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181.
The distribution of anthropometric measurements related to fatness levels is examined to determine if skewness alone accounts for the nonnormality of such measures. A mixture of two normal distributions or a single skewed distribution fit the data significantly better than a single normal in all cases. For maximum hip width, knee diameter, and weight, two skewed distributions give a better fit than one skewed distribution, rejecting the null hypothesis of a single distribution even when skewness is considered. There is evidence for three skewed component distributions for biceps skinfold. Abdomen circumference, upper arm circumference, triceps skinfold, and calf skinfold are best approximated by a one component log-normal distribution. Children and parents show slightly different patterns in skewness and kurtosis when considered separately, but differences between them do not account for the commingling found in the combined distributions. 相似文献
182.
Intestinal oxalate uptake in castrated male and female rats: evidence for altered brush border membrane composition 总被引:1,自引:0,他引:1
The intestinal uptake rate of oxalate (mumoles/h/g tissue wt.) in castrated male (CM) rats, CM rats administered estradiol, and female (F) rats was 1.8, 1.4 and 1.3 times higher than that of male rats, whereas castrated female (CF) rats and CF rats administered testosterone absorbed oxalate at a rate similar to F rats, thereby, suggesting that gonadectomy affected intestinal uptake of oxalate only in male rats The intestinal oxalate uptake rate in all the groups increased linearly with increasing oxalate concentration (0.1- 6.0 mM). Chemical composition of brush border membrane showed significant changes in the sialic acid, phospholipid and cholesterol content following castration, which may lead to ultrastructural changes in the membrane thereby, increasing the absorption of oxalate. 相似文献
183.
Summary The projections of horseradish peroxidase-filled axons from each quadrant of the retina were studied to determine whether retinal projections of goldfish are topographically organized in diencephalic target nuclei. A distinct topography of the dorsal, nasal, ventral and temporal retina exists in the lateral geniculate nucleus and in the dorsolateral optic nucleus of the thalamus. The projections of retinal quadrants show minimal spatial overlap in each of these nuclei. The suprachiasmatic nucleus of the hypothalamus is extensively innervated by ventral retinal fibers, whereas the nucleus is sparsely innervated by fibers from the other three retinal quadrants. A rudimentary topography also exists in the pretectum where the dorsal pretectal area receives projections primarily from the ventral retina and the ventral pretectal area receives projections mostly from the dorsal retina. These data show that retinal projections to some diencephalic nuclei are topographically organized.This work was supported by Research Grant EY-01426 to S.C.S. 相似文献
184.
High Levels of Resistance in Agropyron Species to Barley Yellow Dwarf and Wheat Streak Mosaic Viruses 总被引:2,自引:0,他引:2
Several Agropyron species were tested for new sources of resistance to barley yellow dwarf virus (Bydv ) and wheat streak mosaic virus (WSMV). With BYDV strain PAV, 11 of the 17 Agropyron species showed no virus transmission when plants were given access feed by viruliferous Rhopalosiphum padi. Similar trials with BYDV strain RMV (vectored by R. maidis) indicated that all plants, except susceptible control plants, remained virus free. Virus status was confirmed by enzyme-linked immunosorbent assays. When plants were mechanically inoculated with WSMV, 11 Agropyron species failed to express symptoms, while five other species showed a segregating response or had some accessions segregating and some resistant. Test results suggest that resistance to BYDV and WSMV in Agropyron species does not appear to be correlated with any specific genome of Agropyron species although most of the Agropyron species containing S genome were resistant to BYDV and WSMV. 相似文献
185.
The relationship of water deficit, actual water content, area, water loss and stomatal behaviour in leaves of different insertion levels of three members of Indian arid zoneConvolvulaceae—Merremia aegyptia, M. dissecta andIpomoea pes-caprae were measured simultaneously in the month of May, 1974, when field conditions were extremely adverse for growth. The two former species loose far more water than the latter. The values measured varied considerably with the leaf insertion levels and they reversed inI. pes-caprae when compared withMerremia species. 相似文献
186.
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188.
C N Corder J G Collins T S Brannan J Sharma 《The journal of histochemistry and cytochemistry》1977,25(1):1-8
The sorbitol pathway catalyzes the conversion of glucose to fructose via the intermediate sorbitol. It consists of aldose reductase (AR) and sorbitol dehydrogenase (SDH). In adult (44 day) kidney zones, AR was highest in the outer medulla. In substructures AR was highest in distal convoluted tubule. The AR was greatest in newborn and 8-day zones of developing rat kidney. Acute alloxan diabetes was associated with decreased AR in small arteries, but not glomeruli. The SDH was lowest in outer medulla. It was most active in glomeruli and distal convoluted tubules. The diabetic state leads to no change of SDH in arteries but an increase in glomeruli. SDH increased with development. This study demonstrates AR and SDH in substructures of the kidney. The pathway is present in developing kidney. In diabetes the enzymatic changes would tend to decrease accumulation of sorbitol. 相似文献
189.
Active and passive cation transport and L antigen hertogeneity in low potassium sheep red cells
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Several lines of experimental evidence are presented suggesting that the L antigens in low potassium (LK) sheep red cells are associated with separate Na(+)K(+) pump flux is distinct from the action of anti-L(l) on K(+) leak flux, implying that K(+) leak transport sites may not be converted into active pumps by the L antiserum. Treatment of LK red cells with trypsin completely abolished both the stimulation of K(+) pump flux and the enhancement of the rate of ouabain binding brought about by anti- L. That this effect is due to a total destruction of the L(p) determinant associated with the LK pump was evident from the complete failure of anti-L(p) to bind to trypsinized LK red cells. The L(p) antigen can be effectively protected against the trypsin attack by prior incubation with anti-L, indicating that the sites for antibody binding and trypsin action may be closely adjacent at the structural level. Trypsin treatment, however, did not interfere with anti-L(l) reducing ouabain insensitive K(+) leak influx, nor did it prevent binding of anti-L(ly), the hemolytically active L antibody which is probably identical with anti-L(l). The functional independence of the L(p) and L(l) sites was documented by the observation that anti-L(l) still reduced K(+) leak influx in LK cells with experimentally induced high potassium concentrations, at which K(+) pump flux is fully suppressed, whether or not anti-L(p) was binding to the L(p) antigen associated with the LK pump. 相似文献
190.
S. C. Sharma 《International journal of biometeorology》1982,26(3):219-224
Platelet count and adhesiveness (PA) were estimated in 87 normal lowlanders at sea level. They were randomly divided in three groups. Group A was taken to 3 660 m by air, group B by rapid road ascent and group C by road after acclimatisation enroute. Estimations were repeated serially during stay at high altitude and then on return to sea level. The subjects were divided into symptomatic and asymptomatic groups based on their score on a symptom score chart. Some subjects of the air induced group (A) developed significant symptoms and showed a significant rise in PA on days 2 and 10 of exposure. Remaining subjects of group A and all subjects of road inducted group (B and C) remained asymptomatic and showed no change in PA. No significant change in the platelet counts in any of the lowlanders was noted on exposure to high altitude. The significance of these findings is discussed. 相似文献