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41.
Holyoake TL; Freshney MG; McNair L; Parker AN; McKay PJ; Steward WP; Fitzsimons E; Graham GJ; Pragnell IB 《Blood》1996,87(11):4589-4595
The characterization of many cytokines involved in the control of hematopoiesis has led to intense investigation into their potential use in ex vivo culture to expand progenitor numbers. We have established the optimum ex vivo culture conditions that allow substantial amplification of transient engrafting murine stem cells and which, simultaneously, augment the ability to sustain serial bone marrow transplantation (BMT). Short-term incubation of unfractionated BM cells in liquid culture with stem cell factor (SCF) and interleukin-11 (IL- 11) produced a 50-fold amplification of clonogenic multipotential progenitors (CFU-A). Following such ex vivo expansion, substantially fewer cells were required to rescue lethally irradiated mice. When transplanted in cell doses above threshold for engraftment, BM cells expanded ex vivo resulted in significantly more rapid hematopoietic recovery. In a serial transplantation model, unmanipulated BM was only able to consistently sustain secondary BMT recipients, but BM expanded ex vivo has sustained quaternary BMT recipients that remain alive and well more than 140 days after 4th degree BMT. These results show augmentation of both short-term recovery posttransplant and the ability to serially transplant marrow by preincubation in culture with SCF and IL-11. 相似文献
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44.
Hendrickx J; Dams E; Coucke P; Lee P; Fernandes J; Willems PJ 《Human molecular genetics》1996,5(5):649-652
X-linked liver glycogenosis type II (XLG II) is a recently described X-
linked liver glycogen storage disease, mainly characterized by enlarged
liver and growth retardation. These clinical symptoms are very similar to
those of XLG I. In contrast to XLG I patients, however, XLG II patients do
not show an in vitro enzymatic deficiency of phosphorylase kinase (PHK).
Recently, mutations were identified in the gene encoding the liver alpha
subunit of PHK (PHKA2) in XLG I patients. We have now studied the PHKA2
gene of four unrelated XLG II patients and identified four different
mutations in the open reading frame, including a deletion of three
nucleotides, an insertion of six nucleotides and two missense mutations.
These results indicate that XLG II is due to mutations in PHKA2. In
contrast to XLG I, XLG II is caused by mutations that lead to minor
structural abnormalities in the primary structure of the liver alpha
subunit of PHK. These mutations are found in a conserved RXX(X)T motif,
resembling known phosphorylation sites that might be involved in the
regulation of PHK. These findings might explain why the in vitro PHK
enzymatic activity is not deficient in XLG II, whereas it is in XLG I.
相似文献
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46.
Accurate pregnancy dating is vital to obstetric management. However, first trimester fetal charts commonly used in Australia rely on data reported more than three decades ago. This study reports first trimester dating and growth charts for crown‐rump length between 5 and 14 weeks of gestation and biparietal diameter between 9 and 14 weeks of gestation on an Australia population using modern real‐time ultrasound equipment. All consenting eligible women attending a large Sydney clinic for first trimester ultrasound between March 2005 and December 2006 were recruited. Measurements were carried out to Australasian Society for Ultrasound in Medicine standard protocols. Statistical analyses were undertaken using polynomial regression models and thorough diagnostic checks made. Overall 396 eligible women consented to the study, with 268 between 9 and 14 weeks of gestation. The average participant age was 34 years (range 22–45 years), 371 and all yielded valid biometry measurements. Equations, means and 90% reference intervals for crown‐rump length measurements and biparietal diameter measurements were derived using polynomial regression models. Thorough residual and diagnostic checks were made. Once validated by others, we believe they will warrant consideration for use by Australasian Society for Ultrasound in Medicine. 相似文献
47.
ÅM Jakobson A Kreuger Ö Mortimer S Henningsson H Seidel PJ Moe 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(4):359-361
Two patients aged 11 and four years, were accidentally given a 10-fold overdose of intrathecal methotrexate while being treated for malignant disease. Neither patient developed any signs of neurotoxicity and exchange of lumbar cerebro-spinal fluid was started 3 and 5 h later, respectively. In one of the patients, who received 120 mg of methotrexate intrathecally, 31% of the given dose was recovered during 2 h of cerebrospinal fluid exchange that was started 3 h after the accidental overdosage. No sequelae were observed in any of the patients. Cerebrospinal fluid exchange is safe and can be recommended in all cases of intrathecal methotrexate overdosage. Ventriculo-cisternal perfusion is not necessary in cases of a 10-fold overdose if the patient has no signs of acute neurotoxicity. 相似文献
48.
WM Bisset P Stapleford S Long A Chamberlain B Sokel PJ Milla 《Archives of disease in childhood》1992,67(1):109-114
In children with severe failure of intestinal function, intravenous nutrition is at present the only treatment able to maintain adequate nutrition for prolonged periods of time. Over the last five years we have discharged 10 patients home on parenteral nutrition for a total of 25 patient years and here the outcome of these children is presented. Of the 10 patients, one has discontinued home parenteral nutrition (HPN), seven patients remain well, one patient has recently moved to the USA, and one patient has died after major abdominal surgery. All children had either normal or an accelerated rate of growth on HPN and developmentally all have progressed well. All the children over 5 years attend normal schools. The major complication of treatment was line sepsis with an overall rate of one episode in 476 days and a total of nine central lines (five patients) have required replacement giving an average line life of 680 days. For those children unfortunate enough to suffer from severe intestinal failure, HPN is preferable to prolonged hospital treatment and offers the chance of a good quality of life with prolonged survival. 相似文献
49.
JN HANNA WL SEXTON JL FAOAGALI PJ BUDA ML KENNETT KA BRUSSEN 《Journal of paediatrics and child health》1995,31(4):345-349
Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children. 相似文献
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children. 相似文献
50.
SL Stuckey EJ Gilford PJ Smith M Kean 《Journal of Medical Imaging and Radiation Oncology》1995,39(4):350-355
This preliminary study was designed to investigate the ability of multiple axial volume three-dimensional fourier transform (3DFT) time-of-flight (TOF) magnetic resonance angiography (MRA) to depict the carotid bifurcation in the early post-carotid endarterectomy period. Five patients underwent intra-operative digital subtraction angiography (DSA) and carotid MRA within 5 days of carotid endarterectomy. An axial volume fast imaging in steady-state precession (FISP) gradient-echo 3DFT TOF carotid MRA technique in this limited series appeared to display accurately the surgically significant abnormalities at the carotid bifurcation after endarterectomy. However, in normal or near-normal intra-operative DSA studies, overestimation of internal carotid artery stenoses was encountered. Postoperative MRA demonstrates potential as a useful non-invasive investigation after carotid endarterectomy but should be interpreted with caution until larger studies become available. 相似文献