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171.
A Mu?oz E Bureo JJ Ortega C Richard T Olivé MS Maldonado L Madero MA Díaz 《Canadian Metallurgical Quarterly》1998,83(11):981-984
BACKGROUND AND OBJECTIVE: To compare the estimated survival and disease-free survival between children with Ph1-positive chronic myeloid leukemia treated with allogeneic bone marrow transplantation or conventional chemotherapy. DESIGN AND METHODS: In this retrospective study we compared the results obtained in a group of 14 children who received allogeneic bone marrow transplantation (BMT) between 1983 and 1993, and another group of 27 children treated with busulfan, hydroxyurea or alpha-interferon during the same time period. Patients were transplanted at a median of 7 months from diagnosis and all except one were in their first chronic phase. Conditioning consisted in total body irradiation and cyclophosphamide in 12 cases, and busulfan was added in two. RESULTS: Of the 14 patients treated with BMT, two died of transplant-related complications and two relapsed 18 and 48 months after the BMT. Ten children remain alive and disease free at a median follow up of 60 months. The probability of DFS at 5 years is 70%. Of the 27 patients treated with chemotherapy, 22 have died at a median of 36 months from diagnosis. The probability of survival at 5 years is 5% versus 83% for the BMT group (p = 0.001). INTERPRETATION AND CONCLUSIONS: Allogeneic BMT is a safe and very effective treatment for Ph-positive CML in children. Patients who have an HLA-identical sibling donor must receive a transplant as soon as possible after being diagnosed. 相似文献
172.
H Shimizu Y Takizawa L Pulkkinen JJ Zone K Matsumoto T Saida J Uitto T Nishikawa 《Canadian Metallurgical Quarterly》1998,111(5):887-892
Most populations and some species of ticks of the genera Boophilus (5 spp.) and Rhipicephalus (ca. 75 spp.) cannot be distinguished phenotypically. Moreover, there is doubt about the validity of species in these genera. I studied the entire second internal transcribed spacer (ITS 2) rRNA of 16 populations of rhipicephaline ticks to address these problems: Boophilus microplus from Australia, Kenya, South Africa and Brazil (4 populations); Boophilus decoloratus from Kenya; Rhipicephalus appendiculatus from Kenya, Zimbabwe and Zambia (7 populations); Rhipicephalus zambesiensis from Zimbabwe (3 populations); and Rhipicephalus evertsi from Kenya. Each of the 16 populations had a unique ITS 2, but most of the nucleotide variation occurred among species and genera. ITS 2 rRNA can be used to distinguish the populations and species of Boophilus and Rhipicephalus studied here. Little support was found for the hypothesis that B. microplus from Australia and South Africa are different species. ITS 2 appears useful for phylogenetic inference in the Rhipicephalinae because in genetic distance, maximum likelihood, and maximum parsimony analyses, most branches leading to species had >95% bootstrap support. Rhipicephalus appendiculatus and R. zambeziensis are closely related, yet their ITS 2 sequences could be distinguished unambiguously. This lends weight to a previous proposal that Rhipicephcalus sanguineus and Rhipicephalus turanicus, and Rhipicephalus pumilio and Rhipicephalus camicasi, respectively, are conspecific, because each of these pairs of species had identical sequences for ca. 250 bp of ITS 2 rRNA. 相似文献
173.
The calcium dependence of ryanodine-sensitive single calcium channels was studied after fusing with planar lipid bilayers sarcoendoplasmic reticulum vesicles isolated from excitable tissues. Native channels from mammalian or amphibian skeletal muscle displayed three different calcium dependencies, cardiac (C), mammalian skeletal (MS), and low fractional open times (low Po), as reported for channels from brain cortex. Native channels from cardiac muscle presented only the MS and C dependencies. Channels with the MS or low Po behaviors showed bell-shaped calcium dependencies, but the latter had fractional open times of <0.1 at all [Ca2+]. Channels with C calcium dependence were activated by [Ca2+] < 10 microM and were not inhibited by increasing cis [Ca2+] up to 0.5 mM. After oxidation with 2,2'-dithiodipyridine or thimerosal, channels with low Po or MS dependencies increased their activity. These channels modified their calcium dependencies sequentially, from low Po to MS and C, or from MS to C. Reduction with glutathione of channels with C dependence (native or oxidized) decreased their fractional open times in 0.5 mM cis [Ca2+], from near unity to 0.1-0.3. These results show that all native channels displayed at least two calcium dependencies regardless of their origin, and that these changed after treatment with redox reagents. 相似文献
174.
