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排序方式: 共有467条查询结果,搜索用时 31 毫秒
1.
The molluscicidal potency of ground seed pods of Swartzia madagascariensis was tested in the laboratory against Marisa cornuarietis, a well known competitor and/or predator of pulmonate intermediate hosts of schistosomiasis. Results showed that a minimum concentration of 1.6g ground pods/1 was required to cause 100% mortality in M. cornuarietis. This concentration was by far over and above what is required (ie, 100 mg ground pods/1) to kill 10% of the pulmonate hosts of schistosomiasis. It seems that the application of S. madagascariensis at a concentration inimical to pulmonates (ie, 100 mg ground ponds/1 or slightly higher) in habitats where M. cornuarietis is introduced may not adversely affected to competitor snail population. Hence, the prospect of using S. madagascariensis in conjunction with M. cornuarietis against pulmonate snail hosts is conceived and tentatively recommended. 相似文献
2.
Over the past decade, the unfortunate reality is that the income gap has widened between Canadian families. Educational outcomes are one of the key areas influenced by family incomes. Children from low-income families often start school already behind their peers who come from more affluent families, as shown in measures of school readiness. The incidence, depth, duration and timing of poverty all influence a child’s educational attainment, along with community characteristics and social networks. However, both Canadian and international interventions have shown that the effects of poverty can be reduced using sustainable interventions. Paediatricians and family doctors have many opportunities to influence readiness for school and educational success in primary care settings. 相似文献
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Contraceptive potential of a mifepristone-nomegestrol acetate sequential regimen in women 总被引:1,自引:0,他引:1
Croxatto HB; Salvatierra AM; Fuentealba B; Massai R 《Human reproduction (Oxford, England)》1998,13(12):3297-3302
The effectiveness of a sequential regimen consisting of mifepristone, 10
mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for
the next 13 days, for inhibiting ovulation and maintaining regular bleeding
cycles was assessed in 10 surgically sterilized volunteers who were
followed for one pretreatment and three treated cycles. Hormonal
determinations in blood and urine, ovarian ultrasonography, bleeding
records in all cycles and an endometrial biopsy taken on day 22-25 of the
third treatment cycle were used to monitor the effects of treatment. During
treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l)
and six biphasic cycles were recorded. Nine follicular ruptures were
detected echographically in these 30 treated cycles, five of which occurred
in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA
treatment. Echographic and endocrine features of ovulatory cycles were both
present in only four treated cycles (13.3%). Development of a secretory
endometrium was achieved in all cases, but it was always irregular. Regular
withdrawal bleeding occurred in all subjects and no adverse reactions were
recorded. The ovarian and endometrial effects of this regimen justify
testing its contraceptive effectiveness in phase 2 clinical trials.
相似文献
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JE Robb LA Rymaszewski HB Bentley PT Donnan 《Surgical and radiologic anatomy : SRA》1991,13(3):181-185
Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.
La valeur du sourcil cotyloidien comme repère d'analyse radiologique
Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.相似文献
7.
Melissa R. Riester Elliott Bosco Barbara H. Bardenheier Patience Moyo Rosa R. Baier Melissa Eliot Joe B. Silva Stefan Gravenstein Robertus van Aalst Ayman Chit Matthew M. Loiacono Andrew R. Zullo 《Journal of the American Medical Directors Association》2021,22(6):1271-1278.e3
ObjectivesQuantify how observable characteristics contribute to influenza vaccination disparities among White, Black, and Hispanic nursing home (NH) residents.DesignRetrospective cohort.Setting and ParticipantsShort- and long-stay U.S. NH residents aged ≥65 years.MethodsWe linked Minimum Data Set (MDS) and Medicare data to LTCFocUS and other facility data. We included residents with 6-month continuous enrollment in Medicare and an MDS assessment between October 1, 2013, and March 31, 2014. Residents were classified as short-stay (<100 days in NH) or long-stay (≥100 days in NH). We fit multivariable logistic regression models to assess the relationships between 27 resident and NH-level characteristics and receipt of influenza vaccination. Using nonlinear Oaxaca-Blinder decomposition, we decomposed the disparity in influenza vaccination between White versus Black and White versus Hispanic NH residents. Analyses were repeated separately for short- and long-stay residents.ResultsOur study included 630,373 short-stay and 1,029,593 long-stay residents. Proportions vaccinated against influenza included 67.2% of White, 55.1% of Black, and 54.5% of Hispanic individuals among short-stay residents and 84.2%, 76.7%, and 80.8%, respectively among long-stay residents. Across 4 comparisons, the crude disparity in influenza vaccination ranged from 3.4 to 12.7 percentage points. By equalizing 27 prespecified characteristics, these disparities could be reduced 37.7% to 59.2%. Living in a predominantly White facility and proxies for NH quality were important contributors across all analyses. Characteristics unmeasured in our data (eg, NH staff attitudes and beliefs) may have also contributed significantly to the disparity.Conclusions and ImplicationsThe racial/ethnic disparity in influenza vaccination was most dramatic among short-stay residents. Intervening on factors associated with NH quality would likely reduce these disparities; however, future qualitative research is essential to explore potential contributors that were unmeasured in our data and to understand the degree to which these factors contribute to the overall disparity in influenza vaccination. 相似文献
8.
