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41.
D. M. Reid I. Mackay S. Wilkinson C. Miller D. G. Schuette J. Compston C. Cooper E. Duncan N. Galwey R. Keen B. Langdahl A. McLellan H. Pols A. Uitterlinden J. O’Riordan J. A. H. Wass S. H. Ralston S. T. Bennett 《Osteoporosis international》2006,17(1):125-132
Osteoporosis is a common disease with a strong genetic component characterized by reduced bone mass and an increased risk of fragility fractures. Bone mineral density (BMD) is the most important determinant of osteoporotic fracture risk, but the genes responsible for BMD regulation and fracture are incompletely defined. To enable multi-center studies to examine the genetic influences on BMD there is a requirement to standardize measurements across different manufacturers of bone densitometers, different versions of machines and different normative ranges. This paper describes a method developed to allow near-identical subjects with low age-adjusted BMD (based on Z-scores) to be recruited in 17 centers using 27 different densitometers. Cross-calibration was based on measurements using a European spine phantom circulated to all centers and measured ten times on each individual machine. From theses values an individual exponential curve, based on nominal versus observed BMD, was derived for each machine. As expected, there were large and significant variations in nominal BMD values, not only between scanners from different manufacturers but also between different versions of scanners from the same manufacturer. Hologic scanners tended to underestimate the nominal BMD, while Lunar scanners overestimated the value. Norland scanners gave mixed values over estimating BMD at the lower nominal value (0.5 g/cm2) while underestimating the value at the higher value (1.5 g/cm2). The validity of the exponential equations was tested using hip and spine measurements on 991 non-proband women from a familial osteoporosis study (FAMOS). After cross-calibration there was a considerable reduction in variation between machines. This observation, coupled with the absence of a similar reduction in variation attributable to a linear regression on age, demonstrated the validity of the cross-calibration approach. Use of the cross-calibration curves along with a standard normative range (in the case of this study, the Hologic normative range) allowed age-specific Z-scores to be used as an inclusion criterion in this genetic study, a method that will be useful for other trials where age-specific BMD inclusion criteria are required. 相似文献
42.
M. M. Marchenko G. P. Kopyl’chuk I. A. Shmarakov O. V. Ketsa V. N. Kushnir 《Pharmaceutical Chemistry Journal》2006,40(6):296-297
The antitumor activity of 5-(5′,6′-benzocoumaro-3′-yl)methylaminouracil (BCMU) and its liposomal medicinal form was studied
in comparison to 5-fluorouracil (5-FU), a well-known antitumor drug widely used in oncological practice. The half-lethal dose
of BCMU is 14.8 ± 4.2 mg/kg, while the optimum effective dose of the drug is 6 mg/kg. In this dose, BCMU combines low toxicity
with significant antitumor activity, which is manifested by increased tumor growth inhibition (TGI) at a 19% increase in the
lifetime (LT) of experimental animals. The antitumor activity of the liposomal form of BCMU is quantitatively and qualitatively
superior to that of the nonmodified compound and 5-FU, which is manifested by the most pronounced TGI value and by a significant
LT increase.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 6, pp. 6–7, June, 2006. 相似文献
43.
The trypanosome responsible for the majority of cases of human trypanosomiasis in Africa is Group 1 Trypanosoma brucei gambiense. Currently the most reliable test for the parasite is based on a single gene, which encodes a 47 kDa receptor-like T. b. gambiense-specific glycoprotein, TgsGP, expressed in the flagellar pocket of bloodstream forms. Although TgsGP has been demonstrated in T. b. gambiense throughout its geographic range, similar genes have been demonstrated in other T. brucei sspp. isolates, and there are no data on the extent of sequence variation in TgsGP. Here we have carried out a comparison of TgsGP sequences in a range of Group 1 T. b. gambiense isolates and compared the gene to homologues in other T. brucei sspp. in order to provide information to support the use of this gene as the key identification target for Group 1 T. b. gambiense. We demonstrate that the sequence of TgsGP is well conserved in Group 1 T. b. gambiense across the endemic range of gambian human trypanosomiasis and confirm that this gene is a suitable target for specific detection of this parasite. The TgsGp-like genes in some isolates of T. b. brucei, T. b. rhodesiense and Group 2 T. b. gambiense are closely similar to VSG Tb10.v4.0178, which may be the ancestral gene from which TgsGP was derived. 相似文献
44.