The pharmacokinetics of both 2-oxothiazolidine-4-carboxylate (OTZ), a prodrug of cysteine, and total blood cysteine (cysteine plus cystine) were investigated in 18 healthy volunteers. OTZ was given either as a single, 2-hour intravenous infusion (56-66 mg/kg) or similarly infused (70-100 mg/kg) every 8 hours for four doses. Blood was assayed for OTZ, total blood cysteine, and glutathione. The pharmacokinetics of OTZ were analyzed alone and simultaneously with total cysteine using the NONMEM software package (University of California at San Francisco. The pharmacokinetics of OTZ were best described by Michaelis-Menten kinetics with parallel first-order elimination. OTZ was efficiently removed from the plasma. The Michaelis-Menten route of elimination was attributed to conversion of OTZ to total cysteine. At plasma OTZ concentrations equal to the Michaelis constant Km, 84% of OTZ was converted to total cysteine. These findings suggest that OTZ administered intravenously is an efficient means of increasing total blood cysteine. 相似文献
175.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Canadian Metallurgical Quarterly》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献
176.
JM Fernández AM Huescar P Ablanedo CJ Rábade FJ Pérez García JJ Rodríguez Martínez S Escaf 《Canadian Metallurgical Quarterly》1998,51(10):1029-1031
OBJECTIVE: To report on a rare case of primary leiomyosarcoma of the adrenal. To our knowledge, this is the fourth case reported in the literature. METHODS: A patient with primary leiomyosarcoma of the adrenal gland is presented. The clinical features are described, and the diagnostic and therapeutic aspects of this rare primary mesenchymal tumor are discussed. RESULTS/CONCLUSIONS: The aggressive nature and the poor prognosis of this rare tumor type are emphasized. 相似文献
177.
JA Beatty JJ Callanan A Terry O Jarrett JC Neil 《Canadian Metallurgical Quarterly》1998,72(1):767-771
We describe the histopathological, immunohistochemical, and molecular characterization of a lymphoma arising in a 7-year-old cat following experimental infection with feline immunodeficiency virus (FIV). The tumor was high grade and of B-cell lineage. The transformed cell had an immature phenotype (CD79a+, CD79b-, CD21-, immunoglobulin heavy and light chain negative), confirmed by antigen receptor gene analysis, which showed germ line configuration. Single-copy, clonally integrated FIV provirus was detected in tumor genomic DNA. FIV p24 antigen was not detected in tumor cells by immunostaining. This study provides the first evidence that the feline lentivirus may play a direct role in cell transformation under certain circumstances. 相似文献
178.
179.
B Herranz Jordán F Moreno Romero JJ Cardesa García I Santos Hurtado A Aparicio Palomino F Requena Guerrero 《Canadian Metallurgical Quarterly》1993,38(6):509-515
Eighty-one healthy prepubertal children of short stature, between two and twelve years of age, were divided into four homogeneous groups. Each group was treated with a placebo for one year and for a second year with one of the following drugs (double blind): clonidine (CI), arginine asprate (AA), ornithine alphaketoglutare (OKG), or cyproheptadine (Cp). CI and OKG did not better the standard deviation of height. AA and Cp did, but to no greater extent than the placebo. The growth rate did not change in any group. The ratio of bone age/chronological age was significantly higher at the end of the OKG year than at the end of the year with placebo, a difference that was not found in any other group. The prognosis of adult height (TW2) did not change in any group. The standard deviation of weight increased in all groups, both with the placebo and the various drugs, without significant differences between the groups. The CI caused frequent clinical side effects, including a reversible increase in transaminases in one child. The Cp stimulated hunger. The AA and OKG did not produce side-effects and the placebo increased appetite in 11% of the children. Somatomedin C was significantly higher after one year with Cp than after one year with the placebo, significantly higher after the placebo than after CI and AA and there was no difference between the treatment with the placebo and OKG. Growth hormone values in a 24 hour urine sample were so scattered that we do not consider them helpful.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
180.
Corneal transplantation is the most successful of organ transplants due to the fact that the eye is an immunologically privileged site, and the cornea is an immunologically privileged tissue. The factors responsible for this include presence of the blood-aqueous barrier, the avascularity of the cornea, the absence of classic antigen-presenting cells (APCs) in the central cornea, inhibitory factors in the aqueous humor, the phenomenon known as anterior chamber-associated immune deviation (ACAID), and the intraocular expression of Fas ligand. Loss of ocular immune privilege can occur with breaching of the blood-ocular barrier, corneal neovascularization, migration of classic APCs to the center of the cornea, loss of inhibitory factors in aqueous humor, abrogation of ACAID, and loss of Fas ligand expression within the anterior chamber. The purpose of this review is to analyze these events and how they relate to corneal graft rejection. A discussion on future research and therapeutic modalities is provided. 相似文献