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71.
The sD gene of Aspergillus nidulans has been cloned by heterologous screening of rationally selected cosmids. Co-transformation of the sD50 mutant JMP1 confirmed the presence of a functional gene. Sequence analysis determined this gene to be 680 bp in length, containing a 59-bp intron and encoding a protein of 206 amino acids. A protein-sequence comparison revealed a similarity to the C-terminal region of ATP sulphurylase, the sC gene product. Further sequence comparison revealed differences in a consensus sequence ATP-binding motif, indicating non-functionality of the APS kinase-like domain of ATP sulphurylase, and confirms sD as the gene encoding APS kinase in A. nidulans. Received: 17 April / 29 August 1997  相似文献   
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Oscillatory motion of the normal cervical spinal cord   总被引:2,自引:0,他引:2  
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Fourteen adult patients (mean age 22.5 years, range 18–35) with cystic fibrosis undertook nocturnal nasogastric feeding for a mean period of 14.7 (range 6–18) months consuming an average of 1042 ml of a high energy feed on five nights of each week. Following this protocol all patients gained weight (mean weight gain 5.4 kg, range 2–17). For the group as a whole, lung function remained stable during the period of feeding; however a significant correlation between improvement in lung function and weight gain was demonstrated. Hyperglycaemia during feeding in this adult population was common (9/14, 64%) but was easily controlled with insulin therapy.  相似文献   
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Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
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76.
Osteointegration of bone graft in porous-coated total hip arthroplasty   总被引:1,自引:0,他引:1  
Since 1983, 19 patients have had bone grafting of acetabular defects in association with a porous-coated acetabular prosthesis. The defects were defined by anatomic location to assess the rates of incorporation at different sites. The average time to incorporation was 12 months, judged by trabecular continuity. Superolateral grafts showed a greater degree of rarefaction than medial grafts. Nonprogressive migration of the graft was seen in only two cases before full incorporation of the graft. Developing lucency was seen up to 2 mm at the prosthesis-graft interface but not at the graft-ilium level. Roentgenograms suggested that integration of porous acetabular prostheses into bone may improve results of reconstructive surgery of the acetabulum.  相似文献   
77.
Completeness of cancer registration has not been consistently ascertained across different registries. This report describes how capture-recapture methods have been used to estimate completeness at the Ontario Cancer Registry. The method was applied in two fashions; first, using three data sources in a modeling approach: and second, using two data sources and standard, simple capture-recapture methods. The modeling approach is more flexible, since several variables that influence cancer registration can be considered and can be used to identify reporting patterns of different data sources. In the present analysis, estimates of completeness of the registry as a whole were remarkably similar using either two or three data sources, and site-specific comparisons differed by at most 7%. Because of the advantages of capture-recapture methods-estimation of level of completeness, possible comparability of estimates across different registries, and versatility to consider other determinants of cancer registration-a plea for greater use of these methods in cancer registration is made.  相似文献   
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In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
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