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51.
摘要目的:探讨氨氯地平联合依那普利治疗原发性高血压的临床效果,观察联合用药对左心室肥厚的影响。方法:选择本院收治的原发性高血压患者92例,随机分为观察组和对照组,各46例,对照组给予苯磺酸左旋氨氯地平5mg,1次/d,口服;观察组在对照组基础上加用马来酸依那普利10mg,2次/d,口服,疗程均为24周。观察两组治疗前后血压变化,应用超声心动图测量两组左心室厚度变化。结果:治疗后,观察组总有效率为91_3%;对照组总有效率为73.9%,观察组总有效率高于对照组(P〈0.05)。治疗前两组心率、血压比较无统计学差异(P〉0.05),治疗后两组血压均明显降低,观察组收缩压、舒张压明显低于对照组(P〈O.05);观察组心率明显低于对照组(P〈0.01)。治疗前两组左心室舒张末期室间隔厚度(Leaventricularend—diastolicventricularseptalthickness,IVST)、左心室后壁厚度(1eftventricularposteriorwallthickness,U,PwT)和左室射血分数(Leftventricularejectionfxaction,LVEF)比较无统计学差异(P〉0.05);治疗后观察组IVST、L、,PwT明显低于对照组,LVEF明显高于对照组(P〈0.05)。结论:氨氯地平联合依那普利治疗原发性高血压能有效扭转左心室肥厚,降压效果较单独应用氨氯地平更佳。 相似文献
52.
Kappa-chain constant-region gene sequences in genus Rattus: coding regions are diverging more rapidly than noncoding regions 总被引:2,自引:0,他引:2
We have determined the nucleotide sequence of a 1,200-base pair (bp)
genomic fragment that includes the kappa-chain constant-region gene (C
kappa) from two species of native Australian rodents, Rattus leucopus
cooktownensis and Rattus colletti. Comparison of these sequences with each
other and with other rodent C kappa genes shows three surprising features.
First, the coding regions are diverging at a rate severalfold higher than
that of the nearby noncoding regions. Second, replacement changes within
the coding region are accumulating at a rate at least as great as that of
silent changes. Third, most of the amino acid replacements are localized in
one region of the C kappa domain--namely, the carboxy-terminal "bends" in
the alpha-carbon backbone. These three features have previously been
described from comparisons of the two allelic forms of C kappa genes in R.
norvegicus. These data imply the existence of considerable evolutionary
constraints on the noncoding regions (based on as yet undetermined
functions) or powerful positive selection to diversify a portion of the
constant-region domain (whose physiological significance is not known).
These surprising features of C kappa evolution appear to be characteristic
only of closely related C kappa genes, since comparison of rodent with
human sequences shows the expected greater conservation of coding regions,
as well as a predominance of silent nucleotide substitutions within the
coding regions.
相似文献
53.
GA Bray 《Obesity (Silver Spring, Md.)》1997,5(3):271-274
It is often difficult to identify the ‘who, when, and where’ of advances in medicine and surgery because it's a rare advance indeed (such as the use of digitalis by William Withering) that can be clearly related to the astuteness of one person at one time and place. 相似文献
54.
A Hidden Markov Model approach to variation among sites in rate of evolution 总被引:40,自引:20,他引:20
The method of Hidden Markov Models is used to allow for unequal and unknown
evolutionary rates at different sites in molecular sequences. Rates of
evolution at different sites are assumed to be drawn from a set of possible
rates, with a finite number of possibilities. The overall likelihood of
phylogeny is calculated as a sum of terms, each term being the probability
of the data given a particular assignment of rates to sites, times the
prior probability of that particular combination of rates. The
probabilities of different rate combinations are specified by a stationary
Markov chain that assigns rate categories to sites. While there will be a
very large number of possible ways of assigning rates to sites, a simple
recursive algorithm allows the contributions to the likelihood from all
possible combinations of rates to be summed, in a time proportional to the
number of different rates at a single site. Thus with three rates, the
effort involved is no greater than three times that for a single rate. This
"Hidden Markov Model" method allows for rates to differ between sites and
for correlations between the rates of neighboring sites. By summing over
all possibilities it does not require us to know the rates at individual
sites. However, it does not allow for correlation of rates at nonadjacent
sites, nor does it allow for a continuous distribution of rates over sites.
