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排序方式: 共有1565条查询结果,搜索用时 31 毫秒
1.
D J Brooks J S Gibbs P Sharp S Herold D R Turton S K Luthra E M Kohner S R Bloom T Jones 《Journal of cerebral blood flow and metabolism》1986,6(2):240-244
Regional cerebral [11C]3-O-methyl-D-glucose ([11C]MeG) uptake kinetics have been measured in five insulin-dependent diabetic patients and four normal controls using positron emission tomography (PET). Concomitant measurement of regional cerebral blood volume and CBF enabled corrections for the presence of intravascular [11C]MeG signal in cerebral regions of interest to be carried out, and regional cerebral [11C]MeG unidirectional extraction fractions to be computed. Four of the five diabetic subjects were studied with their fasting plasma glucose level clamped at a normoglycaemic level (4 mM), and four were studied at hyperglycaemic plasma glucose levels (mean 13 mM). The four diabetic subjects whose fasting plasma glucose levels were clamped at a normoglycaemic level of 4 mM had mean fasting whole-brain, cortical, and white matter [11C]MeG extraction fractions of 15, 15, and 16%, respectively, values similar to those found for the four normal controls (whole brain, 14%; cortex, 13%; white matter, 17%). Mean regional cerebral [11C]MeG extraction fractions were significantly reduced in diabetic subjects during hyperglycaemia whether their plasma insulin levels were undetectable or whether they were raised by continuous intravenous insulin infusion. Such a reduction in [11C]MeG extraction under hyperglycaemic conditions can be explained entirely in terms of increased competition between [11C]MeG and D-glucose for the passive facilitated transport carrier system for hexoses across the blood-brain barrier (BBB). It is concluded that the number and affinity of D-glucose carriers present in the BBB are within normal limits in treated insulin-dependent diabetic subjects. In addition, insulin appears to have no effect on the transport of D-glucose across the BBB. 相似文献
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A Herold 《Der Chirurg》2006,77(8):737-47; quiz 748
Hemorrhoidal disease is one of the most frequent disorders in western countries. The aim of individual therapy is freedom from symptoms achieved by normalisation of anatomy and physiology. Treatment is orientated to the stage of disease: haemorrhoids 1 are treated conservatively. In addition to high-fibre diet, sclerotherapy is used. Haemorrhoids 2 prolapse during defecation and return spontaneously. First-line treatment is rubber band ligation. Haemorrhoids 3 that prolapse during defecation have to be digitally reduced, and the majority need surgery. For segmental disorders, haemorrhoidectomy according to Milligan-Morgan or Ferguson is recommended. In circular disease, Stapler hemorrhoidopexy is now the procedure of choice. Using a therapeutic regime according to the hemorrhoidal disease classification offers high healing rates and low rates of complications and recurrence. 相似文献
4.
The authors investigated whether graduating students' specialty choices were influenced by favorable faculty evaluations and mini-Board scores during their third-year clerkships, and if so, whether the influences were gender-specific. Data were collected from a total of 53 students in two classes, 1988-89 and 1988-90. Univariate and multivariate tests were performed, and the results were analyzed between each class group and between genders in both groups. These results also were compared with information about the students gathered before they matriculated. In general, the results showed a gender-specific correlation: for each rotation where the women's faculty evaluations were significantly higher than the men's, the women subsequently outnumbered the men in choosing that rotation's specialty. Conversely, for each rotation where the men's mini-Board scores were significantly higher than the women's, the men outnumbered the women in choosing that rotation's specialty. The most notable difference was in pediatrics: 8% of the women had indicated an interest in that specialty on the prematriculation questionnaire, while almost one-third of the women in the classes of 1990 and 1991 chose pediatrics residencies. These findings suggest that the favorable scores and evaluations may be one of the influences for students' specialty choices, and that their influence may be gender-specific. 相似文献
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Pneumonia is one of the leading causes of morbidity, hospitalization, and mortality in both industrialized and developing countries. In particular, pulmonary infections acquired in the community, and pneumonias arising in the hospital setting, represent a major medical and economic problem and thus a continuous challenge to health care. For the radiologist, it is important to understand that community-acquired pneumonia (CAP) and nosocomial pneumonia (NP) share a number of characteristics, but should, in many respects be regarded as separate entities. CAP and NP arise in different populations, host different spectra of causative pathogens, and pose different challenges to both the clinician and the radiologist. CAP is generally seen in outpatients, is most frequently caused by Streptococcus pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, and Chlamydia, and its radiologic diagnosis is relatively straightforward. NP, in contrast, develops in the hospital setting, is commonly caused by gram-negative bacteria, and may generate substantial problems for the radiologist. Overall, both for CAP and NP, imaging is an integral component of the diagnosis, important for classification and differential diagnosis, and helpful for follow-up. 相似文献
7.
