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In this study we present the results of an intersex survey of Littorina littorea along the Belgian coast. Levels of female intersex and sterility were determined to assess TBT related adverse effects. In addition, we determined the levels of male penis shedding and trematode infestation and investigated the morphology of the shell. Significant differences were found for all these variables which clearly differentiated periwinkles from Zeebrugge (B2) from those at other locations. Intersex index (ISI) values were relatively low (i.e. 0.00-0.39), except at B2 where they ranged up to 3.52, the highest value ever reported in literature. Consequently, female reproductive impairment at B2 was severe. Indeed, up to 95% of female periwinkles were sterile at B2. In addition, 61% of the male periwinkles had shed their penis. Furthermore, no trematode infestation could be detected at B2 and specimens from this location had the largest and heaviest shells, which may be related to population demography and/or a different use of energy budgets.  相似文献   
23.
Radioprotection of mice by dietary squalene   总被引:1,自引:0,他引:1  
Male C3H mice were fed a diet containing 2% squalene for 14 d prior to and 30 d subsequent to exposure to 6, 7 or 8 Gy of whole body γ-irradiation (Cesium-137). After 14 d on squalene-supplemented diet, plasma and jejunal tissue squalene levels were 2X and 15X that of controls. Seven days after irradiation, total white cell counts and total lymphocyte counts were substantially depressed in a radiation dose-dependent manner. Although counts in the squalene group were consistently (18–119%) higher than those in the corresponding dietary control group, the differences between dietary groups at any single dose were not significant. Nuclear area of villus cells in the jejunum of both dietary groups was significantly reduced (20%) by day 11 post-irradiation but the nuclear area in squalene-fed mice was significantly greater (15%) than in controls, before and after irradiation. There were no differences in body weight as a function of either diet or radiation dose prior to the first observations of animal lethality. Animal survival was decreased from 100 to 0% at 30 d post-irradiation by radiation doses of 6–8 Gy, with the greatest difference between dietary groups being observed at 7 Gy (median survival times of 12 and 16 d for control and squalene groups, respectively). Overall, survival of squalene-fed mice was significantly prolonged compared with control-fed mice (P=0.0054 by censored multiple regression analysis). It is concluded that squalene conferred some cellular and systemic radioprotection to mice receiving these lethal whole-body radiation doses.  相似文献   
24.
Presently, enterococci take the third place of bacterial pathogens associated with nosocomial infections, after staphylococci and Escherichia coli. Especially, the resistances of enterococci to several available antibiotics are threatening. We attempted to determine which species of enterococci could be found in food of animal origin and their significance according to their antibiotic resistances for human beings. From November 2000 to May 2002 we investigated 155 samples of food of animal origin bought in retail outlets in Germany: 27 samples of sausages, 19 of ham, 83 of minced meat, 26 of cheese. From these food samples we isolated 416 enterococcal strains. The most frequent species was Enterococcus faecalis (299 strains); furthermore, we found Enterococcus faecium (54 strains), Enterococcus durans together with Enterococcus hirae (24 strains), Enterococcus casseliflavus (22 strains), Enterococcus avium (9 strains) and Enterococcus gallinarum (8 strains). We focused on the resistance patterns of 118 selected E. faecium and E. faecalis strains to 13 antimicrobial active agents (ampicillin, amoxicillin/clavulanic acid, avilamycin, chloramphenicol, enrofloxacin, erythromycin, flavomycin, gentamicin, penicillin, quinupristin/dalfopristin, teicoplanin, tetracycline and vancomycin). From the clinical point of view, the situation of antibiotic resistance to the examined antimicrobial agents seemed to be favourable. The investigated strains were sensitive to ampicillin and amoxicillin/clavulanic acid. These antibiotics are, in combination with an aminoglycoside, for example gentamicin, agents of choice for the treatment of enterococcal infections in human medicine. Only one E. faecium strain was resistant to penicillin, while all strains were sensitive to the glycopeptide antibiotics, vancomycin and teicoplanin. Resistances found against the antibiotics, tetracycline, quinupristin/dalfopristin and erythromycin, are causes for concern.  相似文献   
25.
