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481.
482.
483.
The use of ionizing radiation and ethylene oxide for the sterilization of pharmaceutical base materials of animal origin, used to produce organopreparations, was studied. The materials included liver extract, pancreas extract, dried thyroid and intrinsic factor. The effective sterilizing doses for the examined materials and dependence between effective ionizing radiation dose and primary contamination were determined. 相似文献
484.
Maurice Manning Ling Ling Cheng Stoytcho Stoev Krzysztof Bankowski Jozef Przybyiski Wieslaw A. Klis Wilbur H. Sawyer Nga Ching Wo W. Y. Chan 《Journal of peptide science》1995,1(1):66-79
We have investigated the effects of mono-substitutions with the conformationally restricted amino acid, 1,2,3,4 tetrahydroisoquinoline-3-carboxylic acid (Tic) at position 3 in arginine vasopressin (AVP), at positions 2, 3 and 7 in potent non-selective cyclic AVP V2/V1a antagonists, in potent and selective cyclic and linear AVP V1a antagonists, in a potent and selective oxytocin antagonist and in a new potent linear oxytocin antagonist Phaa-D -Tyr(Me)-Ile-Val-Asn-Orn-Pro-Orn-NH2 (10). We report here the solid-phase synthesis of peptide 10 together with the following Tic-substituted peptides: 1, [Tic3]AVP; 2, d(CH2)5[D -Tic2]VAVP; 3, d(CH2)5[D -Tyr(Et)2Tic3]VAVP; 4, d(CH2)5[Tic2Ala-NH29]AVP; 5, d(CH2)5[Tyr(Me)2, Tic3, Ala-NH29]AVP; 6, d(CH2)5 [Tyr(Me)2, Tic7]AVP; 7, Phaa-D -Tyr(Me)-Phe-Gln-Asn-Lys-Tic-Arg-NH2; 8, desGly-NH2,d(CH2)5[Tic2,Thr4]OVT; 9, desGly-NH2d(CH2)5[Tyr(Me)2Thr4, Tic7]OVT; 11, Phaa-D-Tic-Ile-Val-Asn-Orn-Pro-Orn-NH2, using previously described methods. The protected precursors were synthesized by the solid-phase method, cleaved, purified and deblocked with sodium in liquid ammonia to give the free peptides 1–11 which were purified by methods previously described. Peptides 1–11 were examined for agonistic and antagonistic potency in oxytocic (in vitro, without Mg2+) and AVP antidiuretic (V2-receptor) and vasopressor (V1a-receptor) assays. Tic3 substitution in AVP led to drastic losses of V2, V1a and oxytocic agonistc activities in peptide 1.L - and D -Tic2 substitutions led to drastic losses of anti-V2/anti-V1a and anti-oxytocic potencies in peptides 2, 4, 8 and 11 (peptide 2 retained substantial anti-oxytocic potency; pA2 = 7.25 ± 0.25). Whereas Tic3 substitution in the selective V1a antagonist d(CH2)5[Tyr(Me)2, Ala-NH29]APV(C) led to a drastic reduction in anti-V1a potency (from anti-V1a pA2) 8.75 to 6.37 for peptide 5, remarkably, Tic3 substitution in the V2/V1a antagonist d(CH2)5[D -Tyr(Et)2]VAVP(B) led to full retention of anti-V2 potency and a 95% reduction in anti-V1a potency. With an anti-V2 pA2 = 7.69 ± 0.05 and anti-V1a pA2 = 6.95 ± 0.03, d(CH2)5[D -Tyr(Et)2,Tic3]VAVP exhibits a 13-fold gain in anti-V2/anti-V1a selectivity compared to (B). Tic7 substitutions are very well tolerated in peptides 6, 7 and 9 with excellent retention of the characteristic potencies of the parent peptides. The findings on the effects of Tic3 substitutions reported here may provide promising leads to the design of more selective and possibly orally active V2 antagonists for use as pharmacological tools and as therapeutic clinical agents for the treatment of the syndrome of the inappropriate secretion of antidiuretic hormone (SIADH). 相似文献
485.
486.
Esthesioneuroblastoma (olfactory neuroblastoma) is a rare malignant neoplasm derived from the olfactory epithelium. It was diagnosed by cytologic study of fine needle aspiration biopsy smears of a tumor situated in the nasopharynx in a 57-year-old man. 相似文献
487.
The main sites of lead entering the protonemata were spores with broken cell walls and apical cells of protonemata. The lead
ions could enter the symplast probably by endocytosis but we can not exclude diffusion as the way of entering. Lead deposits
inside a protoplast were observed after 2 h of lead application. After 12 h, Pb deposits were commonly present in all cell
structures surrounded by a membrane. Some disturbances in ultrastructure of organelles were found after 8 h. The most frequent
were: change of endoplasmatic reticulum configuration from linear to concentric one in many cases surrounding other organelles
(e.g. mitochondria) and large and numerous plastoglobuli in chloroplasts. Longer treatment of protonemata with lead (24 h or 48
h) caused degeneration of organelles and even death of the cell.
The present work was supported by a grant from the State Commitee for Scientific Research no. 1575 9101 for E.A.G. 相似文献
488.
M Wo?niewski 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(30-31):550-552
Technique and results of the conservative treatment of 116 female patients with secondary lymphedema of the upper extremity following total mastectomy are discussed. It was found, that intermittent pneumatic massage combined with exercises decreased mild edema by more that 50%, moderate edema by nearly 40%, and marked edema by more that 25%. Complete disappearance of edema was achieved in nearly 50% of patients with mild swelling. Improvement was seen in 20% of the treated patient independently of the extension of edema. 相似文献
489.
A Gola D Wo?owiec S Potoczek 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1991,46(37-39):697-699
The possible interaction between hematopoietic neoplasms and ischemia of the lower limbs in patients with both pathologies was subjected to analysis. Anaemia, polycythemia, thrombocythemia, increased leucocytosis in the peripheral blood, and hyperuricemia exerted unfavourable effect on the blood flow through the arteries of the lower limbs. In some cases effective cytostatic treatment diminished the ischemia of the lower limbs. Interactions between various drugs used in the chronic treatment of both pathologies in the same patient was also examined. 相似文献
490.
Investigations were carried out to determine the sites of lead uptake within the frond and the root ofLemna minor. With the sodium rhodizonate four regions favoured in lead uptake were distinguished: the frond region between the base and
the node, the basal part of the root, and the regions at the proximal and distal ends of the root cap. For analysis in electron
microscope only the root regions were chosen. The highest rate of lead uptake was found in the basal part of the root. Lead
was present in the apoplast of this region after 5 min of exposure and was observed in the stelar cells after 30 min of incubation.
Lead deposits were detected mostly in the cell walls adjacent to the plasma membrane and in the lumen of several endomembrane
compartments - the endoplasmic reticulum (ER), dictyosomal vesicles, nuclear envelope and the vacuoles. Lead induced changes
of cell ultrastructure; an increase in the number of membraneous structures, swelling of ER cisternae and distortion of the
dictyosomal cisternae were observed after 2 to 6 h of exposure.
We wish to thank Mrs. G. Winiecka for her technical assistance in preparing the photographs. 相似文献