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31.
Reda M. El-S. Hassanine Mohammed O. Al-Jahdali 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(3):289-295
During June and July of 2007, a total of 130 specimens of the fish Rastrelliger kanagurta Cuvier (Teleostei, Scombridae), ranging between 19–31 cm in total length, were caught in the Red Sea off the coast of Sharm
El-Sheikh, South Sinai, Egypt, and examined for infections by acanthocephalans (65 fish/month). Of this number, 29 (22.30%)
were slightly or heavily parasitized by the acanthocephalan Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 (Cavisomidae); no other helminth parasites were found in the intestine of R. kanagurta. Twenty-nine infrapopulations of D. nudus, ranging from 23–218 individuals were collected from the infected fishes. These infrapopulations were distributed in a well-defined
fundamental niche along the intestine of R. kanagurta, where the distribution of male worms was not random with respect to female worms size and position and suggests that the
male-male competition for access to female may be intense and may select for large males. No correlation between fish size
and infrapopulation size was observed. Correlations between female-to-male sex ratio and infrapopulation size, numbers of
females and their mean lengths, numbers of males and their mean lengths, mean female length and mean male length within infrapopulation
were very strong, and clearly suggest that as the infrapopulation size increased, the number of females and their mean lengths
decreased and the number of males and their mean lengths increased. Combination of these results strongly suggests density-dependent
effects and competition between male worms. The relationship between the mean female length or size and the number of eggs
within its pseudocoel was strongly positive; egg production by female worm significantly decreases as the infrapopulation
size increases, suggesting density-dependent reduction in female worm fecundity. Tendency for the variability in male testes
size was not significant in infrapopulations of D. nudus. All of these results are discussed. 相似文献
32.
本文道报27例同种异体骨移植兔的红细胞免疫功能指标检测结果。红细胞C_3b受体花环率变化,以异体骨花环率最高,液氮骨其次,AAA骨花环率形成率则在正常对照值范围内变化。结果提示异体骨移植能引起明显的免疫反应,液氮骨可有一定的抗原性,能引起免疫反应,冻干骨免疫反应较低下,而AAA骨则不引起免疫反应。本文对同种异体骨移植后的红细胞免疫功能变化的机理与临床意义进行了讨论。 相似文献
33.
34.
H. Ochiai N. Hishiyama K. Higa K. Koyama M. Seita H. Fujise 《Comparative clinical pathology》2007,16(1):61-63
The cation transport and regulatory volume decrease (RVD) were investigated in the red blood cells (RBCs) of northern fur
seals (Callorhinus ursinus). Extracellular Ca-dependent Na efflux was increased to threefold by hypotonicity. K–Cl cotransport activity was not detected
by hypotonic medium, but measured only by nitrite or N-ethylmaleimide stimulation. RBCs were restored to their original volume after being swollen in hypoosmotic medium with Ca,
though this recovery was inhibited by the addition of quinidine. Based on these results, Na/Ca exchange transporter played
the major role in the regulatory volume decrease in the RBCs of northern fur seals.
H. Fujise has passed away. 相似文献
35.
作者对抗体包被的红为性进行研究,发现抗体包被改变了红细胞的变形性,在我们研究的抗体量范围内,抗体量越多,红细胞的变形性越小,作者从血液流变学的角度对上述结果作了讨论,并提出了通过测定其对红细胞变形性的影响来比较准确地标定抗体效价的可能性。 相似文献
36.
Dr. Robert Law 《Pflügers Archiv : European journal of physiology》1972,334(4):303-309
Summary The intrarenal volumes of distribution of125I-polyvinyl pyrrolidone and51Cr-labelled red cells have been examined in rabbits under conditions of severe hydropenia and starvation-induced polyuria, and in rabbits under control conditions. The PVP space was significantly reduced, and the ratio [red cell space]:[red cell space + PVP space] significantly elevated, in the outer cortex of kidneys of hydropenic rabbits, and in the papilla of polyuric rabbits. It is suggested that the former may in some manner result from a reduction in the total cortical vascular space, whereas the latter reflects variations of medullary and appillary interstitial tonicity under these conditions. 相似文献
37.
D. Braasch 《Pflügers Archiv : European journal of physiology》1980,383(3):229-232
The influence of varying shear forces (4–10 N·cm–2) generated by a pulsating flow of 4 cycles/min, on the longitudinal electrical resistance (R) of a blood perfused small glass capillary (I.D.=0.12 mm,l=30 mm) was determined. Red cells were stiffened by stepwise addition of bile or by sterile incubation during 24–48 h. The shear dependent changes in R were closely related to red cell flexibility and apparent blood viscosity. In normal defibrinized blood Rdecreased by about 3%, while more rigid cells evoked a shear dependentincrease in R of 1–5%. The measurements performed demonstrate that the typical shapes of the electrical signals provide more information of rheological significance of red blood cell flexibility than the results of viscosity determination alone. 相似文献
38.
Summary Plastid DNA (ptDNA) from the unicellular red alga Cyanidium caldarium was isolated. A 5.8 kb Eco RI, fragment containing the entire psbA-gene was cloned and the nucleotide sequence of the psbA-gene determined. At the carboxyl terminus the encoded protein (D1) contains the seven amino acid-insertion which was found to be typical of the cyanobacteria and the cyanelles of Cyanophora paradoxa. However, the overall sequence homology does not support a direct relationship between the plastids of Cyanidium, cyanelles and the cyanobacteria. As in other photosynthetic organisms the psbA-gene is transcribed as a monocistronic mRNA. The ribosomal RNA operon was located 4 kb upstream of the psbA-gene. 相似文献
39.
J. F. Dormont D. Farin A. Schmied M. Amalric 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1989,77(2):271-282
Summary The activity of 98 Red Nucleus neurons was recorded in 3 cats operantly conditioned to perform a ballistic forelimb flexion movement triggered after a brief sound in a simple Reaction Time condition, or Delayed after the same sound in the presence of a tone cue. Fifty-eight task related neurons presented changes of activity in either one or both conditions. Forty-four of them were studied quantitatively and classified in 3 categories: 1) only 16% of the units presented similar changes of firing preceding the triggered or delayed movement; 2) most units (55%) presented different changes of activity in the two conditions: in the Delayed condition, the activation occurred earlier before the movement, and/or the change in magnitude was reduced or the pattern of activity was modified; 3) moreover, for 29% of the units, the change of activity observed before movement in the Reaction Time condition was severely reduced or even absent in the Delayed condition. For some of these neurons a building-up of activity was observed very early in the Reaction Time condition, during the preparatory period, well before the occurrence of the conditioned stimulus. These results show that the Red Nucleus activity preceding a movement is clearly dependent on its initiation conditions. The distinct patterns of unit firing observed in the Reaction Time condition and in the Delayed condition are tentatively related to the different preparation and initiation constraints determined by the behavioral conditions. 相似文献
40.
基于暗视场荧光图像分析的大鼠微血管流速测量系统的建立 总被引:2,自引:0,他引:2
将荧光标记的自身红细胞注入SD大鼠体内,在荧光显微镜下观测标记红细胞在大鼠微血管中的流动情况,并通过显微摄像系统将整个过程以视频信号的形式存贮。使用视频采集卡将流速变化过程回放采样,得到暗视场下的荧光图像。然后利用帧图像分离出奇偶场的图像分析方法测定血流速度。在该系统下测量流动小室中荧光小球的流速,得到的测量值与实际值之间的误差小于7%,两者没明显的差异(P>0.05),流速测量的上限为9.6mm/s。并在大鼠微循环障碍研究中,应用此系统得到了血流速度随时间变化的情况。 相似文献