It is shown how to use the Newton-Raphson method to estimate branch lengths
of a phylogeny and to infer from a phylogeny what assignment of rates to
sites has the largest posterior probability. An example is given using
beta-hemoglobin DNA sequences in eight mammal species; the regions of high
and low evolutionary rates are inferred and also the average length of
patches of similar rates.
相似文献
55.
Three Turkish isolates of the entomopathogenic nematodes Steinernema carpocapsae, Steinernema feltiae and Heterorhabditis bacteriophora were evaluated under laboratory conditions (in different temperatures and doses) for their biocontrol efficiency against last instar Leptinotarsa decemlineata. Herein, the effects of infective juveniles in aqueous suspension against L. decemlineata were evaluated. S. feltiae appeared to be the most pathogenic nematode among the tested species. 相似文献
56.
Erhan Bozkurt Emre Atay Abdülkadir Bilir Aye Ertekin Halit Bura Koca Mehmet Cem Sabaner 《Saudi Journal of Biological Sciences》2021,28(10):5538-5546
Diabetes Mellitus (DM) is a metabolic disease characterized by hyperglycemia. Chronic hyperglycemia is associated with long-term dysfunction such as retinopathy, nephropathy, neuropathy and cardiovascular diseases. These complications increase rates of death and disability worldwide. Due to the negative effects of DM on the quality of life, the mechanism and treatments of the disease should be investigated in more detail. Most of the research in diabetes is performed in experimental animals. Experimental animal models contributed to the advancement of clinical research, the development of new therapeutic approaches, the discovery of insulin and the purification of insulin. There are many animal models of DM in the literature. But there are a few DM model studies created with chick embryos. In these studies, it was seen that there were differences in STZ doses and STZ administration techniques. The objective of this study was to create a more acceptable and easier DM model. 180 specific pathogen free (SPF) fertilized chicken eggs (White Leghorn chicken) were used in this study. STZ was administered to 160 SPF eggs for an induced DM model. The remaining 20 SPF eggs were separated as a control group. We used two different DM models (Air sack model (ASM) and Chorioallantoic membrane model (CAMM)) and blood sampling technique in our study. 160 SPF eggs were divided into two groups with 80 eggs in each group, according to the model in which STZ was administered. When the relationship between blood glucose and blood insulin levels were examined, it was determined that there was a significantly strong negative correlation in the control group and ASM 1 group; and a significantly very strong negative correlation was found in the ASM 2 group and ASM 3 group. Our data indicate that the optimal STZ dose to create a DM model was 0.45 mg/egg and the best DM model was ASM. The second technique to be the best blood sampling technique for determining blood glucose levels. We believe that ASM can be used in DM studies and anti-DM drug studies in terms of its easebly, applicability, reproducibility and low cost. 相似文献
57.
Variability in responses to thermal stress in parasitoids 总被引:1,自引:0,他引:1
GAËLLE AMICE PHILIPPE VERNON YANNICK OUTREMAN JACQUES VAN ALPHEN JOAN VAN BAAREN 《Ecological Entomology》2008,33(6):701-708
Abstract 1. To study phenotypic effects of stress, a stress is applied to cohorts of organisms with an increasing intensity. In the absence of mortality the response of traits will be a decreasing function of stress intensity because of increasing physiological costs. We call such decreasing functions type A responses. 2. However, when stress caused mortality, some studies have found that for high stress intensities, survivors performed as well as control individuals (type B responses). We proposed that type A responses are caused by the physiological cost of stress whereas type B responses are caused by a mixture of physiological costs and selection. 3. The present study exposed Aphidius picipes wasps to an increasing duration of cold storage (cold stress), and obtained variable responses as predicted when both physiological costs and selection of resistant individuals determine the outcome. 4. When cold storage of parasitoids for biological control is desirable, research should be carried out to find (i) the temperature regime and duration of storage and (ii) the least sensitive stage for storage to minimise losses from mortality and reduction of fitness of survivors. 5. Selection by cold stress as observed in the present study could result in rapid adaptation of populations exposed to such stress. 相似文献
58.
