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111.
Kural C Kim H Syed S Goshima G Gelfand VI Selvin PR 《Science (New York, N.Y.)》2005,308(5727):1469-1472
We used fluorescence imaging with one nanometer accuracy (FIONA) to analyze organelle movement by conventional kinesin and cytoplasmic dynein in a cell. We located a green fluorescence protein (GFP)-tagged peroxisome in cultured Drosophila S2 cells to within 1.5 nanometers in 1.1 milliseconds, a 400-fold improvement in temporal resolution, sufficient to determine the average step size to be approximately 8 nanometers for both dynein and kinesin. Furthermore, we found that dynein and kinesin do not work against each other in vivo during peroxisome transport. Rather, multiple kinesins or multiple dyneins work together, producing up to 10 times the in vitro speed. 相似文献
112.
Kalyan De Davendra Kumar Krishnappa Balaganur Syed Mohammad Khursheed Naqvi 《Reproduction in domestic animals》2020,55(7):777-784
Environmental cues in the different seasons might influence the estrus and lambing percentages. The present study was conducted to assess the effect of environmental factors on estrus synchronization (ES) and artificial insemination success in sheep . During the period from 2012 to 2017, a total of 1,197 ewes of Kheri and Malpura breeds of 34 farms originating from 10 villages were synchronized for estrus and then fixed-time artificial insemination (FTAI) was done. Oestrous synchronization was done by intravaginal progesterone sponges and eCG protocol. Fixed-time cervical insemination was performed 48 and 56 hr after sponge removal in ewes exhibiting estrus, using liquid chilled semen containing 100 million sperm per dose of Patanwadi/Malpura rams. Mean sunshine hours, maximum and minimum ambient temperatures, temperature amplitude, mean relative humidity (RH), temperature-humidity index (THI), mean temperature during sponge-in to sponge-out—12-day period, sponge-out and next day, AI day and AI to next 15 days have been calculated. The estrus response and lambing percentage were higher (p < .05) when ES and FTAI were done during hot-humid with rainfall season. Successful (p < .05) ES occur when the minimum temperature was higher in cold-humid season, and the sunshine hour was higher in hot-humid with scanty rainfall season during sponge-in to sponge-out period. The success of the lambing percentage was higher (p < .05) when maximum temperature, minimum temperature, mean temperature and THI was higher on the day of AI and the next 15-day period, irrespective of the season. The success of FTAI indicates the adaptability of the local breed to tolerate the harsh climate of the hot semi-arid region without much hindrance in lambing percentages. 相似文献
113.
Overexpression of Brassica napus cytosolic fructose-1,6-bisphosphatase and sedoheptulose-1,7-bisphosphatase genes significantly enhanced tobacco growth and biomass 下载免费PDF全文
LI Yan-yan GUO Li-na LIANG Cheng-zhen MENG Zhi-gang Syed Tahira GUO San-dui ZHANG Rui 《农业科学学报》2022,21(1):49-59
Elevated activities of cytosolic fructose-1,6-bisphosphatase (cyFBPase) and sedoheptulose-1,7-bisphosphatase (SBPase) are associated with higher yields in plants. In this study, the expression levels of the cyFBPase and SBPase genes were increased by overexpressing rape (Brassica napus) cDNA in tobacco (Nicotiana tabacum) plants. The transgenic plants co-expressing cyFBPase and SBPase (TpFS), or expressing single cyFBPase (TpF) or SBPase (TpS) had 1.77-, 1.55-, 1.23-fold cyFBPase and 1.45-, 1.12-, 1.36-fold SBPase activities as compared to the wild-type (WT), respectively. Photosynthesis rates of TpF, TpS and TpFS increased 4, 20 and 25% compared with WT plants. The SBPase and cyFBPase positively regulated each other and functioned synergistically in transgenic tobacco plants. In addition, the sucrose contents of the three transgenic plants were higher than that of WT plants. The starch accumulation of the TpFS and TpS plants was improved by 53 and 37%, but slightly decreased in TpF plants. Moreover, the transgenic tobacco plants harbouring SBPase and/or cyFBPase genes showed improvements in their growth, biomass, dry weight, plant height, stem diameter, leaf size, flower number, and pod weight. In conclusion, co-expression of SBPase and cyFBPase may pave a new way for improving crop yield in agricultural applications. 相似文献
114.
Yuan Yifan Miao Yuxin Yuan Fei Ata-UI-Karim Syed Tahir Liu Xiaojun Tian Yongchao Zhu Yan Cao Weixing Cao Qiang 《Precision Agriculture》2022,23(2):538-558
Precision Agriculture - Soil nutrients vary greatly and information regarding their spatial-temporal variability is critical for achieving site-specific nutrient management. However, the problem is... 相似文献
115.
