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91.
A highly selected group of patients younger than 50 years of age operated on for isolated aorto-iliac arteriosclerotic disease over a 7 year period has been investigated. The group has a significant dominance of females, and the patients are further characterised by being apparently otherwise "healthy" individuals. The indication for surgery was intermittent claudication in 80% and rest pain/gangrene in the remainder, with a low postoperative morbidity and no mortality. The overall cumulative patency rate is 89% at 4 years. At follow-up, a large majority of the patients were free of symptoms and the long-term results were significantly better in females. The question arises whether our group of patients, especially the young females with isolated aorto-iliac arteriosclerotic lesion, represent a separate disease entity which, when properly treated, is a benign and curable condition.  相似文献   
92.
Cadmium toxicity and uptake as influenced by different pH values have been studied in the freshwater cyanobacteriumAnabaena flos-aquae, using the techniques of morphometric analysis, x-ray energy dispersive analysis and atomic absorption spectrophotometry. A general reduction in cell dimension, thylakoid surface area, number and volume of polyhedral bodies, polyphosphate bodies, cyanophycin granules, lipid bodies, membrane limited crystalline inclusions, volume and number of wall layers and mesosomes was observed. These reductions were more pronounced in both acidic and alkaline medium than at pH 7.2. At 0.12 M Cd, the uptake increased with alkaline pH values, and uptake was greater at pH 7.2 than at either acid or alkaline pHs. Lysis of cell wall at 1.18 M Cd showed the following decreasing trend: pH 4.0 > pH 5.5 > pH 10.0 > pH 9.0 > pH 7.2. There was a total loss of lipid bodies at 1.18 M Cd at all pH values listed.It is suggested that these techniques can be successfully employed for bioassay studies of metal toxicity to algae. In particular, cell wall lysis and loss of lipids by algae are good indicators of pH effects and metal toxicity in the aquatic ecosystem.  相似文献   
93.
Serine proteinase inhibitors (serpins) are well known regulators of extracellular proteolytic pathways. A recently identified group of intracellular serpins of mammalian and viral origin, designated ovalbumine-like serpins, modify intracellular proteolytic pathways involved in the regulation of apoptosis and inflammation. This review focuses on plasminogen activator inhibitor-2 (PAI-2) in terms of the molecular structure-function relationships and its intracellular functions, in particular in relation to apoptosis. PAI-2 inhibits apoptosis in cell lines challenged with tumor necrosis factor or certain viruses. The intracellular proteinases which PAI-2 act upon are still unknown. During myeloid apoptosis, PAI-2 proteolytically modified to a smaller but still proteinase inhibitory form. PAI-2 is unique among the serpins with respect to its large CD-domain localized between alpha-helices C and D. Recent data show that two domains in PAI-2 are required for its antiapoptotic activity, the CD-domain and the proteinase reactive site. We have shown the CD-domain is involved in covalent and reversible interactions with cytosolic proteins, e.g. the annexins. These intracellular PAI-2-reactive proteins might represent participants in signalling pathways involved in the regulation of cell survival.  相似文献   
94.
This article examines the connection between pornography and violence against women through interviews with men about pornography use. It emphasizes the value of narrative accounts as important sources of information over experimental laboratory research. The narratives described in this article give specific examples of how pornography can 1) be an important factor in shaping a male-dominant view of sexuality; 2) contribute to a user's difficulty in separating sexual fantasy and reality; 3) be used to initiate victims and break down their resistance to sexual activity; and 4) provide a training manual for abusers. The subjects in this study were divided into two groups: 11 men who responded to a classified ad that asked for male interview subjects and 13 residents of the Alpha Human Services sex offender treatment program. The interviews documented in this article focus on cases where there is a clear link between pornography use and abuse. Analysis of the interviews provides support for the feminist anti-pornography critique.  相似文献   
95.
Severe destructive Lyme arthritis was detected in the hind paws of hamsters infused with enriched populations of either CD4+ or CD4- T lymphocytes along with macrophages exposed in vitro to formalin-inactivated Borrelia burgdorferi and then infected with the Lyme spirochete. Swelling was detected 4 days after infection, increased rapidly, peaked on day 8 of infection, and gradually decreased. Similarly, severe destructive arthritis was induced in hamsters infused with enriched populations of unfractionated T lymphocytes and macrophages exposed to spirochetes after infection with B. burgdorferi. Histopathological examination affirmed that hamsters infused with CD4+, CD4-, or unfractionated T lymphocytes and macrophages exposed to B. burgdorferi-induced arthritis. In addition, macrophages exposed in vitro to B. burgdorferi demonstrated both conventional and coiling phagocytosis, suggesting a mechanism by which CD4+ and CD4- T lymphocytes induce arthritis, respectively. These findings demonstrate that both CD4+ and CD4- subpopulations of T lymphocytes are capable of interacting with macrophages for the induction of severe destructive Lyme arthritis.  相似文献   
96.
