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11.
Transurethral lithotripsy was performed in 63 patients with ureteral calculi between September 1987 and March 1991. Three types of flexible nephroureteroscopes with diameters of 12.8F, 10.5F and 9.3F were used in groups 1, 2 and 3, respectively. The rate of successful stone disintegration and the stone-free rate 3 months after lithotripsy were 73% (11 of 15 patients) and 67% (10 of 15), respectively, in group 1, 93% (26 of 28) and 82% (23 of 28), respectively, in group 2, and 95% (19 of 20) and 85% (17 of 20), respectively, in group 3. Four complications were encountered in the patients treated with the 12.8F device (group 1). Our results clearly show that use of a slimmer fiberscope and the effect of learning to perform techniques with the flexible nephroureteroscope improved the success rate and decreased the complication rate in transurethral lithotripsy.  相似文献   
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MRI and SPECT findings in amyotrophic lateral sclerosis   总被引:1,自引:0,他引:1  
Summary MRI was performed in 21 patients and single photon emission computed tomography (SPECT) withN-isopropyl-p-123I iodoamphetamine in 16 patients, to visualize upper motor neurone lesions in amyotrophic lateral sclerosis. T2-weighted MRI revealed high signal along the course of the pyramidal tract in the internal capsule and cerebral peduncle in 4 of 21 patients. SPECT images were normal in 4 patients, but uptake was reduced in the cerebral cortex that includes the motor area in 11.  相似文献   
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Age-related changes of reduced nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d)-containing neurons were examined quantitatively in the laterodorsal tegmental nucleus (TLD) and the caudate-putamen of mice. Six 2-month-old and six 25- to 30-month-old DDD mice were studied using computer-assisted image analysis. Although no age-related changes in neuronal counts were found in the TLD, the cell size in this nucleus showed a statistically significant reduction with aging. In addition, the degree of the age-related neuronal shrinkage differed within the TLD; the most significant occurring in the rostral, less in the caudal third and no significant alteration being found in the middle third portion of TLD. In contrast, NADPH-d-positive neurons in the striatum did not show distinct age-related changes. NADPH-d-containing neurons in the TLD correspond to cholinergic cells, which project to the forebrain. Thus, the age-related shrinkage of NADPH-d neurons in the TLD may be related to the cholinergic dysfunctions seen in the forebrain of senescent mice.  相似文献   
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Yasuda K  Inoue S  Tabata Y 《Tissue engineering》2004,10(9-10):1587-1596
The initial attachment, proliferation, and osteogenic differentiation of stromal cells from human fat tissue were investigated in three-dimensional nonwoven fabrics prepared from polyethylene terephthalate (PET) fiber with different diameters. The largest number of cells initially attached was observed in the nonwoven fabrics prepared from PET fiber with a diameter of 22.0 microm, irrespective of fabric porosity. The number of cells attached was larger and the cells were distributed more homogeneously in the fabrics by the agitated seeding method than by the static seeding method. The culture method depended on the time profile of cell proliferation. Cell proliferation improved in the following order: stirred (spinner flask) culture method > agitated culture method > static culture method. In addition, cells proliferated homogeneously in fabrics by the stirred culture method. When evaluated as a measurement of cell osteogenic differentiation, the activity of alkaline phosphatase (ALP) was not influenced by the diameter of fabrics. The static culture method tended to enable cells to enhance ALP activity, in contrast with the stirred and agitated culture methods. It is concluded that fabric fiber diameter and culture method greatly affected the proliferation and differentiation of cells in nonwoven fabrics.  相似文献   
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Neovascularization of the dissociated central nervous tissue transplanted into the lateral ventricle of the rat was studied using laminin immunohistochemistry. A very high immunoreactive response to laminin was demonstrated in the presumably newly formed vessels within the transplants and the graft-host borders. The growing tips and fine spike-like sprouts called 'streamers' were also highly stained with laminin immunoreactivity. In contrast, laminin immunoreactivity was negligible in the vessels in the host brain. Therefore, these results indicate that laminin may be utilized as a marker for the newly formed vessels in neural transplantations.  相似文献   
17.
