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61.

Background  

Some medical disorders have higher prevalence in shift workers than others. This study was designed to evaluate the effect of night-shift-working on total plasma antioxidant capacity, with respect to the causative role of oxidative stress in induction of some of these disorders.  相似文献   
62.
The nutritive value of some commercial wheat varieties grown in Pakistan was measured chemically, including amino acid analysis, and biologically in N-balance experiments with growing rats. The protein content ranged from 13.2% in Punjab-83 to 16% in Barani-83. Lysine per 100g protein varied between 2.46 and 2.75%. The available carbohydrate ranged from 67.3 to 74.7%. Iron content was highest in Sonalika while the concentration of zinc and manganese was highest in Sarhad-82. The protein digestibility (TD), biological value (BV) and net protein utilisation (NPU) varied between 92–95%, 56–68% and 53–65% respectively. Level of wheat protein was negatively correlated with available carbohydrate (r=–0.93), lysine per unit protein (r=–0.67) and BV (r=–0.76). The lysine content (g/16gN) of commercial wheat varieties showed a positive correlation (r=+0.95) with the BV. The protein quality was lowered in varieties having higher content of protein.  相似文献   
63.
Egg quality, those characteristics of the egg that determine its capacity to survive, is a significant problem for many species of fish currently being farmed. Little is known about the determinants of egg quality and there is little agreement regarding reliable methods for its assessment. To be of practical benefit, assessments should be simple to perform and should be carried out as early in development as is possible. Fertilization rates are often used as measures of quality. For the Atlantic halibut Hippoglossus hippoglossus, fertilization rate and assessments of cell symmetry at early cleavage stages provide reasonable indicators of quality. Regardless of assessment method, it is strongly recommended that performance data from all batches of each broodfish be examined when surveying the overall quality of a stock. The misleading effects of pooling such information are demonstrated for a rainbow trout Oncorhynchus mykiss broodstock. Although a large number of factors have been implicated as possible determinants of egg quality, only 1) bacterial colonization of the eggs, 2) nutritional status of the broodfish and, 3) overripening, the process of aging that occurs when eggs are retained within the broodfish after ovulation, have been clearly shown to affect egg quality. The effect of overripening on fish egg quality is discussed in detail. Species-specific differences in the time scale of overripening are pointed out and related to spawning strategy and water temperature. Rainbow trout eggs and those of other salmonids should be fertilized within approximately one week of ovulation. Overripening proceeds much more rapidly in warm water species, e.g., tilapia eggs must be fertilized within an hour or so of ovulation. Egg viability also decreases rapidly for batch spawning species. Fertilization data are presented for Atlantic halibut demonstrating that egg quality decreases 4–6 h after ovulation. The rate of overripening was comparable for eggs held in vitro in ovarian fluid to those retained within the ovarian lumen. These halibut data, combined with information from other marine and freshwater fish, indicate that overripening is a significant determinant of egg quality for many if not all fish.  相似文献   
64.
OBJECTIVE: To assess rates of initiation of breast-feeding and exclusive breast-feeding within 2 months after delivery and to determine the factors influencing exclusive breast-feeding. DESIGN: A health worker-administered questionnaire survey was carried out during the time period 1 August-30 September 2005. SETTING: Immunisation clinics of Pokhara, a submetropolitan city in western Nepal. SUBJECTS: Three hundred and eighty-five mothers who had delivered a child within the previous 2 months. RESULTS: The rates of initiation within 1 h and within 24 h of delivery were 72.7 and 84.4%, respectively. Within 2 months after delivery, exclusive breast-feeding was practised by 82.3% of the mothers. Breast milk/colostrum was given as the first feed to 332 (86.2%) babies but 17.2% of them were either given expressed breast milk or were put to the breast of another lactating mother. Pre-lacteal feeds were given to 14% of the babies. The common pre-lacteal feeds given were formula feeds (6.2%), sugar water (5.9%) and cow's milk (2.8%). Complementary feeds were introduced by 12.7% of the mothers. By logistic regression analysis, friends' feeding practices, type of delivery and baby's first feed were the factors influencing exclusive breast-feeding practice of the mothers. CONCLUSIONS: Despite the higher rates of initiation and exclusive breast-feeding, practices such as pre-lacteal feeds and premature introduction of complementary feeds are of great concern in this urban population. There is a need for promotion of good breast-feeding practices among expectant mothers and also the community, especially the families, taking into account the local traditions and customs.  相似文献   
65.
66.
OBJECTIVE: To identify a technique for measurement of glycated hemoglobin percentage in blood samples obtained from various species of nonhuman primates (NHPs), to determine whether these percentages varied with respect to glycemic control, and to assess whether this physiologic variable provided a suitable test for diagnosing diabetes mellitus in NHPs. SAMPLE POPULATION: 166 blood samples collected from 121 NHPs comprising 22 species from the Haplorhine and Strepsirhine suborders and including nondiabetic, treated-diabetic, and diabetic animals in 23 zoologic institutions throughout the United States. PROCEDURE: Hemoglobin A1c percentage was measured in 154 samples by use of high-performance liquid chromatography. Total glycated hemoglobin percentage was measured in 159 samples by use of a boronate-affinity chromatographic assay. Glucose concentration was measured in 157 samples with an autochemical analyzer by use of a hexose kinase method. RESULTS: The boronate-affinity chromatographic technique for measurement of total glycated hemoglobin percentage was the most suitable method. Nondiabetic Haplorhines had percentages higher than those in nondiabetic Strepsirhines. In Haplorhines, diabetic animals had percentages higher than those in treated-diabetic animals, which had percentages higher than those in nondiabetic animals. In Strepsirhines, this pattern was less pronounced. CONCLUSIONS AND CLINICAL RELEVANCE: Measurement of total glycated hemoglobin percentage provides useful information for diagnosing diabetes mellitus in Haplorhines and, possibly, in Strepsirhines. Until reference ranges are established for each species, it is recommended that results for samples from NHPs without clinical signs of diabetes mellitus be compared with results of samples collected concomitantly from NHPs with clinical signs of this condition.  相似文献   
67.
68.
The genus Punica (Punicaceae) is distributed in Iran, Afghanistan, India and Mediterranean countries. Iran is considered to be its primary center of origin. In India Punica granatum is found in wild only in Western Himalayan regions comprising, Jammu and Kashmir, Himachal Pradesh and Uttarakhand states. However, there is little information available about the genetic variation present in pomegranates in the regions. In this paper we describe the use of DAMD and RAPD methods that generate the profiles, to study genetic diversity in wild genotypes of the P. granatum in India. Forty-nine accessions representing two regions of Western Himalaya were analyzed. Similarity coefficient value varied from 0.08 to 0.79 across different accessions. The results indicate that DAMD (97.08%) revealed more polymorphism in comparison to RAPD (93.72%). The results show that these methods are sufficiently informative to unravel the genetic variations in wild pomegranates in Western Himalayas.  相似文献   
69.
70.
A 2-year study on the preference and performance of Lipaphis erysimi on different Brassica species in the field and under greenhouse conditions revealed that rapeseed (B. campestris var. BSH-1, B. campestris var. YSPB-9) and mustard (B. juncea RH-30) were better hosts for this aphid than other Brassica species (B. napus, B. nigra, Eruca sativa, B. carinata). On the first group of plants, the rate of nymphal development, longevity and fecundity of this pest were significantly less than on the second group of plants. Development was significantly prolonged when the aphid was reared on second group of plants.  相似文献   
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