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51.
52.
Summary In three consecutive cases of giant left sided paraclinoid aneurysms we employed an endovascular retrograde suction decompression technique in combination with intra-operative angiography. A double-lumen balloon catheter was placed in the left internal carotid artery by the transfemoral route. After balloon inflation and placement of a temporary clip distal to the aneurysm blood was aspirated and the aneurysm collapsed. Thus further dissection of the aneurysm could easily be achieved and clips could be placed. Afterwards real-time digital subtraction angiography was performed. Intra-operative angiography led to clip repositioning in all cases either due to a clip induced stenosis of the parent vessel, or because of incomplete aneurysm obliteration. Afterwards successful clipping could be confirmed in all cases. Outcome was excellent in one case, good in the other. The third case, extremely complicated by an accompanying craniopharyngioma, showed a satisfactory outcome, but presented new neurological deficits.  相似文献   
53.
Dorsal root ganglion cells with axons innervating the cat's knee joint via the medial articular nerve were retrogradely labelled with Fast blue. Neurokinin A-like immunoreactivity was found in 4.5 +/- 1.1% (mean +/- S.D. of 5 nerves and 695 cells) of the articular afferents. Colchicine treatment of the ganglia increased the percentage of immunopositive cells to 8.5 +/- 0.7% (mean +/- S.D. of 6 nerves and 554 cells) after 3-22 h. The diameter distribution of the immunopositive somata ranged from 20 to 50 microns with a maximum at 26-30 microns. Comparing the proportions of neurokinin A-immunopositive cells with those of substance P, it can be calculated on the basis of mRNA encoding that neurokinin A is synthetized in about half of the substance P-containing primary articular afferents.  相似文献   
54.
Five male and female rats per dose-group received 2,3,7,8-tetrabromodibenzo-p-dioxin (2,3,7,8-TBDD) once on the first day of the study. Doses of 10, 33, 100, or 300 micrograms 2,3,7,8-TBDD/kg body wt. and the vehicle control were administered by gavage. About 20% of 2,3,7,8-TBDD was excreted via feces. Severe body weight retardation was observed in the 100 and 300 micrograms/kg dose-groups. Most animals in the 300 micrograms/kg dose-group and the females receiving 100 micrograms/kg showed emaciation, rough coat and a poor health (wasting syndrome). Of the animals dosed with 300 micrograms/kg, 3 males and all females died. After 100 micrograms 2,3,7,8-TBDD/kg 3 females died. Measured 4 weeks after dosing, triiodothyronine (T3) was increased and thyroxin (T4) was reduced dose dependently in serum. A dose-dependent decrease in thymus weights was observed at necropsy and histological examinations showed that thymus and spleen were depleted of mature lymphocytes. An increase in liver-to-body weight ratio was observed in all dose-groups. The histological examination revealed hypertrophy of centrilobular hepatocytes in the liver of animals treated with 100 micrograms/kg, which was less severe at the 33 micrograms/kg dose. Hypertrophic hepatocytes were also detected in some animals at the lowest dose. Induction of enzyme activities of the mixed function oxidases ethoxycoumarin O-deethylase (ECOD), ethoxyresorufin O-deethylase (EROD) and aryl hydrocarbon hydroxylase (AHH) in liver tissue differed for each of the three enzymes. Two days after administration, enzyme activities were increased but did not differ substantially between dose-groups. Twenty-eight days after dosing the increase in activity after 10 micrograms/kg was largest and the EROD of the 100 micrograms/kg dose-group in females was close to that of the control. This inverse dose-response relationship may be due to impaired liver cell function at higher doses.  相似文献   
55.
Zusammenfassung Grundlagen: Der Zweck war es, die Anzahl der im Mammogramm entdeckten duktalen Carcinoma in situ (DCIS) und multizentrische Karzinome aufzudecken. Die verschiedenen Methoden der Biopsie werden diskutiert. Methodik: Rastermammographie (Fokus 0,3 mm) und hochaufl?sende Sonographie (7,5 bis 10 MHz) wurden bei Brustkrebspatientinnen eingesetzt. Ergebnisse: Der Zeitraum der aufgelisteten Patientinnen erstreckt sich über 20 Jahre. Die Zahl der DCIS hat in den letzten Jahren zugenommen und betr?gt nun 18%. Die Mammographie ist hoch sensitiv für Entdeckung von Mikrokalzifikationen. Die Spezifit?t ist gering. Schlu?folgerungen: Die Anzahl der entdeckten DCIS ist in den letzten Jahren besonders angestiegen und wird auch noch weiter bei Verbesserung der mammographischen Techniken ansteigen. Diese Studie wurde vom Ludwig-Boltzmann-Institut für radiologisch-physikalische Tumordiagnostik unterstützt.  相似文献   
56.
