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101.
Several lines of experimental evidence support an association between altered Ca2+ regulation and aging. It has been supposed that free cytosolic Ca2+ concentrations ([Ca2+]i) may decrease or increase in aged animals. In this study, both resting and KCl-stimulated [Ca2+]i were measured in purified cortical synaptosomes from young (3 mo.), middle-aged (12 mo.), and old (24 mo.) Fischer 344 rats. Two additional groups of rats were included, one middle-aged and one old which were trained on a treadmill for 6 months prior to experimentation. The [Ca2+]i was determined using the fluorescent Ca2+ chelator fura-2. Net KCl-dependent changes (ΔK) in [Ca2+]i were determined by the difference between stimulatory (100 μM Ca2+/60 mM KCl) and resting (100 μM Ca2+/5 mM KCl buffer) conditions among the 3 age groups. Significant increases in [Ca2+]i were observed in each age group upon depolarization with 60 mM KCl. However, there were no significant age-dependent differences in either resting [Ca2+]i or KCl-stimulated [Ca2+]i.  相似文献   
102.
Trichophyton tonsurans infections occur in various host populations, on various body sites and with varying degrees of inflammation. This investigation was undertaken to determine whether fungal factors could explain the degree of severity in clinical symptomatology among infected children. Otherwise healthy children (n=54) presenting with tinea capitis were enrolled in this study. A thorough history was performed, the extent and severity of infection graded and a fungal specimen collected from each child. Strain type was determined by genotyping for 11 sequence variations in the rDNA and ALP1 loci. Secreted protease activity was quantitated after 5 days of growth in aqueous medium. Forty participants were evaluable. Infection duration ranged from 1 day to 3 years and clinical severity score (CSS) from 4-19. Seventeen unique fungal genotypes were present. Keratinase, collagenase and elastase activity varied 32.7-fold, 64.9-fold and 303.3-fold, respectively. A significant association was observed between genotype and disease severity with the rDNA sequence variations accounting for over 50% of the variation observed in CSS (r2=0.539; P<0.001). Phylogenetic analyses appear to suggest that the ancestral strain types of T. tonsurans cause more severe disease. These observations are consistent with reports that recently diverge anthropophilies are associated with diminished inflammatory involvement.  相似文献   
103.
Summary We investigated the heat shock response of the adenylate cyclase deficient mutant cr-1 (crisp) of Neurospora crassa. This strain was observed to be much more resistant to a lethal temperature of 50 °C than the wild type. This constitutive thermotolerance was absent in cr-1 conidiospores raised on cyclic AMP (cAMP, 2.5 mM) supplemented solid medium, but was partially restored when the conidiospores were germinated at 30 °C, a temperature which fails to induce thermotolerance in the wild-type strain. Two other crisp-like Neurospora mutants, cr-2 and cr-3 which, in contrast to cr-1, contain normal levels of cAMP, did not exhibit the thermotolerance phenomenon observed for cr-1. A cr-1, pe, fl (crisp-microconidial) strain also lacked the ability to tolerate a lethal heat treatment. Our results demonstrate that the adenylate cyclase deficient cr-1 mutant of Neu-rospora crassa expresses a constitutive thermotolerant phenotype as a consequence of its primary genetic defect: low levels of cAMP.  相似文献   
104.
Maternal and Child Health Journal - To study the relationship between cesarean Delivery (CD) and overweight in preschool children, considering the presence of birth aspects and demographic...  相似文献   
105.
As a philosophical position, pragmatism can be critiqued to distinguish truth only with methods that bring about desired results, predominantly with scientific enquiry. The article hopes to dismiss this oversimplification and propose that within mental health nursing, enquiry enlightened by pragmatism can be anchored to methods helping to tackle genuine human problems. Whilst pragmatists suggest one reality exists, fluctuating experiences and shifting beliefs about the world can inhabit within; hence, pragmatists propose reality has the potential to change. Moreover, pragmatism includes being cognisant of what works to whom reality concerns, making reality context-driven, with a view to understand how actions shape experiences so what is generated has usefulness. Hence, it somewhat follows pragmatism can inform mental health nursing, after all, nursing is a discipline of action, and awareness is needed in how actions produce experiences that patients find helpful. Given the principles of recovery are preferably adopted in mental health care, the paper will explore how pragmatism can help nurses move towards that goal; specifically, with patients voicing their experiences. This is because like pragmatism, recovery subscribes to hope that reality can progress, and through meaningful experiences and beliefs, patients have expertise about personal difficulties alongside how life may flourish, despite mental illness.  相似文献   
106.
International Urology and Nephrology - To evaluate outcomes of laparoscopic pyeloplasty (LP) in adults with poorly functioning kidney due to ureteropelvic junction obstruction (UPJO). A...  相似文献   
107.
International Urology and Nephrology - Late onset hypogonadism (LOH) is an age-dependent reduction of testosterone associated with alterations of metabolic profile, including glucose control,...  相似文献   
108.
Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The...  相似文献   
109.
Lasers in Medical Science - Photobiomodulation therapy (PBMT) has been indicated for enforcement on healing skin wounds. This study evaluated the effects of PBMT on the healing of skin wounds...  相似文献   
110.
The inner avascular zone of the meniscus has limited healing capacity as the area is poorly vascularized. Although peptide hydrogels have been reported to regenerate bone and cartilage, their effect on meniscus regeneration remains unknown. We tested whether the self‐assembling peptide hydrogel scaffold KI24RGDS stays in the meniscal lesion and facilitates meniscal repair and regeneration in an induced rabbit meniscal defect model. Full‐thickness (2.0 mm diameter) cylindrical defects were introduced into the inner avascular zones of the anterior portions of the medial menisci of rabbit knees (n = 40). Right knee defects were left empty (control group) while the left knee defects were transplanted with peptide hydrogel (KI24RGDS group). Macroscopic meniscus scores were significantly higher in the KI24RGDS group than in the control group at 2, 4, and 8 weeks after surgery. Histological examinations including quantitative and qualitative scores indicated that compared with the control group, the reparative tissue in the meniscus was significantly enhanced in the KI24RGDS group at 2, 4, 8, and 12 weeks after surgery. Immunohistochemical staining showed that the reparative tissue induced by KI24RGDS at 12 weeks postimplantation was positive for Type I and II collagen. KI24RGDS is highly biocompatible and biodegradable, with strong stiffness, and a three dimensional structure mimicking native extracellular matrix and RGDS sequences that enhance cell adhesion and proliferation. This in vivo study demonstrated that KI24RGDS remained in the meniscal lesion and facilitated the repair and regeneration in a rabbit meniscal defect model.  相似文献   
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