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101.
LS Palmer GJ Andros M Maizels WE Kaplan CF Firlit 《Canadian Metallurgical Quarterly》1997,49(4):604-608
OBJECTIVES: To evaluate the management approach for vesicoureteral reflux (reflux) into a solitary kidney. METHODS: Outcomes of all children with solitary kidneys and reflux managed between 1981 and 1996 were reviewed. Solitary kidneys were documented by nuclear renography and ultrasonography; reflux was graded after cystography. Management consisted of observation and antimicrobial prophylaxis or surgery by ureteroneocystostomy or subureteric injection of polytetrafluoroethylene (STING). Follow-up ranged from 3 months to 14 years and included serial cystography, sonography, and serum creatinine measurement. RESULTS: Twenty-one patients with a median follow-up of 26 months were identified. Etiologies included contralateral renal agenesis (14 children), multicystic dysplastic kidney (5 children), or nonfunctioning ureteropelvic junction obstruction (2 children). Low-grade (I to II) reflux was identified in 6 children, and high grade (III to V) was identified in 15. Reflux resolved in 20 patients. Five children with low-grade reflux were managed without surgery and demonstrated reflux resolution after a mean of 20.5 months. Renal function deteriorated in only 1 child. Ureteroneocystostomy was performed in 13 children with grades III to V reflux, and STING was performed in 1 child with grade II reflux. Every surgical patient maintained stable renal function and was infection-free during a mean follow-up of 56 months. Management by observation in 2 children with grades IV to V reflux resulted in spontaneous resolution in one and stable grade IV in the other. CONCLUSIONS: Reflux into the solitary functioning kidney may be managed by the same strategies used to manage unilateral reflux in children with two normally functioning kidneys: low-grade reflux by observation/ chemoprophylaxis until spontaneous resolution occurs, and higher grades by surgery to protect renal function; however, chemoprophylaxis and serial imaging may be used until well-defined indications for surgery are satisfied. Renal function should be monitored diligently. 相似文献
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We have analyzed nucleotide sequence variation at the Glucose dehydrogenase (Gld) locus from four populations of Drosophila melanogaster from four continents. All four population samples show a significant reduction in silent variation compared to the neutral expectation. The levels of silent variation across all four populations are consistent with the predictions of the background selection model; however, Zimbabwe has a remarkably low level of variation. In the face of dramatically reduced silent polymorphism, an amino acid variant, leading to the common allozyme polymorphism at Gld, remains in low to intermediate frequency in all non-African samples. In the Chinese population sample, the ratio of replacement to silent variation is significantly elevated compared to the neutral expectation. The difference in patterns of variation across these population samples suggests that selection on Gld (or the Gld region) has been different in the Chinese population than in the other three. 相似文献
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Recent work in many laboratories has revealed that cytokines are important mediators of inflammation, host defense, and tissue injury in a variety of neurological diseases. A role for astrocytes and microglia in these diseases has been considered pivotal, since both cell types readily produce and respond to cytokines in vitro and show morphologic and immunocytochemical evidence for activation in vivo. Although much of the work documenting these events has been generated in rodent systems, our laboratory has focused on human cell culture systems to define the nature of the activating signals for human microglia and astrocytes and their responses to activating cytokines and growth factors and evidence for activation. The results have shown that interleukin-1 (IL-1) is a potent activator of human astrocytes and induces cytokines such as tumor necrosis factor alpha and interleukin-6, and is a potent activator of nitric oxide generation in astrocytes. Astrocytes also promote microglial growth and differentiation through production of colony-stimulating factors, an activity that is enhanced following activation with IL-1. This review will summarize the human glia data generated in this and other laboratories and present hypotheses how glia may participate in certain human central nervous system diseases. 相似文献
107.
Red blood cells are still transfused inappropriately in spite of recent media attention and public awareness about the risks of blood products. A prospective audit was conducted to determine the avoidable blood transfusion rates in the elective perioperative setting utilising the guidelines issued by the American College of Physicians (ACP). Of 82 consecutive adult patients who were admitted for major elective surgery over a 3-month period, 28 were transfused a total of 94 units of homologous SAG-M blood, of which 50 (53%) were inappropriate as recommended by the ACP guidelines. Violations of the guidelines were perioperative transfusion in bleeding patients who were haemodynamically stable (31%) and transfusion in asymptomatic, stable patients solely to attain a haemoglobin level above 10 g% (22%). There is a need for objective, easily adaptable and widely disseminated consensus guidelines to the indications for red blood cell transfusion. 相似文献
108.
The zeta protein kinase C isoform (PKC-zeta) was purified from the testis of the grey mullet Mugil cephalus and has relative masses (M(r)) of 65,000 and 63,000. The subunits of PKC-zeta from spermatozoa degenerated to M(r) 58,000 and 53,000 after continuous freezing and thawing. Proteins of M(r) 48,000 on the oolemma of the grey mullet Mugil cephalus were found to be the reaction proteins of the PKC-zeta from spermatozoa. 相似文献
109.
SJ Schwarz JR Claus H Wang NG Marriott PP Graham CF Fernandes 《Canadian Metallurgical Quarterly》1997,76(10):1450-1456
The pink color defect in cooked, uncured turkey is a sporadic problem that can result in economic loss and consumer dissatisfaction. Fourteen ligands were tested in ground turkey samples for their ability to reduce pink color development in control samples and in the presence of 150 ppm sodium nitrite or 1.0% nicotinamide (pink color producing agents). The 14 ligands evaluated were: 3-amino pyridine (AP), 4-benzoylpyridine (BP), diethylenetriamine pentaacetic acid (DA), ethylenedinitrilo-tetraacetic acid disodium salt (EA), 2,3 dihydroxybenzoic acid (DB), 3-ethyl pyridine (EP), trans 1,2-diaminocyclohexane-N,N,N',N' tetraacetic acid monohydrate (HA), calcium reduced nonfat dried milk (NM), 2,3 phthalic acid (PA), 3-picoline (PC), pyrrole (PY), pyridazine (PZ), pyridinedicarboxcylic acid (YA), and pyrazinedicarboxcylic acid (ZA). All ligands were incorporated into ground turkey at 0.20 mg/g (meat weight basis) except for NM (30 mg/g). Color was evaluated using a reflectance spectrophotometer to measure pigment changes (nicotinamide hemochrome, nitrosohemochrome) and with a chroma meter to determine CIE L* a* b* values. Reduction in pink color development was apparent with the addition of the ligand alone and in the presence of sodium nitrite and especially nicotinamide. The four most effective ligands tested were DA, EA, HA, and NM. In general, pink color reduction was highest in the ligand only and the ligand plus nicotinamide samples as was observed by CIE a* and nicotinamide hemochrome value reductions. 相似文献
110.