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991.
中国狂犬病毒疫苗株(5aG)糖蛋白基因在痘苗病毒中的表达及免疫效果观察 总被引:1,自引:0,他引:1
将克隆到的中国狂犬病毒疫苗株(5aG)的糖蛋白基因重组到痘苗病毒TK区,并在痘苗病毒P11启动子的控制下,构建了狂犬-痘苗重组病毒(VVaG)。经间接免疫荧光和Western免疫印染证明,重组病毒VVaG能良好地表达狂犬病毒糖蛋白,其分子量约为6600。用VVaG免疫小鼠,7d便可诱生较高的狂犬病毒中和抗体,21d达4169,并能100%保护狂犬病毒本毒株和国际标准攻击毒(CVS)的致死量攻击。 相似文献
992.
Accuracy of eosinophils and eosinophil cationic protein to predict steroid improvement in asthma 总被引:1,自引:0,他引:1
R. J. Meijer D. S. Postma H. F. Kauffman L. R. Arends G. H. Koëter H. A. M. Kerstjens 《Clinical and experimental allergy》2002,32(7):1096-1103
BACKGROUND: There is a large variability in clinical response to corticosteroid treatment in patients with asthma. Several markers of inflammation like eosinophils and eosinophil cationic protein (ECP), as well as exhaled nitric oxide (NO), are good candidates to predict clinical response. AIM: We wanted to determine whether we could actually predict a favourable response to inhaled corticosteroids in individual patients. METHODS: One hundred and twenty patients with unstable asthma were treated with either prednisolone 30 mg/day, fluticasone propionate 1000 microg/day b.i.d. or fluticasone propionate 250 microg/day b.i.d., both via Diskhaler. They were treated during 2 weeks, in a double-blind, parallel group, double dummy design. We measured eosinophils and ECP in blood and sputum, and exhaled nitric oxide as inflammatory parameters before and after 2 weeks in order to predict the changes in forced expiratory volume in 1 s (FEV1), provocative concentration of methacholine causing a 20% fall in FEV1 (PC20 Mch), and asthma quality of life (QOL). Secondly, to test whether these results were applicable in clinical practice we determined the individual prediction of corticosteroid response. RESULTS: We found that changes in FEV1, PC20 Mch and QOL with corticosteroids were predominantly predicted by their respective baseline value and to a smaller extent by eosinophils in blood or sputum. ECP, measured in blood or sputum, was certainly not better than eosinophils in predicting clinical response to corticosteroids. Smoking status was an additional predictor for change in FEV1, but not for change in PC20 Mch or QOL. Prediction of a good clinical response was poor. For instance, high sputum eosinophils (> or = 3%) correctly predicted an improvement in PC20 Mch in only 65% of the patients. CONCLUSION: Our findings show that baseline values of the clinical parameters used as outcome parameters are the major predictors of clinical response to corticosteroids. Eosinophil percentage in blood or sputum adds to this, whereas ECP provides no additional information. Correct prediction of clinical response in an individual patient, however, remains poor with our currently used clinical and inflammatory parameters. 相似文献
993.
Micropuncture studies on the filtration rate of single superficial and juxtamedullary glomeruli in the rat kidney 总被引:28,自引:0,他引:28
Summary Single nephron filtration rates of superficial and juxtamedullary nephrons were determined in high and low sodium rats. Single nephron GFR was calculated from TF/P inulin and tubular flow rate in superficial nephrons and single juxtamedullary GFR from corresponding data in long loops of Henle. In low sodium rats superficial nephron GFR was 23.5±6.4 (SD)×10–6 ml/min×g KW, juxtamedullary nephron GFR was 58.2±13.6 and total kidney GFR (C
In) was 0.94±0.16 ml/min×g KW. Using these single nephron values, total kidney GFR and a total number of 30,000 glomeruli per kidney, the number of superficial and juxtamedullary glomeruli was calculated to be 23,267 and 6,733, respectively. During high sodium diet superficial nephron GFR increased to 38.1±11.3 and single juxtamedullary GFR decreased to 16.5±6.6, total kidney GFR increasing to 1.01±0.24. Calculation again revealed the same distribution of the two nephron types. End-proximal TF/P inulin in superficial nephrons was 2.36±0.36 in low sodium and 2.31±0.28 in high sodium rats. Loops of Henle TF/P inulin and intratubular flow rate were inversely related: the highest TF/P inulin values and lowest intratubular flow rates were found in the descending limb. These data quantify the distribution of superficial and juxtamedullary nephrons on a functional basis and suggest a mechanism by which the kidney adjusts sodium excretion by altering the contribution of each nephron type to total kidney GFR.Supported by the Deutsche Forschungsgemeinschaft and the U.S. Department of the Army, through its European Research Office. 相似文献
994.
为探讨性别、孕周、身长体重指数和日龄对早期新生儿血化学指标的影响,我们对241例早期新生儿六大类常用血化学指标进行了检测和分析,现报道如下。 相似文献
995.
Niels Jrgensen Jrn Müller Aleksander Giwercman Jakob Visfeldt Henrik Mller Niels E. Skakkebk 《The Journal of pathology》1995,176(3):269-278
The origin of testicular germ cell tumours occurring during childhood is poorly understood. In adults, the classical seminomas and non-seminomas originate from carcinoma in situ of the testis, which can usually also be detected in seminiferous tubules adjacent to the tumours. In order to contribute with information regarding a possible association between carcinoma in situ and the childhood group of germ cell tumours, we investigated seminiferous tubules adjacent to 13 infantile yolk sac tumours, five infantile teratomas, and six adolescent germ cell tumours of various types, using morphological evaluation, immunohistochemical staining with markers for carcinoma in situ cells, and densitometric DNA measurement of the germ cells. We detected clear differences between the germ cell populations adjacent to adolescent and infantile germ cell tumours. The former were associated with both normal germ cells and carcinoma in situ cells. The presence of carcinoma in situ cells strongly suggested that the adolescent tumours arose from carcinoma in situ cells, like germ cell tumours occurring in adult men. Although we were in doubt in two cases, the infantile germ cell tumours were in general not associated with carcinoma in situ cells. The aetiology of infantile yolk sac tumours and teratomas may therefore be fundamentally different from that of adolescent and adult germ cell tumours. The origin of yolk sac tumours and teratomas remains to be elucidated. 相似文献
996.
