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461.
GI Malinin 《Canadian Metallurgical Quarterly》1976,24(9):993-999
Oxidation of tissue sections by 25-30% (v/v) acetic anhydride (AA) in dimethyl sulfoxide (DMSO) resulted in facile induction of tissue carbonyls readily localized with Schiff's reagent and o-dianisidine but not with the 3-hydroxy-2-naphthoic acid hydrazide-tetraazotized diorthoanisidine method. Carbonyls generated by AA-DMSO oxidation were confined predomintly to substrates containing pyranosides. Oxidized furanosides, as represented by deoxyribonucleic acid and ribonucleic acid, gave only a residual color reaction. The AA-DMSO method possesses an advantage in that the oxidation of tissue polysaccharides does not proceed beyond the formation of carbonyly and is particularly suited for use after formol fixation. 相似文献
462.
GI Shehab 《Canadian Metallurgical Quarterly》1995,41(3):1263-1270
This research compared the compressive strength of two types of all-ceramic crown (Hi-Ceram and Duceram) as affected by selected luting cements (Zn phosphate, glass ionomer and composite resin cement). Thirty crowns of similar size and shape were constructed (15 crowns of each tested material) to fit a standard posterior tooth preparation. Five crowns from each material were cemented by one of the tested cements. The cemented crowns were loaded until catastrophic failure. A two-way analysis of variance was performed and showed that the type of utilized cement had a significant effect on the compressive strength being that Panevia Ex. resin cement the most effective one followed by glass ionomer and then finally zn phosphate cement. Statistical analysis also showed that Hi-Ceram crowns were more resistant to occlusal load than Duceram. 相似文献
463.
Universal minimization and maximization of the strain energy density, while possible in materials with cubic symmetry, is not possible for cortical long bone with its orthotropic material symmetry. Illustrating this point, it is shown that the stress state obtained when an axial load is applied along the long axis of a long bone at the midshaft is a minimizer of the strain energy density, while the stress state obtained when a load is applied perpendicular to the long axis, and perpendicular to the surface, of the mid-diaphysis of a long bone is a maximizer of the strain energy density. Thus, the bone tissue at the midshaft of a long bone is designed by nature so that it has the greatest stiffness in the direction of its long axis and its greatest impact loading resistance in the transverse direction. 相似文献
464.
AA Alvarado E Moreno-Gonzalez SR Gomez M Musella SC Loinaz AI Gonzalez-Pinto GI Garcia RC Jimenez PC Castellon S Rodriguez 《Canadian Metallurgical Quarterly》1995,66(5):711-718
Between April 1986 and August 1994, 393 orthotopic liver transplantation (OLT) have been performed at "12 de Octubre" Hospital. Among these ones we consider 274 OLT made in 223 adults and in 47 children (4 intraoperative deaths). The reconstruction of the biliary tract was performed with a choledocho-choledochostomy with T tube (CD-CD T) in 131 patients, a choledocho-choledochostomy without T tube or stent (CD-CD) in 75, a Roux-en-y-hepatico-jejunostomy (H-J) in 248, a hepatico-jejunostomy with stent (H-J St) in 13 and a choledocho-cholecisto-jejunostomy (CD-CC-J) in 3 patients. Thirthy six (13.3%) patients developed biliary complications (30 adults and 6 childrens). Fourteen (18.6%) occurred in CD-CD reconstruction and 13 (11.4%) in CD-CD T. The most common complications were leakage and stricture. Thirteen ERCP were performed in 12 patients (1 failed), all adults (CD-CD T: 3; CD-CD: 10). The main indication for ERCP was cholestasis and inability of non invasive methods ultrasound, scintigraphy and computerized tomography in determining the underlying etiology. ERCP was successful in all 12 patients: detecting strictures in 8, strictures + lithiasis in 1, stricture+lekage in 1 and leakage in 2. No complications were encountered after ERCP in our patients. ERCP is the method of choice in diagnosis of biliary complications in CD-CD biliary reconstruction. 相似文献
465.
