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31.
Many patients over the age of 55 with end stage renal disease in the United Kingdom are denied dialysis or transplantation. Although the reasons are complex, anticipation of a poor prognosis for these patients might explain why most British renal units impose an arbitrary age limit on the acceptance of patients for treatment. A study was therefore conducted to examine the prognosis and quality of life of 84 patients (mean age 59.6 years, range 55-72) accepted into our renal replacement programme from the beginning of 1975. The five year survival of the patients was 62.0% with 78.1% of the survivors either having successful transplants or caring for themselves using home haemodialysis or continuous ambulatory peritoneal dialysis. The results show that in terms of survival, economics, and rehabilitation it is both feasible and reasonable to treat middle aged and elderly patients with end stage renal disease. These patients should therefore not be denied dialysis or transplantation on the basis of age alone, and the lack of resources and other factors that allow this state to persist in Britain should be rapidly redressed.  相似文献   
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The C-D stretching regions of the infrared and Raman spectra of 14 different palmitic and stearic acids containing isolated CD2 groups are reported. Anomalous behaviour is observed when substitution occurs near the terminal methyl group, which behaviour can not be explained in terms of crystal field effects.  相似文献   
33.
The kidneys of nine fetuses whose mothers were chronically hypertensive were examined microscopically. Three of these mothers used antihypertensive agents throughout pregnancy including one who used an angiotensin-converting enzyme (ACE) inhibitor. The tubular defects found in these kidneys were compared to the kidneys of 20 normal controls, 13 fetuses with various multiple malformation syndromes and six cases of the twin to twin transfusion syndrome. Evidence from these cases as well as the literature suggest that the primary mechanism by which ACE inhibitors affect development of the fetal kidney is through decreased renal blood flow.  相似文献   
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Summary Four mutant strains of the nematodeCaenorhabditis elegans previously isolated as defective in thermotaxis (Hedgecock and Russell, 1975) were compared to the wild type in tests of their thermal range of activity and chemotaxis. The cold side of the temperature-activity curves of all four strains were different from wild type. The curves of the two cryophilic strains (EH65 and EH67) were shifted to colder temperatures. The curves of the other two mutant strains were shifted to warmer temperatures. In tests of chemotaxis to a variety of stimuli, strain EH61 made no response to any, EH71 made weak responses to all, and the remaining two strains made responses equal to wild type except for weaker responses to three chemical stimuli. It is concluded that thermotaxis shares specific gene requirements with processes controlling both thermal limits and sensory reception.  相似文献   
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The objective was to improve the protocol that was used to obtain the first reported piglets from transferred vitrified and warmed zona-intact blastocysts. Blastocysts were collected from superovulated sows and gilts, centrifuged to polarize lipid, vitrified, warmed and cultured for 24h or transferred immediately. Removing the zona pellucida after warming increased the number of cells in the surviving blastocysts (zona-free 60.8+/-4.3, zona-intact 39.1+/-2.8; P<0.05). Thinning the zona pellucida produced similar results to zona removal. Changing the basal medium of the vitrification and warming solutions from modified PBS to phosphate buffered NCSU-23 increased the number of cells (44.7+/-2.2 versus 56.0+/-3.9, respectively; P<0.05). Reducing the plunge temperature of the liquid nitrogen from -196 degrees C to less than -204 degrees C improved the embryo survival rate (61.9% versus 82.9%, respectively; P<0.05). These modifications were incorporated into the vitrification protocol that was used to vitrify and warm 105 blastocysts (that were subsequently transferred into four recipients). Three recipients became pregnant, farrowing three litters (average litter size, 5.3; 18.8% embryo survival in farrowing sows). Changing the warming protocol to using sucrose rather than ethylene glycol resulted in a trend towards improved embryo survival (73.5% versus 91.2%) but this was not statistically significant. Incorporating this modification, 203 blastocysts were vitrified, warmed and transferred into seven recipients. Five became pregnant and 36 fetuses were recovered (average litter size 7.2; 24.8% embryo survival in pregnant sows) at Day 40 of pregnancy. In conclusion, changes made to the vitrification protocol improved pregnancy rate and in vivo embryo survival compared to an earlier study using the original protocol.  相似文献   
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In the continuing search for models which are potentially useful for experimental therapeutics and other radiobiological studies, spontaneous lymphoma in canines has been virtually ignored. These neoplasms closely resemble their histologic counterpart in humans with respect to anatomic sites of involvement and other features. We have examined the responsiveness of canine lymphoma to total-body irradiation, and objective remissions of disease have been observed.  相似文献   
40.
Nitric oxide is a mediator of many disease states. Previous studies have demonstrated that ruthenium(III) polyaminocarboxylates can react with NO to form stable complexes reducing the levels of nitrite in the culture medium of stimulated RAW264 macrophages and reverse the NO-mediated hypotension in animal models of septic shock. It was necessary to confirm that these observations were due to NO scavenging and not inhibition of the NO metabolic pathway. Using RAW264 cells it was confirmed that [Ru(H(3)dtpa)(Cl)] (AMD6221) was neither acting at the level of iNOS induction, nor as an inhibitor of iNOS by measuring iNOS mRNA by RT-PCR and protein by Western blot and enzyme activity. Using HPLC, the nitrosyl adduct of reaction of AMD6221, [Ru(H(2)dtpa)NO], was identified in the medium of stimulated RAW264 cells co-incubated with AMD6221, concomitant with a stoichiometric reduction in nitrite/nitrate levels, thus confirming that the ruthenium(III) polyaminocarboxylates exert their pharmacological effect by scavenging NO.  相似文献   
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