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101.
Seminal fluids of 197 males with complaints of involuntary infertility were examined for spermatozoal counts, morphological changes in the spermatozoa and cultured for ureaplasmas and mycoplasmas. In 12, no spermatozoa were present, 29 had a count of less than one million and 156 had more than one million spermatozoa per mL of the seminal fluid. Various morphological changes were detected in the spermatozoa in some cases. U urealyticum and M hominis were grown in 43.15% and 16.75% in comparison to control figures of 15.9% and 11.4% respectively. There was no correlation between growth of ureaplasmas and the spermatozoal count. Among the morphological changes, presence of coiled tails, presence of a fuzzy coat around the tail and microcolonies were highly specific for culture positivity (98.2, 98.2 and 97.35% respectively) but of low sensitivity (55.2%, 14.1% and 8.2% respectively).KEY WORDS: Mycoplasma, Spermatozoa, Ureaplasma  相似文献   
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New classes of CRTH2 antagonists, the pyridazine linker containing indole acetic acids, are described. The initial hit 1 had good potency but poor permeability, metabolic stability, and PK. Initial optimization led to compounds of type 2 with low oxidative metabolism but poor oral bioavailability. Poor permeability was identified as a liability for these compounds. Addition of a linker between the indole and diazine moieties afforded a series with good potency, low rates of metabolism, moderate permeability, and good oral bioavailability in rodents. 32 was identified as the development track candidate. It was potent in cell based, binding, and whole blood assays and exhibited good PK profile. It was efficacious in mouse models of contact hypersensitivity (1 mg/kg b.i.d.) and house dust (20 mg/kg q.d.) when dosed orally. In sheep asthma, administration at 1 mg/kg iv completely blocked the LAR and AHR and attenuated the EAR phase.  相似文献   
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Pediatric proximal femur dual-energy X-ray absorptiometry (DXA) scans present analytic challenges because of the lack of standard points of reference in the growing skeleton. The Iowa Bone Development Study (IBDS) developed a modified pediatric-specific proximal femur analysis protocol using Hologic software. Serial DXA measurements were obtained for 214 children at approximate ages 5, 8, 11, and 13 yr. Standard analysis procedures as described by the manufacturer (Hologic default) were compared with the IBDS protocol. The IBDS protocol yielded lower but more stable results for bone area, bone mineral content (BMC), and bone mineral density for total hip, femoral neck, trochanter, and intertrochanter as a result of more precisely controlling the regions of interest. Linear regression models with body size, age, and gender as predictors were developed to examine variation in measurements. Coefficients of determination (R2) with the IBDS protocol were greater for each time point, demonstrating that the modified protocol was better aligned with body size. Similarly, Spearman correlation coefficients between total hip and hip subregions were consistently higher for BMC and bone area with the IBDS protocol with differences more notable among younger children. The IBDS protocol provides a reproducible method for evaluating pediatric proximal femur DXA scans during growth.  相似文献   
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The objective of this study was to evaluate possible factors that could be contributing to altered bioenergetics of juvenile northern pike (Esox lucius) living in lakes receiving effluent from the Key Lake uranium mill in northern Saskatchewan, Canada. Although glycogen and triglycerides stores in liver and muscle were significantly greater in pike from exposure lakes compared to the reference, triglycerides stores of aquatic insects and spottail shiners that are prey items of juvenile pike showed no overall differences among lakes. Measures of parasitism, on the other hand, were negatively correlated with pike bioenergetics thereby reflecting a possible energetic cost of parasitism on reference lake fishes. The degree of infection, as measured by the abundance and biomass of intestinal parasites and the abundance of monogeneans on pike gills, was greatest in reference fishes and intermediate in low-exposure pike, whereas high-exposure fishes harbored no parasites.  相似文献   
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Introduction  

Most studies on quality of life of breast cancer survivors have not had adequate representation of ethnic minorities. The purpose of this study was to determine whether racial/ethnic differences in quality of life exist between white, African American, and Latina women in the early stages of survivorship.  相似文献   
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Peritoneal plasmacytomagenesis in inbred BALB/c mice affords an experimental model system for the study of the mechanism by which naturally occurring Myc (c-myc) translocations collaborate with host susceptibility factors and environmental influences in tumor development. Mouse plasmacytoma is initiated in approximately 80% of cases by a balanced chromosomal T(12;15)(Igh-Myc) translocation that results in a mode of Myc deregulation that renders the survival and outgrowth of the translocation-bearing tumor precursor exquisitely dependent upon factors provided by sustained inflammation (IL-6) and gut flora microbes. Tumor susceptibility genes of BALB/c, such as weak efficiency alleles of genes encoding p16(Ink4a) and Frap (mTOR), are also required for plasmacytoma, although the pathways linking these genes with deregulated Myc and the environment have not yet been elucidated. The findings in mouse plasmacytoma may be relevant for hematopoietic neoplasms in human beings, in which leukemia- and lymphoma-associated chromosomal translocation (LLA-CT) is much more frequent than subsequent neoplasia. Just like T(12;15)-carrying B-lymphocytes and plasma cells in mice, the malignant transformation of LLA-CT-bearing blood cells in humans may be a rare occurrence that requires several genetic and environmental cofactors to take place.  相似文献   
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