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61.
Kevin G Becker Insong J Lee James W Nagle Rachel D Canning Ameer M Gado Rosarelis Torres Mihael H Polymeropoulos Paul T Massa WilliamE Biddison Paul D Drew 《International journal of developmental neuroscience》1997,15(7):73
We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function. 相似文献
62.
Reduced virulence of Candida albicans mutants affected in multidrug resistance. 总被引:3,自引:0,他引:3 下载免费PDF全文
Disruption of a multidrug resistance gene (CaMDR1) in Candida albicans resulted in mutant strains that colonized mouse kidneys to very high levels but were markedly reduced in their virulence. No obvious differences in several properties related to colonization and dissemination were noted among MDR+ or mdr- strains. These results suggest that specific fungal efflux pumps play a role in fungal pathogenicity. 相似文献
63.
Claus D. Eisenbach Andreas Gldel Monika Terskan-Reinold Ulrich S. Schubert 《Macromolecular chemistry and physics.》1995,196(4):1077-1091
The synthesis and properties of segmented ABA triblock and (AB)n multiblock copolymer systems with 6,6′-disubstituted 2,2′-bipyridine (bpy) building blocks B and poly(oxytetramethylene) soft segments A are described. The access to the disubstituted bipyridines in large scale quantities was achieved by modification of conventional synthetic routes. In the presence of copper(I) ions these polymers formed mononuclear [Cu(I)(bpy)2] complexes in solution through self-assembly. The complexed copolymers were microphase separated systems in bulk with nano to mesoscopic superstructures consisting of copper-bpy complex aggregates in a polyether matrix. The thermal, mechanical and elastomer properties of the block copolymers varied with composition. 相似文献
64.
65.
J A Temlett A Ming M Saling V U Fritz A Blumenfeld T R Bilchik A L Becker P B Fourie H E Reef 《Suid-Afrikaanse tydskrif vir geneeskunde》1990,78(11):680-685
Patients with moderately severe Parkinson's disease complicated by the adverse effects of chronic levodopa use benefited from the addition of bromocriptine (Parlodel; Sandoz) in doses up to 26 mg daily, which allowed an approximate 30% reduction of levodopa dose. This resulted in a significant decrease in the amount of levodopa side-effects while maintaining or improving the original parkinsonian clinical stage. Increased effectiveness in these patients was not associated with increased dosage beyond 25-30 mg daily. When the doses of bromocriptine were increased slowly, the adverse reactions were minor and usually transient. 相似文献
66.
Effects of enteral feedback inhibition on motility,luminal flow,and absorption of nutrients in proximal gut of minipigs 总被引:2,自引:0,他引:2
Andreas Huge Eckhard Weber Prof. Dr. Hans-Jörg Ehrlein 《Digestive diseases and sciences》1995,40(5):1024-1034
We wanted to clarify whether the postprandial intestinal feedback control activated by nutrients in the distal gut exerts different effects on motility, transit of digesta, and absorption of nutrients in the proximal gut. Additionally, interrelationships among motility, transit, and absorption were to be elucidated because these relationships have only been investigated in the fasted state. In five minipigs, a 150-cm segment of the proximal jejunum was isolated by two cannulas. Motility of the jejunal segment was recorded by multiple strain gauges and analyzed by computerized methods. Markers (Cr- and Cu-EDTA) were used for the measurement of the flow rate, transit time, and absorption of nutrients. After a meal, the test segment was perfused with 2 kcal/min of an elemental diet over a period of 90 min. A feedback inhibition was activated by infusion of nutrients into the midgut at rates of 1–4 kcal/min. Saline was infused as control. With increasing energy loads infused into the midgut, the motility index and the length of contraction waves decreased, whereas the incidence of stationary contractions increased, ie, the motility changed from a propulsive to a segmenting pattern. These modulations of motility were associated with a linear decrease in the flow rate and a linear increase in transit time. Flow and transit were linearly correlated with each other. Additionally, the reduction in flow rate and the delay in luminal transit were associated with a linear increase in the absorption of nutrients. However, the increase in absorption induced by the feedback mechanism was small (7.3–13.4%) compared to the marked inhibition of the motility parameters (54–64%), the flow rate (59%), and the delay of transit (5.8-fold). Feedback control primarily modulated motor patterns and luminal flow, whereas the small increase in absorption was only a side effect due to the longer contact time of the nutrients with the mucosa.The study was supported by the Deutsche Forschungsgemeinschaft, grant Eh 64/6-3. 相似文献
67.
Ernst P. Leumann Andreas Dietl Ana Matasovic 《Pediatric nephrology (Berlin, Germany)》1990,4(5):493-497
The molar ratios of oxalate and glycolate over creatinine were determined in single urine samples of 26 infants and 27 children aged 1–5 years. In 135 children aged 5–16 years, two urine specimens were collected, one before breakfast and one at noon. Oxalate was determined by oxalate oxidase, and glycolate was measured by a colorimetric method (improved chromatotropic acid-sulphuric acid assay after prior purification by cation and anion exchanger). Both ratios (expressed in mmol/mol creatinine and analysed on a log-normal basis) were highest in infants 0–6 months old [mean oxalate 147 (95% confidence interval: 60–360), mean glycolate 175 (72–425)]. The mean oxalate ratio was 72 mmol/mol (29–174) at the age of 7–24 months, 44 (19–101) at the age of 2–5 years and 22 (12–40) in adolescents aged 16 years. Molar glycolate ratios were higher, but disclosed the same pattern. Oxalate and glycolate ratios in fasting urines did not differ significantly from those in noon samples (except glycolate in the oldest age group). Oxalate ratios correlated well with glycolate ratios in children up to 5 years of age only. Random urine samples are thus suitable for screening. However, interpretation of data requires use of age-specific reference values that are based on comparable methods. 相似文献
68.
A new method of refractive corneal surgery is presented. With the q-switched Nd:YAG-laser Visulas (Zeiss-Oberkochen) we succeed in altering the optical power of the cornea of rabbits, pigs and humans. The number of applied laser spots and the distribution pattern influence the way and the amount of change of refraction. The method, clinical and histological features, complications and prospects of the Nd: YAG laser keratorhexis are described. 相似文献
69.
70.
Abstract
Purpose:
Evaluation of the therapeutic usefulness of
the “pelvic C–clamp” (PCC) during emergency treatment
of multiply injured patients with unstable disruption
of the posterior pelvic ring.
Patients and Methods:
The data of 28 patients with
polytrauma in combination with an unstable fracture
of the posterior pelvic ring (average Injury Severity
Score [ISS]: 49 points; average Polytrauma Score [PTS]:
41 points) were retrospectively analyzed from the
moment they were admitted to the emergency room
until 48 h after admittance. The PCC was used immediately
for primary stabilization of the pelvis after
clinical diagnosis of the unstable pelvic fracture. Main
outcome measurements: development of mean blood
pressure, development of oxygenation level, period of
time until the PCC was placed, number of blood units
needed, period of time until circulatory stabilization
occurred.
Results:
The PCC was applied in all cases within an average
of 64.7 min after trauma. Seven patients (25%) died
within the first 45 min after admission. The surviving
patients showed:• an increase in mean blood pressure of 25% 20 min after
application of the PCC,• a hemodynamic stabilization 6 h after application of
the PCC,• a stabilization of the oxygenation level 6 h after application
of the PCC,• a decrease in the number of required blood units 6 h
after application of the PCC.
Conclusion:
The present study shows, that the application
of the PCC to critically injured patients with unstable
pelvic fractures leads to stabilization of the vital parameters
within a short period of time. 相似文献