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1.
Spectrophotometric detection of the formation of short-lived hypomanganate(V), [KCAR-Mn(V)O43-], and manganate(VI), [KCAR-Mn(VI)O42-], intermediates has been confirmed through the oxidation of K-carrageenan (KCAR) by potassium permanganate in alkaline solutions of pH's >or= 12 using a conventional spectrophotometer. The short-lived transient species were characterized and a mechanism consistent with experimental observations is suggested.  相似文献   
2.
The present study was carried out to assess the reproductive performance of Farafra ewes—a breed with potential economic importance in the subtropics. A total of 262 ewes were categorized according to age, parity, and postpartum interval. Ewes were introduced for breeding in fall, winter and late spring seasons. Fertility, prolificacy, lamb birth weight, and ultrasonic fetal parameters were recorded. Results obtained showed that litter size was increased with age and parity. Lamb birth weight was affected by season. None of the parameters studied had a clear-cut effect on fertility. However, an interaction between season and parity was detected. Measurement of fetal size in the first half of gestation did not predict birth weight. The obtained data represents the first record of the reproductive performance of Farafra ewes in the subtropics, which could be used to anticipate their performance in different seasons.  相似文献   
3.

Background

MERS-CoV is a newly emerged human coronavirus reported closely related with HKU4 and HKU5 Bat coronaviruses. Bat and MERS corona-viruses are structurally related. Therefore, it is of interest to estimate the degree of conserved antigenic sites among them. It is of importance to elucidate the shared antigenic-sites and extent of conservation between them to understand the evolutionary dynamics of MERS-CoV.

Results

Multiple sequence alignment of the spike (S), membrane (M), enveloped (E) and nucleocapsid (N) proteins was employed to identify the sequence conservation among MERS and Bat (HKU4, HKU5) coronaviruses. We used various in silico tools to predict the conserved antigenic sites. We found that MERS-CoV shared 30 % of its S protein antigenic sites with HKU4 and 70 % with HKU5 bat-CoV. Whereas 100 % of its E, M and N protein’s antigenic sites are found to be conserved with those in HKU4 and HKU5.

