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21.
Summary 20 male elite long distance runners were compared to a control group of blood donors to determine the effect of training on red blood cells. The acute effects of exercise on red cells were investigated in 11 of the runners following a race of 15–30 km. The runners had elevated resting values of red cell 2,3-DPG (P<0.05) and mean cell volume (P<0.01); blood Hb and ATP were not different from concentrations in the control group. The red cell status of the athletes may be explained by an increased proportion of young erythrocytes in runners. No statistically significant changes in red cell 2,3-DPG, ATP, mean cell volume or blood Hb were found post exercise.  相似文献   
22.
A case is reported of an apparent total erythrocyte adenosine deaminase (ADA) deficiency in a girl suffering from severe combined immunodeficiency (c.i.d.). Four other erythrocyte enzymes investigated showed apparent normal activity. The ADA activity in erythrocytes from her parents was about half normal, suggesting that the girl had inherited a chromosome pair without information for normal red cell ADA-isoenzymes. The suspected chromosome deficit may have affected the ADA locus only, or it may involve a more extensive part of a chromosome including the ADA locus. In another child, a boy exhibiting clinically the same immunodeficiency syndrome, the ADA type and ADA activity were found to be normal. Recently, two other cases of lack of red cell ADA activity, both affecting girls with similar manifestations of immunological deficiency, have been reported from the U.S.A. (Giblett et al. 1972). These findings indicate that coexistence of a total lack of red cell ADA activity and some immunodeficiency syndromes may be a common condition.  相似文献   
23.
The recent identification of a novel clinical entity, the severe acute respiratory syndrome (SARS), the rapid subsequent spread and case fatality rates of 14-15% have prompted a massive international collaborative investigation facilitated by a network of laboratories established by the World Health Organization (WHO). As SARS has the potential of becoming the first pandemic of the new millennium, a global warning by the WHO was issued on 12 March 2003. The disease, which is believed to have its origin in the Chinese Guangdong province, spread from Hong Kong via international airports to its current worldwide distribution. The concerted efforts of a globally united scientific community have led to the independent isolation and identification of a novel coronavirus from SARS patients by several groups. The extraordinarily rapid isolation of a causative agent of this newly emerged infectious disease constitutes an unprecedented scientific achievement. The main scope of the article is to provide the clinician with an overview of the natural history, epidemiology and clinical characteristics of SARS. On the basis of the recently published viral genome and structural features common to the members of the coronavirus family, a model for host cell-virus interaction and possible targets for antiviral drugs are presented. The epidemiological consequences of introducing a novel pathogen in a previously unexposed population and the origin and evolution of a new and more pathogenic strain of coronavirus are discussed.  相似文献   
24.
25.
A region in the barn owl forebrain, referred to as the archistriatal gaze fields (AGF), is shown to be involved in auditory orienting behavior. In a previous study, electrical microstimulation of the AGF was shown to produce saccadic movements of the eyes and head, and anatomical data revealed that neurons in the AGF region of the archistriatum project directly to brainstem tegmental nuclei that mediate gaze changes. In this study, we investigated the effects of AGF inactivation on the auditory orienting responses of trained barn owls. The AGF and/or the optic tectum (OT) were inactivated pharmacologically using the GABAA agonist muscimol. Inactivation of the AGF alone had no effect on the probability or accuracy of orienting responses to contralateral acoustic stimuli. Inactivation of the OT alone decreased the probability of responses to contralateral stimuli, but the animals were still capable of orienting accurately toward stimuli on about 60% of the trials. Inactivation of both the AGF and the OT drastically decreased the probability of responses to 16–21% and, on the few trials that the animals did respond, there was no relationship between the final direction of gaze and the location of the stimulus. Thus, with the AGF and OT both inactivated, the animals were no longer capable of orienting accurately toward acoustic stimuli located on the contralateral side. These data confirm that the AGF is involved in gaze control and that the AGF and the OT have parallel access to gaze control circuitry in the brainstem tegmentum. In these respects, the AGF in barn owls is functionally equivalent to the frontal eye fields in primates.  相似文献   
26.
In a cross-sectional investigation of 116 patients with multiple sclerosis, the social and sparetime activities of the patient were assessed by both patient and his/her family. The assessments were correlated to physical disability which showed that particularly those who were moderately disabled suffered from severe psychosocial strain. The literature shows that the strain becomes even more severe in certain periods of progression of the disease with the result that psychosomatic conditions arise.  相似文献   
27.