Moyo SR Maeland JA Bevanger L 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1999,107(3):263-269
Surface-exposed proteins are important serotype markers in Streptococcus agalactiae (group B streptococci; GBS). The proteins include the c proteins c(alpha) and c(beta), the R4 protein and a protein provisionally called P. For all of these markers, protein-specific monoclonal antibodies (MAbs) have been generated. We have compared whole-cell-based fluorescent antibody testing (FAT), ELISA, and dot blotting for MAb-based detection of these proteins by testing a panel of 52 GBS isolates of different capsular antigen types. Of a total of 208 observations with each of the tests, positive signalling in the dot assay was observed in 32.2%, with ELISA in 27.8%, and with FAT in 26.4% of the recordings. Discordant results were noted most frequently with the c(beta) and c(alpha) MAbs. In the case of c(alpha) the reason for the discordant test results was further examined and it appeared that this could be attributed to low level expression of the c(alpha) protein, although structural variations of c(alpha) proteins cannot be excluded. Our findings favour dot blotting as the method of choice although we consider all three methods acceptable for serotyping of GBS. 相似文献
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10.
Saungweme T Khumalo H Mvundura E Moyo VM Gordeuk VR Rouault TA Gomo ZA Gangaidzo IT 《The Central African journal of medicine》1999,45(6):136-140
OBJECTIVES: To determine the concentrations of iron and alcohol in traditional beer, as well as how these may be related to the brewing process. DESIGN: Cross sectional study. SETTING/SUBJECTS: Rural communities living in four of Zimbabwe's nine provinces. MAIN OUTCOME MEASURES: Ionic iron concentration and alcohol concentration in 94 different types of alcoholic beverages prepared in rural areas, and 18 commercially produced beers. RESULTS: The commonest types of traditional beer were a seven day beverage called 'doro rematanda', a by-product of this seven day beer called 'muchaiwa,' and a one-day beverage called 'chikokiyana'. Methods of preparation were similar in the four provinces. Median (Q1, Q3) ionic iron concentrations were 52 (31 to 75) mg/L for the seven-day beer (n = 51), 24 (18 to 36) mg/L for muchaiwa (n = 30) and 21 (17 to 63) mg/L for chikokiyana (n = 13). In contrast, ionic iron concentrations in 12 samples of commercially prepared clear beers were 0.1 mg/L and in commercial opaque beer were 3.6 mg/L. Mean (SD) alcohol concentration in traditional beer was 4.1 g/100 ml (+/- 0.873) compared to 2.8 g/100 ml +/- 1.394) in the muchaiwa and 3.6 g/100 ml (+/- 1.445) in the one day brew, chikokiyana. Mean alcohol concentrations in the three commercial beers are reportedly 3.5 g/100 ml in the opaque beer (Scud), and 4.7 to 5.0 g/ml in clear beer (Zambezi and Castle lagers). CONCLUSIONS: Several preparation methods lead to traditional fermented beverages with very high iron concentrations. Measures to prevent dietary iron overload should include all of these beverages in their scope. 相似文献