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911.
Basal and pentagastrin-stimulated peak acid outputs were determined in 21 subjects with chronic atrophic gastritis and 10 subjects with chronic superficial gastritis. All subjects were Caucasian. The histological diagnosis was based on multiple gastric biopsy specimens obtained through a fibregastroscope. Comparison of the results with those of a previously reported Caucasian control group show that the mean basal acid outputs of subjects with chronic (superficial) gastritis were significantly higher than that of controls and subjects with chronic atrophic gastritis. No significant difference was found in the mean peak acid outputs of controls and subjects with chronic atrophic gastritis or chronic (superficial) gastritis. 相似文献
912.
913.
LR Blaisdell 《Canadian Metallurgical Quarterly》1995,85(11):48-50, 52-4
914.
PURPOSE: To obtain longitudinal data to estimate long-term morphometric changes in normal human corneal endothelia. METHODS: Ten years after an initial study, the authors rephotographed the central corneal endothelium of 52 normal subjects with the same contact specular microscope. The findings for the 10 subjects younger than 18 years of age at the initial examination were considered separately. For the remaining 42 adult subjects, the time between examinations averaged 10.6 +/- 0.2 years (range, 10.1 to 11 years). At the recent examination, these subjects' ages averaged 59.5 +/- 16.8 years (range, 30 to 84 years). Outlines of 100 cells for each cornea were digitized. RESULTS: For the 42 adult subjects, the mean endothelial cell density decreased during the 10.6-year interval from 2715 +/- 301 cells/mm2 to 2539 +/- 284 cells/mm2 (P < 0.001). The calculated exponential cell loss rate over this interval was 0.6% +/- 0.5% per year. There was no statistically significant correlation between cell loss rate and age. During the 10.6-year interval, the coefficient of variation of cell area increased from 0.26 +/- 0.05 to 0.29 +/- 0.06 (P < 0.001), and the percentage of hexagonal cells decreased from 67% +/- 8% to 64% +/- 6% (P = 0.003). For the 10 subjects 5 to 15 years of age at the initial examination, the exponential cell loss rate was 1.1% +/- 0.8% per year. CONCLUSIONS: Human central endothelial cell density decreases at an average rate of approximately 0.6% per year in normal corneas throughout adult life, with gradual increases in polymegethism and pleomorphism. 相似文献
915.
916.
The following relations were derived from large-scale testing of feed protein quality and its bearings on testicular function in growing Wistar rats: testicle weights and live weights r = 0.77 for juvenile animals and r = 0.36 for adult animals; nuclear volumes of Leydig's cells to testicle weights r = 0.84 for juvenile animals and r = 0.43 for adult animals; testosterone in testicular tissue, ng/g, to testicle weights r = 0.55 for juvenile animals and r = 0.80 for adult animals; testosterone per live weight, ng/100 g, to nuclear volumes of Leydig's cells r = 0.76 for juvenile animals and r = 0.46 for adult animals. Critical thresholds above which complete spermatogenesis is always ensured may be established for testosterone (50+/-5 ng/100 g live weight) and for the nuclear volume of Leydig's cells (30 mum3). Another conclusions drawn from the above results is that high testosterone levels in the testes of adult animals were not attributable to high testosterone biogenesis of Leydig's cells, as might have been assumed from high activities of that kind recordable from some nuclear volumes. 相似文献
917.
LR Olivier FJ Retief D Bester JS du Plessis JR Kriel 《Canadian Metallurgical Quarterly》1977,52(15):607-609
Primary prevention is now the first priority of research on smoking. A study was made of 1 505 children of 12 high schools situated in a conservative Afrikaans-speaking community in an attempt to determine the characteristics of the smoking and non-smoking groups. Of the total group 16% were smokers. The male/female ratio was 3:1. The mean age at which smoking commenced was 15,5 years. A positive relationship was found between the smoking habits of the smokers and those of their parents and best friends. The majority of pupils think that smoking is addictive. In addition, they believe that it is unhealthy and leads to poor sporting achievements. The great majority of smokers and non-smokers agree that non-smokers do better at school. Fathers of both smokers and non-smokers do not favour the habit. Ninety per cent of the boys and 83% of the girls started smoking between 12 and 18 years of age. The critical age for a preventive programme is thus 11 years. 相似文献
918.
Mapping the locus of the H-Y gene on the human Y chromosome 总被引:2,自引:0,他引:2
GC Koo SS Wachtel K Krupen-Brown LR Mittl WR Breg M Genel IM Rosenthal DS Borgaonkar AD Miller R Tantravahi RR Schreck BF Erlanger OJ Miller 《Canadian Metallurgical Quarterly》1977,198(4320):940-942
The H-Y locus is on the short arm of the human Y chromosome in most individuals but on the long arm in at least one of 17 individuals with structural abnormalities of the Y. 相似文献
919.
LR Prosnitz LR Farber JJ Fischer JR Bertino DB Fischer 《Canadian Metallurgical Quarterly》1976,37(6):2826-2833
A new treatment program for advanced Hodgkin's disease employing five-drug combination chemotherapy and low dose radiation to the sites of bulk disease (nodal or parenchymal) was designed in 1969. Eighty patients have now been treated, 60 of whom have achieved a complete remission. More significantly, only 5 of the 60 completed responders have relapsed with follow-up from 1-6 years. The cumulative survival at 5 years of patients entering complete remission is 92%. For those patients not sustaining a complete remission, it is 19% at 2 years. This program has resulted in substantially lower relapse rates than previously reported by other investigators, probably because of the administration of radiotherapy in the manner described. Hopefully, a significant number of these patients may be cured of their disease. 相似文献
920.
JF Bureau KM Drescher LR Pease T Vikoren M Delcroix L Zoecklein M Brahic M Rodriguez 《Canadian Metallurgical Quarterly》1998,148(4):1941-1949
Theiler's murine encephalomyelitis virus causes a chronic demyelinating disease in susceptible strains of mice that is similar to human multiple sclerosis. Several nonmajor histocompatibility complex-linked genes have been implicated as determinants of susceptibility or resistance to either demyelination or virus persistence. In this study, we used linkage analysis of major histocompatibility complex identical H-2d (DBA/2J x B10.D2) F2 intercross mice to identify loci associated with susceptibility to virus-induced demyelinating disease. In a 20-cM region on chromosome 14, we identified four markers, D14Mit54, D14Mit60, D14Mit61, and D14Mit90 that are significantly associated with demyelination. Because two peaks were identified, one near D14Mit54 and one near D14Mit90, it is possible that two loci in this region are involved in controlling demyelination. 相似文献