Ample empirical research on values has demonstrated that clients' values tend to become increasingly like those of their therapist during therapy. There is little research, however, on how therapists negotiate value conflicts and the role of values in therapy. In order to better understand this process, 14 expert psychotherapists from four major psychotherapy orientations were interviewed about their use of values in the psychotherapeutic change process. A grounded theory analysis was conducted leading to an integrative understanding of how expert therapists from different orientations conceptualize the relationship of values and change in therapy and how they work with values in sessions. Based on this analysis, four transtheoretical principles were generated that can be applied to training and practice and used to inform research on psychotherapy process and integration. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
26.
The authors screened 194 university students to determine whether some could comprehend text well despite very poor recoding skills, measured by pseudoword reading. Most of the 17 poorest recoders had never been identified as reading disabled. We classified 6 poor recoders as "resilient readers" because their text comprehension scores were average or above, relative to the sample as a whole. They were indistinguishable from 6 matched typical readers on measures of text comprehension derived from oral-reading think-aloud protocols. There was no evidence that the resilient readers relied on superior verbal ability or working memory to compensate for poor recoding. The resilient readers were poor at spelling, reading isolated words, and reading text rapidly, but they showed adequate phonemic awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
27.
Adult facial expressions are more intense on the left hemiface, suggesting right hemisphere emotional specialization. In this research, adult judgments of mirror-image chimeras indicated that infant expressions are more intense on the right hemiface, which is not predicted by current models of adult cerebral asymmetries. The rightward bias was stronger when judgments were restricted to the central facial features in computer-digitized images of the chimeric faces. Because the mouth and eye regions receive contralateral versus bilateral cortical input, respectively, separate judgments of the mouth and eyes/brows were obtained. Only the mouths showed a significant rightward bias, implicating cortical rather than lower-level mechanisms. The results were replicated with a second set of infants. The findings are interpreted as support for a right-to-left gradient in development of cortical inhibition over subcortical influences on facial expressions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
28.
As the number of genes associated with inherited disease continues to grow, researchers and practitioners in behavioral medicine will encounter complex psychological issues faced by individuals at risk for these diseases. A review of the literature concerning prenatal, carrier, and predictive genetic testing suggests that the severity of psychological risks posed by research-based genetic testing is not great. However, subgroups of individuals with particular psychological traits may be more vulnerable to adverse effects. Available data do not provide evidence that genetic testing promotes changes in health-related behaviors. Thus, although there may be less of a role for mental health professionals in the psychological counseling of genetic testing participants, there is a need for research and practice to facilitate health protective behaviors in response to genetic risk information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
29.
The natural lignan hydroxymatairesinol was hydrogenolysed to a potential anticarcinogenic substance matairesinol over different carbon-supported palladium catalysts. The reaction was conducted in 2-propanol at 70 °C under hydrogen flow in a stirred glass reactor. The catalysts were characterised by N2-physisorption, CO pulse chemisorption and pH measurement of aqueous catalyst slurries. The most active catalyst (Degussa-Hüls) gave yields of matairesinol over 90% in 4 h. It was concluded that the acidity of the catalyst had a profound influence on the reaction rate.  相似文献   
30.
A large proportion of patients who present for treatment of posttraumatic stress disorder (PTSD) experience comorbid panic attacks, yet currently available PTSD treatment programs do not address this problem. This report provides an initial evaluation of a newly developed treatment, multiple channel exposure therapy (M-CET), for comorbid PTSD and panic attacks. The treatment uses elements of cognitive processing therapy treatment for PTSD and elements of panic control treatment to target physiological, cognitive, and behavioral symptoms. Results suggest that M-CET may be a promising treatment program for a subset of PTSD patients who experience panic attacks. Preliminary guidelines for conducting M-CET in a group format with participants exposed to diverse traumatic events are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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