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1.
Prenatal screening for Down syndrome using maternal serum markers achieves detection rates of 60-80% with a 5% false positive rate. Improvement in the accuracy of screening, as well as its ease and safety, will increase the use of such tests. The most effective of the current serum markers is human chorionic gonadotropin (hCG). Studies on beta core fragment (beta CF), the major urinary metabolite of hCG, have indicated that screening with beta CF and other markers measured in maternal urine might improve the detection of Down syndrome and provide a less expensive and simpler test. However, recent results have been unusually variable. Although it has great potential, the true clinical value of maternal urine screening to detect Down syndrome still remains to be determined.  相似文献   

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Antibodies specific for deoxynivalenol (DON) were prepared by immunizing rabbits with a deoxynivalenol-hemiglutaryl-HSA conjugate. The antibody showed cross-reactivity with DON, 15a-acetyl-DON (15-Ac DON), and 3a-acotyl-DON (3-Ac DON) of 100%, 216%, and 260%, respectively. No cross-reactivity was observed against 20 further trichothecenes of the A-, B-, and C-type. An indirect competitive ELISA procedure was set up for the detection of DON in liquid matrices occurring in the brewing process, Including beer. ELISA was sensitive down to 3.8 ng/mL. Detection limit for DON in tenfold diluted beer was 50 ppb. Recovery of the toxin in spiked beer was 45%, 77%, and 83% at toxin levels of 50; 500; and 1,000 ppb, respectively. ELISA results corresponded quite well with HPLC data. 196 commercial beers from several German breweries, including 36 gushing-positive samples, were assayed for DON. Screening revealed toxin levels from not detectable to 569 ppb. 69% of the gushing beers had marked levels of DON. 37% of the gushing-negative beer samples contained DON in detectable amounts with a maximum content of 172 ppb. Wheat beers had significantly higher DON-contents than beers derived from barley. Concentration of the toxin was significantly higher in gushing beers than in nongushing beers from both cereal sources.  相似文献   

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Most harbour porpoises found dead on the north-east coast of Scotland show signs of attack by sympatric bottlenose dolphins, but the reason(s) for these violent interactions remain(s) unclear. Post-mortem examinations of stranded bottlenose dolphins indicate that five out of eight young calves from this same area were also killed by bottlenose dolphins. These data, together with direct observations of an aggressive interaction between an adult bottlenose dolphin and a dead bottlenose dolphin calf, provide strong evidence for infanticide in this population. The similarity in the size range of harbour porpoises and dolphin calves that showed signs of attack by bottlenose dolphins suggests that previously reported interspecific interactions could be related to this infanticidal behaviour. These findings appear to provide the first evidence of infanticide in cetaceans (whales, dolphins and porpoises). We suggest that infanticide must be considered as a factor shaping sociality in this and other species of cetaceans, and may have serious consequences for the viability of small populations.  相似文献   

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Background

Although most idiopathic scoliosis patients subject to conservative treatment in daily clinical practice, there have been no ideal methods to evaluate the spinal flexibility for the patients who are scheduled the brace treatment. The purpose of this study was to investigate the value of hanging total spine x-ray to estimate the indicative correction angle by brace wearing in idiopathic scoliosis patients.

Methods

One hundred seventy-six consecutive patients with idiopathic scoliosis who were newly prescribed the Osaka Medical College (OMC) brace were studied. The study included 14 boys and 162 girls with a mean age of 13 years and 1 month. The type of curves consisted of 62 thoracic, 23 thoracolumbar, 22 lumbar, 42 double major, 14 double thoracic, and 13 triple curve pattern. We compared the Cobb angles on initial brace wearing (BA) and in hanging position (HA). Of those, 108 patients who had main thoracic curves were selected and evaluated the corrective ability of OMC brace. These subjects were divided into three groups according to the relation between BA and HA (BA < HA group, BA = HA group, and BA > HA group), and then, maturity was compared among them.

Results

The average Cobb angle in upright position (UA) of all cases was 31.0 ± 7.8°. The average BA and HA of all cases were 20.3 ± 9.5° and 21.1 ± 8.4°, respectively. The average chronological age was lowest in BA < HA group. And also, maturity in BA < HA group was the lowest among each of them. The rate of BA < HA cases were decreased as the Risser stage of the patients were progressed.

