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41.
Ion-sensitive endogenous regulators of Na+,K+-ATPase obtained from epithelium of rat small intestine
From epithelial layer of rat intestinal were selected water soluble substances which influenced on Na+,K(+)-ATPase activity in 2 different ways: substances with molecular weight 220 Da, 400 Da were its activators, substance with weight 150 Da-inhibitor. Na+,K(+)-ATPase activators preincubated previously with Na+ acquire properties of inhibitors. Bivalent cations Ca, Mg remove this effect of Na-ions. 相似文献
42.
HD Petersen M Larsen M Mannstaedt GL Skytt OM Vedel JH Wandall 《Canadian Metallurgical Quarterly》1998,160(29):4302-4306
Physicians for Human Rights/Denmark visited Kashmir three times in 1993 and 1994. In Indian-held Kashmir we examined victims of torture and gunshots and we assessed similar evidence collected by local lawyers and doctors. In refugee camps for Indian Kashmiries we examined ten children, who were reported to have been tortured at the age of 5-14 years, and ten other children who allegedly had been ill-treated. Furthermore, 17 adults, who reported that they had been tortured, were examined. In nearly all cases there were physical findings in accordance with the histories of torture. In many cases, including those of the children, the findings were highly remarkable by their shape and localization. We interpret them as evidence of intentionally inflicted injuries. In the refugee camps we carried out a prevalence study of exposure to organized violence. Approximately 95% of all families had been exposed to violence; 35% reported that their children had been ill-treated. The physical findings indicate that intentional traumatization of civilians including children in Indian-held Kashmir takes place; the results of the prevalence study suggest that exposure to violence is widespread. 相似文献
43.
Kaposi's sarcoma (KS) is a malignancy suspected of having an infectious etiology. Unique viral DNA sequences were recognized in KS lesions, using a novel technique that identifies small differences between two complex genomes. The virus had homology with the herpesvirus family, especially Epstein Barr virus (EBV), yet it was distinct from the known herpesviridae, and was appropriately named human herpesvirus 8 (HHV-8) or Kaposi's sarcoma-associated herpesvirus (KSHV). HHV-8 DNA sequences were present in AIDS-associated KS, classic KS, African endemic KS, Mediterranean KS, iatrogenic KS, and KS in homosexual men without HIV infection. HHV-8 DNA sequences were also present in peripheral blood mononuclear cells (PBMC) of KS+ patients; body-cavity-based lymphomas in HIV positive patients without KS; and in tissue from a number of malignant and non-malignant lesions in patients without HIV infection. The role of HHV-8 in KS and other malignancies is not known. Viruses are notoriously trophic for lesional tissue. Therefore, in order to determine the role of HHV-8 in KS pathogenesis, HHV-8 needs to be isolated and shown to induce immortalization in a suitable system. Regardless of its role in KS, another human herpesvirus has been discovered, and the extent of its pathogenicity needs to be uncovered. 相似文献
44.
VI Lazarenko RI Shatilova GN Goncharova OM Novikov VV Solov'ev GM Sychev IP Artiukhov PG Il'inykh LA Barkhatova VV Ivanov 《Canadian Metallurgical Quarterly》1995,111(3):30-31
The authors present their experience gained in the training of ophthalmologists at the Chair of Ocular Diseases of the Krasnoyarsk Medical Institute. In 1991 the interns, instead of traditional state examinations, maintained their diploma research, which was assessed as their skills and knowledge in the field of ocular diseases, social hygiene, and public health organization. The authors prove that such diploma research is an integral part of undergraduate training and one of the types of individual work at higher educational institutions, and enumerate the topics of diploma research. 相似文献
45.
46.