Conclusion

This sharing suggests that in case of pathogenicity MERS-CoV is more closely related to HKU5 bat-CoV than HKU4 bat-CoV. The conserved epitopes indicates their evolutionary relationship and ancestry of pathogenicity.
  相似文献   
4.
Vitamins are evaluated for their role in immunity. Recently, vitamin A received a particular attention as a critical micronutrient for regulating immune system. Therefore, the present study aimed to search for new about vitamin A. Forty-eight Egyptian adults aged from 18 to 42?years old from both sexes were subjected to clinical examination and nutrition questionnaire and were screened for vitamin A by using ELISA method. Forty subjects were selected and subdivided into two groups. Group 1 with vitamin A at level >200?µg/dl consists of 10 healthy subjects. Group 2 with vitamin A deficiency at level <50?µg/dl consists of 30 subjects. Tβ4 and CD4 levels were also determined by a commercial ELISA kit. Results showed a significant decrease in serum levels of Tβ4 and CD4 in group 2 than group 1 at P < .003 and P < .019 respectively. Both of Tβ4 and CD4 had positive correlation with vitamin A level at P < .000 and P < .003 respectively as well as with each other at p < .000. We concluded that vitamin A deficiency may be influence the levels of Tβ4 and CD4.  相似文献   
5.
The objective of this study was to describe the clinical findings, semen characteristics, and testicular histopathology in male dromedary camels affected with impotentia generandi (IG). According to the history, 82.6% (38/46) of the cases were classified as primary-IG (P-IG; never been able to impregnate a female), whereas 17.4% (8/46) were classified as secondary-IG (S-IG; acquired infertility). Only one scrotal testis was observed in four cases, and no scrotal testis was observed in one case. Overall, testicular length, width, and depth were 6.46 ± 0.2, 3.41 ± 0.1, and 2.8 ± 0.08 cm, respectively. Within the P-IG males, 42.2% of the testes were classified as small, 47.9% as normal, and 9.9% as large. Within the S-IG males, 0.0% of the testes were classified as small, 80% as normal, and 20% as large. Ejaculate volume, total sperm number in the ejaculate, and sperm motility, viability, and abnormal morphology were 4.4 ± 0.3 mL, 25.7 ± 1.0 × 106, 18.7 ± 3.1%, 25.2 ± 3.4%, and 46.6 ± 3.7%, respectively. Azoospermia was observed in 30.4% of the cases, asthenospermia was observed in the 25% of the cases, and necrospermia was observed in 10% of the cases. The proportion of abnormal sperm was between 20% and 50%, and between 60% and 94% in 56.2% and 34.4% of the cases, respectively. Hypospermatogenesis, arrested spermatogenesis, Sertoli cell–only syndrome, and testicular degeneration were the main histopathological findings. In conclusion, IG in male dromedary camels appears to be related mainly to testicular dysfunction, which alters semen quality and reduces fertility.  相似文献   
6.
Several studies have investigated the correlation between central obesity and inflammatory cytokines and the anti-inflammatory cytokine adiponectin. But, the correlation between central obesity and the anti-inflammatory cytokines IL-4, IL-5 has not been studied yet. Thus, we aimed to study the IL-4 and IL-5 correlation to central obesity in adolescent Egyptian girls among proinflammatory and anti-inflammatory cytokines. The study was carried out on 86 obese adolescent girls (BMI > 95 percentile) divided into two groups according to central obesity. The group I with waist to hip ratio <0.8 as a control and group II with waist to hip ratio >0.8 (central obesity). There was a significant increase in TNF-alpha (p < 0.0001), and IL-1β (p < 0.0001), as proinflammatory cytokines in group II, as compared to their corresponding group I. Group II showed a significant increase in the anti-inflammatory cytokines IL-4 and IL-5 than group I at (p < 0.0001) and (p < 0.0005) respectively. In addition there was a significant decrease in the anti-inflammatory adiponectin and an increase in the inflammatory leptin levels in group II at (p < 0.0001) and (p < 0.0001) respectively in comparison to group I. A high positive correlation has been observed between waist to hip ratio, leptin, TNF-α, IL-1-β, IL-4 and IL-5 at (r = 0.331, p < 0.03), (r = 0.559, p < 0.001), (r = 0.435, p < 0.004), (r = 0.509, p < 0.001), (r = 0.550, p < 0.0015), in group II respectively and a high negative one with adiponectin at (r = ?0.410, p < 0.0001). We concluded that central obesity lowers adiponectin plasma level through increasing proinflammatory adipokines such as TNF-α, IL-1β, leptin. Further studies are needed to explore the positive correlation we found between central obesity and the anti-inflammatory cytokines IL-4 and IL-5 known to be associated with bronchial asthma.  相似文献   
7.
The aim of this study was to investigate uterine torsion in buffaloes, examine factors influencing the outcome of the disease, and to characterize the related alterations in blood constituents. A total of 126 buffaloes with uterine torsion were examined for stage of gestation, duration, degree, site and direction of torsion, as well as the location of the pregnant horn. Methods of correction were documented along with dam and calf survival. Blood samples were obtained from 20 buffaloes with uterine torsion and 10 healthy buffaloes for hematological and biochemical comparisons. Results showed that uterine torsion in buffaloes occurred in multi- (81.7%) and primiparous (18.3%), during late pregnancy (58.4%) and at full term (41.6%), clockwise (96%) and counter- clockwise (4%), at post- (98.4%) and precervical (1.6%), and was of high (52.3%), moderate (31%) and mild (16.7%) degrees. Torsion was predominantly (P=0.01) on same direction of the pregnant horn. Fetal and maternal mortalities occurred in 78.6% and 23.8% of the cases, respectively. The stage of pregnancy, and degree and duration of uterine torsion were major risk factors for fetal mortality (P=0.0001), while the stage of pregnancy and fetal viability were important risk factors for maternal mortality (P<0.05). There were significant (P<0.05) increases in monocytes, albumin, aspartate aminotransferase, creatine phosphokinase, blood urea nitrogen, and phosphorus and decreases in mean corpuscular hemoglobin concentration and globulin in the affected buffaloes. Time of occurrence and duration of torsion affected some of these parameters. Uterine torsion appears to be a serious problem in buffaloes that has certain peculiarities including time of occurrence, site and direction of torsion, and the high mortality rates. Uterine torsion adversely affects liver and kidney functions. Multiparous might be at greater risk of uterine torsion. The stage of pregnancy, as well as degree and duration of uterine torsion are risk factors for fetal and maternal mortalities.  相似文献   
8.
9.
Ali A  Derar R  Hussein H 《Theriogenology》2006,66(2):463-469
This study was undertaken to describe the development of individual follicles and corpora lutea (CL) in Ossimi ewe lambs at different seasons of the year in the subtropics. Seven ewe lambs underwent daily ultrasonographic examination for 20 interovulatory periods (IOP) during spring, winter and autumn. Ovarian follicles >or=2 mm and corpora lutea were counted and measured. Blood samples were taken for progesterone (P(4)) analysis. All ewe lambs included, but one, were cyclic in all seasons studied. Three (65%) and two (35%) follicular waves were detected per estrous cycle. None of the characteristics of the large follicles was affected by season. Follicles >or=2 mm in diameter were significantly higher in winter. The CL developed slowly in autumn. Serum P(4) level was higher in autumn. Double ovulation was observed only in autumn. The data demonstrated that Ossimi sheep in the subtropics were cyclic in most seasons of the year. Season affected mainly the luteal functions with little influences on the follicular characteristics.  相似文献   
10.
Derar DR  Hussein HA  Ali A 《Theriogenology》2012,77(2):459-465
The aim of the present study was to characterize the dynamic changes of the testes and the pelvic genitalia in vivo in male dromedary. Eighty-one clinically healthy male dromedaries aged 1.5 to 12 years were assigned for the present study. Testicular length, breadth, and depth as well as epididymal head and tail were measured using caliper and ultrasonography. The pelvic genitalia, including bulbourethral gland, prostate, and pelvic urethra were examined using ultrasonography. The results revealed that the three dimensions of the testes and epididymal tail and head showed significant increase with age (P < 0.01). Concerning the epididymal measurements, differences between the pre- and peri-pubertal groups were not significant. Left testes tended to be larger than the right (not statistically significant) although only the breadth of the left testes in the prepubertal group was significantly larger (P < 0.05). The volume of both testes correlated positively with the age (r2 = 0.91 for left and 1.00 for the right, P < 0.01). There were no significant correlations between the values measured using caliper and those by ultrasonography between groups, but the correlation was highly significant (P < 0.01) for the total number of the examined animals. There were significant and steady increases of the size of bulbourethral gland in all examined groups (P < 0.01). Pars disseminata of the prostate gland and pelvic urethra were significantly higher in sexually mature compared with prepubertal groups (P < 0.01). It was concluded that ultrasonography is a useful tool in studying the developmental changes of the testes and accessory glands of the male dromedary. The obtained data could provide a reference values for predicting camel puberty and future fertility.  相似文献   
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