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81.
Ohne Zusammenfassung 相似文献
82.
83.
Minimal residual disease in childhood B-lineage lymphoblastic leukemia. Persistence of leukemic cells during the first 18 months of treatment 总被引:8,自引:0,他引:8
M Yamada R Wasserman B Lange B A Reichard R B Womer G Rovera 《The New England journal of medicine》1990,323(7):448-455
BACKGROUND. Whether patients in clinical remission for acute lymphoblastic leukemia (ALL) continue to harbor leukemic cells is not known, because methods of detecting residual malignant cells have not been sufficiently sensitive. This information might be useful for predicting recurrence and determining the duration of therapy. METHODS. Using a sensitive new method--identifying complementarity-determining region III sequences with the polymerase chain reaction--we estimated the number of residual leukemic cells in the bone marrow of eight children with B-lineage lymphoblastic leukemia before and after remission. RESULTS. Induction chemotherapy produced a 3-to-4-log reduction in the number of leukemic cells. In all samples obtained up to 18 months after diagnosis, however, 0.004 to 2.6 percent of bone marrow nucleated cells were residual leukemic cells. Among the four patients studied more than 18 months after diagnosis, three had no detectable leukemic cells in marrow samples. Despite this, one of them, who was no longer receiving therapy, had a central nervous system relapse. In one patient receiving maintenance chemotherapy, there was a 60-fold increase in leukemic cells three months before bone marrow relapse. CONCLUSIONS. The complete disappearance of leukemic cells (or their reduction below our method's threshold of detection, 1 in 100,000 cells) may be necessary to achieve a cure of ALL. The quantification of residual leukemic cells in serial marrow aspirates during therapy may allow the early detection of relapse. 相似文献
84.
Immunogenetic studies in families with rheumatoid arthritis and autoimmune thyroid disease. 下载免费PDF全文
P A Sanders D M Grennan P A Dyer G G de Lange R Harris 《Journal of medical genetics》1985,22(6):451-456
HLA and Gm typing were carried out in 16 families. Seven families included 10 sib pairs with rheumatoid arthritis (RA) and autoimmune thyroid disease (ATD) respectively, and nine families included 16 sib pairs with RA and circulating thyroid autoantibodies respectively. Eight, 11, and seven sib pairs with either RA or clinical or immunological evidence of ATD shared none, one, and two HLA haplotypes respectively, and two, seven, and two informative sib pairs shared none, one, and two Gm haplotypes respectively. This random haplotype sharing of HLA and Gm haplotypes suggests that non-HLA, non-Gm linked genes are likely to be involved in any genetic predisposition common to RA and ATD. 相似文献
85.
This article describes the histological and ultrastructural appearance of the interface created in the implantation bed, between bone tissue and implants made of dense sintered hydroxyapatite (HA). Biopsies from dog subjects included: a) loaded permucosal dental implants for tooth substitution, b) subperiosteally placed implants for alveolar bone correction, c) endosseously placed dental root implants to retain ridge form following extraction. The light and electron microscopical results show extensive bone apposition on the osseous sides of the implant surfaces. There is an intimate, direct bone contact without any visible interruption. The bone is of normal lamellar type and continuously connected with the trabecular bone. Bone has grown into the finest surface irregularities of the implant. Collagen fibers of the calcified bone matrix are observed within a distance less than 500 A from the implant surface. The thin (20-100 A) electron dense layer at the bone-implant interface resembled the lamina limitans of organic bone matrix, also seen at the inner walls of the osteocytes lacunes. Deposition of bone gives rise to a biologically stable bone-implant interface, without disturbance of the physiological bone turnover. This is seen as very favorable for desired long term fixation of implant to bone. 相似文献
86.
87.
Congenital anomalies and genetic disorders in families of children with central nervous system tumours. 下载免费PDF全文
S M Jones P C Phillips P T Molloy B J Lange M N Needle J A Biegel 《Journal of medical genetics》1995,32(8):627-632
Medical genetic histories of 165 children with primary central nervous system (CNS) tumours and 4599 relatives of these probands were examined to identify birth defects or genetic disorders that may be associated with the aetiology of CNS tumours. Twelve primary malignancies were found in 329 (4%) of the parents of probands. Two of 99 half sibs but no full sibs had malignancies. Twenty-four percent of families had histories warranting consultation for an inherited disorder or birth defect. Single instances of malformations or genetic disorders were reported in 36 families and several disorders were reported in more than one family, including familial hypercholesterolaemia (4), olivopontocerebellar atrophy (2), and familial abdominal aortic aneurysm (2). Although recurring abnormalities were not identified in probands, it is possible that one or more of the birth defects or genetic disorders observed in probands or relatives may be associated with CNS tumourigenesis. 相似文献
88.
