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21.
R. S. Arora J. Mercer M. Thornley K. Tylee J. E. Wraith 《Journal of inherited metabolic disease》2007,30(5):821
Summary We describe a cohort of 14 Hurler–Scheie patients homozygous for the p.Leu490Pro missense mutation in the α-l-iduronidase gene. Now based in the UK, they are all of Pakistani/Kashmiri descent; 64% were female; 11/14 (79%) had a sibling
or cousin with MPS I and the parents are consanguineous in all cases. The median age at diagnosis was 1.8 years (range from
antenatal diagnosis to 16.5 years). Twelve were on ERT with recombinant human α-l-iduronidase (IDUA; Laronidase, Genzyme) for a median duration of 22.5 months (range 2–71 months) and median age at commencement
of ERT was 8.6 years (range 0.4–23.1 years). There was clear improvement in the size of liver and spleen as well as reduction
in urine glycosaminoglycans (GAGs). The mean (range) urine GAG levels in mg/mmol creatinine were 63.4 (28.9–105.6), 28.3 (10.9–41.4),
22.8 (12.1–43.1), 15.7 (9.2–24.8) and 16.3 (10.1–21.0) at commencement, 3 months post ERT, 6 months post ERT, 12 months post
ERT and 24 months post ERT, respectively. Effects on growth were not clear as there does not seem to be an obvious trend of
increase or decrease in height after commencement of ERT and this seems to be the case regardless of the age at which ERT
was started.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Online citation: JIMD Short Report #059 (2007) Online 相似文献
22.
23.
7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素的合成 总被引:1,自引:0,他引:1
以6-取代-2-喹诺酮-3-乙酸为侧链,用CDI法和潘化酯法与7-ADCA,7-ACA,7-ACT,和7-ACD缩合,合成了16个新的7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素类化合物,通过溶媒转提,葡聚糖凝胶(Sephadex LH-20)柱层析及离心薄层层析分离精制,得到纯品。初步体外抑菌试验表明:新化合物对革兰氏阳性及某些阴性菌具有高度敏感性。大多数化合物对所试试验菌的抗菌活性与头孢唑啉和青霉素G钠相当,有些比它们还强。 相似文献
24.
25.
Cell cycle regulation and the p53 tumor suppressor protein. 总被引:6,自引:0,他引:6
W E Mercer 《Critical reviews in eukaryotic gene expression》1992,2(3):251-263
Somatic mutations of the p53 gene have been implicated as causal events in the formation of a large number of common human tumors. Several lines of evidence suggest that the nuclear phosphoprotein encoded for by the wild-type gene (wt-p53) plays a role in regulating cell proliferation. Wt-p53 protein encodes a potent negative growth regulatory function that is lacking in mutant forms of the protein found in human tumors. In this review, the relationship between the expression of wt-p53 protein and cell proliferation is examined with emphasis on recent studies that provide clues as to the possible role that p53 plays in cell cycle regulation. A model for the action of p53 in regulating cell proliferation is proposed in which wt-p53 acts as a "checkpoint" protein to control the transit of cells through the restriction point in late G1-phase. After cells pass this "checkpoint" they become committed to enter S-phase and initiate DNA replication. This checkpoint function may be defective in cells that lack p53, express mutant p53, or in which the antiproliferative form of the protein is functionally inactive. Under these conditions stringent control of the initiation of DNA replication may no longer be possible, providing an environment conducive to the emergence oncogenic clones. 相似文献
26.
27.