Metabolism of amyloid-beta peptide (Abeta) is closely associated with the pathology and etiology of Alzheimer's disease (AD). Since neprilysin is the only rate-limiting catabolic peptidase proven by reverse genetics to participate in Abeta metabolism in vivo, we performed detailed immunohistochemical analysis of neprilysin in mouse brain using neprilysin-deficient mice as a negative control. The aim was to assess, at both the cellular and subcellular levels, where Abeta undergoes neprilysin-dependent degradation in the brain and how neprilysin localization relates to Abeta pathology in amyloid precursor protein (APP)-transgenic mice. In hippocampus, neprilysin was present in the stratum pyramidale and stratum lacunosum-moleculare of the CA1-3 fields and the molecular layer of the dentate gyrus. Confocal double immunofluorescence analyses revealed the subcellular localization of neprilysin along axons and at synapses. This observation suggests that after synthesis in the soma, neprilysin, a type II membrane-associated protein, is axonally transported to the terminals, where Abeta degradation is likely to take place. Among various cell types, GABAergic and metabotropic glutamate 2/3 receptor-positive neurons but not catecholaminergic or cholinergic neurons, expressed neprilysin in hippocampus and neocortex, implying the presence of a cell type-specific mechanism that regulates neprilysin gene expression. As expected, Abeta deposition correlated inversely with neprilysin expression in TgCRND8 APP-transgenic mice. These observations not only support the notion that neprilysin functions as a major Abeta-degrading enzyme in the brain but also suggest that down-regulation of neprilysin activity, which may be caused by aging, is likely to elevate local concentrations of Abeta at and around neuronal synapses.  相似文献   
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OBJECTIVE: We investigated the usefulness of skin prick test (SPT) for the diagnosis of egg white (EW) allergy in infants with atopic dermatitis who showed negative to EW CAPRAST, and followed up the EW-CAPRAST in this study. SUBJECTS AND METHODS: Data of negative SPT using Bifurcated needle (BN) were analyzed from the data of 202 atopic dermatitis infants, who had received SPT from January in 2001 to April in 2005. From the negative SPT value (average and standard deviation) positive SPT value was obtained. Among 202 cases, 89 suspected-egg allergy infants with negative IgE CAPRAST against EW at the time of first visit were recruited to examine the usefulness of SPT. Positive conversion of EW-CAPRAST was checked in 78 cases (65: egg allergy+, 13: egg allergy(-)) who had been followed up in our outpatient clinic. RESULTS: Range of negative SPT control value (mean+2SD) using BF among infants could be set as less than 2 mm for wheal and/or 5 mm for erythema. Among 89 suspected-egg allergy infants with negative EW-CAPRAST, 72 infants (80.9%) were diagnosed as egg allergy by the combination of elimination and provocation test, interestingly 39 infants (54.2%) showed positive SPT results. In the follow up study of 78 negative EW-CAPRAST cases, 47 EW-CAPRAST out of 65 egg-allergy cases turned positive later infantile period (mean EW-CAPRAST: 9.6+/-16.7 Ua/ml at 9.9+/-5.6 months old). EW-CAPRAST of 7 cases in 13 non-egg allergies also turned positive in the follow up, however EW-CAPRAST titer was relatively lower compared to that of egg allergies (1.1+/-1.5 Ua/ml at 13.3+/-2.6 months old). CONCLUSIONS: We experienced fairly number of atopic infants with negative EW-CAPRAST at the first outpatient visit, who were later diagnosed as egg allergy. In about half of these cases, SPT egg-allergy infants, three quarter of EW-CAPRAST turned positive around 10 months old. EW-CAPRAST of atopic infants without egg allergy also turned transiently and slightly positive. In the conclusions, SPT seemed to be more useful than EW-CAPRAST for the diagnosis of egg allergy in early infantile period, however provocation test should be required for the definitive diagnosis in suspected-egg allergy infants without any proof of egg-sensitization.  相似文献   
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BACKGROUND: Manual puncture of the trophectoderm of human blastocysts with a needle before vitrification increases their survival rate, but the embryos take a long time to re-expand. This study examined whether causing human blastocysts to collapse by manual pipetting before vitrification would allow more rapid re-expansion and improve pregnancy rates. METHODS: After embryo transfer in IVF cycles, surplus embryos that developed to the expanded blastocyst stage were placed in cryoprotectant and then artificially shrunk by mechanical pipetting with a fine hand-drawn glass pipette slightly smaller in diameter than the blastocyst. The shrunken embryos were placed in a small volume of vitrification solution and plunged into liquid nitrogen on a cryotop. The blastocysts were thawed by warming and then dilution in 1 mol/l sucrose. RESULTS: Of 49 expanded vitrified blastocysts, 48 (98%) re-expanded within 3 h after warming. Following transfer (48 blastocysts in 28 cycles), 14 women (50%) became clinically pregnant, and the implantation rate was 33% (16/48). Eight healthy babies have been born in six deliveries, and the other eight pregnancies are ongoing. To date, there have been no spontaneous abortions. CONCLUSIONS: The results suggest that artificial shrinkage with pipetting is a simple and effective technique to assist successful cryopreservation of expanded blastocysts by vitrification.  相似文献   
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