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101.
To search for possible evidence of a relationship between human cytomegalovirus and aortic diseases, we examined 41 aortic lesions excised at surgery and 16 aortic tissues obtained at autopsy for the presence of cytomegalovirus DNA, by use of polymerase chain reaction. Cytomegalovirus DNA was present in seven (88%) of eight lesions of inflammatory aortic diseases with periaortic fibrosis, five of six inflammatory aneurysms, and all of two aortic occlusive lesions with inflammation. Cytomegalovirus DNA was detected in 20 (61%) of 33 atherosclerotic aneurysms, whereas it was detected in only five (31%) of 16 autopsy samples that showed neither inflammation nor atherosclerosis. Thus the possibility that cytomegalovirus may play a role in the pathogenesis of inflammatory aortic diseases warrants further attention.  相似文献   
102.
103.
The aim of this study was to elucidate the vasodilator mechanisms of barbiturates. In helical strips of dog mesenteric artery, the effects of pretreatment with thiopentone and pentobarbitone on the contractions induced by KCl (2.0 x 10(-2) M) and norepinephrine (10(-5) M) in normal bathing fluid, and those induced by norepinephrine and caffeine (2.5 x 10(-2) M) in Ca(++)-free fluid were tested, and their effects on caffeine-induced contractions in skinned strips were also examined. Thiopentone, at concentrations over 10(-4) M, inhibited the KCl-induced contractions in normal bathing fluid and those induced by caffeine in Ca(++)-free fluid and, at concentrations over 3 x 10(-4) M, inhibited norepinephrine-induced contractions in normal and Ca(++)-free bathing fluids significantly. Pentobarbitone, at concentrations over 3 x 10(-4) M, inhibited KCl- and norepinephrine-induced contractions in normal bathing fluid significantly, whereas contractions in Ca(++)-free fluid induced by norepinephrine and caffeine were inhibited only by a high concentration (10(-3) M) of pentobarbitone. Caffeine-induced contractions of chemically skinned fibres were more susceptible to inhibition by thiopentone than by pentobarbitone. These results suggest that the vasodilator effect of thiopentone is mediated via its intracellular inhibitory effect and that, in contrast, the vasodilator effect of pentobarbitone can be attributed mainly to its Ca(++)-channel blocking action.  相似文献   
104.
In order to investigate whether a hypothalamic disorder cause hypogonadism in male prolactinomas, LH pulsatile secretion was studied in 13 male patients. Serum PRL levels ranged from 186 to 45,000 ng ml-1 before treatment, and all the tumors were macroadenomas. Reduced LH secretion was revealed in 5 of 13 patients, and FSH was reduced in 1 of 13. Serum testosterone (T) levels were lower than the normal limit in all the patients. HCG tests in 3 patients showed good responses, but the peak values of T were lower than those of normal men. LH pulsatilities were examined in 5 hyperprolactinemic patients before treatment, in 4 hyperprolactinemic patients after operation, and in 8 normoprolactinemic patients after operation and/or bromocriptine treatment. There was no significant difference of the mean LH values, the frequencies of LH pulses, and amplitudes among the hyperprolactinemic patients before operation (n = 5), the normoprolactinemic patients after operation (n = 8), and normal men (n = 7). From these results, it was evident that the hypothalamus and pituitary function of male prolactinomas were well preserved, in spite of higher serum PRL levels and larger tumor size than those reported in females. It is suggested that the main cause of hypogonadism in these patients is due to testicular dysfunction resulting from excessive serum PRL.  相似文献   
105.
SCG10 is a nerve growth factor (NGF)-inducible, neuron-specific protein whose expression is tightly correlated with axonal and/or dendritic growth. We have recently shown that the mRNA encoding SCG10 is expressed at significant levels in certain subsets of neurons in the adult rat brain, while its expression is undetectable or negligible in other non-neuronal tissues. Here we show that regional SCG10 mRNA expression in the adult mouse brain is comparable to that in the rat, however, in the hippocampus its expression profile is distinct. In the mouse, SCG10 mRNA is expressed at high levels in pyramidal cells of CA3–CA4 sub-fields of Ammon's horn and at low levels in the CA1–CA2 sub-fields, while it is found rather uniformly throughout the pyramidal cell layer of the rat hippocampus. SCG10 mRNA is not detectable in the dentate gyrus of the mouse hippocampus, although it is expressed in the rat dentate gyrus. Comparison with other mRNAs encoding neuronal growth-associated proteins (nGAPs) such as GAP-43, MAP2, α1-tubulin and stathmin suggests that dentate granule cells express a different repertoire of neuronal growth-associated genes in mouse and rat.  相似文献   
106.
Interhemispheric cysts, often associated with agenesis of the corpus callosum, are rare lesions demonstrating little uniformity of pathogenesis. Four large interhemispheric cystic lesions with several unique features are reviewed. Magnetic resonance imaging clearly showed agenesis of the corpus callosum and was useful in the diagnosis of interhemispheric cysts. The differential diagnosis of these lesions is discussed, along with therapeutic considerations.  相似文献   
107.
Amygdaloid-kindled rats received intravenous human copper-zinc superoxide dismutase (CuZn-SOD) either in free form or entrapped within liposomes (SOD-L), at 5, 10 or 20 mg/kg. The animals were stimulated at the generalized seizure-triggering threshold 5 min, 2 h and then every 24 h after the drug was given, until 5 consecutive stage 5 seizures were induced. Free CuZn-SOD had little or no effect. However, SOD-L, particularly at 10 mg/kg, had a prolonged anticonvulsant effect, although there was great individual variation in the onset and duration of seizure suppression. This effect of SOD-L may be due to the ability of liposomes to act as a depot for the sustained release of drugs.  相似文献   
108.
109.
Concentrations of metabolites and immunoreactive insulin (IRI) and activities of enzymes related to energy metabolism were measured in plasma of Korean and Japanese beef cattle, which were raised by the indoor feeding system programmed to feed larger amount of roughage in their growing periods and larger amount of concentrate diet in their finishing periods (Japanese feeding system), and grazing New Zealand beef cattle. By the Japanese beef grading system, Korean and Japanese beef cattle showed high beef quality score, average grade 3.3 and 3.6, respectively. The plasma free fatty acid and lactate concentrations and lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and aspartate aminotransferase (AST) activities in Korean beef cattle were significantly higher than those in Japanese beef cattle. The plasma lactate concentration in Korean beef cattle was 8.40 mmol/l, which was similar to the values observed in lactic acidosis. The higher activities of plasma LDH, MDH and AST may indicate slight liver damage by slightly acidotic conditions in Korean beef cattle. New Zealand beef cattle fed on pasture which they harvest by grazing showed significantly lower plasma glucose, cholesterol, lactate and IRI concentrations and enzyme activities than those in Korean and Japanese beef cattle fed on larger amount of concentrate diets. Plasma metabolite concentrations and energy metabolism‐related enzyme activities may be good indicators for evaluating metabolic conditions of beef cattle raised by different feeding systems.  相似文献   
110.
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