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81.
82.
AM Elbahnasy AL Shalhav DM Hoenig OM Elashry DS Smith EM McDougall RV Clayman 《Canadian Metallurgical Quarterly》1998,159(3):676-682
PURPOSE: We determine whether there is a significant relationship between the spatial anatomy of the lower pole, as seen on preoperative excretory urography (IVP), and the outcome after shock wave lithotripsy or ureteroscopy for a solitary lower pole caliceal stone 15 mm. or less. MATERIALS AND METHODS: Between January 1992 and June 1996, 34 patients with 15 mm. or less solitary lower pole stone underwent ureteroscopy with intracorporeal lithotripsy (13) or extracorporeal shock wave lithotripsy (ESWL) with a Dornier HM3 lithotriptor (21). On pretreatment IVP lower pole infundibular length and width, infundibulopelvic angle of the stone bearing calix were measured. Stone size and area were determined from an abdominal plain x-ray. A plain x-ray of the kidneys, ureters and bladder was obtained in all patients at a median followup of 12.3 and 8 months in the ureteroscopy and ESWL groups, respectively. RESULTS: After initial therapy the overall stone-free rate was 62 and 52% in the ureteroscopy and ESWL groups, respectively. Stone-free status after ESWL was significantly related to each anatomical measurement. Infundibulopelvic angle 90 degrees or greater, and infundibular length less than 3 cm. and width greater than 5 mm. were each noted to correlate with an improved stone-free rate after ESWL. In contrast, the stone-free rate after ureteroscopy was not statistically significantly impacted by these anatomical features, although a clinical stone-free trend was identified relating to a favorable infundibular length and infundibulopelvic angle. The infundibulopelvic angle was 90 degrees or greater in 4 stone-free patients (12% overall), including 2 who underwent ureteroscopy and 2 who underwent ESWL. On the other hand, in 2 and 4 stone-free patients (18% overall) who underwent ureteroscopy and ESWL, respectively, favorable radiographic features consisted of a short, wide but acutely angulated infundibulum with the infundibulopelvic angle less than 90 degrees, and infundibular length less than 3 cm. and width 5 mm. or greater. In contrast, in 4 and 6 patients (29% overall) who underwent ureteroscopy and ESWL, respectively, all 3 radiographic features were unfavorable with the infundibulopelvic angle less than 90 degrees, and infundibular length greater than 3 cm. and width less than 5 mm. In these cases the stone-free rate was 50 and 17% after ureteroscopy and ESWL, respectively. CONCLUSIONS: The 3 major radiographic features of the lower pole calix (infundibulopelvic angle, and infundibular length and width) can be easily measured on standard IVP using a ruler and protractor. Each factor individually has a statistically significant influence on stone clearance after ESWL. A wide infundibulopelvic angle or short infundibular length and broad infundibular width regardless of infundibulopelvic angle are significant favorable factors for stone clearance following ESWL. Conversely, these factors have a cumulatively negative effect on the stone clearance rate after ESWL when they are all unfavorable. In ureteroscopy spatial anatomy has less of a role in regard to stone clearance but it may have a negative impact when there is uniformly unfavorable anatomy. 相似文献
83.
NT Telang F Arcuri OM Granata HL Bradlow MP Osborne L Castagnetta 《Canadian Metallurgical Quarterly》1998,77(10):1549-1554
Targeted overexpression of the c-myc oncogene induces neoplastic transformation in immortalized, non-tumorigenic mouse mammary epithelial cells (MMEC). Experiments in the present study were conducted to examine whether cellular transformation induced by c-myc oncogene is associated with altered metabolism of 17beta-oestradiol (E2). The parental, MMEC and the stable c-myc transfectant (MMEC/myc3) cell lines were compared for major oestrogen metabolic pathways, namely E2 and E1 interconversion, and C2- and C16alpha-hydroxylation by both high-pressure liquid chromatography (HPLC) analysis and the 3H release assay using specifically labelled [C2-3H]E2 or [C16alpha-3H]E2. The reductive conversion of E1 to E2 was about 14-fold and 12-fold higher than the oxidative conversion of E2 to E1 in MMEC and MMEC/myc3 cells respectively. However, in MMEC/myc3 cells, both reductive and oxidative reactions were decreased by about 32% and 12% relative to those seen in the parental MMEC cells (P = 0.0028). The extent of C16alpha-hydroxylation was increased by 164.3% (P < 0.001), with a concomitant 48.4% decrease (P < 0.001) in C2-hydroxylation in MMEC/myc3 cells; this resulted in a fourfold increase in the C16alpha/C2 hydroxylation ratio in this cell line. Thus, a persistent c-myc expression, leading to aberrant hyperproliferation in vitro and tumorigenesis in vivo, is associated with an altered oestrogen metabolism. However, it remains unclear whether this represents a result of oncogene expression/activation or is rather a consequence of phenotypic transformation of the cells. 相似文献
84.
85.
