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71.
Rajarajan K. Uthappa A. R. Handa A. K. Chavan S. B. Vishnu R. Shrivastava A. Handa A. Rana M. Sahu S. Kumar N. Singh A. K. Ahmed S. Rana M. 《Genetic Resources and Crop Evolution》2022,69(1):71-83
Genetic Resources and Crop Evolution - For the estimation of genetic diversity and population structure, 23 accessions of Leucaena leucocephala were characterized using morphological and molecular... 相似文献
72.
Sanjay K. Sharma Ankita Sharma Surinder Rana Naveen Kumar 《Journal of plant nutrition》2018,41(6):782-792
Sixty soil samples (0–0.15 m depth) collected randomly from different districts of Himachal Pradesh were used to evaluate ammonium bicarbonate-diethylenetriaminepenta acetic acid (AB-DTPA) and acid ammonium acetate-ethylene diamine tetra acetic acid (AAAc-EDTA) over standard methods for P, K, and micronutrient cations. Among Olsen P, Bray P1, AB-DTPA P, and AAAc-EDTA P, available P (kg ha?1) varied from 7.8 to 44.3, 9.5 to 61.1, 6.5 to 38.8, 10.5 to 52.1; available K (kg ha?1) among NH4OAc, AB-DTPA, and AAAc-EDTA ranged from 103.6 to 372.3, 86.6 to 364.9, and 74.6 to 362.5. In case of micronutrients cations, AB-DTPA in general, extracted more amounts as compared to DTPA alone. AAAc-EDTA correlated highly with the Olsen P. AB-DTPA-K and AAAc-EDTA-K correlated well with standard method (NH4OAc) however; AAAc-EDTA had higher correlation with AB-DTPA for K extractability. Among methods for micronutrients highest significant correlations were observed between AB-DTPA and DTPA for Cu, Fe, and Zn. 相似文献
73.
74.
Daher RK Filion G Tan SG Dallaire-Dufresne S Paquet VE Charette SJ 《Veterinary microbiology》2011,152(3-4):353-360
Aeromonas salmonicida, a fish pathogen, is the causative agent of furunculosis. It was already shown that growing this bacterium in stressful conditions such as temperature above 22°C might lead to virulence attenuation. Unfortunately, many veterinary microbiology services and reference centers still routinely cultivate A. salmonicida at 25°C. Here we tested the presence of virulence factors by growth on specific medium as well as the integrity of the pAsa5 plasmid, which bears an important virulence factor, the type III secretion system (TTSS), by PCR analysis in twenty strains, most of which were grown at 25°C in their laboratory of origin. The analysis revealed that strains, which encountered the more stressful growth conditions displayed the most frequent absence of A-layer protein and secreted proteolytic activity. Moreover, many strains had lost parts of the pAsa5 plasmid in which the TTSS region was almost always affected. To confirm the effect of stressful growth conditions on the plasmid, three strains with an intact pAsa5 were cultured at 25°C for two weeks. A low but significant fraction of the tested colonies displayed pAsa5 rearrangements. The rearrangement always affected the TTSS region and led to a loss of virulence in the Dictyostelium discoideum co-culture assay. These results demonstrate that the instability of pAsa5 did not lead to its complete loss as previously proposed but to a more complex rearrangement phenomenon and emphasizes the necessity to grow A. salmonicida in appropriate conditions to preserve the complete virulence of the bacterium. 相似文献
75.
Mst. Parvin MOSTARI Nahoko IEDA Chikaya DEURA Shiori MINABE Shunji YAMADA Yoshihisa UENOYAMA Kei-ichiro MAEDA Hiroko TSUKAMURA 《The Journal of reproduction and development》2013,59(3):266-272
Accumulating evidence suggests that the arcuate nucleus (ARC) kisspeptin/neurokinin B
(NKB)/dynorphin (KNDy) neurons play a role in estrogen negative feedback action on
pulsatile gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) release. The
present study aimed to determine if dynorphin (Dyn) is involved in estrogen negative
feedback on pulsatile GnRH/LH release. The effect of the injection of nor-binaltorphimine
(nor-BNI), a kappa-opioid receptor (KOR) antagonist, into the third cerebroventricle (3V)
on LH pulses was determined in ovariectomized (OVX) adult female rats with/without
replacement of negative feedback levels of estradiol (low E2). The mean LH
concentrations and baseline levels of LH secretion in nor-BNI-injected, low
E2-treated rats were significantly higher compared with vehicle-treated
controls. On the other hand, the nor-BNI treatment failed to affect any LH pulse
parameters in OVX rats without low E2 treatment. These results suggest that Dyn
is involved in the estrogen negative feedback regulation of pulsatile GnRH/LH release. The
low E2 treatment had no significant effect on the numbers of ARC
Pdyn (Dyn gene)-,Kiss1- and
Tac2 (NKB gene)-expressing cells. The treatment also did not affect
mRNA levels of Pdyn and Oprk1 (KOR gene) in the
ARC-median eminence region, but significantly increased the ARC kisspeptin
immunoreactivity. These findings suggest that the negative feedback level of estrogen
suppresses kisspeptin release from the ARC KNDy neurons through an unknown mechanism
without affecting the Dyn and KOR expressions in the ARC. Taken together, the present
result suggests that Dyn-KOR signaling is a part of estrogen negative feedback action on
GnRH/LH pulses by reducing the kisspeptin release in female rats. 相似文献
76.