This study examines the influence of external ear position on the auditory spatial tuning of single units in the superior colliculus of the anesthetized cat. Unit responses to broad-band stimuli presented in a free sound field were measured with the external ears in a forward symmetrical position or with one or the other ear turned 40 degrees to the side; the ears are referred to as contra- or ipsilateral with respect to the side of the recording site. Changes in the position of either ear modified the spatial tuning of units. The region of space from which a stimulus was most effective in activating a unit is referred to as the unit's "best area". Whenever the contralateral ear was turned to the side, best areas shifted peripherally and somewhat upward, roughly in proportion to the magnitude of the change in ear position. A turn of the ipsilateral ear to the side had more variable effects, but best areas generally shifted frontally. Best areas located between approximately 10 and 40 degrees contralateral when the ears were forward were least affected by changes in ipsilateral ear position. Changes in ear position also modified the maximum response rates of many units. Units with best areas located within approximately 20 degrees of the frontal midline when the ears were forward exhibited a pronounced decrease in responsiveness when either ear was turned. Units with more peripheral best areas tended to show no change or a slight increase in responsiveness. The influence of ear position on the directionality of the external ears was determined by mapping the cochlear microphonic response to tones or one-third-octave bands of noise before and after turning the ear. When the ears were forward, maximum interaural intensity differences (IIDs) were produced by high-frequency sound sources (greater than or equal to 20 kHz) located 20-40 degrees from the frontal midline and by lower frequency sources located further peripherally. The influence of ear position on the locations from which maximum IIDs were produced was similar to the influence of ear position on unit best areas. Changes in ipsilateral ear position had different effects on high- and low-frequency IIDs that were comparable with the effects of changes in ear position on frontally and peripherally located best areas, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
28.
Rune  Lindskov Lone  Knudsen 《Allergy》1983,38(3):161-165
Fourteen adults and 10 children with active atopic dermatitis entered this double blind cross-over study of oral disodium cromoglycate (DSCG) (adults 200 mg qid, children 100 mg qid) compared with placebo. Oral DSCG and placebo were given for 6 weeks in random order. According to the investigators' assessments of eczema, significant differences between active and placebo were found after 6 weeks' treatment, DSCG being favoured (P less than 0.05). No differences were detected in the investigators' assessment of lichenization and overall disease. No significant differences between the two treatments were demonstrated in the patients' assessments. Results from food allergic patients were similar to those from non-food allergic patients. Two patients reported possible side effects of arthralgia and urticaria respectively. There were no treatment effects on serum IgE values or any other laboratory data.  相似文献   
29.
Although loss of cholinergic neurons in the basal forebrain is considered a key initial feature in Alzheimer's disease (AD), changes in other transmitter systems, including serotonin and 5-HT2A receptors, are also associated with early AD. The aim of this study was to investigate whether elimination of the cholinergic neurons in the basal forebrain directly affects 5-HT2A receptor levels. For this purpose intraventricular injection of the selective immunotoxin 192 IgG-Saporin was given to rats in doses of either 2.5 or 5 μg. The rats were sacrificed after 1, 2, 4 and 20 weeks. 5-HT2A protein levels were determined by western techniques in frontal cortex and hippocampus. A significant 70% downregulation in frontal cortex and a 100% upregulation in hippocampus of 5-HT2A receptor levels were observed 20 weeks after the cholinergic lesion when using the highest dose of 192 IgG-Saporin. Our results show that cholinergic deafferentation leads to decreased frontal cortex and increased hippocampal 5-HT2A receptor levels. This is probably a consequence of the interaction between the serotonergic and the cholinergic system that may vary depending on the brain region.  相似文献   
30.
Hepatocyte activator inhibitor-1 (HAI-1) is a transmembrane serine protease inhibitor that regulates the conversion of latent to active hepatocyte growth factor (HGF). Studies supporting a role for the HGF pathway in prostate carcinogenesis prompted an analysis of HAI-1 expression in the prostate. Here we analyze the regulation of HAI-1 expression by androgen, oncogenic transformation, and cancer progression. Immunohistochemical analysis revealed that HAI-1 expression was restricted to prostate epithelium, where staining occurred primarily in basal and atrophic luminal epithelial cells. Compared to normal glands, HAI-1 expression was significantly increased in localized prostate cancer and was present in most prostate cancer metastases. HAI-1 protein expression levels were sensitive to androgen in normal epithelium but not in cancer. Although androgen did not increase HAI-1 protein expression levels in LNCaP cells, it decreased HAI-1 surface expression, consistent with previous data from our group (Martin DB, Gifford DR, Wright ME, Keller A, Yi E, Goodlett DR, Aebersold R, Nelson PS: Quantitative proteomic analysis of proteins released by neoplastic prostate epithelium. Cancer Res 2004, 64:347-355). HAI-1 overexpression in cancer was predictive of prostate-specific antigen recurrence (relative risk, 1.24). These results suggest that HAI-1 regulates the HGF Met axis on prostate epithelial cells and influences HGF mediated tumor invasion and metastasis.  相似文献   
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