45.
目的 探讨紫外线照射充氧(UBIO)对梭曼急性中毒家兔全血乙酰胆酯酶(AchE)活性的影响及对梭曼中毒后肺损伤的治疗作用.方法 家兔40只,随机分为正常对照组、中毒组、常规治疗组及UBIO治疗组各10只,于治疗后2h检测全血AchE 活性及进行动脉血气分析.收集支气管肺泡灌洗液(BALF),分析其中碱性磷酸酶(AKP)、酸性磷酸酶(ACP)活性.结果 中毒组AchE活性显著低于对照组(P<0.01),BALF中AKP及ACP活性高于对照组(P<0.01).经UBIO治疗后AchE活性升高,且明显高于中毒组及常规治疗组.与中毒组比较,UBIO治疗组中AKP及ACP活性显著降低(P<0.05),而动脉血pH值、PaO2及SaO2明显升高(P<0.05),PaCO2明显降低(P<0.05).结论 UBIO能提高全血AchE活性及减轻梭曼中毒后的肺损伤,因而可能是一新的治疗梭曼急性中毒的途径. 相似文献
46.
47.
Yongquan Yin Wenpo Shan Xia Ji Xingyan Deng Jian’an Cheng Laimin Li 《Bulletin of environmental contamination and toxicology》2010,85(1):10-14
The levels and temporal variations of surface ozone at a coastal site in East China during summer and autumn were analyzed
and the influences of meteorological parameters on ozone were investigated. An inland city was chosen as a comparison site.
The main results and conclusions of this study are: (1) ozone pollution, with a maximum 1 h concentration of 150.98 ppbv,
was severe during summer and autumn at the coastal site; (2) the ozone level was obviously higher at the coastal site than
that at the inland site in September; (3) besides temperature and solar radiation, sea-land breeze circulation is an important
factor influencing the ozone level at the coastal site, and sea breeze often induce high ozone levels (the average ozone concentration
for sea breeze was about 13 ppbv higher than that for land breeze). 相似文献
48.
J. Holstein D. Farge N. Taright L. Trinquart D. Manac’h T. Bastianic G. Chatellier 《Revue d'épidémiologie et de santé publique》2009,57(3):205-211
BackgroundSeveral studies have shown that socioeconomic deprivation is associated with increased hospitalization lengths of stay (LOS) and costs. Yet, the French DRG-based information system (PMSI) does not take deprived situations into account. Hence, we aimed at extracting routinely available variables measuring deprivation from the Hospital Information System and at assessing their association with severity of illness and hospital LOS.MethodsWe performed record linkage between the PMSI database concerning stays of patients aged more than 16 years in the short-stay sector of Assistance publique–Hôpitaux de Paris in 2007 and an administrative database which provided the following deprivation measures: recipients of Couverture Médicale Universelle (basic or complementary health insurances adapted for underprivileged French citizens) or Aide Médicale d’État (health and medical emergency insurances adapted for underprivileged non French citizens living in France) and homeless patients. We compared length of stays showing a deprivation measure to others after adjustment on morbidity, age and sex.ResultsAmong 352,721 stays, the prevalence of the deprivation measures ranged from 0.71% for “homelessness” to 6.24% for complementary Couverture Médicale Universelle. Stays showing a deprivation measure had specific illnesses and had more frequently associated comorbidities or complications than others. After adjustment, deprivation measures were associated with significantly increased LOS (by 5% for Couverture Médicale Universelle to 48% for emergency Aide Médicale d’État.ConclusionRoutine extraction of deprivation measures from Hospital Information Systems is feasible. Age, sex and illness being equal, these deprivation measures were associated with more complicated cases and increased LOS. We recommend that case mix-based hospital prospective payment systems take socioeconomic deprivation into account. 相似文献
49.
Justine Royle Rachel Williamson Mark Strachan Marie O’Donnell Simon Jackson Thanos Argryopoulos Alan McNeill 《British journal of medical & surgical urology》2009,2(5):204-207
Emphysematous pyelonephritis is a severe life-threatening infection which continues to carry significant morbidity and mortality. We present a case recently managed at our institution by laparoscopic nephrectomy. The patient survived, and in comparison to some of the more conventionally managed patients in the literature, made an extremely speedy recovery. We would advocate this option to be seriously considered when patients are suitable and appropriately trained surgeons are available. 相似文献
50.