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11.
Behavioral development during the 1st 5 months of life was observed in 21 group-living mother-reared pigtailed (M. nernestrina) monkey infants. Periodic behavioral observation sessions provided monthly mean scores for 28 different behavioral items. Infants appeared to be separable on several behavioral continua, including their general level of activity and the nature of the mother-infant relationship. Individual differences were prominent, appeared early and persisted. Patterns of behavior were examined and found to be stable across time. Physiological data (heart rate, body temperature, sleep patterns EEG activity) were collected from 15 of the infants at a mean age of 23 weeks using totally implantable multichannel biotelemetry systems. Group mean values and measures of individual variability were obtained for 23 physiological variables. Physiological variables were correlated with each other and measures of concurrent behavior; the following relationships emerged:
12.
Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献
13.
Johnson JS Short AK Hutchison A Parrott NR Roberts IS 《Journal of clinical pathology》2000,53(9):720-721
Primary hyperoxaluria is a rare genetic disorder characterised by calcium oxalate nephrolithiasis and nephrocalcinosis leading to renal failure, often with extra-renal oxalate deposition (systemic oxalosis). Although ischaemic complications of crystal deposition in vessel walls are well recognised clinically, these usually take the form of peripheral limb or cutaneous ischaemia. This paper documents the first reported case of fatal intestinal infarction in a 49 year old woman with systemic oxalosis and advocates its consideration in the differential diagnosis of an acute abdomen in such patients. 相似文献
14.
Further evaluation of an in vivo teratology screen 总被引:1,自引:0,他引:1
The in vivo teratology screening procedure described previously [Chernoff N, Kavlock RJ: J Toxical Environ Health 10:541-550, 1982] was further evaluated using a total of 46 chemicals in 50 different treatment regimens. Pregnant CD-1 mice were generally treated by oral gavage on days 8-12 of gestation at a dose level predicted from a preliminary range finding study to induce a slight degree of maternal toxicity. The effects on early postnatal growth and viability were compared to results generated from standard mouse teratology bioassays as reported in the literature (there were nine regimens for which no valid comparisons could be made). The procedure correctly categorized 25 of the 30 treatment regimens which were considered developmentally toxic in the mouse, as well as nine of 11 which were considered to be nondevelopmentally toxic in the mouse. Thus, based upon the criteria used in the present study, the assay correctly classified 83% of the chemicals tested as to their effect in a standard mouse bioassay. The five nonconcurring negative findings were likely due to a combination of pharmacokinetic differences between the studies, as well as to the cessation of dosing on day 12, while critical events of organogenesis are still occurring. The assay achieves the requirements for a teratology screening system, but improved predictability would result from the addition of a lower dose level and extension of the dosing period to include later stages of organogenesis. 相似文献
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The use of ion exchange chromatography, gel filtration, and paper electrophoresis for the separation of the peptides obtained by tryptic digestion of the cowpea strain of tobacco mosaic virus protein is described. The amino acid compositions of the 13 tryptic peptides obtained were determined and accounted for 159 residues compared with the 158 found for type tobacco mosaic virus protein. The only tryptic peptide that cowpea tobacco mosaic virus protein and type tobacco mosaic virus protein have in common is asparaginyl-arginine despite the fact that the former is very similar to type tobacco mosaic virus protein in a number of its properties. The amino terminal sequence was found to be acetyl alanyl-tyrosine and the carboxyl terminal sequence was confirmed as alanine preceded by threonine. 相似文献
19.
Canfield MC; Tamarappoo BK; Moses AM; Verkman AS; Holtzman EJ 《Human molecular genetics》1997,6(11):1865-1871
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused
most often by mutations in the vasopressin V2 receptor (AVPR2). We studied
a family which included a female patient with NDI with symptoms dating from
infancy. The patient responded to large doses of desmopressin (dDAVP) which
decreased urine volume from 10 to 4 I/day. Neither the parents nor the
three sisters were polyuric. The patient was found to be a compound
heterozygote for two novel recessive point mutations in the aquaporin-2
(AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is
the site for inhibition of water permeation by mercurial compounds and is
located near to the NPA motif conserved in all aquaporins. Osmotic water
permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2
was not increased over water control, while expression of L22V cRNA
increased the Pf to approximately 60% of that for wild-type AQP2.
Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the
function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO
cells showed that the C181W mutant had an endoplasmic reticulum-like
intracellular distribution, whereas L22V and wild-type AQP2 showed endosome
and plasma membrane staining. Water permeability assays showed a high Pf in
cells expressing wild-type and L22V AQP2. This study indicates that AQP2
mutations can confer partially responsive NDI.
相似文献
20.
Russell EJ; Geremia GK; Johnson CE; Huckman MS; Ramsey RG; Washburn-Bleck J; Turner DA; Norusis M 《Radiology》1987,165(3):609-617
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes. 相似文献