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61.
62.
Alex. G. Shulman 《The Western journal of medicine》1974,120(4):278-281
In the past century diverticular disease of the colon has changed from being almost unknown to becoming the most common disease of the colon. Studies in Britain indicated that the pathological basis of the disease is a thickening of the colonic musculature, with diverticulosis and diverticulitis developing because of increased intracolonic pressures generated by the thickened colon wall. This pressure can be sharply reduced by increased colonic bulk. Geographical and anthropological data reveal that diverticular disease results from Western civilization''s food habits, specifically the reduced fiber content in food. There is evidence that increasing the dietary intake of fiber by the addition of bran can prevent formation of diverticula and relieve the symptoms of established disease. Large scale studies are recommended both as treatment and to further test the validity of this concept. 相似文献
63.
Stereospecific hydroxylation of 3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-trans-and 3-C-cis-(methoxycarbonylmethylene)-α-D-ribo-hexofuranose (2 and 3, respectively), with potassium permanganate in pyridine afforded 3-C-[S- and R-hydroxy-(methoxycarbonyl)methyl]-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose, (6 and 7, respectively), in a combined yield, after chromatography, of 43%. Selective formation of monomethanesulfonates (9a and 10a) and p-toluenesulfonates (9b and 10b), followed by treatment with sodium azide and reduction of the azide, afforded the methyl 2-D-(and 2-L-)(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)-glycinates (12a and 13a, respectively). Basic hydrolysis of the latter compounds yielded 2-D- and 2-L-(3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranos-3-yl)glycine (12b and 13b, respectively). The structures of the glycosyl amino acids were correlated with that of L-alanine by circular dichroism. 相似文献
64.
65.
DISTRIBUTION OF PEROXISOMES (MICROBODIES) IN THE NEPHRON OF THE RAT : A Cytochemical Study 总被引:24,自引:9,他引:15
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The distribution of peroxisomes (microbodies) in the rat nephron was studied cytochemically, using glutaraldehyde- or formaldehyde-fixed tissue, by means of α-hydroxy acid oxidase activity in light microscopy or oxidation of 3,3'-diaminobenzidine (DAB) at pH 9 in both light and electron microscopy.The two cytochemical methods show peroxisomes to be nearly sperical particles found only in cells of the proximal convoluted tubule. Lysosomes were identified in the same or parallel sections, with β-glycerophosphate or 5'-cytidylic acid as substrate. They are found in all cells of the nephron. These cytochemical methods visualize the two organelles for light microscopy; they also permit unequivocal differentiation of all kidney peroxisomes from lysosomes in electron micrographs. Peroxisomes are larger and more reactive in the cells of the pars descendens (P3 segment) of the proximal convolution, located in the outer medulla and medullary rays, than in the cells of the pars convoluta (P1 and P2 segments), situated in the cortex. In contrast, lysosomes are much smaller in the P3 segment and larger and more reactive in the P1 and P2 segments. In all cells of the proximal convolution, peroxisomes tend to be concentrated nearer the base of the cells than do lysosomes. Mitochondria in P3 cells also show low levels of DAB oxidation at pH 6, in contrast to those in P1 and P2 cells. The possibility is discussed that P3 cells possess an extramitochondrial means of oxidation in which peroxisome oxidases play an important role. 相似文献
66.
67.
Measurements of intravesical pressure, urinary flow rate, retrograde cystographic residual urine, reflux of contrast medium into the prostatic ducts, and radiological prostate size were made in 45 men with benign prostatic hypertrophy. These factors were all found to be good clinical indices of the degree of urethral resistance to micturition; on the other hand, there was no relation between the latter and the severity of symptoms. 相似文献
68.
D. C. Griffiths 《Entomologia Experimentalis et Applicata》1967,10(2):171-180
Filter-paper discs soaked in nutrient were used to study how insecticides affect the biting behaviour of wireworms. When wireworms were buried in soils treated with 3.7 ppm aldrin, Bayer (381561), N 2790 or thionazin they stopped biting several days or weeks before they died. Three out of ten wireworms slowly recovered their biting ability after being buried for 4 days in soil containing 3.7 ppm -BHC. Biting behaviour was little affected when wireworms were confined to soils containing insecticides known to be not very toxic to wireworms.Nutrient discs treated with thionazin or -BHC were bitten less often than discs containing nutrient alone. Those treated with nutrient and aldrin were bitten almost as often as nutrient discs but the wireworms later stopped biting and died.
Die wirkungen von insektiziden auf das fressverhalten von drahtwürmern (Agriotes spp.)
Zusammenfassung Um den Einfluß von Insektiziden auf das Freßverhalten von Drahtwürmern zu prüfen, wurden auf zweierlei Weise Filtrierpapierscheiben benutzt, die mit dem Nährstoff vollgesogen waren: a) durch Zumischen der Insektizide in den Boden, so daß die Drahtwürmer ihrer Kontaktwirkung nicht entgehen konnten (Bodenbehandlung), b) durch Aufbringen der Insektizide auf die Nährscheiben selbst (Scheibenbehandlung).Drahtwürmer hörten einige Tage oder Wochen vor ihrem Tode auf zu fressen, wenn sie in Böden vergraben waren, die mit 3,7 ppm Aldrin, Bayer 38156 (O-ethyl-S-p-totyl-ethyl phosphonodithioate), N 2790 (O-ethyl-S-phenyl-ethyl-phosphonodithioate) oder Thionazin behandel waren. 3 von 10 Drahtwürmern gewannen ihre Freßfähigkeit langsam wieder, nachdem sie für 4 Tage in Boden vergraben gewesen waren, der mit 3,7 ppm -BHC behandelt war. Die Freßfähigkeit wurde wenig beeinflußt, wenn die Drahtwürmer in Boden eingeschlossen wurden, der Bromophos, Dichlofenthion, Ethion oder RD 14838 (3-isopropylphenyl N-acetyl N-methylcarbamate) enthielt, von denen keines sehr giftig für Drahtwürmer ist.Wenn die Insektizide den Nahrungsscheiben zugefügt wurden, wurden die mit Thionazin oder -BHC behandelten Scheiben weniger oft befressen als diejenigen, die nur die Nahrung enthielten. Mit Nahrungsstoffen und Aldrin behandelte Scheiben wurden bereitwillig befressen, aber die Drahtwürmer hörten später zu fressen auf und starben.相似文献
69.
Studies on flavonoid metabolism. Identification of the metabolites of (+)-catechin in rat urine 总被引:3,自引:2,他引:1
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L. A. Griffiths 《The Biochemical journal》1964,92(1):173-179