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121.
Benjamin H. Natelson Walter N. Tapp Jean E. Adamus James C. Mittler Barry E. Levin 《Physiology & behavior》1981,26(6):1049-1054
Rats, bearing chronic venous cannulas, were subjected to 30 sec of constant current grid shock at 1 of 6 intensities (0, 0.25, 0.5, 1, 2, 4 mA), after being allowed to acclimate to the test chamber overnight. Blood, sampled before and after shock, was assayed for epinephrine, norepinephrine and corticosterone. Peak levels of both catecholamines increased in a stepwise fashion (i.e., monotonically) with increasing magnitude of stress, as reflected by current intensity of foot shock. Plasma corticosterone did not increase monotonically but instead showed similar increases in the 5 groups of rats that actually received shock. These data support earlier work which indicate that plasma corticosterone is not a sensitive index of stress; this is probably the case because of the relatively narrow range of responsiveness of the adrenal cortex to ACTH. In contrast, both plasma catecholamines appear to satisfy some of the requisites for a sensitive visceral index of stress. 相似文献
122.
Boss JH Misselevich I Peskin B Zinman C Levin D Norman D Reis DN 《Journal of comparative pathology》2003,129(2-3):235-239
The femoral heads of 15 rats were studied histologically 3 months after the induction of ischaemic necrosis by incising the cervical periosteum and cutting the ligamentum teres. The epiphyses consisted of immature disorganized subchondral and trabecular bone. The inter-trabecular spaces contained fibrous or haematopoietic tissue. Residual necrotic bone was rare. There was marked osteoblastic and osteoclastic activity. The articular aspect of the heads showed a spectrum of changes, ranging from cartilaginous degeneration with fibrillation and loss of glycosaminoglycans to an eburnated and polished bony surface. In seven rats, transphyseal bridges connected the epiphyseal and metaphyseal bony trabeculae to each other. It is suggested that the postnecrotic reparative processes, including the resorption of the necrotic debris and its replacement by newly formed, weak bone, led to an osteoarthritis-like disorder. This healing pattern of the necrotic femoral head was reminiscent of the progressive remodelling that occurs in rings in femoral capital osteonecrosis of adult human patients and in Perthes's disease of children. 相似文献
123.
Base and stress levels of corticosterone were assessed at 4-h intervals over a 24-h period in male and female rats at age 18, 22, and 26 days. A significant periodicity in base levels of corticosterone is present at 22 days of age; however, a rhythm in stress values does not appear until age 26 days. At age 26 days the pattern of the circadian periodicity in both base and stress concentrations of corticosterone resembles that of the mature rhythm. 相似文献
124.
Aikens JE Michael E Levin T Myers TC Lowry E McCracken LM 《Journal of behavioral medicine》1999,22(6):605-617
Although comparative studies differentiate noncardiac chest pain (NCCP), panic disorder, and coronary artery disease (CAD), little research has examined the defining features of NCCP, such as cardiac complaints, medical utilization, and learning history. We administered self-report measures to 80 Emergency Department (ED) patients with a primary complaint of chest pain who were subsequently found to not have CAD. Forty-eight percent of the ED utilization variance was accounted for by NCCP duration, age, cardiac distress symptoms, and prior exposure to both siblings' and friends' cardiac distress symptoms. In turn, 67% of the variance in cardiac distress symptoms was explained by education, age, NCCP duration, number of illnesses, noncardiac panic symptoms, prior exposure (friends), and prior observation of others' cardiac distress. No effects emerged for gender, ethnicity, avoidance, or depression. Results suggest that beyond the effects of age and distress intensity, prior exposure to other people's cardiac distress may influence NCCP. 相似文献
125.
IgA, IgG, IgM, and IgE levels in healthy, non-atopic, Israeli-born children aged 20 days to 16 years were analyzed and showed similar age-related values and dynamics as those of white populations found in other countries. No significant effect of sex of the individual or ethnic origin of the parents was found on the IgE values at different ages. This may indicate that total IgE levels are strongly influenced by environmental factors. Establishing tolerance limits at 97.5, 95, 75, 25 and 5th percentiles and the geometric mean provides the practitioner with more complete reference values. The use of multivariate control charts with tolerance limits from normal IgA, IgG, IgM, and IgE levels is described and is offered as an additional tool for the diagnosis of an allergic individual. 相似文献
126.
Cloning and developmental expression analysis of the murine homolog of the spinocerebellar ataxia type 1 gene (Sca1) 总被引:2,自引:0,他引:2
Banfi S; Servadio A; Chung M; Capozzoli F; Duvick LA; Elde R; Zoghbi HY; Orr HT 《Human molecular genetics》1996,5(1):33-40
Spinocerebellar ataxia type 1 (SCA1) is an autosomal dominant
neurodegenerative disorder caused by the expansion of a CAG trinucleotide
repeat which encodes glutamine in the novel protein ataxin-1. In order to
characterize the developmental expression pattern of SCA1 and to identify
putative functional domains in ataxin-1, the murine homolog (Sca1) was
isolated. Cloning and characterization of the murine Sca1 gene revealed
that the gene organization is similar to that of the human gene. The murine
and human ataxin-1 are highly homologous but the CAG repeat is virtually
absent in the mouse sequence suggesting that the polyglutamine stretch is
not essential for the normal function of ataxin-1 in mice. Cellular and
developmental expression of the murine homolog was examined using RNA in
situ hybridization. During cerebellar development, there is a transient
burst of Sca1 expression at postnatal day 14 when the murine cerebellar
cortex becomes physiologically functional. There is also marked expression
of Sca1 in mesenchymal cells of the intervertebral discs during development
of the spinal column. These results suggest that the normal Sca1 gene, has
a role at specific stages of both cerebellar and vertebral column
development.
相似文献
127.
JE Robb LA Rymaszewski HB Bentley PT Donnan 《Surgical and radiologic anatomy : SRA》1991,13(3):181-185
Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.
La valeur du sourcil cotyloidien comme repère d'analyse radiologique
Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.相似文献
128.
129.
A. PIONA L. LA ROSA A. TINCANI D. FADEN† G. MAGRO‡ S. GRASSO‡ F. NICOLETTI G. BALESTRIERI P. L. MERONI 《Scandinavian journal of immunology》1995,41(5):427-432
In the present study we evaluated the effect of passive transfer of a mouse monoclonal (CAM) or a human polyclonal anti-cardiolipin IgG on pregnancy outcome in BALB/c mice. The mice were immunized through the tail vein immediately after mating with 10 μg of monoclonal or polyclonal anti-cardiolipin antibodies. Two other groups of mice were given a mouse irrelevant monoclonal antibody or normal human polyclonal IgG respectively, at the same dose. In mice immunized with monoclonal or polyclonal anti-cardiolipin antibody we observed a significant increase in the number of fetal resorptions and a significant reduction of the mean weights of the embryos and the placentas. In mice immunized with CAM we also found a significant decrease in the number of healthy pups, while mice infused with human aCL antibody expressed a significant reduction in the fecundity rate. The histological examination showed widespread thrombosis and necrosis in the placentas derived from the mice immunized with the anti-cardiolipin antibodies. The model supports a possible direct pathogenetic effect of anti-phospholipid antibodies in recurrent fetal loss and points out that thrombotic events at placental level can be instrumental in the pathogenesis of the obstetric complications. 相似文献
130.