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141.
142.
Practical application of turbidimetrical method for the diagnosis of haemostasis disorders in babies with acute intestinal infections (AII) is described. The results of plasma biochemical analysis show that disturbances in balance between coagulation and fibrinolytic systems takes place in patients with this pathology. The correlation between biochemical parameters and clinical characteristics is observed. As follows from our data, the phase of the haemostasis disorders in babies with AII does not depend on etiology of the disease, but indicates its severity.  相似文献   
143.
Differentiating the binding properties of applied lectins should facilitate the selection of lectins for characterization of glycoreceptors on the cell surface. Based on the binding specificities studied by inhibition assays of lectin-glycan interactions, over twenty Gal and/or GalNAc specific lectins have been divided into eight groups according to their specificity for structural units (lectin determinants), which are the disaccharide as all or part of the determinants and of GalNAc alpha 1-->Ser (Thr) of the peptide chain. A scheme of codes for lectin determinants is illustrated as follows: (1) F (GalNAc alpha 1-->3GalNAc), Forssman specific disaccharide--Dolichos biflorus (DBL), Helix pomatia (HPL) and Wistaria floribunda (WFL) lectins. (2) A (GalNAc alpha 1-->3 Gal), blood group A specific disaccharide--Codium fragile subspecies tomentosoides (CFT), Soy bean (SBL), Vicia villosa-A4 (VVL-A4), and Wistaria floribunda (WFL) lectins. (3) Tn (GalNAc alpha 1-->Ser (Thr) of the protein core)--Vicia villosa B4 (VVL-B4), Salvia sclarea (SSL), Maclura pomifera (MPL), Bauhinia purpurea alba (BPL) and Artocarpus integrifolia (Jacalin, AIL). (4) T (Gal beta 1-->3GalNAc), the mucin type sugar sequences on the human erythrocyte membrane(T alpha), T antigen or the disaccharides at the terminal nonreducing end of gangliosides (T beta)--Peanut (PNA), Bauhinia purpurea alba (BPL), Maclura pomifera (MPL), Sophora japonica (SJL), Artocarpus lakoocha (Artocarpin) lectins and Abrus precatorius agglutinin (APA).(5) I and II (Gal beta 1-->3(4)GlcNAc)--the disaccharide residue at the nonreducing end of the carbohydrate chains derived from either N- or O-glycosidic linkage--Ricinus communis agglutinin (RCA1), Datura stramonium (TAL, Thorn apple), Erythrina cristagalli (ECL, Coral tree), and Geodia cydonium (GCL). (6) B (Gal alpha 1-->3Gal), human blood group B specific disaccharide--Griffonia(Banderiaea) simplicifolia B4 (GSI-B4). (7) E (Gal alpha 1-->4Gal), receptors for pathogenic E. coli agglutinin, Shiga toxin and Mistletoe toxic lectin-I (ML-I) and abrin-a.  相似文献   
144.
Thyramine, a polypeptide factor from thymus, at wide range of concentrations increased the cAMP content in rat thymocytes. Increase in the cAMP content was less distinct in spleen lymphoid cells. Thyramine decreased the cGMP content in thymocytes; minimal nucleotide level was found within 15 min of incubation. The data obtained suggest that the rate of lymphocyte maturation is important for response of the cells to the effect of immunoregulating agents.  相似文献   
145.
There are numerous physiological effects of spinal anaesthesia. This chapter focuses on the physiological effects that are of clinical relevance to the anaesthesiologist, and provides suggestions for successful management of this simple and popular technique. The mechanisms and clinical significance of spinal-anaesthesia-induced hypotension, bradycardia and cardiac arrest are reviewed. The increasing popularity of ambulatory spinal anaesthesia requires knowledge that long-acting local anaesthetics, such as bupivacaine, impair the ability to void far longer than short-acting local anaesthetics, such as lidocaine. The importance of thermoregulation during spinal anaesthesia, and the clinical consequences of spinal-anaesthesia-induced hypothermia are reviewed. Effects of spinal anaesthesia on ventilatory mechanics are also highlighted. Lastly, the sedative and minimum-alveolar-concentration-sparing effects of spinal anaesthesia are discussed to reinforce the need for the judicious use of sedation in the perioperative setting.  相似文献   
146.
To determine whether physical match between studied and tested items influences blood flow increases in the hippocampal formation associated with recognition memory, positron emission tomography (PET) was used to measure changes in regional cerebral blood flow while healthy volunteers made old/new judgements about line drawings of objects. Some objects were tested in the same size and orientation as they had appeared earlier during the study phase of the experiment; other objects were tested in a different size or orientation than when they were studied. Blood flow increases in the vicinity of the hippocampal formation were observed in the same object condition compared with the size change and the orientation change conditions, even though recognition accuracy was affected significantly only by orientation change. Results add to previous findings suggesting that physical similarity between studied items and test cues may contribute to hippocampal activation during episodic retrieval.  相似文献   
147.
为了解决耦合线滤波器谐波抑制问题,提出了一种新的结构简单的平行耦合线带通滤波器.该滤波器由平行耦合线和开路枝节组成.首先基于耦合线带通滤波器的等效电路图,通过奇偶模理论得到设计方程,并设计了带通滤波器;分析了滤波器特性与电参数之间的关系;通过仿真优化得到了滤波器的物理尺寸;制备并测试了滤波器的S参数,仿真结果和测试结果基本一致.该滤波器具有结构简单、面积小等优点,并通过引入传输零点实现了较宽的阻带抑制和较好的选择性.  相似文献   
148.
149.
This study measured volumetric liver blood flow and galactose clearance concurrently during orthotopic liver transplant in human subjects. Ultrasound transit time flowmeters measured hepatic artery and portal vein flow 1-3 h after reperfusion. Galactose (100 mg/min) was infused over 45-60 min to steady state for calculation of clearance. Mean +/- S.D. total volumetric flow was 1966 +/- 831 ml/min with portal flow contributing 86%. Mean galactose clearance was 1988 +/- 641 ml/min. There was a significant correlation (p < 0.05, r = 0.61) between volumetric total liver blood flow and galactose clearance. The data show that: (i) the newly transplanted liver is capable of metabolizing galactose within 1-3 h of reperfusion; and (ii) liver blood flow is high in the newly implanted liver. The clinical importance of this observation is that there is increased clearance of high first pass substances by the transplanted liver which may be of importance in patient management.  相似文献   
150.
Plasmodium falciparum malaria parasites were transformed with plasmids containing P. falciparum or Toxoplasma gondii dihydrofolate reductase-thymidylate synthase (dhfr-ts) coding sequences that confer resistance to pyrimethamine. Under pyrimethamine pressure, transformed parasites were obtained that maintained the transfected plasmids as unrearranged episomes for several weeks. These parasite populations were replaced after 2 to 3 months by parasites that had incorporated the transfected DNA into nuclear chromosomes. Depending upon the particular construct used for transformation, homologous integration was detected in the P. falciparum dhfr-ts locus (chromosome 4) or in hrp3 and hrp2 sequences that were used in the plasmid constructs as gene control regions (chromosomes 13 and 8, respectively). Transformation by homologous integration sets the stage for targeted gene alterations and knock-outs that will advance understanding of P. falciparum.  相似文献   
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