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1.
Haemorrhagic shock was produced in anaesthetized dogs, by rapid arterial bleeding to mean arterial blood pressure 35 mmHg, and maintained oligaemic for 4 h followed by return of withdrawn blood(R0WB). Dogs were observed for 72 h after ROWB for survival and recovery, and, for histopathological (HP) studies on liver, dogs were sacrificed 2 h after ROWB in non-survival experiments. Desferrioxamine mesylate (25mg/kg) was administered intra-muscularly at 2,3 and 4h after blood loss in survival experiments and for HP studies the drug was given at 4 h in one group and at 2 h plus 4 h after blood loss in the second group. With the drug given at 3 or 4h, survival was 70% and 100% while in the 2h and the untreated groups it was 50%. Recovery was rapid in all the drug treated survivors, few became conscious within 30min. showed slight activity by 4-6 h, all were almost normally active by 24 and fully so by 72 h after ROWB. All the 5 control survivors remained unconscious/drowsy upto 24 h; 3 were sluggish at 72 h. By group analysis, serum iron elevation during the oligaemic and at the end of the post-oligaemic phase was less in the drug-treated animals. HP changes of shock in the liver studied by light microscopy, were markedly reduced in severity and were less prevalent in the drug-treated dogs. The salutory effects of desferrioxamine may be due to inhibition of iron catalyzed free-radical production and tissue damage, through its strong iron chelating action. It may have a therapeutic advantage in this emergency condition without the disadvantages of toxicity inherent in prolonged use.  相似文献   
2.
Antiserum against an N-terminal sequence of murine prohormone convertase-1 (mPC1) incorporating the sequence immediatley following the junction between the putative pro-region and the active enzyme was obtained. This was accomplished using the multiple antigenic peptide (MAP) approach whereupon an 8-branched polylysine core to which are grafted multiple copies of a 16 amino acid peptide representing the N-terminal sequence of mPC1 (positions 84–99) was synthesized by solid-phase Fmoc chemistry. The ensuing peptide was purified and fully characterized by RP-HPLC, 1H-NMR, amino acid composition, peptide sequencing and ion-spray mass spectrometry. The immunological properties of the resulting antibodies in detecting recombinant PC1 in both crude and purified preparations were compared with antibodies raised against a similar N-terminal segment of PC1 but using the conventioanl method of peptide–carrier protein conjugation and also developed against a C-terminal fusion protein of PC1. Our data indicate that the MAP antibody was as efficient as both the amino and carboxy-terminal antibodies in qualitative as well as quantitative analysis of PC1 encoded protein by radioimmunoassay. Following an identical approach, antibodies against other prohormone convertases like furin, PC5/6 and PACE4 were also developed and subsequently applied to a number of biochemical and immunological studies. In each case, the ease of preparation and high immunogenicity of the MAP approach were confirmed and reside in the simplicity and rapidity with which a potent and useful antiserum is obtained.  相似文献   
3.
During a phase I trial of interleukin-1 (IL-1) in patients with ovarian carcinomas, the effects of this treatment on blood granulocyte respiratory burst and locomotive responses were examined. Differences in baseline granulocyte function in patients as well as dose-related effects of IL-1 treatment were observed. Patients enrolled early in the trial (low-dose patients) had significantly lower locomotive responses before treatment than their paired controls; these low responses normalized after 5 days of continuous-infusion IL-1 treatment. Patients enrolled later (high-dose patients) had normal locomotive responses before treatment and IL-1 treatment was associated with suppression of responses to selected stimuli at the end of treatment. Pretreatment respiratory burst responses in both low-and high-dose patient groups were essentially normal, but the rates of granulocyte H2O2 production following phorbol myristate acetate stimulation became significantly less than control values at the end of treatment. In vitro exposure of either patient or control cells to 150 U/ml IL-1 did not alter their locomotive or respiratory burst responses, suggesting the observed in vivo effects were not mediated directly by IL-1. Treatment with IL-1 is associated with changes in ex vivo granulocyte function that are related to the IL-1 dose. Treatment with low doses of IL-1 may provide a means of normalizing abnormal polymorphonuclear leukocyte function in some patients with ovarian malignancies.  相似文献   
4.
Metabolic changes during rooting in stem cuttings of five mangrove species   总被引:3,自引:0,他引:3  
Vegetative propagation through rooting in stem cuttings in five tree mangroves namely Bruguiera parviflora, Cynometra iripa, Excoecaria agallocha, Heritiera fomes, and Thespesia populnea using IAA, IBA and NAA was reported. Spectacular increase in the root number was noted in the cuttings of H. fomes and C. iripa treated together with IBA (5000 ppm) and NAA (2500 ppm). The highest number of roots was obtained with IBA (2500 ppm) and NAA (500 ppm) in E. agallocha. B. parviflora and T. populnea responded better to IAA and IBA treatment. The species specific variation in the rooting response to exogenous application of auxins was reflected in the metabolic changes during initiation and development of roots in cuttings. Biochemical analysis showed increase of reducing sugar in the above-girdled tissues at initiation as well as subsequent development of roots which was further enhanced by the use of auxins. Decreases in the total sugar, total carbohydrate and polyphenols and increase in total nitrogen were recorded in the girdled tissues and the high C/N ratio at the initial stage helped in initiation of roots in all the species. Interaction of IBA and NAA promoted starch hydrolysis better than IAA and IBA during root development and subsequently reduced the C/N ratio and increased the protein-nitrogen activity during root development which suggest the auxin influenced mobilization of nitrogen to the rooting zone.Abbreviations IAA Indole-3-acetic acid - IBA Indole-butyric acid - NAA A-naphthalene acetic acid  相似文献   
5.
In vitro binding studies have shown that warfarin binds strongly to both ligandins (Y) and Z protein obtained from rat liver cytosol with dissociation constants of 11.7 and 10.1 μM respectively. Increasing concentrations of oleate ion significantly increased the dissociation constant of warfarin with either protein, whereas laurate ion showed the same behavior only with Z protein. On the other hand, the binding of warfarin to liver cytoplasmic proteins in vivo was decreased in 72-h-pre-fasted rats, although such fasting failed to produce any increase in the in vivo levels of the cytoplasmic free fatty acids (FFA). However, based on the results of the in vitro binding study, it is suggested that changes in the composition of hepatic cytoplasmic free fatty acids as a result of fasting could reduce the in vivo binding of warfarin to Y and Z proteins and hence could lead to an increase of unbound warfarin in liver cytosol.  相似文献   
6.
Melovinone, a new alkaloid isolated from the roots of Melochia tomentosa has been characterized as 3,7,8-trimethoxy-2-methyl-5(5′-phenylpentyl)-4-quinolinone.  相似文献   
7.
8.
The lysolecithin extraction procedure originally described by Sadleret al. (1974) has been modified to yield a H+-ATPase with high levels of Pi-ATP exchange activity (400–600 nmol × min–1 × mg–1). This activity is further enhanced (1400–1600 nmol × min–1 × mg–1) following sucrose density gradient centrifugation in the presence of asolectin. This enhancement results in part from a lipid-dependent activation and in part from removal of inactive complexes. The H+ translocating activity of the complex has been determined spectrophotometrically using binding of oxonol VI as an indicator of membrane potential. Pi-ATP exchange, ATP hydrolysis, and oxonol binding are sensitive to energy-transfer inhibitors (oligomycin, rutamycin) and/or uncouplers (DNP, FCCP).  相似文献   
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10.
Statistics in Biosciences - Inference procedure is a critical step of experimental researches to draw scientific conclusions especially in multiple testing. The false positive rate increases unless...  相似文献   
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