Shabir A. Bangroo Nayar A. Kirmani Mohammad A. Bhat Javaid A. Wani Asif M. Iqbal Zahoor A. Dar Syed Sheraz Mahdi Ajaz A. Malik 《植物养料与土壤学杂志》2021,184(1):112-122
Background : Potassium (K) availability in soil and plant uptake is restrained by the dynamic interactions among the different pools of K. Aims : To understand these interactions, a study was undertaken to assess the quantity–intensity (Q/I) and buffering characteristics of rainfed maize (Zea mays L.) growing soils. Ten contrasting soils were evaluated for K partitioning changes in exchangeable K (ΔEK) and non‐exchangeable K (ΔNEK) pools in the soil‐solution phase and buffering characteristics using a modified version of Q/I approach. Results : The partitioned Q/I isotherms showed strong adsorption with the increase in K concentration ratio (CRK) and the changes due to ΔEK were higher than changes due to ΔNEK. Total buffering capacity (PBCK) significantly correlated (r = 0.92, p <0.01) with clay content with a major share contributed by buffering capacity owing to non‐exchangeable K ( ) rather than exchangeable K ( ). The fixation capacity (β) factor, the magnitude of added K converted into a non‐exchangeable pool, ranged from 41 to 63%, whereas release (α) factor, the magnitude of added K converted to the exchangeable pool, ranged from 19 to 36%. Both threshold solution K (CKr) and threshold exchangeable K (EKr) values were found to be high in Satran clay loam (S2) and lower in Doon silty clay loam (S3) soils. The equilibrium exchangeable K (EKo) was found close to minimum exchangeable K (Emin) in Doon silty clay loam (S3) and Babaweyl sandy clay loam (S1) soils and overall Emin constituted about 8.94 to 0.57% of the EKo. Conclusion : It may be concluded that K Q/I isotherm partitioning provides a valuable insight to assess the dynamic relations. The ratio of α/β (K recharge index) could be used to evaluate the K enrichment capacity of soil to K additions while EKr and Emin can be potentially useful in the elucidation of exchangeable K as K fertility index especially in soils with poor K fertilizer management. 相似文献
116.
Eric Monnet E. Christopher Orton Mo Salman June Boon 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(1):12-17
To further define the prognosis and identify clinical findings predictive for survival in dogs with dilated cardiomyopathy (DCM), we performed Kaplan Meier survival analysis of 37 dogs with idiopathic DCM. Survival analysis showed that the 50% probability of survival occurred at 2.3 months. Probability of survival at 1 year was 37.5% and at 2 years was 28%. Bivariate Cox proportional hazard ratios identified pleural effusion and pulmonary edema, both signs of congestive heart failure, as independent prognostic indicators for dogs with DCM ( P < .01). Hazard ratios for these prognostic indicators were 2.354 and 3.291, respectively. Multivariate Cox stepwise regression identified pleural effusion, left ventricular free-wall thickening fraction, ventricular ectopy, and weight loss as significant prognostic indicators for dogs with DCM. Because of the retrospective nature of this study, the effects of different drug treatments were not evaluated. The type of cardiac-related death, progressive failure versus sudden death, was not addressed in this study and requires further evaluation. 相似文献
117.
118.
Platelet Hyperfunction in Dogs With Malignancies 总被引:1,自引:1,他引:0
Elizabeth A. McNiel Gregory K. Ogilvie DVM Martin J. Fettman Mowafak D. Salman 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(3):178-182
In vitro platelet aggregometry was performed on whole blood samples from 59 dogs with malignancies and 24 control dogs. Three reagents were used for the aggregation studies: collagen, arachidonic acid, and adenosine diphos-phate (ADP). The parameters measured to evaluate response to collagen included delay in the aggregation response, slope of the aggregation curve, maximum aggregation, and adenosine triphosphate (ATP) secretion. The platelets of dogs with malignancies exhibited significantly ( P < .05) shorter delays in the aggregation response, higher maximum aggregation, and higher ATP secretion when compared to control dogs. For the weaker reagents, ADP and arachidonic acid, the lowest concentration resulting in aggregation was determined. Platelets of dogs with malignancies tended to aggregate in response to lower concentrations of ADP than did those of controls ( P < .05). The response of platelets to the concentrations of arachidonic acid employed in this study was poor, with few samples achieving measurable aggregation. The findings of this study suggest that dogs with malignancies have hyperaggregable platelets. 相似文献
119.
Harvey N Reeves A Schoenbaum MA Zagmutt-Vergara FJ Dubé C Hill AE Corso BA McNab WB Cartwright CI Salman MD 《Preventive veterinary medicine》2007,82(3-4):176-197
The North American Animal Disease Spread Model is a stochastic, spatial, state-transition simulation model for the spread of highly contagious diseases of animals. It was developed with broad international support to assist policy development and decision making involving disease incursions. User-established parameters define model behavior in terms of disease progression; disease spread by animal-to-animal contact, contact with contaminated personnel or equipment, and airborne dissemination; and the implementation of control measures such as destruction and vaccination. Resources available to implement disease control strategies, as well as the direct costs associated with these strategies, are taken into consideration. The model records a wide variety of measures of the extent of simulated outbreaks and other characteristics. The graphical interface and output visualization features also make it a useful tool for training and preparedness exercises. This model is now being used to evaluate outbreak scenarios and potential control strategies for several economically important exotic animal diseases in the United States, Canada, and elsewhere. NAADSM is freely available via the Internet at http://www.naadsm.org. 相似文献
120.
During a survey on Myxobolus infection of pond-cultured common carp in Syria three Myxobolus spp. were found. Myxobolus dispar infected the gill arteries, forming large elongated plasmodia in the gill filaments. The plasmodia of M basilamellaris were located in the gill arches at the base of the filaments. Elongated filiform plasmodia of M. encephalicus were found in the blood vessels of the brain. Despite the common occurrence of the above parasites, no disease symptoms were observed in the infected fish specimens. This is the first report on myxosporean infection of fish from Syrian waters. 相似文献