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1.
Three hundred and sixty one extracorporeal lithotripsies for renal, ureteric and bladder stones have been performed by means of a system of ultrasonographic detection and piezoelectric destruction (EDAP LT01). The localisation of the stone is achieved by a 5 MHz real time sectorial transducer situated in the centre of a small dish containing 320 piezoelectric elements concentrated in a source 5 mm wide by 15 mm high. The pressure recorded in vitro is 900 bars. The stone is easily detected in 87.2% of cases, difficult to detect in 10% of cases and impossible to detect in 28% of cases. By using a frequency of 1.25 to 5 per second, extracorporeal lithotripsy can be performed without any local, regional or general anaesthesia and without premedication in the 120 patients with a renal stone, reviewed between 1 and 3 months, 88 (73%) were considered to be complete successes. Ten (8%) were considered to be failures and 19 (21%) were considered to be partial successes. The best results were obtained in stones of the renal pelvis less than 20 mm in diameter. These results relate to a mean series which must take into account the successive improvements made to the lithotripter. Today, stone fragmentation is obtained in 93% of cases. Thirty six stones of the lumber and pelvic ureter were treated with success rates of 93% and 50%, respectively. Six bladder calculi were treated with a 50% success rate. Forty two patients were treated without being admitted to hospital.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Lp(a) lipoprotein in cerebrovascular disease and dementia   总被引:1,自引:0,他引:1  
Lp(a) lipoprotein has been considered an independent risk factor in the development of coronary heart disease (CHD). We examined the role of Lp(a) in patients with cerebrovascular disease (CVD) and those with dementia. The Lp(a) concentration in patients with CHD, those with cerebral infarction due to a large artery occlusion and those with vascular dementia (VD) was significantly higher than that of age-matched control subjects. However, the Lp(a) concentration was not high in cerebral infarction due to a small artery occlusion, intracerebral hemorrhage and dementia of the Alzheimer type (DAT). The present results suggest that Lp(a) should cause VD as well as CVD, and that Lp(a) should be one of the indicators that distinguish VD from DAT.  相似文献   
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Jack pine (Pinus banksiana Lamb.) retain their seeds from year to year, so that in an irradiated forest, each tree receives a specific dose rate but has seeds that have accumulated a range of total doses. The Field Irradiator-Gamma facility in Pinawa, Manitoba, contains jack pine that have been irradiated longer and at lower dose rates than previously reported. Seed germination and germination rate were examined on seeds irradiated on the parent tree for up to 5 years. Germination rate was most sensitive and showed deleterious effects at 1.1 mGy hr-1. This is not much lower than results reported by others in shorter-term studies. Effects were related to dose rate rather than total dose. Hormesis, indicated by statistically significant increased germination rate, was evident at 0.6 mGy hr-1. To put these results into context, the concentrations of selected radionuclides that, through internal contamination, would deliver 1.1 mGy hr-1 to plants were estimated. For 99Tc and 129I, these concentrations are far above the chemical toxicity thresholds for plants. Clearly, as assessments of waste repositories begin to consider effects on organisms other than humans, such as plants, chemical toxicity will be an important feature.  相似文献   
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The preoptic area contains most of the luteinizing hormone releasing hormone immunoreactive neurons and numerous monoaminergic afferents whose cell origins are unknown in sheep. Using tract tracing methods with a specific retrograde fluorescent tracer, fluorogold, we examined the cells of origin of afferents to the medial preoptic area in sheep. Among the retrogradely labeled neurons, immunohistochemistry for tyrosine hydroxylase, dopamine-β-hydroxylase, phenylethanolamine N-methyltransferase, and serotonin was used to characterize catecholamine and serotonin fluorogold labeled neurons. Most of the afferents came from the ipsilateral side to the injection site. It was observed that the medial preoptic area received major inputs from the diagonal band of Broca, the lateral septum, the thalamic paraventricular nucleus, the lateral hypothalamus, the area dorsolateral to the third ventricle, the perimamillary area, the amygdala, and the ventral part of the hippocampus. Other numerous, scattered, retrogradely labeled neurons were observed in the ventral part of the preoptic area, the vascular organ of the lamina terminalis, the ventromedial part of the hypothalamus, the periventricular area, the area lateral to the interpeduncular nucleus, and the dorsal vagal complex. Noradrenergic afferents came from the complex of the locus coeruleus (A6/A7 groups) and from the ventro-lateral medulla (group A1). However, dopaminergic and adrenergic neuronal groups retrogradely labeled with fluorogold were not observed. Serotoninergic fluorogold labeled neurons belonged to the medial raphe nucleus (B8, B5) and to the serotoninergic group situated lateral to the interpeduncular nucleus (S4). In the light of these anatomical data we hypothesize that these afferents have a role in the regulation of several functions of the preoptic area, particularly those related to reproduction. Accordingly these afferents could be involved in the control of luteinizing hormone releasing hormone (LHRH) pulsatility or of preovulatory LHRH surge.  相似文献   
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Cytochrome P450 IID6 is an autoantigen recognized by the sera of children affected with a subtype of autoimmune hepatitis. It was hypothesized that a mutation in the CYP2D6 gene could explain the autoimmune response in these patients. To examine this question, genomic DNA from peripheral lymphocytes (n = 9) and liver (n = 1) of 10 patients with anti-LKM-1 antibody was analysed by Southern blot for genetic association studies between a particular CYP2D6 haplotype and autoimmune hepatitis. In addition, a region of CYP2D6, from the same genomic DNA, was amplified by polymerase chain reaction (PCR) and digested by BstNI, in a search for the most prevalent 29B mutation, described in subjects who do not express the P450 IID6. Total RNA and proteins, prepared from the liver of an anti-LKM-1+ patient, were analysed by Northern and Western (immunoblot) blots respectively. Our results do not reveal any major structural change in the DNA of this patient at the CYP2D6 locus that could explain their autoimmune response. Corroborating this observation, no changes were noted either in P450 IID6 mRNA size or in the corresponding protein. However, these data do not exclude the possibility of subtle changes in the protein due to point mutations in critical regions that might trigger an autoimmune response.  相似文献   
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Complex reciprocal interactions between hepatitis C (HCV) and hepatitis B (HBV) viruses (HBV) have been reported. We examined the influence of HBV on HCV RNA titers in 376 HCV/HIV-coinfected patients (30 were also HBsAg positive). Regression analyses identified negative HBsAg and male sex as factors associated with HCV RNA values >500,000 IU/mL.  相似文献   
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