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This study reports the first evaluation of sperm hyaluronan binding assay (HBA) for predicting the fertility of Nili-Ravi buffalo bulls in relation to standard parameters of sperm quality. Cryopreserved semen doses of low (n = 6), medium (n = 3) and high fertility (n = 8) bulls based on their respective return rates were used. Significantly, more spermatozoa bound to hyaluronan from the most fertile bulls (57.15% ± 1.44) compared with medium (42.46% ± 1.08) and low fertility bulls (29.70% ± 0.78). A strongly positive correlation (r = .824, p < .01) was found between HBA and fertility that predicts a 67.9% variability (r2 = .679, p < .01) in fertility. HBA was also strongly positively correlated with sperm viability (r = .679, p < .01) followed by their live/dead ratio (r = .637, p < .01), uncapacitated spermatozoa (r = .631, p < .01), normal apical ridge (r = .459, p < .01), motility (r = .434, p < .01), mature spermatozoa with low residual histones (r = .364, p < .01), high plasma membrane integrity (r = .316, p < .01) and nonfragmented DNA levels (r = .236, p < .05). It was negatively correlated with spermatozoa having reacted acrosome (r = −.654, p < .01). A fertility model built using a combination of sperm HBA and either sperm livability or viability predicts, respectively, 86.1% (r2 = .861, p < .01) and 85.9% (r2 = .859, p < .01) variability in buffalo bull fertility. In conclusion, sperm HBA may prove to be a single robust predictor of Nili-Ravi buffalo bull fertility.  相似文献   
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Genetic Variations in Bone Density, Histomorphometry, and Strength in Mice   总被引:6,自引:0,他引:6  
The purpose of this study was to assess breed-related differences in bone histomorphometry, bone biomechanics, and serum biochemistry in three mouse breeds shown to differ in bone mineral density (BMD) (as measured by DXA) and bone mineral content (BMC). Femurs, tibiae, and sera were collected from 16-week-old C3H/HeJ {C3H}, C57BL/6J {BL6}, and DBA/2J {DBA}mice (n = 12/breed). Data collected included BMC and BMD (femora), histomorphometry of cancellous (distal femur) and cortical bone (diaphyseal tibiae and femora), bone strength (femora), and serum alkaline phosphatase (ALP). Consistent with previous reports, BMC and BMD were higher in C3H than in BL6 or DBA mice. The higher BMD in the C3H breed was associated with greater cancellous bone volume, cortical bone area, periosteal bone formation rate, biomechanical strength, and serum ALP. However, mid-diaphyseal total femoral and tibial cross-sectional area and moment of inertia were greatest in BL6, intermediate in C3H, and lowest in DBA mice. The specific distribution of cortical bone in C3H, BL6, DBA mice represents a difference in adaptive response to similar mechanical loads in these breeds. This difference in adaptive response may be intrinsic to the adaptive mechanism, or may be intrinsic to the bone tissue material properties. In either case, the bone-adaptive response to ordinary mechanical loads in the BL6 mice yields bones of lower mechanical efficiency (less stiffness per unit mass of bone tissue) and does not adapt as well as that of the C3H mice where the final product is a bone with greater resistance to bending under load. We suggest that the size, shape, and BMD of the bone are a result of breed-specific genetically regulated cellular mechanisms. Compared with the C3H mice, the lower BMD in BL6 mice is associated with long bones that are weaker because the larger cross-sectional area fails to compensate completely for their lower BMD and BMC. Received: 16 November 1999 / Accepted: 19 April 2000 / Online publication: 27 July 2000  相似文献   
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Limited research in young adults and immature animals suggests a detrimental effect of tobacco on bone during growth. This study investigated the effects of nicotine, the major alkaloid component of tobacco, on calciotropic hormone concentrations and bone status in growing female rats. One-month-old animals received either saline (n = 10), nicotine at 3.0 mg/kg/day (n = 10), or nicotine at 4.5 mg/kg/day (n = 10) administered subcutaneously via osmotic minipumps for either 2 or 3 months. Sera, femora, tibiae, and lumbar vertebrae (3–5) were collected at necropsy. The concentrations of serum calcium, phosphorus, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, parathyroid hormone, calcitonin, and insulin-like growth factor-I were determined. Bone variables evaluated included mineral content and density (vertebrae and femora), cancellous and cortical histomorphometry (tibiae), and bone strength (vertebrae and femora). Statistically significant differences in serum mineral and hormone concentrations were not associated with nicotine dose or exposure time. No significant nicotine treatment effects were detected for bone mineral content and density, bone histomorphometry, or bone strength. We conclude that nicotine treatment for 2 or 3 months at serum concentrations in the upper range of those found in smokers has no detrimental effect on bone mass, volume, or strength in the growing rat. Received: 20 May 1999 / Accepted: 21 January 2000  相似文献   
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This urban community clinic had poor asthma outcomes compared to the state of Minnesota. The standard of care supports an annual Asthma Action Plan (AAP). However, the majority of patients at this clinic had not received one. This quality improvement project aimed to improve asthma control, measured by an asthma control test of at least 20, through AAP implementation supported by all team members. The clinic’s interdisciplinary champion group implemented workflow changes via practice facilitation and Plan-Do-Study-Act cycles. Asthma control rates increased from 23% to 58% in adults and 45% to 63% in children over one year, a statistically significant change.  相似文献   
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Maternal and Child Health Journal - Breastfeeding and responsive feeding are important practices that support the health of infants and women. In the United States, breastfeeding continuation rates...  相似文献   
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Subclavian stenting can be extremely difficult in a hostile type II aortic arch (with acute angulation of the subclavian artery origin) or type III aortic arch. This case illustrates use of a low-profile system to gain through-and-through (flossing) access through the brachial artery to facilitate stenting via the femoral approach. This approach can be useful in patients with small brachial arteries where the risk of complication may be high if a standard vascular sheath was placed for stenting via the brachial approach. This technique also avoids the use of a surgical cut down.  相似文献   
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