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排序方式: 共有1141条查询结果,搜索用时 62 毫秒
941.
H Siegel K Frei J Greenfield R Schiffmann S Sato 《Canadian Metallurgical Quarterly》1998,106(5):400-403
To evaluate their prognostic value, the expressions of CD44v and sialyl LeX (SLX) in colorectal cancers were studied immunohistochemically. Tissue specimens were reacted with monoclonal antibodies (mAb) CD44-1V and CSLEX-1. Of the 145 colorectal cancer patients undergoing curative resection, 59 (40.7%) were positive for mAb CD44-1V, and 40 (27.6%) were positive for mAb CSLEX-1. There was a significant correlation between the combined expression of SLX and CD44v8-10 and lymph node metastasis. The patients with tumors negative for CD44v8-10 and SLX had the most favorable prognoses. Conversely, the patients with tumors positive for both CD44v8-10 and SLX had a high recurrence rate and the poorest prognoses. In a multivariate analysis using the Cox regression model, the combined expression of SLX and CD44v8-10 emerged as an independent prognostic indicator. These results suggested that the combined expression of CD44v8-10 and SLX may be a biologic marker of prognostic significance. 相似文献
942.
OBJECTIVE: To clarify the definition of sexual abuse of boys, update estimates of its prevalence, and explore critically its reported correlates, sequelae, and management. DATA SOURCES: Studies from 1985 to 1997 were identified using OVID-MEDLINE and OVID-CINAHL. The search terms used were sexual abuse, sexual victimization, and sexual assault. Constraints applied included English language, human male subjects, age younger than 19 years, and North American samples. STUDY SELECTION: Publications were included for review if they appeared in peer-reviewed journals; had clear research designs; reported results for at least 20 male subjects; and were not reviews, perspectives, theoretical treatises, editorials, or letters. DATA EXTRACTION: Study types and sampling methods were categorized using well-established definitions. Preference was given to studies with large samples, with case-control or cohort designs, and/or with adjustment for effect modifiers or confounders. DATA SYNTHESIS: We identified 166 studies representing 149 sexual abuse samples. Studies were methodologically limited and definitions of sexual abuse varied widely. Prevalence estimates varied widely (by definition used and population studied), ranging from 4% to 76%. Boys at highest risk were younger than 13 years, nonwhite, of low socioeconomic status, and not living with their fathers. Perpetrators tended to be known but unrelated males. Abuse frequently occurred outside the home, involved penetration, and occurred more than once. Sequelae included psychological distress, substance abuse, and sexually related problems. Evaluation of management strategies was limited. CONCLUSIONS: Sexual abuse of boys appears to be common, underreported, underrecognized, and undertreated. Future study requires clearer definitions of abuse, improved sampling, more rigorous data collection, more sophisticated data analyses, and better assessment of management and treatment strategies. Regardless, health care professionals should be more aware of and sensitive to the possibility of sexual abuse in their male patients. 相似文献
943.
Zayed S. Abdullah Katherine J. Ficken Bethany P. J. Greenfield Tariq M. Butt 《Journal of chemical ecology》2014,40(6):534-540
Pollinophagy is widely documented in the order Thysanoptera, with representative individuals from six of the nine divergent families known to feed on pollen. Various pollens of the genus Pinus increase the development time, fecundity, longevity, and settling preference of Western Flower Thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Certain species of flower thrips discriminate among pollen types, but no studies have elucidated the olfactory cues that play a role in their pollen preferences. In this study, the volatile organic compounds emitted by pollens of the genus Pinus were elucidated. Various chemicals from pollen headspace elicited electrophysiological responses from WFT antennae. The compound (S)-(-)-verbenone, identified in pollen headspace, attracted WFT in a 4-arm olfactometer. This compound has potential for use in integrated pest management programs against the pest. We present the hypothesis that this polyphagous insect may have retained ancestral ‘relict’ olfactory receptors through the course of evolution, to explain this attraction to pine pollen. This attraction has allowed the insect to find and exploit an unusual nutrient source that significantly increases its fitness. The study demonstrates how fossil record analysis and subsequent evolutionary knowledge can aid in explaining possibilities as to why some insects sense and respond to chemicals that would otherwise seem peculiar to their ecology, allowing insight into the evolutionary forces that may shape insect olfactory systems over time. 相似文献
944.