Kumar N Jadhao SB Jha AK Kumar K Chandan NK Akhtar MS Aklakur M Kumar S Rana RS 《Fish physiology and biochemistry》2012,38(5):1343-1353
A 2-month preliminary study was conducted to delineate the effect of dietary methyl donors (choline, betaine, and lecithin) on the growth performance and metabolic status of Labeo rohita fingerlings subjected to endosulfan alone and in combination with elevated temperature. Four iso-caloric and iso-nitrogenous diets viz. basal diet, betaine-supplemented diet, choline-supplemented diet and lecithin-supplemented diet were prepared and fed to the different experimental groups throughout the experimental period as per the design. Two hundred and seventy fingerlings (average weight 7.95?±?0.04?g) were randomly distributed in six treatment groups each having three replicates. The experimental groups were as follows: fish subjected to normal water (without endosulfan) and fed with control diet (control group T(0)), fish subjected to endosulfan-treated water and fed with control diet (T(1)), fish subjected to concurrent exposure of endosulfan and elevated temperature and fed with control diet (T(2)), fish subjected to endosulfan and elevated temperature and fed with choline-supplemented diet (T(3)), fish subjected to endosulfan and temperature and fed with betaine-supplemented feed (T(4)), and fish subjected to endosulfan and temperature and fed with lecithin-supplemented feed (T(5)). The result shows that in both the groups, that is, endosulfan exposed and concurrent exposure to endosulfan and elevated temperature group of L. rohita the growth performance like percentage weight gain, feed conversion ratio and specific growth rates were significantly different (P?0.01) when fed with supplemented diet compared with control fed group. The liver LDH and MDH activity were significantly lower in lecithin, betaine, and choline fed groups. The muscle AST as well as G6PDH, AST, and ALT did not vary but liver ALT, gill and liver ATPase, intestine ALP, muscle and liver glycogen varied significantly with dietary supplementation. The liver and gill glutathione-S-transferase (GST) activities were significantly lower in methyl donors-supplemented groups and brain AChE activity showed lower inhibition in supplemented groups in both endosulfan alone and concurrently exposed endosulfan and temperature groups. The result obtained in this study concludes that inclusion of methyl donors, particularly lecithin and betaine in feed as nutritional supplements have potential to improve growth and stress mitigating effect in L. rohita fingerlings. 相似文献
77.
通过探索性调查,本文采用多级随机抽样的方法对孟加拉东北部地区棕榈藤企业的地区贸易模式、经济效益和销售体系进行了评估。根据总投资额,企业分为大型、小型和中型。多数企业家(36.67%)的年龄在30-40或40-50之间。在小型企业中,高学历企业主的比例最低,只有3.33%;而大型企业中的高学历企业主占13.33%成熟企业者。多数企业为小型企业,为46.67%;60%的工人为熟练工,只有40%为非熟练工。经调查,这些企业生产了14种藤产品,共为23个不同尺寸,其中包括沙发(尺寸为45cm×45cm、50cm×50cm和55cm×55cm),餐桌椅系列(4把椅子和一张桌子,或6把椅子和一张桌子)、床(1cm×2cm、1.3 cm×2.3 cm和1.5 cm×2.3 cm)、椅子(45cm×45cm和50cm×50cm)、摇椅(大、中、小)、隔板、花瓶、镜框、手工艺品、台灯、手杖、茶桌等。在大型企业中,生产最多的是椅子(45cm×45cm),而中小型企业的产品中以椅子(50cm×50cm)和手工品居多。在这3种企业中,床(1.5cm×2.3cm)的生产量最少。在大型企业中,总净效益为185 659塔卡,效益成本比为1:18,均为最高。在这3种企业中,大型企业的利润最高。 相似文献
78.
Akbar?SharifianEmail author Saeed?Farahani Parvin?Pasalar Marjan?Gharavi Omid?Aminian 《Journal of circadian rhythms》2005,3(1):15
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79.
80.
Jahangiry Leila Khazaee-Pool Maryam Mahdavi Babak Ponnet Koen Sarbakhsh Parvin 《Tropical animal health and production》2019,51(2):419-428
Tropical Animal Health and Production - The purpose of this model-based study was to identify behavioral and environmental prevention factors for brucellosis and to determine the causal linkage... 相似文献