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1.
OBJECTIVE: To compare urine and vaginal flush samples collected by women at home with endocervical and urethral swabs obtained by general practitioners for their efficacy in the diagnosis of urogenital Chlamydia trachomatis infection. DESIGN: Multipractice comparative study. SETTING: 33 general practices and a central department of clinical microbiology in Aarhus County, Denmark. SUBJECTS: 222 women aged 18-25 years who for any reason had a gynaecological examination. INTERVENTIONS: Endocervical and urethral swabs were obtained by the women''s general practitioners. The same women when at home then collected a first void urine sample, a midstream urine sample, and a vaginal flush sample (using a vaginal pipette) and mailed them to the laboratory. MAIN OUTCOME MEASURES: C trachomatis defected by the polymerase chain reaction and the ligase chain reaction. Eight tests for C trachomatis were performed for every woman. When two of the eight yielded positive results the patient was considered infected. RESULTS: The overall prevalence of C trachomatis infection was 11.2% (23/205 women). Test sensitivities in samples obtained by general practitioners, samples obtained at home subjected to polymerase chain reaction, and samples obtained at home subjected to ligase chain reaction were 91%, 96%, and 100% respectively. The corresponding specificities were 100%, 92.9%, and 99.5%. CONCLUSIONS: The diagnostic efficacy of samples obtained by women at home and mailed to the laboratory was as good as for samples obtained by a general practitioner when using the ligase chain reaction. This may have important implications for the practicability of screening for this common, often asymptomatic, and treatable infection.  相似文献   
2.
Jill Rafuse 《CMAJ》1995,153(5):655-656
The CMA hopes the Commission of Inquity on the Blood System, chaired by Mr. Justice Horace Krever, “will restore faith in a system that is essential for the health and safety of all Canadians.” However, the cost implications any recommendations may have for the health care system must also be taken into consideration. The CMA made several recommendations in response to the commission''s interim report.  相似文献   
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The unwanted horse issue continues to be a major concern in the U.S. equine industry. Nonprofit organizations dedicated to rescuing, retraining, and rehoming unwanted horses are critical in minimizing this problem. This study utilized data collected nationwide from organizations that provide these services for thoroughbreds retired from racing to identify individual horse characteristics that influenced length of stay at the adoption facility as well as characteristics that increased the probability that an adopted horse would be returned to the facility. The results suggested that horses with fewer activity limitations were rehomed more quickly (p < .01), as were gray horses (relative to bays, p < .03) and stallions (relative to geldings, p < .04). Older horses took longer to rehome (p < .05). Interestingly, the results also suggested that gray horses were more likely to be returned to the facility postadoption (p < .02). Results from this study could benefit thoroughbreds retired from racing, nonprofit organizations, end consumers, and the thoroughbred racing industry.  相似文献   
5.
We present a fast, reliable and inexpensive restriction-free cloning method for seamless DNA insertion into any plasmid without sequence limitation. Exponential megapriming PCR (EMP) cloning requires two consecutive PCR steps and can be carried out in one day. We show that EMP cloning has a higher efficiency than restriction-free (RF) cloning, especially for long inserts above 2.5 kb. EMP further enables simultaneous cloning of multiple inserts.  相似文献   
6.
Sexual selection has driven the evolution and elaboration of a wide variety of displays and ornaments in male nonhuman primates, including capes, cheek flanges, and sexual coloration. Among the most sexually dimorphic of all primates is the drill (Mandrillus leucophaeus), the males of which can be 3 times the mass of females, possess large canines, and exhibit extremely bright sexual skin coloration. However, the function of male coloration in this species has never been examined. Here, we present data on male color (measured objectively using digital photography), dominance rank, measures of male-female association, and key sexual behaviors, of adult male drills (n = 17) living in four semi free-ranging enclosures at the Drill Rehabilitation and Breeding Center in Nigeria. We test the hypothesis that male coloration is a badge of status, indicating dominance rank, and the hypothesis that male coloration attracts females. We found that male coloration did indicate rank, and that high ranking, strongly colored males were more likely to associate with adult females, and more specifically with fully tumescent females. These males also engaged in more sexual activity. However, measures of male-female association and sexual behaviors were not related to male color once rank had been taken into consideration; i.e., for males of a given rank, females did not prefer those that were more colorful. We discuss the results in light of what is known about the wild drill social system, in which unfamiliar individuals may come together in “supergroups,” and in which quality indicators of competitive ability may be particularly important.  相似文献   
7.
