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A juvenile animal model has been developed to study the growth potential of ileum in the urinary tract. Patch ileocystoplasties of known surface area were constructed in dogs of Group 1. Nonrefluxing ileal nipple valves of known length were created to replace one ureter in dogs of Group 2. After the juvenile animals grew and at minimum doubled their weight, they were reoperated and augmentation surface areas were remeasured at various physiologic intravesical pressures. Nipple valve lengths were remeasured after cystograms ruled out reflux. Results show that the bowel augmentation and an identical control segment increased in surface area proportionate to animal growth and that hydrostatic dilation caused further surface area increase. Nipple valves did not grow and in fact shortened, but remained nonrefluxing. The conclusion is that in the pediatric population, consideration should be given to downscaling the size of bladder augmentations or diversions in anticipation of future bowel growth, but that one should not shorten the ileal nipple valves. 相似文献
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Initial 31P spectroscopy results from a 4-T whole-body system are reported. Localized spectra from the human head, liver, and calf were obtained using DRESS, slice-interleaved DRESS, and volume 3DFT spectroscopic imaging techniques. Substantial reductions in data acquisition times to 10 s-4 min were achieved relative to previous similar experiments at 1.5 T. Some gain in spectral resolution (as measured in ppm) was also realized in the head. 相似文献
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The effects of Bay K 8644 and of nifedipine on histamine-induced mechanical and electrical responses were studied in the longitudinal smooth muscle of the ileum and in the taenia coli isolated from the guinea-pig. Nifedipine (10(-9)-10(-7) M) depressed the tonic and phasic components of histamine contraction. Phasic tension was less sensitive to nifedipine inhibition than was tonic tension (I50: 27 +/- 6 and 2.6 +/- 0.4 nM respectively). Bay K 8644 (10(-8)-10(-7) M) increased tension and rhythmic activity of intestinal smooth muscle and potentiated the histamine responses. The phasic tension evoked by histamine 10(-5) M and the phasic tension evoked by the KCl depolarizing solution showed the same sensitivity to nifedipine inhibition (I50: 28 +/- 5 nM) and were similarly potentiated by Bay K 8644. The tonic tension in response to the KCl-depolarizing solution was more sensitive to nifedipine inhibition than was the tonic tension in response to histamine and was not potentiated by Bay K 8644. These results indicate that different Ca entry pathways, dependent or not on modification of the membrane potential, are involved in the contractile response evoked by histamine in intestinal smooth muscle. 相似文献
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Extradural sacral (caudal) block was performed in 17 cases (14 patients) of chronic low back pain. In each case 22 ml of a bupivacaine/methylprednisolone solution incorporating a radioopaque dye was injected over a 2-min period. Patients were randomly assigned to receive the injection in the horizontal position or with 15 degrees head-up or head-down tilt applied to the operating table. Results indicate that analgesia is usually more localised than spread of solution determined by x-ray evidence and that higher levels of analgesia are achieved in patients in the head-up position. Possible causes are the differing distribution characteristics of the constituents of the solution and the gravitational effects of posture on cerebrospinal fluid mechanics. Technical problems associated with obesity, congenital abnormalities, vascular uptake of solution, and delayed spread of the injectant due to adhesions are discussed. 相似文献
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Demetrius M Maraganore Matthew J Farrer Timothy G Lesnick Mariza de Andrade James H Bower Dena Hernandez John A Hardy Walter A Rocca 《Movement disorders》2003,18(11):1233-1239
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene. 相似文献
19.
Narrowband irradiation of water protons with a surface coil yields significant nuclear Overhauser enhancement (nOe) of phosphocreatine (PCr) and some adenosine triphosphate (ATP) moieties in localized and unlocalized phosphorus (31P) NMR spectra from chest and heart muscle. In seven normal subjects at 1.5 T the nOe values were 0.6 +/- 0.3, 0.6 +/- 0.3, 0 +/- 0.3, and 0.3 +/- 0.2 for myocardial PCr, gamma-ATP, alpha-ATP, and beta-ATP, respectively, not significantly different from those in chest muscle. Distortion of the measured PCr/ATP ratios due to differences in the nOe may require accurate correction to realize the full benefit of the effect in studies involving quantitative intergroup comparisons. 相似文献
20.
M Robaszkiewicz E Hardy A Volant J B Nousbaum J M Cauvin G Calament F X Robert J P Saleun H Gouerou 《Gastroentérologie clinique et biologique》1991,15(10):703-710
Dysplasia is the only marker for malignant potential in Barrett's esophagus. The histologic interpretation of dysplasia is sometimes difficult, particularly when attempting to distinguish dysplastic changes from those of a regenerating and inflammatory mucosa. In order to find an objective marker to identify patients with high risk of malignant transformation, the authors evaluated 497 biopsies from 66 patients with Barrett's esophagus with flow cytometry. The aim of the study was to correlate DNA content and proliferative abnormalities with histology. All biopsies classified histologically as negative for dysplasia had a diploid DNA content. The percentage of biopsies with an aneuploid DNA content increased with the histologic grade of dysplasia: 2 percent of indefinite dysplasia, 11 percent of low grade dysplasia, 44 percent of high grade dysplasia and 78 percent of biopsy specimens with cancer biopsies were aneuploid. Mean S and G2M fractions of diploid biopsy specimens increased with the severity of histologic changes. The S and G2M fraction threshold values that could differentiate patients that were negative for dysplasia from those with high grade dysplasia or cancer were 9 percent and 6 percent, respectively. Aneuploidy or G2M fraction greater than 6 percent was the best discriminating criteria between those two distinct groups of patients. All 6 patients with high grade dysplasia or cancer had aneuploid cell populations or increased G2M fraction, whereas none of the 35 patients whose biopsies were histologically negative for dysplasia had evidence of genomic instability or increased G2M fraction. Flow cytometric abnormalities were found in 10 out of 25 patients whose biopsies were classified as indefinite for dysplasia or low grade dysplasia.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献