Transforming potential of deletion mutants of the SV40 T antigen coding gene in Syrian hamster cells 总被引:2,自引:0,他引:2
Thymidine kinase-deficient syrian hamster cells were cotransfected with recombinant plasmids containing the thymidine kinase (TK) gene of Herpes Simplex Virus Type 1, and either intact or partially deleted SV40 T antigen-coding genes. The transformants were selected by their ability to grow in gHAT medium. After selection and cloning, the TK-positive transformants that also expressed T antigen were tested for the extent of their transformation with respect to a number of characteristics, which included saturation density, ability to grow in soft agar, resistance to butyrate and to dibutyryl-cAMP, and plating efficiency. The combined results of these various tests indicate that cells containing partially deleted SV40 T antigen-coding genes are less transformed than cells containing an intact SV40 T antigen-coding gene. However, the amounts of T antigen are lower in cells transformed by deletion mutants than in cells transformed by wild-type T antigen-coding gene. Our data indicate that both the quantity and the quality of T antigen may be important in determining the degree of transformation in Syrian hamster cells. 相似文献
28.
Functionally active complement proteins C6 and C7 detected in C6- and C7-deficient individuals 总被引:4,自引:2,他引:4
R. WÜRZNER A. ORREN P. POTTER B. P. MORGAN D. PONARD P. SPTH M. BRAI M. SCHULZE L. HAPPE O. G
TZE 《Clinical and experimental immunology》1991,83(3):430-437
Two sensitive sandwich ELISAs based on monoclonal antibodies directed to native C6 and C7 allowed the detection and quantitation of these complement proteins in 20 out of 37 serum samples from individuals who had previously been classified as deficient in these proteins as assessed by immunochemical and/or functional assays. Furthermore, serum from four C6-deficient and one combined C6-/C7-deficient individual showed an increase in the terminal complement complex (TCC) and a decrease in native C6 and C7 after complement activation as assayed by specific ELISAs. Despite their (incomplete) deficiencies, these individuals therefore possess functionally active terminal complement proteins with respect to their ability to generate the TCC. As these individuals have no history of a susceptibility to neisserial infections, even low concentrations of functionally active C6 and C7 may provide sufficient protection against those micro-organisms whose destruction requires TCC formation. 相似文献
29.
The purpose of the study was to investigate the characteristics of shock attenuation during high-speed running. Maximal running
speed was identified for each subject [n=8 males, 25 (SD 4.6) years; 80 (8.9) kg; 1.79 (0.06) m] as the highest speed that could be sustained for about 20 s on a
treadmill. During testing, light-weight accelerometers were securely mounted to the surface of the distal antero-medial aspect
of the leg and frontal aspect of the forehead. Subjects completed running conditions of 50, 60, 70, 80, 90, and 100% of their
maximal speeds with each condition lasting about 20 s. Stride length, stride frequency, leg and head peak impact acceleration
were recorded from the acceleration profiles. Shock attenuation was analyzed by extracting specific sections of the acceleration
profiles and calculating the ratio of head to leg power spectral densities across the 10–20 Hz frequency range. Both stride
length and stride frequency increased across speeds (P<0.05) and were correlated with running speed (stride length r=0.92, stride frequency r=0.89). Shock attenuation increased about 20% per m·s–1 across speeds (P<0.05), which was similar to the 17% increase in stride length per m·s–1. Additionally, shock attenuation was correlated with stride length (r=0.71) but only moderately correlated with stride frequency (r=0.40) across speeds. It was concluded that shock attenuation increased linearly with running speed and running kinematic
changes were characterized primarily by stride length changes. Furthermore, the change in shock attenuation was due to increased
leg not head peak impact acceleration across running speeds.
Electronic Publication 相似文献
30.
Bilateral simultaneous tubal sextuplets: pregnancy after in-vitro fertilization--embryo transfer following salpingectomy 总被引:2,自引:1,他引:2
The presence of a damaged tube has been suggested in recent studies to have
a negative effect on in-vitro fertilization (IVF) outcome. Performing
bilateral salpingectomy prior to IVF to maximize pregnancy rates may also
result in unnecessary surgery. This case is also an example of the
occurrence of interstitial pregnancy after salpingectomy. This unusual type
of ectopic pregnancy must be kept in mind when evaluating a patient
suspected of a possible early abnormal gestation after assisted
reproductive technolologies.
相似文献