EM Shulman-Roskes DA Noe MP Gamcsik AL Marlow J Hilton FH Hausheer OM Colvin SM Ludeman 《Canadian Metallurgical Quarterly》1998,41(4):515-529
NMR (1H and 31P) and HPLC techniques were used to study the partitioning of phosphoramide mustard (PM) and its aziridinium ions among alkylation and P-N bond hydrolysis reactions as a function of the concentration and strength of added nucleophiles at 37 degrees C and pH 7.4. With water as the nucleophile, bisalkylation accounted for only 10-13% of the product distribution given by PM. The remainder of the products resulted from P-N bond hydrolysis reactions. With 50 mM thiosulfate or 55-110 mM glutathione (GSH), bisalkylation by a strong nucleophile increased to 55-76%. The rest of the PM was lost to either HOH alkylation or P-N bond hydrolysis reactions. Strong experimental and theoretical evidence was obtained to support the hypothesis that the P-N bond scission observed at neutral pH does not occur in the parent PM to produce nornitrogen mustard; rather it is an aziridinium ion derived from PM which undergoes P-N bond hydrolysis to give chloroethylaziridine. In every buffer studied (bis-Tris, lutidine, triethanolamine, and Tris), the decomposition of PM (with and without GSH) gave rise to 31P NMR signals which could not be attributed to products of HOH or GSH alkylation or P-N bond hydrolysis. The intensities of these unidentified signals were dependent on the concentration of buffer. 相似文献
47.
We report the occurrence of a relapsing, severe predominantly motor neuropathy in a 75-year-old man with an IGM-K M-protein binding to gangliosides GM2, GM3, GM4, GD1a, GT1b and LM1. Motor nerve conduction velocities were slowed with conduction block. A superficial peroneal nerve biopsy specimen revealed segmental demyelination and remyelination. The patient improved after repeated plasma exchanges, and the antibody titer decreased in association with clinical recovery. This IgM M-protein has a unique, previously unreported binding specificity for terminal NeuAcalpha2-3Galbeta- moiety in common to all gangliosides bound by the antibody except GM2. M-proteins with this affinity may be involved in the pathogenesis of this and other cases of motor-dominant demyelinating neuropathy. 相似文献
48.
49.
Specimens of femoral heads were studied at necropsy in two cases of Legg-Calve-Perthes' disease. One was that of a boy aged four years ten months who died from appendicitis; the other was from a boy aged six years who died from a malignant glioma. Both had been treated for one and a half years for Legg-Calve-Perthes' disease which was in a stage of repair at the time of death. The diseased femoral heads were moderately flattened but the surface cartilage was intact. Epiphysial bone and bone marrow were partly replaced by cartilage, fibrous tissue and granulation tissue, and new bone was being formed. Inflammatory reaction was inconspicuous. Enchondral bone formation was only slightly decreased, and the structure of the growth plate was undisturbed. There was no sign of systemic bone disease. In the first case the changes indicated that more than one episode of ischaemia had occurred, and an occlusion--probably from an old thrombus--was demonstrated in the posterior inferior retinacular artery of the femoral head. The last episode of ischaemia, furthermore, had caused infarction of part of the metaphysial bone. In both cases, the central area of the metaphysial bone of the affected femur contained fat, but there were few haemopoietic cells and it therefore looked pale. The findings are discussed in relation to previous work on the pathology in Legg-Calve-Perthes' disease, recent information on the vascularisation of the femoral head in children, and experimental and comparative animal studies. 相似文献
50.
OM B?stman 《Canadian Metallurgical Quarterly》1993,18(7):851-854
The immediate preoperative body mass index and standing body height of 1128 patients who underwent surgery for lumbar intervertebral disc herniation were compared in a cross-sectional study with the corresponding values obtained from a general population sample. The material was divided into sex- and age-specific subgroups. To delineate possible differences, the 99% confidence intervals for the anthropometric mean values were constructed instead of hypothesis testing. With the exception of the oldest age group, from 50 to 59 years, the patients who underwent surgery for a disc herniation were more obese and taller than the population on average in all other sex- and age-specific subgroups. The major contrast emerged in women aged 20-29 years, in whom the 99% confidence interval for the mean body mass index of the patients undergoing surgery on was 25.1-27.3 kg/m2 versus 22.3-23.1 kg/m2 in the general population. In patients aged 20-39 years the mean body mass index was increased also when the body height of the patients was less than the mean value of the general population samples. Both an increased body mass index and a tall stature seem to have a clear association with those severe lumbar intervertebral disc herniations that require operative treatment. 相似文献