Safiye Tuncer Ayhan Kamanli Ethem AkÇil Güzin özelÇi Kavas Bülent SeÇkin Mesut Birol Atay 《Biological trace element research》1999,68(2):137-142
It has been suggested that reactive oxygen metabolites and trace elements play some role in the etiology and pathogenesis
of rheumatoid arthritis (RA). Superoxide dismutase (SOD) is believed to exert an important protective role against oxygen
toxicity. The aim of the study was to investigate the probable changes in the levels of trace elements and SOD activity in
RA. Plasma and erythrocyte copper, zinc, and magnesium levels and erythrocyte SOD activity were measured in groups of controls
and RA cases. Significantly increased erythrocyte SOD activity was found in RA patients in comparison with controls(p < 0.0001). A rise in erythrocyte Zn level(p < 0.0001) and plasma Cu level(p < 0.0001) and a decrease in erythrocyte Cu level(p < 0.05) and plasma Zn level(p < 0.05) were obtained in RA patients when compared to controls. Plasma and erythrocyte Mg levels of the RA patients showed
slight and statistically insignificant reductions when compared to controls(p > 0.05). In RA patients, there were positive correlations between erythrocyte SOD activity and Mg level (r = 0.4345,p < 0.01) and between erythrocyte Zn level and plasma Cu level(r = 0.4132,p < 0.01). There were negative correlations between erythrocyte SOD activity and plasma Zn level(r =-0.3605,p < 0.05) and between plasma Zn level and erythrocyte Cu level(r =-0.4578,p < 0.01) in RA patients.
This work was presented at the International Congress on Free Radicals in Health and Disease, 6–10 September 1995, Istanbul,
Turkey. 相似文献
59.
M Ulukanligil A Seyrek G Aslan H Ozbilge S Atay 《Memórias do Instituto Oswaldo Cruz》2001,96(7):903-909
Soil transmitted helminth (STH) infection are endemic in developing countries. A study was carried out of sewage farms, streams and vegetables to determine the sources and routes of STH infection in Sanliurfa, Turkey. Stool samples from farmhouse inhabitants as well as soil and vegetable samples from the gardens were collected and examined. In addition, water samples from streams and vegetable samples from the city market were collected and examined. One hundred and eighty-seven (59.5%) of a total of 314 samples, including 88.4% of the stool samples, 60.8% of the water samples, 84.4% of the soil samples and 14% of the vegetable samples, were found to be positive for STH eggs. These results indicate that the water, soil and vegetables are heavily contaminated, and suggest a vicious circle between humans and the environment. Improving environmental sanitation is imperative for the control of soil-transmitted helminthiasis in Sanliurfa. 相似文献
60.
van Neerven SG Bozkurt A O'Dey DM Scheffel J Boecker AH Stromps JP Dunda S Brook GA Pallua N 《Journal of brachial plexus and peripheral nerve injury》2012,7(1):5-7
ABSTRACT: Evaluation of functional and structural recovery after peripheral nerve injury is crucial to determine the therapeutic effect of a nerve repair strategy. In the present study, we examined the relationship between the structural evaluation of regeneration by means of retrograde tracing and the functional evaluation analysis of toe spreading. Two standardized rat sciatic nerve injury models were used to address this relationship. As such, animals received either a 2 cm sciatic nerve defect (neurotmesis) followed by autologous nerve transplantation (ANT animals) or a crush injury with spontaneous recovery (axonotmesis; CI animals). Functional recovery of toe spreading was observed over an observation period of 84 days. In contrast to CI animals, ANT animals did not reach pre-surgical levels of toe spreading. After the observation period, the lipophilic dye DiI was applied to label sensory and motor neurons in dorsal root ganglia (DRG; sensory neurons) and spinal cord (motor neurons), respectively. No statistical difference in motor or sensory neuron counts could be detected between ANT and CI animals. In the present study we could indicate that there was no direct relationship between functional recovery (toe spreading) measured by SSI and the number of labelled (motor and sensory) neurons evaluated by retrograde tracing. The present findings demonstrate that a multimodal approach with a variety of independent evaluation tools is essential to understand and estimate the therapeutic benefit of a nerve repair strategy. 相似文献