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The highest values of consanguinity was found among “Kamma” (45.0%), “Ediga” (47.5%) and “Mala” (55.7%) who occupy different strata of Indian caste hierarchy. In the way of searchout the factors influencing consanguineous marriages, the present paper finda the negative relationship between educational levels of the spouses and consanguinity. The educational levels of men has significant effect on the frequency of consanguinious marriages among “Kamma” and “Mala”. However, further analysis deplore significant differences in the mean levels consanguinity between educational groups. It divulge low level of higher education among the populations. Only 12% of men and 1.6% of women have degree level and above education in the total sample.  相似文献   
164.
The costs of environmental remediation at leaking petroleum underground storage tank (UST) sites are influenced significantly by soil cleanup levels. The use of conservative generic soil cleanup levels may be inappropriate at some sites contaminated by leaking petroleum USTs. At many contaminated sites, a primary objective of site remediation is long‐term protection of water resources (e.g., groundwater) from pollution. Leaching of pollutants from residual soil contamination to groundwater is a primary consideration in establishing site‐specific soil cleanup levels at fuel‐contaminated sites. The use of laboratory soil leachability testing methods may be useful in objectively evaluating the leaching potential of contaminants from residual soil contamination and estimating potential groundwater impacts. Developing soil cleanup levels that are protective of water resources must include a technically sound integration of site‐specific soil leachability data and contaminant attenuation factors. Evaluation of the leaching potentials of soil contaminants may also provide essential supplementary information for other site characterization methods that may be used to evaluate risks to human health. Contaminant leachability testing of soils may provide a cost‐effective and technically based method for determining soil cleanup levels that are protective of groundwater resources at contaminated petroleum UST sites.  相似文献   
165.
Bhargava, H. N. and Y. J. Cao. Effect of chronic administration of morphine, U-50,488H and [ -Pen2, -Pen5]enkephalin on the concentration of cGMP in brain regions and spinal cord of the mouse. Peptides 18(10) 1629–1634, 1997.—The effects of chronic administration and subsequent withdrawal of μ-, κ- and δ-opioid receptor agonists on the levels of cyclic GMP in several brain regions and spinal cord of mice were determined in an attempt to further study the role of NO cascade in opioid actions. The agonists at μ-, κ- and δ-opioid receptor included morphine, U-50,488H and DPDPE, respectively. Tolerance to morphine was associated with highly significant increases in cGMP levels in corpus striatum (41%), cortex (36%), midbrain (73%) and cerebellum (51%) relative to controls. Abstinence caused increases in cGMP levels in corpus striatum (61%) and pons and medulla (45%). Tolerance to U-50,488H resulted in increases in cGMP levels in midbrain (52%) whereas abstinence from U-50,488H increased the cGMP levels in pons and medulla(76%). Tolerance to DPDPE was associated with increases in cGMP levels in hypothalamus (12%) and pons and medulla (33%) but decreases in cerebellum (66%) and spinal cord (58%). Abstinence from DPDPE produced increases in cGMP levels in pons and medulla (14%) but decreases in cerebellum (67%) and spinal cord (50%). Overall treatment with morphine and U-50,488H produced increases in cGMP levels in brain regions whereas DPDPE produced decreases in brain regions and spinal cord. Previous studies have shown that chronic administration of μ- and κ- opioid receptor agonists induce NO synthase (NOS) in certain brain regions and that the inhibitors of NO synthase attenuate tolerance to μ- and κ- but not to δ-opioid receptors agonists. Since activation of NO increases the production of cGMP, the present results demonstrating alterations of cGMP levels by μ-, κ- and δ-opioid receptor agonists are consistent with the behavioral results with NOS inhibitors on tolerance to μ-, κ- and δ-opioid receptor agonists.  相似文献   
166.
