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排序方式: 共有5968条查询结果,搜索用时 15 毫秒
961.
Identification of the chromosome 14 origin of a C-negative marker associated with a 14q32 deletion by chromosome painting 总被引:1,自引:0,他引:1
I Magnani N Sacchi M Darfler PE Nisson R Tornaghi AM Fuhrman-Conti 《Canadian Metallurgical Quarterly》1993,43(4):180-185
A constitutional chromosome 14 rearrangement was observed in a female with a psychodevelopmental disorder. Karyotype analysis using a variety of chromosome techniques, QFQ, GTG, CBG, Ag-NOR and DA-DAPI, showed a deletion of chromosome 14q32.1-qter region in association with a supernumerary marker chromosome. The marker, resembling a submetacentric, approximately half the size of a G group chromosome is C band and Ag-NOR negative. The heteromorphism of the satellites showed that the deleted chromosome 14 is paternal in origin. Chromosome painting using an Alu-PCR probe specific for the human chromosome 14 and fluorescent in situ hybridization (FISH) showed that the marker contains chromosome 14q32 sequences. It is likely that the marker was generated from the deleted chromosome 14 region through a complex rearrangement. 相似文献
962.
963.
OBJECTIVE: To assess the effect of aluminum hydroxide/magnesium hydroxide antacid and bismuth subsalicylate on gastric pH in clinically normal horses and to develop guidelines on the use of these agents for treatment of peptic ulcer disease in horses. DESIGN: Prospective, randomized, controlled trial. ANIMALS: 5 clinically normal adult horses with chronically implanted gastric cannulas. PROCEDURE: Each horse received all 5 treatments (30 g of aluminum hydroxide/15 g of magnesium hydroxide, 12 g of aluminum hydroxide/6 g of magnesium hydroxide, 10.5 g of bismuth subsalicylate, 26.25 g of bismuth subsalicylate, and 5% methylcellulose control) with only 1 experiment performed each day. Gastric pH was measured via a glass electrode inserted through the gastric cannula for 1 hour before treatment and continued for 2 hours after treatment. Food or water was not given to the horses during the experiment. Measurements of gastric pH obtained during posttreatment hours were compared with pretreatment gastric pH values. RESULTS: Only a dose of 30 g of aluminum hydroxide/ 15 g of magnesium hydroxide resulted in a significant increase in gastric pH over baseline or control values. Mean pH was 5.2 +/- 0.62 and 4.59 +/- 0.48 for posttreatment hours 1 and 2, respectively. CLINICAL IMPLICATIONS: Oral administration of 30 g of aluminum hydroxide/15 g of magnesium hydroxide to adult horses should result in a mean hourly gastric pH > or = 4.0 for at least 2 hours. 相似文献
964.
M Bronstein J Salazar R Monserat C Gumina H Gori AM Isern C Fernandez M Salamanca D Fuentes MJ Sanchez 《Canadian Metallurgical Quarterly》1993,47(3):162-164
A 78-year-old woman complained of ocular pain in the right eye. Thirty-three months before, the patient had a pterygium excised and mitomycin C, 0.04%, was instilled 3 times a day postoperatively for 10 days in the right eye. The same surgery was performed and the same drug was used for a course of 5 days in the left eye. Corneoscleral ulceration and corneal performation occurred in the right eye. The lesions were successfully treated with a lamellar patch graft with reserved corneosclera. We believe that it may not be safe to instill 0.04% mitomycin C 3 times a day postoperatively for 10 days. 相似文献
965.
AM Cirla N Sforza GP Roffi A Alessandrini R Stanizzi N Dorigo E Sala F Della Torre 《Canadian Metallurgical Quarterly》1996,51(5):299-305
A double-blind, placebo-controlled study was carried out to test the clinical efficacy and safety of local nasal immunotherapy (LNIT) in powder form. Twenty-two patients suffering from allergic rhinitis strictly associated with early spring symptoms, with positive skin prick tests and RAST for birch-alder, all responders to a specific nasal provocation test (NPT), received randomly active or placebo treatment for 4 months. Immunotherapy consisted of administration of a set of capsules containing progressively increasing amounts of birch (Betula pendula) and speckled alder (Alnus incana) allergens in powder form with controlled granulometry. The active (birch-alder) and placebo (lactose) group completed the treatment according to a similar schedule. During the pollen season (March-April), the patients who took the active treatment reported less sneezing and rhinorrhea than the placebo group, on the basis of a symptoms score, and the differences were statistically significant; the need for drugs (terfenadine) was also significantly reduced. These findings agreed well with the results of specific NPT after the treatment; only patients in the active group had a higher threshold dose of nasal specific reactivity to birch-alder allergens than in tests before the LNIT. 相似文献
966.
Substitution enterocystoplasty is becoming more common in a selected group of patients. Acute or chronic ischemia is an exceptional event. We describe the clinical manifestations and management of chronic ischemia of a neobladder that occurred weeks after a successful initial operation. The possible mechanisms responsible for this complication are reviewed. 相似文献
967.
968.
C He AG Rusu AM Poplawski JA Irwin JM Manners 《Canadian Metallurgical Quarterly》1998,150(4):1459-1466
Two biotypes (A and B) of Colletotrichum gloeosporioides infect the tropical legumes Stylosanthes spp. in Australia. These biotypes are asexual and vegetatively incompatible. However, field isolates of biotype B carrying a supernumerary 2-Mb chromosome, thought to originate from biotype A, have been reported previously. We tested the hypothesis that the 2-Mb chromosome could be transferred from biotype A to biotype B under laboratory conditions. Selectable marker genes conferring resistance to hygromycin and phleomycin were introduced into isolates of biotypes A and B, respectively. A transformant of biotype A, with the hygromycin resistance gene integrated on the 2-Mb chromosome, was cocultivated with phleomycin-resistant transformants of biotype B. Double antibiotic-resistant colonies were obtained from conidia of these mixed cultures at a frequency of approximately 10(-7). Molecular analysis using RFLPs, RAPDs, and electrophoretic karyotypes showed that these colonies contained the 2-Mb chromosome in a biotype B genetic background. In contrast, no double antibiotic colonies developed from conidia obtained from mixed cultures of phleomycin-resistant transformants of biotype B with biotype A transformants carrying the hygromycin resistance gene integrated in chromosomes >2 Mb in size. The results demonstrated that the 2-Mb chromosome was selectively transferred from biotype A to biotype B. The horizontal transfer of specific chromosomes across vegetative incompatibility barriers may explain the origin of supernumerary chromosomes in fungi. 相似文献
969.
970.
EP Ivanov GV Tolochko LP Shuvaeva S Becker E Nekolla AM Kellerer 《Canadian Metallurgical Quarterly》1996,35(2):75-80
Childhood leukemia (ICD 204-208 [1]) incidence rates in the different regions of Belarus are reported for a period before and after the Chernobyl accident (1982-1994). There are, at this point, no recognizable trends towards higher rates. 相似文献