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991.
Four cases of fatal diving accidents in Tasmania are presented, highlighting the role of CT in the investigation of diving fatalities. The CT technique allows rapid diagnosis when arterial gas embolism (AGE) is suspected. The traditional method of investigation, underwater autopsy, is a difficult procedure that requires specialized training in which the subtle diagnosis of AGE may be completely missed. Facilities for performing underwater autopsies are normally available only in tertiary referral centres, and therefore the diagnosis of AGE may be missed due to lack of facilities. The use of CT in the diagnosis of AGE in divers was first utilized in the early 1980s but has still not become widely adopted in forensic practice. This radiological technique has the advantage of being sensitive, quick, reliable, readily available and provides a permanent record. For hospitals that do not have a resident forensic pathologist, a CT scan can be easily performed and interpreted to eliminate the possibility of AGE. There are a number of pitfalls in the diagnosis of AGE with CT, particularly intravascular gas production following postmortem fermentation and off-gassing. Awareness of these pitfalls will help the radiologist in making a correct diagnosis of AGE. 相似文献
992.
毛细管气相色谱法测定复方利福平片中异烟肼和吡嗪酰胺的含量 总被引:4,自引:0,他引:4
目的:建立复方利福平片中异烟肼和吡嗪酰胺的含量测定方法。方法:毛细管气相色谱法,以乙酰苯胺为内标,色谱柱为弹性石英毛细管柱25m ×0 .32m m ×0 .52μm (DB1) ;柱温170 ℃;气化室温度250 ℃;检测器温度250 ℃;载气为高纯氮。结果:异烟肼和吡嗪酰胺的线性范围分别是0 .426 ~2 .13mgml 和1 .23 ~6 .13mgml;平均回收率分别为99 .81 % 和99 .63 % 。结论:方法简便,快速,准确,可作为该制剂的检测方法。 相似文献
993.
Seidenfeld J Samson DJ Aronson N Albertson PC Bayoumi AM Bennett C Brown A Garber A Gere M Hasselblad V Wilt T Ziegler K 《Evidence report/technology assessment (Summary)》1999,(4):i-x, 1-246, I1-36, passim
994.
In normal retinas, the phagocytosis of shed photoreceptor outer segments is mediated in part through a mannose receptor protein located in the apical retinal pigment epithelium membrane. As dystrophic rats of the Royal College of Surgeons have a defect in which the retinal pigment epithelium (RPE) is unable to phagocytize the shed outer segments, it is hypothesized that mannose receptor expression will be lost with the progression of photoreceptor degeneration. Immunohistochemical and molecular techniques have been used to study the developmental expression of the mannose receptor in normal and dystrophic retinal pigment epithelium. By immunofluorescence, the mannose receptor is localized to the retinal pigment epithelium, apical membrane region, beginning around 5 days postnatally in both normal and dystrophic retinas. In immunoblots, bands at 175 kDa are labelled by an anti-mannose receptor antibody in apical membrane samples from both normal and dystrophic RPE at all developmental times sampled. RT-PCR analysis reveals that mannose receptor message is present in normal and dystrophic RPE samples at all developmental time points examined. The present study demonstrates that the expression of the mannose receptor begins prior to outer segment differentiation and the initiation of phagocytosis in both normal and dystrophic RPE. Expression of the mannose receptor continues to be unchanged during the progression of photoreceptor degeneration in the dystrophic retina. 相似文献
995.
Baltussen RM Wielink G Stoevelaar HJ Van der Wilt GJ Severens JL Ament AJ 《World journal of urology》1998,16(2):142-147
The goal of this study was to assess the economic impact of introducing transurethral microwave thermotherapy (TUMT) in the
treatment of benign prostatic hyperplasia (BPH). Different scenarios were constructed using both randomized clinical trial
data and observational data on resource use related to BPH treatments. These include a baseline scenario, demand scenarios
reflecting the number of men who will be treated by TUMT when it is introduced, and supply scenarios reflecting the number
of hospitals that will provide TUMT. In the baseline scenario, costs of BPH treatment equal Netherlands guilders (NLG) 203 million.
If the demand for BPH treatment does not increase following the adoption of TUMT, costs may vary between NLG 187 and 189 million,
depending on how TUMT is provided. If the demand increases up to 25% following the introduction of TUMT, costs may vary between
NLG 457 and 466 million, depending on how TUMT is provided. The introduction of TUMT seems to be cost-saving, but savings
depend on the number of men who seek treatment for BPH. There is no indication for a controlled provision. 相似文献
996.