Long-term effects of 1-naphtaleneacetic acid (NAA), benzyladenine (BA), gibberellic acid (GA3), abscisic acid (ABA) and ethylene on K+ levels, K+ uptake and translocation to the shoot were studied in young wheat plants (Triticum aesticum L. cv. Martonvásári-8) grown at different K+ supplies. Na+ levels and K+/Na+ selectivity were also investigated. Both in shoots and roots, NAA, BA and ABA decreased K+ and Na+ levels more effectively in high-K+ plants than in low-K+ plants. GA, and ethylene did not influence K+ and Na+ levels. K+/Na+ selectivity in roots of low-K+ plants was increased in favour of K+ by BA, NAA and to a lesser extent by ABA. In high-K+ plants only BA increased the K+/Na+ ratio, whereas the effects of the other hormones were the opposite (NAA) or less pronounced (ABA). K+(86Rb) uptake was inhibited by NAA and BA in low-K+ plants but not in high-K+ plants. K+(86Rb) uptake was inhibited throughout by 10 μM ABA. K+(86Rb) translocation to the shoot was influenced by the hormones similarly to the uptake patterns, with the exception of ABA, which inhibited translocation in low-K+ plants but not in high-K+ plants. The results show that hormonal effects may quantitatively and qualitatively be modified by K+ levels in the plant and that internal K+ concentration may play a role in the mechanisms regulating the effects of NAA, BA and ABA but probably not in those of GA3 or ethylene.  相似文献   
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168.
This review discusses (a) how the concentration of fructose 2,6-bisphosphate is controlled in spinach leaves, (b) how fructose 2,6-bisphosphate and cytosolic metabolites control the cytosolic fructose-1,6-bisphosphatase (EC 3.1.3.11), and (c) how the activities of the fructose-1,6-bisphosphatase and of sucrose phosphate synthase (EC 2.3.1.14) are coordinated. These features provide the elements of a fine control network that regulates sucrose synthesis during photosynthesis. The rate of sucrose synthesis is coordinated with the supply of photosynthate, so that concentrations of metabolites and phosphate are maintained at a level in the chloroplast which allows rapid CO2 fixation. The rate of sucrose synthesis can also be modified to alter the amount of photosynthate that remains in the chloroplast for conversion to starch.  相似文献   
169.
The effect of drought on CO2 assimilation and leaf conductance was studied in three northern hardwood species: Quercus rubra L., Acer rubrum L. and Populus grandidentata Michx. Leaf gas exchange characteristics at two CO2 levels (320 and 620 μl I−1) and temperatures from 20 to 35°C were measured at the end of a dry period and shortly after 10 cm of rainfall. The effects of drought varied with species, temperature and CO2 level. Calculated values of internal CO2 concentration showed little or no decline during drought. Differences in assimilation, before vs after the rains, were most apparent at the higher CO2 level. These latter two observations indicate nonstomatal disruption of CO2 assimilation during the dry period. In P. grandidentata there was a substantial interaction between drought and temperature, with a resultant shift in the temperature for maximum assimilation to lower temperatures during drought. During drought, internal CO2 concentrations increased sharply in all three species under the combined conditions of high temperatures and the higher CO2 level.  相似文献   
170.
Serum from sheep was collected throughout a 30-week period of infection with Fasciola hepatica and specificity for the tissues of flukes of various ages was tested by an indirect fluorescent antibody labeling technique, using as antigen JB4 plastic-embedded sections of flukes up to 30-weeks old grown in rats. Quantitative estimates of host antibody concentration and fluke tissue antigenicity were determined by titration using serially diluted serum. Serum from early infections (pre-7 weeks) gave strong labeling over the tegument of young flukes, but the reaction became progressively weaker with older fluke tissue. This was associated with a decline in the number of T1 bodies in the tegument as revealed by electron microscopy. T1 bodies contain glycocalyx precursor substances and during development they replace the antigenically similar T0 secretory bodies characteristic of early juvenile flukes. Glycocalyx turnover may help protect the pre-bile duct flukes against immunological attack. Serum from sheep with F. hepatica infections older than 7 weeks gave moderate reaction with T2 bodies which accumulated in the tegument during the early stages of infection but only expressed their antigens on the surface about the time of entry into the host's bile ducts. The antigenicity of the gut and excretory system of flukes seemed to remain unchanged throughout adult life. Levels of host antibody specific for juvenile tegument, gut, and excretory system peaked at 3–5 weeks postinfection, and declined once the flukes entered the bile ducts. Anti-T2 antibody appeared 6 weeks postinfection and began to decline 5–6 weeks later.  相似文献   
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