R G Roetzheim D J Van Durme H J Brownlee A H Herold R J Pamies L Woodard 《The Journal of the Florida Medical Association》1991,78(7):426-429
A survey of primary care physicians in the greater Tampa Bay metropolitan area was conducted to determine compliance with screening mammography and associated physician characteristics. Information requested included their age, sex, specialty, and board certification status, and the ages and frequencies that they recommend screening mammography for their patients. A total of 565 physicians responded. Even though 88% indicated they follow American Cancer Society recommendations when advising screening mammography, only 62% were actually in full compliance. A significantly greater percentage of obstetricians/gynecologists were compliant (74%) compared to other specialties (family practice, 57%, p = .006; internal medicine, 56%, p = .007; general practice, 53%, p = .003). Women physicians were more likely to be compliant than men (83% versus 58%, p less than .001), and younger physicians more likely than older physicians (72% versus 49%, p less than .001). There was no significant difference in compliance rates between board certified and noncertified physicians. 相似文献
8.
Trauma und Berufskrankheit - In der überwiegenden Anzahl der Patienten mit posttraumatischen Fehlbildungen der Wirbelsäule geben Schmerzen Anlass zu einem Korrektureingriff. Die Ursachen... 相似文献
9.
Enhancement of antigen-presenting ability of B lymphoma cells by partial inhibition of protein synthesis through inducing B7-1 expression. 总被引:1,自引:1,他引:0
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D Nachbaur M Herold B Eibl H Glassl H Schwaighofer C Huber A Gchter M Pichl D Niederwieser 《Immunology》1997,90(2):212-218
During the investigation of the role of protein synthesis in antigen-presenting cell (APC) function of A20-HL B lymphoma cells, we found that partial inhibition of protein synthesis enhanced their APC function. The treatment of A20-HL cells with 0.313-2.5 microM emetine, an irreversible inhibitor of protein synthesis, decreased protein synthesis by 60-70%, and enhanced their APC function to stimulate I-Ad/OVA323-339-specific T cells to produce interleukin-2 in response to ovalbumin (OVA). The emetine-treated and paraformaldehyde-fixed A20-HL cells required only 20 nM OVA323-339 peptide to stimulate the T cells, whereas those untreated and fixed required 200 nM peptide. This enhancement of APC function was mostly because of the induction of B7-1 expression on A20-HL cells by the emetine treatment, since B7-1 molecules were detected on the emetine-treated A20-HL cells, but only negligibly, if at all, on the untreated cells, and an anti-B7-1 monoclonal antibody, 1G10, inhibited the enhanced APC function of the emetine-treated A20-HL cells. The emetine-treatment also increased B7-1 mRNA expression in A20-HL cells, suggesting that the induction of B7-1 expression was due to the increase in the accumulation of mRNA and the translation with residual ability to synthesize protein. Thus, partial inhibition of protein synthesis in A20-HL cells increases B7-1 mRNA accumulation and its expression on the cell surface, which results in the enhancement of their APC function. 相似文献
10.
P O Greiner P Charles M Bonnet D Angignard J M Dupont M Herold M G Borzeix C M Bonnet 《Neurobiology of aging》1992,13(4):527-529
After evaluation of activity in an open field, norepinephrine (NE), serotonin (5HT), 5-hydroxyindolacetic acid (5HIAA), homovanillic acid (HVA), and choline acetyltransferase (CAT) were investigated in cortex of 26-month-old rats poisoned with methylazoxymethanol (MAM) as compared to control rats of the same age. NE and 5HT concentrations showed a marked increase, but levels were normal when expressed as total content, just as in MAM-exposed young adults. Concentrations of 5HIAA were also increased but to a lesser extent than 5 HT. Aged MAM rats did not show any modification of spontaneous activity although hyperactivity is characteristic of young adults exposed to MAM. Together with this behavioral observation, a significant decrease in total HVA content was measured. Because HVA levels seem correlated with activity in MAM-exposed rats, we speculate that the behavioral abnormality recovers in old age. Total CAT activity was also reduced. These results indicate that the neurochemical pattern of young adult MAM-poisoned rats is conserved in aged rats except for some changes in the dopaminergic and cholinergic systems. 相似文献