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41.
When parental females (♀♀P = mothers) of the rotifer Notommata copeus are placed in light conditions inducing the appearance of mictic females in their offspring (F1), the age of the parents of these parental females significantly affects the ratio of mictic females in the F1 generation.

The preparental females (♀♀PP = grandmothers), the parental females and the F1 females are isolated in a medium changed at each generation and, in the second experimental series, changed daily: the preparental age effect implicates the transmission of substances on two generations.

This influence of the preparental age is rhythmic: the ratio of mictic females in F1 related to this age varies in a sinusoidal manner. This influence is endogenous: it persists, always in a sinusoidal form, when the medium in which each grandmother is placed is changed daily.

Furthermore, the net reproduction ratio, Ro, does not vary significantly with the preparental age during these experiments.  相似文献   
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BACKGROUND: Dietary trans fatty acids (dTFA) are primarily synthetic compounds that have been introduced only recently; little is known about their behavioral effects. dTFA inhibit production of omega-3 fatty acids, which experimentally have been shown to reduce aggression. Potential behavioral effects of dTFA merit investigation. We sought to determine whether dTFA are associated with aggression/irritability. METHODOLGY/PRINICPAL FINDINGS: We capitalized on baseline dietary and behavioral assessments in an existing clinical trial to analyze the relationship of dTFA to aggression. Of 1,018 broadly sampled baseline subjects, the 945 adult men and women who brought a completed dietary survey to their baseline visit are the target of this analysis. Subjects (seen 1999-2004) were not on lipid medications, and were without LDL-cholesterol extremes, diabetes, HIV, cancer or heart disease. Outcomes assessed adverse behaviors with impact on others: Overt Aggression Scale Modified-aggression subscale (primary behavioral endpoint); Life History of Aggression; Conflict Tactics Scale; and self-rated impatience and irritability. The association of dTFA to aggression was analyzed via regression and ordinal logit, unadjusted and adjusted for potential confounders (sex, age, education, alcohol, and smoking). Additional analyses stratified on sex, age, and ethnicity, and examined the prospective association. Greater dTFA were strongly significantly associated with greater aggression, with dTFA more consistently predictive than other assessed aggression predictors. The relationship was upheld with adjustment for confounders, was preserved across sex, age, and ethnicity strata, and held cross-sectionally and prospectively. CONCLUSIONS/SIGNIFICANCE: This study provides the first evidence linking dTFA with behavioral irritability and aggression. While confounding is always a concern in observational studies, factors including strength and consistency of association, biological gradient, temporality, and biological plausibility add weight to the prospect of a causal connection. Our results may have relevance to public policy determinations regarding dietary trans fats. Clinicaltrials.gov # NCT00330980.  相似文献   
44.

Background

Patients with ST-elevation myocardial infarction (STEMI) not treated with primary or rescue percutaneous coronary intervention (PCI) are at risk for recurrent ischemia, especially when viability in the infarct-area is present. Therefore, an invasive strategy with PCI of the infarct-related coronary artery in patients with viability would reduce the occurrence of a composite end point of death, reinfarction, or unstable angina (UA).

Methods

Patients admitted with an (sub)acute myocardial infarction, who were not treated by primary or rescue PCI, and who were stable during the first 48 hours after the acute event, were screened for the study. Eventually, we randomly assigned 216 patients with viability (demonstrated with low-dose dobutamine echocardiography) to an invasive or a conservative strategy. In the invasive strategy stenting of the infarct-related coronary artery was intended with abciximab as adjunct treatment. Seventy-five (75) patients without viability served as registry group. The primary endpoint was the composite of death from any cause, recurrent myocardial infarction (MI) and unstable angina at one year. As secondary endpoint the need for (repeat) revascularization procedures and anginal status were recorded.

Results

The primary combined endpoint of death, recurrent MI and unstable angina was 7.5% (8/106) in the invasive group and 17.3% (19/110) in the conservative group (Hazard ratio 0.42; 95% confidence interval [CI] 0.18-0.96; p = 0.032). During follow up revascularization-procedures were performed in 6.6% (7/106) in the invasive group and 31.8% (35/110) in the conservative group (Hazard ratio 0.18; 95% CI 0.13-0.43; p < 0.0001). A low rate of recurrent ischemia was found in the non-viable group (5.4%) in comparison to the viable-conservative group (14.5%). (Hazard-ratio 0.35; 95% CI 0.17-1.00; p = 0.051).

Conclusion

We demonstrated that after acute MI (treated with thrombolysis or without reperfusion therapy) patients with viability in the infarct-area benefit from a strategy of early in-hospital stenting of the infarct-related coronary artery. This treatment results in a long-term uneventful clinical course. The study confirmed the low risk of recurrent ischemia in patients without viability.

Trial registration

ClinicalTrials.gov: NCT00149591.  相似文献   
45.

