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41.
42.
Six green leafy vegetables and herbs – spinach, amaranth, bengal gram, cauliflower, mint, coriander and carrots – were analyzed for moisture, protein,ascorbic acid, -carotene, total iron, ionizable iron (as % of total iron) in vitro iron (% of total iron), copper, manganese and zinc. Moisture content of the leaves and carrots varied from 75.1 percent (bengal gram) to 95.4 percent (carrot) and protein from 9.83 percent (carrots) to 30.9 (mint) percent. Ascorbic acid, -carotene, total iron and ionizable iron contents were at a maximum in case of bengal gram leaves whereas level of ionizable iron and in vitro iron as a percent of total iron was highest in carrots. Copper, manganese and zinc contents were maximum in spinach.  相似文献   
43.
OBJECTIVES: A study was conducted among the Onge tribe of the Andaman and Nicobar Islands with the objectives of identifying demographic factors responsible for the decline in their population and assessing their nutritional status, which is an important determinant of child survival. STUDY DESIGN AND SUBJECTS: The study included estimation of indices of fertility and child mortality, and assessment of nutritional status. All individuals of the Onge community settled on Little Andaman Island were included. RESULTS: The mean total marital fertility rate was estimated to be 5.15 live births per woman and the general fertility rate was 200 live births per 1000 married-woman-years. Although the gross reproduction rate was estimated to be 2.2 female children per married woman, the net reproduction rate was only 0.9 surviving female child per married woman. The mean infant mortality rate during the past 30 years was 192.7 per 1000 live births, and the child survival rate was found to be only 53.2%. A mild to moderate degree of malnutrition was found in 85% of children of pre-school age and severe malnutrition in 10%. The Onges had low intakes of iron, vitamin A and vitamin C. All the screened Onges were found to be infested with one or more intestinal parasites. CONCLUSIONS: High childhood mortality appears to be the predominant demographic factor responsible for the decline in the Onge population. The high prevalence of undernutrition and micronutrient deficiency disorders could be important factors contributing to the high childhood mortality.  相似文献   
44.
Taxus wallichiana is one of the most important medicinal tree species of the Himalayan region. Leaf and bark of the species yield an important drug called taxol, which is used for treatment of many types of cancer. There is a serious threat to the existence of the species due to over exploitation in its native habitat. Adequate information on the nature and the extent of genetic diversity in this important species is required for developing suitable strategy for its conservation. Random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) were used to assess genetic variation in nine natural populations of T. wallichiana from western part of the Himalayan ranges. Both the markers revealed low genetic diversity in these populations. Average heterozygosity for AFLP and RAPD were 0.3715 and 0.3072, respectively. ΦST values derived from molecular variance were 0.0855 and 0.1005 for AFLP and RAPD, respectively, whereas the corresponding GST values were 0.1796 and 0.2140. Most part of the genetic variation was present within the populations. However, between population variation was low but statistically significant, which suggested that the sampled populations might not constitute a single panmictic population. Cluster analysis and Mantel’s correlation revealed that genetic differentiation broadly followed geographic distribution of the populations. T. wallichiana thus urgently needs to be conserved using both in situ and ex situ conservation approaches.  相似文献   
45.
Sleep is an essential process conserved from flies to humans. The importance of sleep is underscored by its tight homeostatic control. Through a forward genetic screen, we identified a gene, sleepless, required for sleep in Drosophila. The sleepless gene encodes a brain-enriched, glycosylphosphatidylinositol-anchored protein. Loss of SLEEPLESS protein caused an extreme (>80%) reduction in sleep; a moderate reduction in SLEEPLESS had minimal effects on baseline sleep but markedly reduced the amount of recovery sleep after sleep deprivation. Genetic and molecular analyses revealed that quiver, a mutation that impairs Shaker-dependent potassium current, is an allele of sleepless. Consistent with this finding, Shaker protein levels were reduced in sleepless mutants. We propose that SLEEPLESS is a signaling molecule that connects sleep drive to lowered membrane excitability.  相似文献   
46.