Mycotic complications were registered in 21 out of 37 HIV-infected subjects. Oropharyngeal candidiasis was most common. It occurred prior to or concurrently with esophageal and skin candidiasis, fungemia, meningoencephalitis and disseminated lesions. With immunodeficiency progression, the prevalence and severity of mycosis go up. The causing fungi vary in great range: Candida albicans, Candida krusei. Candida tropicalis, Candida pseudotropicalis, Candida parapsilosis. Cryptococcus neoformans, Rhodotorula rubra, Penicillium chrysogenum. 相似文献
466.
S Bertelloni GI Baroncelli R Battini G Perri G Saggese 《Canadian Metallurgical Quarterly》1995,10(10):1488-1495
We studied bone mineral content (BMC), bone mineral density (BMD), cortical thickness/total width (CT/TW) ratio and cortical area/total area (CA/TA) ratio in boys with constitutional delay of puberty and the effect of short-term testosterone treatment on bone mass. Seventeen boys (age 13.1-15.8 years) who met the family history and the clinical criteria of constitutional delay of puberty were selected and enrolled in the study. All subjects were eating a diet assuring an adequate intake of calories and calcium. A subset of 8 boys (group A) was treated with testosterone depot (100 mg/month x 6 months) while 9 boys (group B) were not. At inclusion, BMC and BMD were reduced in the patients according to their chronological age (BMC -4.04 +/- 1.34 standard deviation scores [SDS]; BMD -2.95 +/- 0.56 SDS), statural age (BMC -1.75 +/- 0.79 SDS; BMD -1.69 +/- 0.78 SDS), and bone age (BMC -1.80 +/- 0.65 SDS; BMD -1.86 +/- 0.68 SDS). No significant differences between the groups were found (group A: BMC 0.480 +/- 0.57 g/cm, BMD 0.488 +/- 0.037 g/cm2, CT/TW ratio 0.43 +/- 0.4, CA/TA ratio 0.68 +/- 0.04; group B: BMC 0.476 +/- 0.060, p = NS vs. group A; BMD 0.491 +/- 0.036 g/cm2, p = NS vs. group A). At 12 months of follow-up, BMC, BMD, CT/TW ratio, and CA/TA ratio significantly increased in group A (BMC 0.70 +/- 0.13 g/cm, delta +41.1 +/- 28.8%, p < 0.003 vs. 0 month; BMD 0.617 +/- 0.082 g/cm2, delta +26.2 +/- 13.6%, p < 0.005 vs. 0 month; CT/TW ratio 0.52 +/- 0.05, delta +20.59 +/- 10.65%, p < 0.001 vs. 0 month; CA/TA ratio 0.77 +/- 0.05 vs. 0 month; CT/TW ratio 13.60 +/- 6.65%, p < 0.004 vs 0 month), but not in group B (BMC: 0.48 +/- 0.05 g/cm; delta +5.1 7.8%, p = NS vs. 00 month; BMD: 0.492 +/- 0.037 g/cm2; delta +0.54 +/- 8.7%, p = NS vs. 0 month; CT/TW ratio 0.44 +/- 0.04, delta +4.04 +/- 6.75%, p = NS vs. 0 month; CA/TA ratio 0.68 +/- 0.05, delta +2.39 +/- 5.90%, p = NS vs. 0 month). We conclude that boys with constitutional delay of puberty have reduced BMC and BMD. The delay in statural and bone ages did not totally account for the decreased bone mass. Testosterone treatment for 6 months significantly increased BMC, BMD, CT/TW ratio, and CA/TA ratio in these patients, but definitive conclusions on the efficacy of the treatment in improving adult bone mass can be drawn only when our patients reach early childhood. 相似文献
467.
468.
Perinatal events of 180 babies with nuchal cord (umbilical cord entanglement around foetal neck) over one year have been studied. The incidence of nuchal cord was 5.74% of all hospital deliveries. More than one third (39%) of them had tight nuchal cord (TNC) and 61% had loose nuchal cord (LNC). Babies with TNC were more frequently met with foetal distress (51%), prolonged second stage (11%), non-toxaemic accidental haemorrhage (7%) and operative delivery (56%) when compared to babies with LNC and controls (without nuchal cord). Nearly one fourth (24%) of the babies with TNC were born as small for date, had birth asphyxia (61%) and 8.5% died during perinatal period. Perinatal outcome was adversely affected by TNC in comparison to LNC and controls. 相似文献
469.
470.