Hans Werner Weizsäcker 《Pflügers Archiv : European journal of physiology》1988,412(1-2):147-154
The quasistatic passive venous elastic properties were studied in-vitro on 6 cylindrical segments of abdominal vena cava from Wistar rats. Using noncontact methods of deformation measurement, diameters and axial force of the segments were analyzed as a function of simultaneous axial stretch and internal pressure in the physiological range of 0–2.7 kPa. The elasticity of the wall tissue was investigated in terms of moduli of elasticity in the circumferential, axial and radial direction. Results show that the pressure-diameter relationship is highly nonlinear, indicating that veins are extremely compliant at lowest pressures and rather stiff beginning from some 0.7 kPa of pressure. The axial force decreases with pressure at small prestretches, increases at large, but remains constant for the in-vivo prestretch. The venous wall tissue is markedly anisotropic in the entire physiological range of deformations. 相似文献
997.
Andrew J. Carroll Robert P. Castleberry Josef T. Prchal Wayne H. Finley 《Cancer Genetics and Cytogenetics》1985,18(4):303-306
Several recent reports have described cases of acute nonlymphocytic leukemia with a unique chromosome translocation, t(6;9)(p23;q34). We have studied three additional patients who have acute nonlymphocytic leukemia and t(6;9)(p23;q34). Our findings provide additional support for the suggestion that this translocation is yet another distinct cytogenetic abnormality associated with myeloproliferative disorders. 相似文献
998.
R. S. Mirzoyan 《Bulletin of experimental biology and medicine》1979,87(5):440-442
An investigation by radioisotope, electromagnetic, and resistographic methods showed that Ornid reduces the cerebral blood flow. At the same time it completely inhibits constrictor reactions of the cerebral vessels to stimulation of sympathetic and somatic nerves. Ornid also has a protective action against experimental disturbances of the cerebral circulation of adrenergic nature.Laboratory of Pharmacology of the Nervous System, Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 5, pp. 427–429, May 1979. 相似文献
999.
M. Boulangé J. C. Cnockaert G. Lensel E. Pertuzon B. Vigreux 《European journal of applied physiology》1979,41(1):17-25
Summary The effects of long-term fatigue upon maximal force and peak rate of tension development (PRTD) (dF/dt max) are studied in man (elbow flexors), in the rat (pseudo-isolated gastrocnemius muscle) and in the frog (isolated sartorius muscle). The muscles are fatigued by voluntary anisometric anisotonic contractions against an elastic resistance in man, and by maximal tetanic contractions in the frog and the rat. In man, the excitation level of the muscle is controlled by the integrated surface EMG of the biceps brachii. In the animals, the muscles are stimulated by a neurostimulator. The PRTD and the maximal isometric force are measured during fatigue tests.In man, frog and rat, the maximal voluntary isometric torque or the maximal force and the PRTD decrease initially more or less rapidly according to the power developed during the fatigue process, and then less rapidly. The relationship between PRTD and maximal force is linear in the animals and curvilinear in man.The variations of maximal force and PRTD are discussed in relation to the level of excitation of the muscles and of the composition in different motor units types and their spatio-temporal recruitment. From a biomechanical point of view, it seems necessary to study the behavior of the series elastic component during the evolution of long term fatigue. 相似文献
1000.
Järvinen O Hietala M Aalto AM Arvio M Uutela A Aula P Kääriäinen H 《Clinical genetics》2000,58(6):447-454
Genetic carrier testing of children is usually not recommended. However, there are no data concerning long-term psychological consequences, experience, and satisfaction of those tested as well as their recall of the test results. We evaluated these items retrospectively 10–24 years after carrier testing performed in childhood. Study material comprised 25 families with aspatylglucosaminuria (AGU), an autosomal recessive disorder, with 35 healthy sibs from all parts of Finland tested for carriership during childhood between 1973 and 1987. Of these sibs, 25 participated in our study. The questionnaire comprised multiple-choice and open-ended questions. The psychosocial well-being of the study subjects measured by the RAND 36 item Health Survey 1.0 (RAND) was, in general, at least as good as that of controls, and showed no significant differences between carriers and non-carriers (p>0.154). All tested individuals were satisfied with the fact that they had been tested and stated that the decision to perform carrier testing on a child can be made by the parents. Of the 25 tested, 23 knew and understood their test result correctly at the time of our study. Most of the tested individuals (60%) stated that the best time for carrier testing would be in the childhood or in the teen years.
This study indicates that carrier testing in childhood for an autosomal recessive disorder (AGU) had caused no measurable disturbance of quality of life in adulthood, and those tested reported being satisfied. However, we do not recommend testing in childhood, as the result is not needed prior to the time for reproductive decisions. 相似文献
This study indicates that carrier testing in childhood for an autosomal recessive disorder (AGU) had caused no measurable disturbance of quality of life in adulthood, and those tested reported being satisfied. However, we do not recommend testing in childhood, as the result is not needed prior to the time for reproductive decisions. 相似文献