DS Greenfield IJ Su?er MP Miller TA Kangas PF Palmberg HW Flynn 《Canadian Metallurgical Quarterly》1996,114(8):943-949
OBJECTIVE: To identify the incidence, causative organisms, and clinical outcomes of eyes with bleb-associated endophthalmitis after glaucoma filtering procedures with adjunctive mitomycin. METHODS: Retrospective analysis of 773 consecutive eyes that underwent glaucoma filtering surgery at the Bascom Palmer Eye Institute, Miami, Fla. The course of 609 eyes from 485 patients with a minimum of 3 months of follow-up were reviewed. RESULTS: Mean follow-up was 16.0 +/- 11.5 months (range, 3-48 months). Of the 609 eyes, 13 (2.1%) developed bleb-associated endophthalmitis an average of 18.5 +/- 13.2 months after surgery (range, 1-45 months). The incidence of bleb-associated endophthalmitis was significantly greater after inferior trabeculectomy (7.8% per patient-year) than after superior trabeculectomy (1.3% per patient-year) by Kaplan-Meier estimates (P = .02, log rank test). The cumulative incidence was 13% for inferior limbal blebs and 1.6% for superior limbal blebs. Nine (69.2%) of the 13 eyes were culture positive. Streptococcus sanguis and Haemophilus influenzae (6/13 [46.2%]) were the most frequent causative organisms. The mean increase in intraocular pressure after endophthalmitis treatment was 1.2 mm Hg, with a mean decrease in visual acuity of 1.42 logMAR units. Eight (61.5%) of the 13 eyes had a final acuity of 20/400 or better. CONCLUSIONS: The incidence of bleb-associated endophthalmitis after guarded filtering surgery performed with adjunctive mitomycin is higher than the reported rate in eyes undergoing filtering surgery without the use of antifibrotic agents (0.2%-1.5%). Inferior limbal trabeculectomy carries the highest risk of infection. Eyes with mitomycin blebs maintained excellent filtration capacity. However, after treatment of the infection, the visual outcomes were generally poor. 相似文献
945.
946.
The present study demonstrates that stereoselective binding sites for anandamide, a naturally occurring cannabinoid substance, can be found in invertebrate immunocytes and microglia. The anandamide-binding site is monophasic and of high affinity, exhibiting a Kd of 34.3 nM with a Bmax of 441 fmol/mg protein. These sites are highly selective, as demonstrated by the inability of other types of signaling molecules to displace [3H]anandamide. Furthermore, this binding site is coupled to nitric oxide release in the invertebrate tissues examined as well as in human monocytes. Interestingly, the cannabinoid-stimulated release of nitric oxide initiates cell rounding. Thus, these cannabinoid actions resemble those of opiate alkaloids. In this regard, we demonstrate that these signaling systems use the same effector system, i.e. nitric oxide release, but separate receptors. Last, the presence of a cannabinoid receptor in selected evolutionary diverse organisms indicates that this signaling system has been conserved for more than 500 million years. 相似文献
947.
Eighteen patients with bony defects of the mandible had the mandible reconstructed using conventional nonvascularized bone grafts from the iliac crest. After surgery they received radiotherapy for cancer in the oropharynx or oral cavity. This study was carried out over a 10-year period. All patients were followed-up both for their tumour growth and the results of their reconstruction. Four to 10 years after surgery 55.5 per cent were alive and well. Full dental rehabilitation was achieved in 33 percent and 12.5 percent were without dental rehabilitation. 相似文献
948.
