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61.
We have previously demonstrated that p100H mutant mice, which lack a functional Sox6 gene, exhibit skeletal and cardiac muscle degeneration and develop cardiac conduction abnormalities soon after birth. To understand the role of Sox6 in skeletal muscle development, we identified muscle-specific genes differentially expressed between wild-type and p100H mutant skeletal muscles and investigated their temporal expression in the mutant muscle. We found that, in the mutant skeletal muscle, slow fiber and cardiac isoform genes are expressed at significantly higher levels, whereas fast fiber isoform genes are expressed at significantly lower levels than wild-type. Onset of this aberrant fiber type-specific gene expression in the mutant coincides with the beginning of the secondary myotube formation, at embryonic day 15-16 in mice. Together with our earlier report, demonstrating early postnatal muscle defects in the Sox6 null-p100H mutant, the present results suggest that Sox6 likely plays an important role in muscle development.  相似文献   
62.
63.
This study compares the ability of three commercial overnight methods, API 20E, Minitek and Enteric-Tek, to accurately and completely identify 368 clinically isolatedEnterobacteriaceae without supplemental tests. Organisms includedEscherichia coli (54 strains),Shigella spp. (7),Edwardsiella tarda (1),Salmonella enteritidis (10),Citrobacter spp. (30),Klebsiella spp. (55),Enterobacter spp. (68),Hafnia alvei (2),Serratia spp. (33),Proteus spp. (64),Morganella morganii (24),Providencia spp. (18), andYersinia enterocolitica (2). Methods were those of the manufactures without supplemental tests. API 20E correctly identified 93.2 % of strains to species and 3.3 % to genus level only, with 3.0 % as part of a spectrum of identifications, and 0.5 % incorrect identifications. Minitek yielded 96.0 % correct identifications to species and 0.5 % to genus level only, with 2.5 % spectrum identifications, and 1.0 % incorrect identifications. Enteric-Tek correctly identified 97.0 % of strains to species level with 3.0 % spectrum identifications. API 20E identification of someSerratia andCitrobacter strains was to genus level only. Problem organisms for Minitek includedEnterobacter agglomerans andSerratia marcescens. A comparison of these three commercial methods shows that all three have the ability to identify most clinically isolatedEnterobacteriaceae without supplemental tests.  相似文献   
64.
Four commercial kits - Oxi/Ferm (OF), API 20E (AP), Minitek (MT), Flow N/F (NF) were evaluated, without additional tests, for identification of 105 opportunistic Gram-negative non-fermentative rods. OF correctly identified 42% of strains, with 35% as part (but not first) of a spectrum of identifications (SI) and 23% incorrect identification. MT yielded 75% correct identification, with 12% SI and 13% incorrect. AP correctly identified 64% of strains, with 26% SI, 10% incorrect. NF correctly speciated 70% of strains, with 24% SI, 6% incorrect. All 4 methods show deficiencies in identification of these rare but increasingly clinically encountered organisms. Addition of new tests/modification of existing ones would render these systems more capable of identifying this organisms group.  相似文献   
65.
The isthmo-optic nuclei (ION) and ectopic neurons, which constitute the centrifugal visual system (CVS), are thought to be cholinoceptive and nitrergic. However, it is not clear which neurons express these markers, namely the ones that project to the retina rather than in neurons that only participate in a local circuit. Therefore, to characterize the neurochemical patterns of the centrifugal visual system in the post-hatched chick, retinopetal cells of the isthmo-optic nuclei and the ectopic region were identified via immunolabeling for cholera toxin, a neuronal tracer, which has been injected in the ocular globe. Then, double labeled with acetylcholinesterase histochemistry to reveal cholinergic synapses, or NADPH-diaphorase histochemistry as a nitrergic marker. Briefly, acetylcholinesterase activity was present mainly in cholera toxin labeled cell bodies of the isthmo-optic nucleus and the ectopic region indicating that retinal projecting neurons of centrifugal visual system comprise a cholinoceptive pathway. On the other hand, NADPH-diaphorase histochemistry was present in the neuropile and sparse cell bodies inside of the isthmo-optic nucleus and in ectopic neurons which were not cholera toxin positive suggesting their role in an intrinsic circuit of the centrifugal visual system. These data support the idea that these two neurochemical systems are present in distinct neuronal populations in the centrifugal visual system.  相似文献   
66.
dl-Ethylketazocine (EKC, 0.01 mg/kg) and saline were established as discriminative stimuli for food-maintained responding in macaque monkeys. Thirty consecutive presses on a right or left lever were reinforced with food, contingent on whether EKC or saline were administered before the session. For tests of antagonism, naltrexone, or UM 979 [(l)-5,9-alpha-dimethyl-2-(3-furylmethyl)-2-hydroxy-6,7-benzomorphan] was administered concomitantly with EKC,dl-cyclazocine, or nalorphine. Both antagonists blocked completely the EKC discriminative stimulus. The antagonism of the stimulus and rate-altering effects of EKC was surmountable, with considerable intersubject variability in the magnitude of the EKC dose increase required to overcome the blockade. Cyclazocine and nalophine, mixed agonist-antagonist opioids that share stimulus properties with EKC, were also susceptible to antagonism. Naltrexone antagonized completely the EKC stimulus effects of nalorphine; naltrexone and UM 979 antagonized completely the EKC stimulus effects of cyclazocine. Naltrexone antagonism of the cyclazocine stimulus was not surmountable, due to a lack of antagonism of the rate-decreasing effects of high cyclazocine doses.  相似文献   
67.
Maternal and Child Health Journal - The Maternal and Child Health (MCH) Pipeline Training Program, promotes development of a diverse health workforce by training undergraduate students from...  相似文献   
68.
Prevention Science - Screening is an essential prevention practice for a number of health conditions. However, screening coverage remains generally low. Studies that investigate determinants of...  相似文献   
69.
Maternal and Child Health Journal - Low birthweight (LBW) is a significant public health problem in sub-Saharan Africa and LBW in rural Zambia is high. Our study explored the prevalence of LBW for...  相似文献   
70.
Prevention Science - The NAMWEZA intervention was implemented, using a ten-session group format, to build skills targeting psychosocial vulnerabilities and enhancing HIV prevention among people...  相似文献   
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