The erythroleukaemic cell line TF-1, infected with either the pBabe neo retrovirus or the retrovirus bearing the human erythropoietin (hEpo) gene, developed three growth factor-independent clones. Erythropoietin (Epo), interleukin-3 (IL-3) and granulocyte-macrophage colony stimulating factor (GM-CSF) accelerated the proliferation of these clones. Autonomous growth of the clones was independent of Epo because it was not altered by Epo anti-sense oligonucleotides, nor was Epo detectable in culture supernatants. Cells from the mutant clones could not be induced by Epo to express glycophorin A and haemoglobin synthesis was markedly reduced. Haemin reversed the block in Epo-induced haemoglobin synthesis. Acquisition of growth factor-independence appears to be linked with the selective loss of differentiation capacity. These cells may provide a useful model for the study of the mechanisms involved in leukaemic transformation. 相似文献
86.
R Lisker MA López S Jasqui S Ponce De León Rosales R Correa-Rotter S Sánchez OM Mutchinick 《Canadian Metallurgical Quarterly》2003,75(3):399-403
It has been reported that Vitamin D receptor polymorphisms are associated with osteoporosis, particularly those demonstrated by the BsmI and FokI restriction enzymes. Herein we report the results of a case-control study performed in postmenopausal Mexican women. We studied 65 osteoporotic women (< or = -2.5 SD bone mineral density [BMD] of young normal females) and 57 controls (over 90% > or = -1.5 SD BMD of young normal females. Restriction enzymes BsmI and FokI were used to identify polymorphisms. Odds ratios and their 95% confidence intervals were calculated, and analysis was performed controlling for age as a covariate. The BsmI genotypes revealed a higher frequency of the bb genotype in cases than in controls, contradicting much of the literature that suggests this genotype protects females against osteoporosis. Regarding the FokI genotypes, we were unable to confirm that the FF genotype has a protective effect against osteoporosis. The inconsistencies found in the literature and the results obtained in the present work suggest to us that other genetic and nongenetic factors are involved in the occurrence of osteoporosis, confounding the results of the possible association of osteoporosis and VDR polymorphisms. 相似文献
87.
A Gupta S Chandrasekhar R Pal GP Talwar OM Singh 《Canadian Metallurgical Quarterly》1998,17(7):573-581
We identified a 685-nucleotide gene fragment that codes for the transmembrane and cytoplasmic domains of glycoprotein of the LEP strain rabies virus and carried out experiments designed to express a novel fusion protein on the cell surface. The cDNA encoding the membrane anchor sequence was fused in the correct reading frame to the 3' end of the cDNA encoding the beta subunit of human chorionic gonadotropin (beta(h)CG), a secretory glycoprotein that is used as an antigen for a contraceptive vaccine being developed in our laboratory. The fusion gene cassette was placed under the control of a vaccinia virus early promoter and cloned in a host-restricted fowlpox viral vector. The recombinants, when used to infect mammalian cells that do not allow the replication of fowlpox virus, expressed the N-terminal 135 amino acid residues of beta(h)CG anchored in the cell membrane by the 75-amino acid C-terminal sequence derived from rabies virus glycoprotein. This hybrid protein is correctly processed post-translationally and transported efficiently to the plasma membrane of non-permissive cells such that the anchored beta(h)CG molecule retains the correctly folded native antigenic epitope(s). 相似文献
88.
89.
Ion-sensitive endogenous regulators of Na+,K+-ATPase obtained from epithelium of rat small intestine
From epithelial layer of rat intestinal were selected water soluble substances which influenced on Na+,K(+)-ATPase activity in 2 different ways: substances with molecular weight 220 Da, 400 Da were its activators, substance with weight 150 Da-inhibitor. Na+,K(+)-ATPase activators preincubated previously with Na+ acquire properties of inhibitors. Bivalent cations Ca, Mg remove this effect of Na-ions. 相似文献
90.
HD Petersen M Larsen M Mannstaedt GL Skytt OM Vedel JH Wandall 《Canadian Metallurgical Quarterly》1998,160(29):4302-4306
Physicians for Human Rights/Denmark visited Kashmir three times in 1993 and 1994. In Indian-held Kashmir we examined victims of torture and gunshots and we assessed similar evidence collected by local lawyers and doctors. In refugee camps for Indian Kashmiries we examined ten children, who were reported to have been tortured at the age of 5-14 years, and ten other children who allegedly had been ill-treated. Furthermore, 17 adults, who reported that they had been tortured, were examined. In nearly all cases there were physical findings in accordance with the histories of torture. In many cases, including those of the children, the findings were highly remarkable by their shape and localization. We interpret them as evidence of intentionally inflicted injuries. In the refugee camps we carried out a prevalence study of exposure to organized violence. Approximately 95% of all families had been exposed to violence; 35% reported that their children had been ill-treated. The physical findings indicate that intentional traumatization of civilians including children in Indian-held Kashmir takes place; the results of the prevalence study suggest that exposure to violence is widespread. 相似文献