shrinkage activates Rac, with activation of p38, followed by phosphorylation and nuclear translocation of p53, resulting in permeability increases and caspase-3 activation. 相似文献
997.
998.
Boye M Jensen TK Ahrens P Hagedorn-Olsen T Friis NF 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2001,109(10):656-664
Oligonucleotide probes targeting 16S ribosomal RNA were designed for species-specific identification of the porcine mycoplasmas Mycoplasma hyopneumoniae, Mycoplasma hyorhinis and Mycoplasma hyosynoviae using a fluorescent in situ hybridisation assay. The specificity of the probes was evaluated using pure cultures as well as porcine tissue sections with artificial presence of mycoplasma, and the probes were found specific for the target organisms. The assay was applied on sections of 28 tissue samples from pigs infected with one or more of the three Mycoplasma species as determined by cultivation. M. hyopneumoniae and M. hyorhinis were identified in accordance with cultivation in lung sections from nine pigs affected by catarrhal to purulent bronchopneumonia. Likewise, in eight cases of fibrinous pericarditis, M. hyopneumoniae, M. hyorhinis and M. hyosynoviae were the infectious agents according to cultivation and were correctly identified by in situ hybridisation. Out of 11 joints cultivation positive for M. hyosynoviae, the probe was only able to identify M. hyosynoviae in eight cases probably due to a low number of microorganisms in the tissue sections. The in situ hybridisation assay is well suited for use in diagnostic and experimental work as well as a tool for pathogenesis studies. 相似文献
999.
A temperature-sensitive mutant of Rous sarcoma virus that is defective for replication 总被引:3,自引:0,他引:3
ts 672 is a temperature sensitive mutant of the Prague strain of Rous sarcoma virus which fails to replicate infectious progeny virus at 41 °C. Chick embryo cells infected with ts 672 are transformed as evidenced by focus formation and increased rate of 2-deoxyglucose transport. Rescue of infectious progeny from ts 672-infected cells at 41 °C can be obtained by superinfection with avian leukosis viruses. Avian tumor virus group specific and type specific antigens can be detected in chick embryo cells infected with ts 672 at 41 °C, and physical particles that incorporate 3H-uridine and cosediment with avian tumor viruses on sucrose density gradients are produced in large numbers. 相似文献
1000.
H. Friis P. Ndhlovu T. Mduluza K. Kaondera D. Franke B. Jyding Vennervald N. Ornberg Christensen E. Doehring 《Tropical medicine & international health : TM & IH》1996,1(2):183-190
Attempts have been made to develop a staging system of sonographic Schistosoma mansoni morbidity for use in epidemiological studies and for evaluation of control programmes. Therefore, normal dimensions of livers and spleens in children in countries with endemic S. mansoni infections need to be established. Normal dimensions of livers and spleens are presented, based on examination of 144 Zimbabwean children between 8 and 16 years of age found to be S. mansoni egg negative 12 months after treatment with praziquantel. Based on the liver and spleen measurements, an index of liver size and the spleen volume were calculated. Height was employed as the independent variable in all multiple regression models. The organometric data are presented as prediction plots, with observed values and fitted regression line with 95% confidence and prediction intervals. The mean spleen volume was 30% larger for boys than for girls, whereas there was no consistent difference in liver size. No effect of growth Z-scores was seen. The measurements were compared with normal dimensions of livers of German children. For a given height, the mean index of liver size was lower in Zimbabwean than in German children, but inter-observer variation could be a possible explanation for this difference. 相似文献