Alzheimer’s disease (AD) is a devastating neurodegenerative condition with no known cure. While current therapies target late-stage amyloid formation and cholinergic tone, to date, these strategies have proven ineffective at preventing disease progression. The reasons for this may be varied, and could reflect late intervention, or, that earlier pathogenic mechanisms have been overlooked and permitted to accelerate the disease process. One such example would include synaptic pathology, the disease component strongly associated with cognitive impairment. Dysregulated Ca2+ homeostasis may be one of the critical factors driving synaptic dysfunction. One of the earliest pathophysiological indicators in mutant presenilin (PS) AD mice is increased intracellular Ca2+ signaling, predominantly through the ER-localized inositol triphosphate (IP3) and ryanodine receptors (RyR). In particular, the RyR-mediated Ca2+ upregulation within synaptic compartments is associated with altered synaptic homeostasis and network depression at early (presymptomatic) AD stages. Here, we offer an alternative approach to AD therapeutics by stabilizing early pathogenic mechanisms associated with synaptic abnormalities. We targeted the RyR as a means to prevent disease progression, and sub-chronically treated AD mouse models (4-weeks) with a novel formulation of the RyR inhibitor, dantrolene. Using 2-photon Ca2+ imaging and patch clamp recordings, we demonstrate that dantrolene treatment fully normalizes ER Ca2+ signaling within somatic and dendritic compartments in early and later-stage AD mice in hippocampal slices. Additionally, the elevated RyR2 levels in AD mice are restored to control levels with dantrolene treatment, as are synaptic transmission and synaptic plasticity. Aβ deposition within the cortex and hippocampus is also reduced in dantrolene-treated AD mice. In this study, we highlight the pivotal role of Ca2+ aberrations in AD, and propose a novel strategy to preserve synaptic function, and thereby cognitive function, in early AD patients.  相似文献   
8.
Connective tissues are responsive to mechanical forces. In orthodontic tooth movement it appears that the periodontal ligament (PDL) is the source of a pleuropotential cell population and extracellular matrix structure which translates mechanical perturbation information into a host of cellular events. These include proliferation, repair, differentiation, and shape change. We have designed, built, and tested a simple, adaptable machine which enables us to examine molecular changes or events in the cell nucleus, cell membrane, and the cytoskeleton of any eukasytic cell that will adhere to a membrane. These responses to clinically simulated forces applied to an in vitro system can be measured.  相似文献   
9.
Invasion of eukaryotic target cells by pathogenic bacteria requires extensive remodelling of the membrane and actin cytoskeleton. Here we show that the remodelling process is regulated by the ubiquitin C‐terminal hydrolase UCH‐L1 that promotes the invasion of epithelial cells by Listeria monocytogenes and Salmonella enterica. Knockdown of UCH‐L1 reduced the uptake of both bacteria, while expression of the catalytically active enzyme promoted efficient internalization in the UCH‐L1‐negative HeLa cell line. The entry of L. monocytogenes involves binding to the receptor tyrosine kinase Met, which leads to receptor phosphorylation and ubiquitination. UCH‐L1 controls the early membrane‐associated events of this triggering cascade since knockdown was associated with altered phosphorylation of the c‐cbl docking site on Tyr1003, reduced ubiquitination of the receptor and altered activation of downstream ERK1/2‐ and AKT‐dependent signalling in response to the natural ligand Hepatocyte Growth Factor (HGF). The regulation of cytoskeleton dynamics was further confirmed by the induction of actin stress fibres in HeLa expressing the active enzyme but not the catalytic mutant UCH‐L1C90S. These findings highlight a previously unrecognized involvement of the ubiquitin cycle in bacterial entry. UCH‐L1 is highly expressed in malignant cells that may therefore be particularly susceptible to invasion by bacteria‐based drug delivery systems.  相似文献   
10.
Age is the greatest risk factor for Parkinson''s disease (PD) which causes progressive loss of dopamine (DA) neurons, with males at greater risk than females. Intriguingly, some DA neurons are more resilient to degeneration than others. Increasing evidence suggests that vesicular glutamate transporter (VGLUT) expression in DA neurons plays a role in this selective vulnerability. We investigated the role of DA neuron VGLUT in sex‐ and age‐related differences in DA neuron vulnerability using the genetically tractable Drosophila model. We found sex differences in age‐related DA neurodegeneration and its associated locomotor behavior, where males exhibit significantly greater decreases in both DA neuron number and locomotion during aging compared with females. We discovered that dynamic changes in DA neuron VGLUT expression mediate these age‐ and sex‐related differences, as a potential compensatory mechanism for diminished DA neurotransmission during aging. Importantly, female Drosophila possess higher levels of VGLUT expression in DA neurons compared with males, and this finding is conserved across flies, rodents, and humans. Moreover, we showed that diminishing VGLUT expression in DA neurons eliminates females'' greater resilience to DA neuron loss across aging. This offers a new mechanism for sex differences in selective DA neuron vulnerability to age‐related DA neurodegeneration. Finally, in mice, we showed that the ability of DA neurons to achieve optimal control over VGLUT expression is essential for DA neuron survival. These findings lay the groundwork for the manipulation of DA neuron VGLUT expression as a novel therapeutic strategy to boost DA neuron resilience to age‐ and PD‐related neurodegeneration.  相似文献   
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