Conclusions

The use of hanging total spine x-ray served as a useful tool to estimate the degree of correction possible curve within the OMC brace for main thoracic curve in idiopathic scoliosis. Maturity had some influence on the correlation between HA and BA. Namely, in immature patients, HA tended to be larger than BA. In contrast, in mature patients, HA had a tendency to be smaller than BA. With consideration for spinal flexibility based on maturity, in mature patients, larger BA than HA may be allowed. However, in immature patients, smaller BA than HA should be aimed.  相似文献   

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OBJECTIVE--To analyse the cost-benefit of screening for and antihypertensive treatment of early renal disease indicated by microalbuminuria in patients with insulin dependent diabetes mellitus. DESIGN--Previously published data were used to estimate transition probabilities for each step from normoalbuminuria until death. The effect of intervention on urinary albumin excretion rate by antihypertensive treatment was arbitrarily set at three different levels. All direct costs (screening, antihypertensive treatment, treatment of end stage renal failure) were included in the cost-benefit analysis by using real discount rates of 2.5% and 6%. SETTING--Computer simulation. SUBJECTS--Simulated cohort of 8000 patients. MAIN OUTCOME MEASURES--Mortality, incidence of diabetic nephropathy, incidence of end stage renal failure, and costs versus savings. RESULTS--Assuming treatment effects of 33% and 67% median life expectancy increased by four to 14 years, respectively, and the need for dialysis or transplantation decreased by 21% to 63%. Costs and savings would balance if the annual rate of increase of albuminuria was decreased from 20% to 18% a year. CONCLUSIONS--Screening and intervention programmes are likely to have life saving effects and lead to considerable economic savings.  相似文献   

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Cystic Fibrosis (CF) is an autosomal recessive disease, caused by mutations in the Cystic Fibrosis Transmembrane Regulator gene (CFTR). The most frequent mutation in CF is ΔF508. The disease is clinically characterized by elevated concentrations of sweat chlorides and abnormally thick mucus. It affects organs such as lung, pancreas, gastrointestinal and reproductive tract. Women with CF commonly present delayed puberty and amenorrhea due to malnutrition. Our objective was to screen the presence of ΔF508 mutation in 24 women with altered fertility. Nine of these women presented reduced fertility without a known cause, four showed polycystic ovaries and two had early menopause. One woman with early menopause was a carrier of the ΔF508 mutation. Our study demonstrates that it is possible that the frequency of CF mutations among patients with altered fertility may be higher than expected. Previous data showed that fibrocystic women can show reduced fertility, maternal mortality associated with pregnancy and increased incidence of spontaneous abortion. We therefore recommend that women with reduced fertility undertake genetic tests for a better evaluation of pregnancy risks and clinical monitoring.  相似文献   

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The development of multiplex and flexible tests allowing the simultaneous analysis of pathogens presenting a transfusional risk is a real challenge. Current miniaturized platforms have been particularly marked by microarrays. These microsystems allow the optical detection of hundreds of individual targets simultaneously. However, they suffer from a low sensitivity and their combination with a preliminary target amplification step such as PCR is necessary. The variable level of expression of the infectious genomes of interest and their large diversity complicate multiplex amplification. Finally simultaneous analysis of multiple blood-transmitted agents poses numerous difficulties in diagnosis that remain unresolved by currently available technologies.Until recently, scientific and technological advances for pathogen detection have focused on target amplification and optical detection steps. Today, sample preparation is recognized as a critical area to improve. Nanotechnologies can reach the single-cell or molecular scale and consequently overcome several current technological obstacles. They offer new technological tools for improving sample preparation but also for avoiding target amplification and the current fluorescent labeling. The combination of nano-objects and nano-systems in current technologies offers new possibilities for potential applications in the detection of infectious agents.  相似文献   

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Research strategy in the auditory system has tended to parallel that in the visual system, where neurons have been shown to respond selectively to specific stimulus parameters. Auditory neurons have been shown to be sensitive to changes in acoustic parameters, but only rarely have neurons been reported that respond exclusively to only one biologically significant sound. Even at higher levels of the auditory system very few cells have been found that could be described as "vocalization detectors." In addition, variability in responses to artificial sounds have been reported for auditory cortical neurons similar to the response variability that has been reported in the visual system. Recent evidence indicates that the responses of auditory cortical neurons to species-specific vocalizations can also be labile, varying in both strength and selectivity. This is especially true of the secondary auditory cortex. This variability, coupled with the lack of extreme specificity in the secondary auditory cortex, suggests that secondary cortical neurons are not well suited for the role of "vocalization detectors."  相似文献   

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A retrospective study was conducted to examine the pattern of a disturbing increase in abnormal cervical smears in one health district. Past records over fifteen years (1965-79) were analysed to produce pick up rates according to age, screening state, severity of lesion, and area of residence. Main findings included an increased pick up rate in unscreened (5.8 to 12.9/1000 smears) and screened (0.9 to 3.6/1000 smears) women. The order of increase was proportionately much higher in women under 40 years. The only significant epidemiological variable in the catchment area was a substantial population increase, overweighted by the younger age groups. The principal conclusion of the study was that the increased pick up rates of abnormal cervical smears in the district reflected a true increase in the incidence of premalignant lesions of the cervix. Screening efforts aided by computerisation should be examined nationwide in order to reach high risk groups and thus try to prevent an increase in carcinoma of the cervix.  相似文献   

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