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Sudden infant death syndrome (SIDS) remains the commonest cause of death in the post-neonatal period in the developed world. A leading hypothesis is that an abnormality in the brainstem of infants who succumb to SIDS, either causes or predisposes to failure to respond appropriately to an exogenous stressor. Neuronal apoptosis can lead to loss of cardiorespiratory reflexes, compromise of the infant's ability to respond to stressors such as hypoxia, and ultimately a sleep-related death. The dorsal motor nucleus of the vagus (DMNV) is a medullary autonomic nucleus where abnormalities have regularly been identified in SIDS research. This review collates neurochemical findings documented over the last 30 years, including data from our laboratory focusing on neuronal apoptosis and the DMNV, and provides potential therapeutic interventions targeting neurotransmitters, growth factors and/or genes.  相似文献   
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Neonatal male circumcision (NMC) is being scaled up in Zambia and elsewhere in Southern Africa as a long-term HIV prevention strategy. We conducted 12 focus group discussions with 129 parents and grandparents in Lusaka, recruited from two sites providing free NMC services and information about NMC, to explore the acceptability of circumcising newborn boys. Most participants recognized the benefits of circumcision for HIV prevention, and the advantages of circumcising their children and grandchildren at a young age. Fear of negative outcomes, concerns about pain, and issues around cultural identity may challenge NMC uptake. To effectively promote the service, the upper age limit for NMC must be emphasized, and fathers must be targeted by messaging campaigns.  相似文献   
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Multidentate, soft-Lewis basic, complexant scaffolds have displayed significant potential in the discrete speciation of the minor actinides from the neutron-absorbing lanthanides resident in spent nuclear fuel. Efforts to devise convergent synthetic strategies to targets of interest to improve liquid–liquid separation outcomes continue, but significant challenges to improve solubility in process-relevant diluents to effectively define meaningful structure–activity relationships remain. In the current work, a synthetic method to achieve the challenging 2,2′-bipyridine bond of the bis-1,2,4-triazinyl-2,2′-bipyridine (BTBP) complexant class leveraging a Pd-catalyzed Ullman-type coupling is reported. This convergent strategy improves upon earlier work focused on linear synthetic access to the BTBP complexant moiety. Method optimization, relevant substrate scope and application, as well as a preliminary mechanistic interrogation are reported herein.

Access to functionalized BTBP complexants through a reductive coupling strategy decreases linearity of common synthetic strategies towards these relevant materials for separations.  相似文献   
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Abstract

The incidence and pathological features of colorectal carcinoma in a population of veterans disabled by myelopathy were examined by record review.

Thirteen cases of colorectal carcinoma were found among the 1023 such individuals (99 percent male) who were hospitalized and subsequently followed between April 1, 1973 and September 22, 1983. The age adjusted incidence rates ranged from 316 per 100,000 person years in the sixth decade to 1886 per 100,000 person years in the ninth decade of age. These rates were two to six times the highest reported rates for general male populations (P < 0.05).

The location of carcinoma was proximal to the rectosigmoid colon in 62 percent of the 13 paralyzed patients, but in only 12 percent of 31 nonparalyzed male patients With colorectal carcinoma diagnosed at the same hospital in 1977-1979 (P < 0.001). The stage of the tumor at diagnosis was Dukes Kirklin C in 83 percent of paralyzed patients and 48 percent of the non paralyzed patients (P < 0.001).  相似文献   
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