Vpu is a small phosphorylated integral membrane protein encoded by the human immunodeficiency virus type 1 genome and found in the endoplasmic reticulum and Golgi membranes of infected cells. It has been linked to roles in virus particle budding and degradation of CD4 in the endoplasmic reticulum. However, the molecular mechanisms employed by Vpu in performance of these functions are unknown. Structural similarities between Vpu and the M2 protein of influenza A virus have raised the question of whether the two proteins are functionally analogous: M2 has been demonstrated to form cation-selective ion channels in phospholipid membranes. In this paper we provide evidence that Vpu, purified after expression in Escherichia coli, also forms ion channels in planar lipid bilayers. The channels are approximately five- to sixfold more permeable to sodium and potassium cations than to chloride or phosphate anions. A bacterial cross-feeding assay was used to demonstrate that Vpu can also form sodium-permeable channels in vivo in the E. coli plasma membrane. 相似文献
949.
Effect of substituting fresh‐cut perennial ryegrass with fresh‐cut white clover on bovine milk fatty acid profile 下载免费PDF全文
Sokratis Stergiadis Deborah N Hynes Anna L Thomson Kirsty E Kliem Carolina GB Berlitz Mevlüt Günal Tianhai Yan 《Journal of the science of food and agriculture》2018,98(10):3982-3993
BACKGROUND
Including forage legumes in dairy systems can help address increasing environmental/economic concerns about perennial ryegrass monoculture pastures. This work investigated the effect of substituting fresh‐cut grass with increasing quantities of fresh‐cut white clover (WC) on milk fatty acid (FA) profile and transfer efficiency of dietary linoleic (LA) and α‐linolenic (ALNA) acids to milk fat. Three groups of three crossbred dairy cows were used in a 3 × 3 crossover design. Dietary treatments were 0 g kg?1 WC + 600 g kg?1 grass, 200 g kg?1 WC + 400 g kg?1 grass, and 400 g kg?1 WC + 200 g kg?1 grass. All treatments were supplemented with 400 g kg?1 concentrates on a dry matter basis. Cows had a 19‐day adaptation period to the experimental diet before a 6‐day measurement period in individual tie stalls.RESULTS
Increasing dietary WC did not affect dry matter intake, milk yield or milk concentrations of fat, protein or lactose. Milk polyunsaturated FA concentrations (total n‐3, total n‐6, LA and ALNA) and transfer efficiency of LA and ALNA were increased with increasing dietary WC supply.CONCLUSION
Inclusion of WC in pastures may increase concentrations of nutritionally beneficial FA, without influencing milk yield and basic composition, but any implications on human health cannot be drawn. © 2018 The Authors. Journal of the Science of Food and Agriculture published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.950.
Forging friendship,soliciting support: A mixed-method examination of message boards for pregnant teens and teen mothers 总被引:1,自引:0,他引:1
Among pregnant youth, relationships with parents and romantic partners are correlated with overall wellbeing; however, this relationship does not exist with friends. Friends who have also experienced a pregnancy, however, may offer more effective support than friends who have not. One way that pregnant and mothering adolescents can connect is through online message boards. We hypothesized that adolescents would use these sites primarily to establish friendships and develop a supportive community, rather than simply to solicit pregnancy-related advice. We randomly selected 200 threads from four message boards for pregnant and mothering teens and performed a mixed-methods content analysis of the original posts and responses. Most original posts were categorized as “Community Oriented Posts,” rather than “Soliciting Pregnancy or Motherhood Advice.” Furthermore, qualitative analysis revealed frequent instances of emotional support, instrumental support, and informational support in both categories. In message board communities where pregnant teens and teen mothers were in the majority, messages were predominantly positive. In sharp contrast, in the one message board in which they were in the minority, as they are in the adolescent community at large, messages were significantly more negative. The dynamics of these message boards indicate the possibility that social support from other pregnant or mothering teens may enhance the wellbeing of pregnant teens and explain why peer “support” from teens who have not had this experience may often have a negative influence on wellbeing. 相似文献