Summary Varying host reaction of the house fly, Musca domestica L., to parasitism by the braconid Aphaereta pallipes (Say) was chiefly correlated with the diet of the host. Some evidence was found that implicated the strain of the host, the rearing temperatures, the ages of the parasitoid and the host, and the site of oviposition. Though development of A. pallipes embryos was inhibited before they became encapsulated with melanin within the host, the presence of the parasitoid and (or) the effect of its paralyzing toxin that was injected into the host just before oviposition prevented normal larval, pupal, or adult development of the six house fly strains tested. A considerable increase of parasitoid survival occurred when M. domestica larvae were reared on a chemically defined diet.
With 8 Figures in the Text
Formerly National Research Council Postdoctorate Fellow, Research Institute, Belleville, Ontario. 相似文献
Zusammenfassung Musca domestica L. reagierte unterschiedlich auf die Parasitierung durch die Braconide Aphaereta pallipes (Say). Die verschiedenen Reaktionen waren im wesentlichen mit der Art der Wirtsnahrung korreliert. Daneben finden sich Hinweise, daß auch der Wirtsstamm, dessen Zuchttemperatur, das Alter von Parasit und Wirt und der Eiablageort des Parasiten die Reaktionen beeinflussen. Obgleich die Entwicklung von Parasitenembryonen bereits gehemmt war, ehe sie innerhalb des Wirtes von Melanin eingeschlossen wurden, so verhinderten doch die Parasiten-embryonen und/oder die Wirkung der vor der Eiablage abgegebenen Paralysierungstoxine die normale Entwicklung der Wirte aus sechs Fliegenstämmen. Eine beträchtliche Steigerung der Überlebensrate der Parasiten trat ein, wenn M. domestica-Larven in einem Gemisch chemisch genau definierter Nahrung gezogen wurden.
With 8 Figures in the Text
Formerly National Research Council Postdoctorate Fellow, Research Institute, Belleville, Ontario. 相似文献
89.
R L Vessella V Alvarez R K Chiou J Rodwell M Elson D Palme R Shafer P Lange 《NCI monographs : a publication of the National Cancer Institute》1987,(3):159-167
From a panel of monoclonal antibodies (MAb) reactive with human renal cell carcinoma generated by this laboratory, three (designated A6H, C5H, and D5D) were selected for in vivo studies with a nude mouse xenograft model. These studies included 131I- and 111In-labeled MAb radioimmunoscintigraphy and 131I-labeled MAb radioimmunotherapy. In the imaging studies, these radiolabeled MAb allowed visualization of subcutaneous xenografts larger than 40 mg and subrenal capsule xenografts smaller than 20 mg. Comparisons of tumor to non-tumor tissue radiolabel distribution yielded unusually high ratios and depended on the MAb-xenograft combination. The 111In-radiolabeled A6H showed increased accumulation in the liver compared with 131I-A6H, but this still did not necessitate background subtraction for good visualization of small, subrenal capsule renal cell carcinoma xenografts. Radioimmunotherapy studies with 131I-A6H in BALB/c nu/nu mice bearing established renal cell carcinoma xenografts showed a prolonged (greater than 90 days) regression in tumor burden and possible "cures," whereas three sets of control mice showed progressive and rapid increases in tumor size. These studies indicated that MAb, which show good tissue biodistribution and high imaging sensitivity, could also be capable of delivering effective radiotherapy to the tumor when "human equivalent" radiolabeled-MAb doses are used. 相似文献
90.
R. Lange P. Rowe L. Seebauer J. Mathews J. R. Siewert W. Silen 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1984,364(1):539-539
Zusammenfassung Der Mechanismus der Cytoprotektion von Prostaglandin (PG) auf die Magenmucosa ist unbekannt. Anaesthesierte Kaninchen erhielten in der Gruppe (GR) I (n=8) im. Aspirin (ASA) (100 mg/kg als Bolus, 66 mg/kg/h kontinuierlich) in der GR 11 (n=10) NaCI und in der GR III (n=7) zusätzlich zum ASA, PGE I (0,1 g/kg/min) als Infusion über 120 min. Der Mucosa-Blutfluß (MBF) wurde mit radioaktiven Mikrosphären gemessen. In der GR I fiel der MBF nach 15 min um 72,3+3,8% (+ SEM) und nach 120 min um 73,1+3,8% (p 0,05 gegen % Änderung in GR II und III). Nach 120 min zeigte sich in der GR I 19,8 + 7,6% der Fundusmucosa hämorrhagisch, in der GR 11 6,1 +5,2% und in der GR 1112,0+ 1,4% (p 0,05 gegen GR II und III). Wir schließen, daß der cytoprotektive Effekt des PGE I auf einer Aufhebung der ASA bedingten Mucosaischämie beruht. 相似文献