Background

Phase angle (PhA) is derived from the resistance and reactance measurements obtained from bioelectric impedance analysis (BIA) and is considered indicative of cellular health and membrane integrity. This study measured PhA values of rehabilitation patients and compared them to reference values, measures of functional ability and serum C-reactive protein (CRP) levels to explore their utility as a clinical tool to monitor disease progression and treatment efficacy.

Methods

This cross-sectional observational study was conducted on 215 ambulatory rehabilitation patients aged 20 – 94 years. All participants had been hospitalised for a stroke, orthopaedic or other condition resulting in a functional limitation. PhA was derived from BIA analysis and functional ability characterised using the Functional Independence Measure (FIM), timed up and go (TUG) and maximal quadriceps strength (MQS). Serum levels of CRP were also collected.

Results

Stroke patients had the highest PhA (5.3°) followed by elective orthopaedic surgery (5.0°) with the other group (4.3°) significantly lower than both previous categories (p < 0.001). Ambulatory rehabilitation patients' PhA values were dependent on age and sex (p < 0.001), lower than published age matched healthy reference values (p ≤ 0.05) and similar to other hospitalised or sick groups, but also higher than values reported in critically ill patients. Patients with CRP values less than 10 mg.L-1 had significantly (p = 0.005) higher mean PhA values. Furthermore, the highest functional status quartiles had significantly higher PhAs (p ≤ 0.04) for the FIM, MQS and TUG measures.

Conclusion

The results suggest that the phase angles of rehabilitation patients are between those of healthy individuals and seriously ill patients, thereby supporting claims that PhA is indicative of general health status. Phase angles are a potentially useful indicator of functional status in patients commencing an ambulatory rehabilitation program with a normal hydration status.
  相似文献   
46.
Greenbug, Schizaphis graminum (Rondani) (Hemiptera: Aphididae), was first discovered damaging seashore paspalum (Paspalum vaginatum Swartz) turfgrass in November 2003 at Belle Glade, FL. Inquiries to several golf courses with seashore paspalum turf across southern Florida indicated infestation was wide spread by April 2004. Damage symptoms progress from water soaked lesions surrounding feeding sites within 24 h to chlorosis and necrosis of leaf tips within 96 h. Problems caused by greenbug feeding were initially misdiagnosed as fertilizer, disease, other insects, or water management problems because aphids were not previously found on warm season turfgrasses. Greenbug development and fecundity studies were conducted on six seashore paspalum varieties: 'Aloha,' 'SeaDwarf,' 'SeaGreen,' 'SeaIsle,' 'SeaWay,' and 'SeaWolf.' Greenbug did not survive on 'SeaWolf.' Development rates (mean +/- SEM) ranged from 7.6 +/- 0.2 to 8.2 +/- 0.2 d on the remaining varieties. Greenbug longevity and fecundity on 'Aloha' were significantly less than on the other varieties. The estimated intrinsic rate of natural increase (r(m)) for greenbug ranged from 0.24 to 0.26 across tested varieties. Values for net reproductive rate (R(o)) ranged from 12.3 on 'Aloha' to 40.4 on 'SeaWay.' In feeding trials on indicator plants, the Florida isolate of greenbug exhibited a unique biotypic profile most commonly found on noncultivated grass hosts. It was virulent on the wheat variety GRS1201 that is resistant to the principal agricultural biotypes attacking small grains and to all currently available resistant sorghum varieties.  相似文献   
47.
Summary To establish an immortalized lacrimal gland epithelial cell line, the orbital lacrimal glands of normal New Zealand White rabbits were multiply injected with an immortalizing amphotropic retroviral vector (LXSN16E6E7) containing the E6 and E7 genes of human papillomavirus type 16. Lacrimal glands were removed after 2 d and acinar epithelial cells were isolated and cultured on Matrigel-coated 60 mm2 plates containing DMEM-F12 supplemented with 5% Nu-serum V. Transformed cells were selected in G418 sulfate for 7 d and passaged. Morphology of the immortalized cells was similar to that described for normal acinar cells both in vivo and in vitro, with rough endoplasmic reticulum and secretory granules. These characteristics remained unchanged and the cells continued to exhibit typical polygonal epithelioid structure. The cells have been maintained in culture for 14 mo. and have gone through 58 passages without loss of proliferation or epithelial cell characteristics. Immunohistochemistry and Western blots showed positive reactivity to secretory component, transferrin, and transferrin receptor, which are typical proteins found in the lacrimal gland. Functional analysis by stimulation with a cholinergic agonist, carbachol (100 μM), resulted in a significant release of protein. This is the first report of an immortalized rabbit lacrimal epithelial cell. These cells will provide a valuable tool for the molecular analysis of lacrimal gland epithelial cell functions.  相似文献   
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The Gravlee endometrial jet wash technique has been used to collect uterine fluid in normal human volunteers for Prostaglandin F analysis throughout the human menstrual cycle. Uterine washings so obtained demonstrated a cyclicity in prostaglandin F content with low concentrations found during the proliferative phase and a 3–4 fold rise occurring during the secretory phase. Menstrual fluid prostaglandin F content collected with the jet wash technique gave the highest total concentrations.  相似文献   
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