Three vegetables, 5 roots and tubers, 23 fruits and 3 stored products collected and consumed by tribals of Andhra Pradesh, India were analyzed for total carotenoids (TC) and Beta carotene (BC) contents using High Performance Liquid Chromatography (HPLC). The vitamin A activity expressed as retinol equivalents (RE) was calculated based on the in vivo conversion factor given by WHO. The results of the study indicated that the vegetables, roots and tubers analyzed showed negligible vitamin A activity with TC and BC content ranging from 0.01 to 0.61 and 0.14 to 0.23 mg%, respectively. Among the fruits, Canthium parviflorum contained very high TC (9.51 mg%) and BC (6.10 mg%) contents, and the edible orange color fresh rind portion analyzed had the highest (6.8 mg%) BC content. Other fruits contained negligible content of TC (0.0015 to 1.32 mg%) and BC (0.004 to 0.49 mg%). The edible pulp portion of the fruit (Diosphros melanoxylon contained no BC but the rind portion analyzed fresh and dried had BC) 0.79 and 2.17 mg%, respectively. Tribals were found to have distinct attitudes and beliefs towards food they use or avoid in certain physiological conditions.  相似文献   
47.
In the present investigation, four weaning foods were formulated using locally available cereals and pulses such as wheat (Triticum aestivum), barley (Hordeum vulgare) and green gram (Vigna radiata). Cereal, pulse and jaggery were used in the proportion of 70:30:25. Domestic processing technique like roasting and malting were used to process cereals and pulses for development of weaning foods. All the four blends had a nutrient composition within the range prescribed by the Indian Standard Institute (ISI) for processed weaning foods. The processing of grains resulted in 16–20% increase in starch digestibility and 17–32% increase in protein digestibility. Also 16–32% increase in iron availability was observed on processing. The effect was more remarkable in malted weaning foods as compared to roasted ones.  相似文献   
48.
Most of the salt-affected soils of the Indo-Gangetic plain in NW India do not find suitable places in the 1970 U.S. system of soil classification. According to the current class definitions, soils with high salts, ESP, pH, chromas and yellower hues key out as Typic or Aquic Calciorthids, Camborthids and Haplustalfs which does not spell out their saline-sodic nature. For land-use recommendations, the authors believe it will be useful to set these soils apart at some high categoric level in the system.It is proposed that the structural requirements for the natric horizon be modified to include horizons with high ESP (? 40) but having simple blocky structure with or without tongues of eluvial material. New subgroups, viz. Natric, within the orders of Inceptisols, Alfisols and Aridisols is suggested for the high sodium-saturated soils lacking natric horizons. For similar practical considerations, the high concentrations of salts in soils when associated with high ESP pose problems in leaching and consequently new subgroups, viz. Salic and Salic Natric, within the orders of Aridisols and Alfisols are suggested.The modifications proposed not only place more emphasis on the saline-sodic nature of these soils but also result in better groupings for practical land use.  相似文献   
49.
Gene transfer and molecular cloning of the human NGF receptor   总被引:34,自引:0,他引:34  
Nerve growth factor (NGF) and its receptor are important in the development of cells derived from the neural crest. Mouse L cell transformants have been generated that stably express the human NGF receptor gene transfer with total human DNA. Affinity cross-linking, metabolic labeling and immunoprecipitation, and equilibrium binding with 125I-labeled NGF revealed that this NGF receptor had the same size and binding characteristics as the receptor from human melanoma cells and rat PC12 cells. The sequences encoding the NGF receptor were molecularly cloned using the human Alu repetitive sequence as a probe. A cosmid clone that contained the human NGF receptor gene allowed efficient transfection and expression of the receptor.  相似文献   
50.
Macaque monkeys with the recently described acquired immunodeficiency syndrome show a marked defect in T-lymphocyte function and die with opportunistic infections and lymphoproliferative abnormalities. In the study described here a new type D retrovirus was isolated from two Macaca cyclopis with this syndrome. This virus is related to, but distinct from, Mason-Pfizer monkey virus, a type D retrovirus previously isolated from a mammary tumor of a rhesus monkey (Macaca mulatta).  相似文献   
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