AS Patel TJ Harrington KS Saunt WK Jones 《Journal of Medical Imaging and Radiation Oncology》1996,40(2):185-186
The technique for construction of an agar-based ultrasound biopsy phantom is described. Features include tissue equivalent reflectivity, long life and non-shadowing targets. The phantom is useful for learning the necesary co-ordination between needle and probe for ultrasound needle guidance. This skill should initially be practised in vitro, on a device such as this. 相似文献
997.
Rate of radial bone mineral accretion in healthy children 总被引:2,自引:0,他引:2
WRO Goslings TJ Cole A Prentice NJ Bishop 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(4):383-387
Radial bone width and mineral content were measured in 392 healthy Cambridge children aged 6–12 years from a cohort of 420 children studied 2 years previously. The typical rate of bone mineral accretion was 0.044 g/cm/year for boys across the whole age range and 0.042 g/cm/year for girls up to a mean age of 9 years, rising rapidly thereafter in association with changes in body size. The factors best predicting bone mineral accretion rate were mean bone mineral content, mean height, height velocity, weight velocity and bone width velocity. After adjusting for anthropometry, age did not contribute to the model. These are the first available longitudinal reference data for the rate of radial bone mineral accretion in healthy children. 相似文献
998.
Pelvic ultrasound measurements in normal girls 总被引:2,自引:0,他引:2
IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):536-543
Pelvic ultrasound scans were carried out in 153 normal girls aged between 3 days and 14.9 years, in order to obtain reference data for ovarian volume, uterine length and uterine configuration. The right ovary was significantly larger than the left (by about 17%). Ovarian volume increased exponentially with age, over this age range. No relationship with pubertal stage (independent of age) could be demonstrated. Uterine length decreased from birth to 4 years, before steadily increasing. The fundalcervical ratio (FCR) decreased initially then increased to lie above 1.0 by 15 years of age. A midline endometrial echo was seen in half of the subjects aged less than 6 months, but otherwise it was not seen before 11.8 years of age or at Tanner stage B2. Smoothed reference centile curves for uterine length, right and left ovarian volume were produced, allowing z scores (or SD scores) to be calculated for each measurement. 相似文献
999.
JV Freeman TJ Cole S Chinn PR Jones EM White MA Preece 《Archives of disease in childhood》1995,73(1):17-24
The current reference curves of stature and weight for the UK were first published in 1966 and have been used ever since despite increasing concern that they may not adequately describe the growth of present day British children. Using current data from seven sources new reference curves have been estimated from birth to 20 years for children in 1990. The great majority of the data are nationally representative. The analysis used Cole's LMS method and has produced efficient estimates of the conventional centiles and gives a good fit to the data. These curves differ from the currently used curves at key ages for both stature and weight. In view of the concerns expressed about the current curves and the differences between them and the new curves, it is proposed that the curves presented here should be adopted as the new UK reference curves. 相似文献
1000.
Inhibition of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced lung tumorigenesis by dietary olive oil and squalene 总被引:2,自引:1,他引:2
Epidemiological studies have suggested that frequent olive oil consumption
may be a protective factor against lung cancer formation. Squalene, a
characteristic compound in olive oil, is an inhibitor of 3-
hydroxy-3-methylglutaryl coenzyme A reductase activity and has been
proposed to inhibit the farnesylation of ras oncoproteins. The present
study investigated the effect of dietary olive oil and squalene in a mouse
lung tumorigenesis model. Female A/J mice were fed AIN-76A diets containing
5% corn oil (control), 19.6% olive oil, or 2% squalene starting at 3 weeks
before a single dose of 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanone
(NNK) (103 mg/kg, i.p.). Animals were maintained on their respective diets
throughout the study. At 16 weeks after NNK administration, 100% of the
mice in the control group had lung tumors with a tumor multiplicity of 16
tumors per mouse. The olive oil and squalene diets significantly (P <
0.05) decreased the lung tumor multiplicity by 46 and 58%, respectively.
The squalene diet significantly (P < 0.05) decreased lung hyperplasia by
70%. In mice fed a diet containing 2% squalene for 3 weeks, the activation
of NNK was increased by 1.4- and 2.0-fold in lung and liver microsomes,
respectively, but its relationship to the inhibition of carcinogenesis is
not clear. These results demonstrate that dietary olive oil and squalene
can effectively inhibit NNK-induced lung tumorigenesis.
相似文献