57.
Heart failure is a complex clinical syndrome. There is evidence for a genetic contribution to the pathophysiology of heart failure. Considering the fundamental role of neurohormonal factors in the pathophysiology and progression of cardiac dysfunction and hypertrophy, variants of genes involved in this system are logical candidate genes in heart failure. In this report, genetic polymorphisms of the major neurohormonal systems in heart failure will be discussed. Studies on polymorphisms of the renin-angiotensin-aldosterone system (RAAS), adrenergic receptor polymorphisms, endothelin (receptor) polymorphisms, and a group of miscellaneous polymorphisms that may be involved in the development or phenotypic expression of heart failure will be reviewed. Research on left ventricular hypertrophy is also included. The majority of genetic association studies focused on the ACE I/D polymorphism. Initial genetic associations have often been difficult to replicate, mainly due to problems in study design and lack of power. Promising results have been obtained with genetic polymorphisms of the RAAS and sympathetic system. Considering the evidence so far, a modifying role for these polymorphisms seems more likely than a role of these variants as susceptibility genes. Besides the need for larger studies to examine the effects of single nucleotide polymorphisms and haplotypes, future studies also need to focus on the complexity of these systems and study gene-gene interactions and gene-environment interactions.  相似文献   
58.
Using an experimental model of continuous endotoxin infusion, the effects of castration, testosterone and estrogen substitution on disseminated intravascular coagulation in male rats were investigated. Male rats which are not pretreated react in the same way to an endotoxin infusion as female animals, with an increase in free plasma hemoglobin, decrease of fibrinogen level, decrease of hematocrit and platelets and glomerular fibrin depositions. Different experimental groups of testectomized rats were pretreated with (i) 0.3 micrograms (pregnancy-conserving dose) or (ii) 30 micrograms ethinylestradiol (ovulation-suppression dose) or (iii) 250 mg testosterone. They were then compared to groups of animals treated with sesame oil as well as untreated group of rats. The pretreatment with testosterone and estrogens in the small-dose group had only an insignificant effect on the shock sequence. Only those animals which were treated with a high dose of estrogens showed a dramatic enhancement of their endotoxin sensitivity. It was also shown that in male animals an increased estrogen level might mediate a state of 'preparation', but testosterone does not 'prepare' castrated rats for the generalized Schwartzman reaction. The possible significance of enhancement of endotoxin toxicity by estrogens in explaining some pathophysiological characteristics of disseminated intravascular coagulation in pregnancy is discussed.  相似文献   
59.
A survey was conducted in early 1985 among 366 new mothers at 3 hospitals in Pinar del Rio, Cuba, to assess their level of health information regarding the care of newborns. The 11 study variables included breastfeeding, weaning, bathing the newborn, care of clothing and equipment for the baby, well baby visits, vaccination, accidents and safety, parent-child relations, sex education, and the puerperium. The level of information on these topics was generally low and was adequate only for breastfeeding. The information deficit was not related to urban or rural residence, parity, or educational level. The lack of knowledge of new mothers was attributed to the lack of motivation of health personnel at all levels to provide health education, inadequate use of existing information channels, and a lack of emphasis on health education within the general educational system.  相似文献   
60.
In the sick sinus syndrome, in sinu-atrial conduction defects or in atrial flutter or fibrillation a stress-adapted, frequency-adapted stimulation cannot be obtained by the processing of the atrial potential. Here one depends on partly extracardiac parameters which contain informations about the metabolic and stress situation, respectively. A survey of the parameters for a frequency-adapted stimulation discussed at present is given and a critical valuation of them is carried out. It is shown that all parameters up to now experimentally and clinically, respectively, tested are more or less problematic and that the way out of the difficulty most consist in deriving the controlled variable for a stress adapted stimulation rate from several parameters.  相似文献   
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