The phenotypic expression of haemolysins and the presence of genes encoding alpha and beta-haemolysin were determined in 105 Staphylococcus aureus isolates from bovine mastitis, 100 isolates from the nostrils of healthy humans, and 60 isolates from septicaemia in humans. Furthermore, the possible change in expression of haemolysins after subcultivation in human and bovine blood and milk was studied in selected isolates. Alpha-haemolysin was expressed phenotypically in 39 (37%) of the bovine isolates, in 59 (59%) of the human carrier isolates, and in 40 (67%) of the isolates from septicaemia. Beta-haemolysin was expressed in 76 (72%) bovine, 11 (11%) carrier, and 8 (13%) septicaemia isolates. Significantly more bovine than human isolates expressed beta-haemolysin and significantly fewer expressed alpha-haemolysin. Genotypically, the gene encoding alpha-haemolysin was detected in all isolates. A significant difference in the prevalence of the gene encoding beta-haemolysin between the bovine (96%), human carrier (56%) and isolates from septicaemia (57%) was found. Of the bovine isolates, 75% of those carrying the gene encoding beta-haemolysin expressed beta-haemolysin phenotypically, whereas only 20% of the carrier isolates and 24% of the septicaemia isolates did so. No change in expression of haemolysins could be observed after subcultivation of bovine isolates in human blood and milk. After 5 to 10 subcultures in bovine blood and 1 to 4 in bovine milk, 9 of 10 human isolates originally phenotypically beta-haemolysin negative initiated the expression of beta-haemolysin. This study showed that a larger proportion of S. aureus of bovine origin carry the beta-haemolysin gene compared to isolates from humans. Furthermore, a larger number of the isolates of bovine origin carrying the beta-haemolysin gene express this gene phenotypically compared to isolates of human origin.  相似文献   
97.
98.
There has been only one previous report of an intracardiac gastrinoma causing Zollinger-Ellison syndrome. In this communication we describe the successful surgical resection of a gastrinoma located in the interventricular septum using cardiopulmonary bypass, blood cardioplegia, and mild hypothermia. Preoperative evaluation and histologic examination of the resected tumor strongly suggest that this was a primary intracardiac gastrinoma.  相似文献   
99.
Certain neurochemical and connectional characteristics common to extended amygdala and the nucleus accumbens shell suggest that the two represent a single functional-anatomical continuum. If this is so, it follows that the outputs of the two structures should be substantially similar. To address this, projections from the caudomedial shell and central nucleus of the amygdala, a key extended amygdala structure, were demonstrated in Sprague-Dawley rats with different anterograde axonal tracers processed separately to exhibit distinguishable brown and blue-black precipitates. The caudomedial shell projection is strong in the ventral pallidum and along the medial forebrain bundle through the lateral preopticohypothalamic continuum into the ventral tegmental area, distal to which it thins abruptly. The central nucleus projects strongly to the bed nucleus of the stria terminalis and the sublenticular extended amygdala, but substantially to the lateral hypothalamus only at levels behind the rostral part of the entopeduncular nucleus. Innervation of the ventral tegmental area by the central amygdala is minimal, but the lateral one-third of the substantia nigra, pars compacta and an adjacent lateral part of the retrorubral field receive substantial central amygdala input. Central amygdaloid projections are robust in caudal brainstem sites, such as the reticular formation, parabrachial nucleus, nucleus of the solitary tract and dorsal vagal complex, all of which receive little input from the accumbens. The substantial differences in the output systems of the caudomedial shell of accumbens and central amygdala suggest that the two represent distinct functional-anatomical systems.  相似文献   
100.
The aim of this study was to investigate the internal and external validity of the Whiteley Index as a screening instrument for somatization illness. A 14-item version of the Whiteley Index for hypochondriacal traits was given to 99 of 191 consecutive primary care patients, aged 18-65 years, and to 100 consecutive patients, aged 18-60 years, admitted for the first time to a neurological ward. The primary care sample was, in addition, interviewed by means of the SCAN (Schedules for Clinical Assessment in Neuropsychiatry) psychiatric interview. The GPs and the neurologists were asked to rate various characteristics of the patients that might indicate somatization. The internal validity of the Whiteley Index was tested by means of latent structure analysis. On this basis, a reduced seven-item scale (Whiteley-7 scale) and two subscales (i.e., an Illness Conviction and Illness Worrying scale, each with three items) were constructed. All three had a high internal validity fitting into the very restricted Rasch statistical model (p>0.05) and an acceptable transferability between most of the subpopulations investigated. In the primary care population, the Whiteley-7 and the Illness Conviction scales at cut-point 0/1 showed 1.00 and 0.87 sensitivity and 0.65 and 0.87 specificity, respectively, using as "gold standard" the fulfillment of criteria for at least one ICD-10 somatoform disorder, and 0.71 and 0.63 sensitivity and 0.62 and 0.87 specificity, respectively, as gold standard for the fulfillment of criteria for at least one DSM-IV somatoform disorder, excluding the NOS diagnostic group. The Illness Worrying subscale showed less impressive performance in this respect. The agreement between the Whiteley-7 scale including the two subscales and neurologists' rating and the GPs' rating and the somatization subscale on the SCL-90 was modest or worse. It may be concluded that the Whiteley-7 scale and the Illness Conviction subscale had acceptable psychometric profiles, and both seem to be promising screening tools for not only hypochondriasis but also for somatoform disorders in general.  相似文献   
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