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Increasing industrial activity in the European Arctic has raised concerns of the potential anthropogenic impact of chemicals on this polar marine ecosystem. For the past 20 years or so, biomarkers have been developed to provide early-warning signals of detrimental impacts of chemicals on the marine ecosystem, however, most biomarker methods have been established for organisms living in temperate rather than polar waters. Little is known about biomarker responses in organisms living within the temperature range of -1.88 to +5 degrees C. In this study, established biomarkers from temperate studies were tested on the Arctic spider crab Hyas araneus to validate their use in polar ecosystems. H. araneus is common in Svalbard fjord (Norway), although it is a temperate water species occurring from northern Spain to Svalbard at depths from 10 to 1200 m. In this paper, the effects of oil were investigated at 2 degrees C via two routes: (i) injection and (ii) contaminated sediment. After 2 weeks of exposure, heart rate, oxygen consumption and total oxyradical scavenging capacity (TOSC) were measured in the same individuals. In both methods of contaminant exposure, heart rate showed a significant increase compared with the control (P < 0.0001, n = 7); mean heart rate values (+/- S.D.) of H. araneus were 49.06 (+/- 13.72), 57.56 (+/- 7.28) and 63.30 (+/- 6.57) beats per minute in control, injected and sediment-treated groups, respectively. Respiration of H. araneus was not affected significantly by either oil treatment (P > 0.05), but two individuals (n = 8) showed a marked increase in oxygen uptake in the sediment-exposed group. The basal oxygen consumption of control H. araneus was lower (0.025 mg O(2) g wet wt.(-1) h(-1)) than reported for H. araneus living in temperate water. Although TOSC of H. araneus was not affected significantly by either exposure treatment (P > 0.05) the mean TOSC value in the sediment-exposed group was lower than the control, indicating some saturation of the oxyradical scavenging system. Results indicate that although low temperature appears to be the main factor reducing the bioavailability of polycyclic-aromatic hydrocarbons, the relatively low metabolic rate of Arctic H. araneus is also implicated in decreased uptake and metabolism of oil compounds into reactive oxygen species (ROS).  相似文献   
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Objective: To test the effect of changing referral mode to Consultation–Liaison Psychiatry (C–L Psychiatry) by implementing early screening with systematic multidisciplinary management for emotional disorders in noncognitively impaired medical inpatients. Method: A prospective pre- and postintervention controlled study in the internal medicine division of a university hospital. Results: Out of 515 patients admitted to the internal medicine ward during the study period, 176 were included in the study and gave their informed consent (male=63%); 81 in the control group and 95 in the intervention group. Except for the increase in referral rate to the C–L Psychiatry service (4–32%), there were no significant differences between the baseline and intervention periods either in terms of length of stay in the internal medicine ward and of use and costs of medical resources, or in terms of patients' satisfaction as regards attention paid to psychosocial issues during hospitalization. Conclusion: As a result of changing referral mode to C–L Psychiatry, the lack of effect on length of stay and on medical consumption of medically ill inpatients should be considered in the context of the briefness of the hospitalization periods encountered. Furthermore, the change in referral process does not seem to increase patients' perception of the quality of care provided.  相似文献   
44.
OBJECTIVE: Our aim was to determine whether chorionicity in twin gestations can be diagnosed by use of high-frequency ultrasonography to count the layers of intraamniotic membrane. STUDY DESIGN: This prospective study of 66 twin pregnancies between 13 and 38 weeks' gestation used transabdominal ultrasonography at 10 MHz. The pregnancy was classified as monochorionic when two layers were counted and as dichorionic when three or four layers were counted. The findings of the examiner, who had no other information about chorionicity, were compared with those of the histopathologic examination of the placenta. RESULTS: Ultrasonography allowed chorionicity to be determined correctly in 60 of 63 cases (95%; 100% in the second trimester and 92% in the third). The predictive value for dichorionicity was 100% (48/48) and the sensitivity 94% (48/51). The 12 monochorionic diamniotic pregnancies in which the membrane was visualized were all correctly diagnosed. In a thirteenth case, with severe oligohydramnios, the membrane could not be seen. Two patients were lost to follow-up. In 95% of the cases (63/66) only one examination was required to diagnose chorionicity. Intraobserver variability was 0% (0/26). Interobserver variability, tested by photographs, was 3% (2/65). CONCLUSIONS: This technique should be the first-line method for determining chorionicity in the second and third trimesters because it is the most effective. Its excellent reproducibility may be attributable to the use of high-frequency ultrasonography. (Am J Obstet Gynecol 1996;175:1529-33.)  相似文献   
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The purpose of this study was to report on a 10-year experience in the treatment of subfertile women with intrauterine adhesions using the resectoscope or the Versapoint system. Forty-six subfertile women with stage I (n = 6), stage II (n = 25) and stage III (n = 15) intrauterine adhesions underwent adhesiolysis with the use of the resectoscope (n = 21) or the Versapoint system (n = 26). Synechiolysis was successful in 43 women (93.5%) after the first attempt. In 13 out of 14 women (92.9%) with oligo/amenorrhoea at presentation, restoration of menses was reported after adhesiolysis (Versapoint: 9/9, resectoscope: 4/5). Overall live delivery rates according to stage of intrauterine adhesions were 33.3, 44.4 and 46.7% for stages I, II and III respectively. Similar cumulative delivery rates were achieved in patients with no additional infertility factors who attempted to conceive naturally after adhesiolysis using the Versapoint (71.7%) or the resectoscope (60%). Ten gestations ended in preterm delivery (50%), while in two of the women who delivered, a hysterectomy was performed due to placenta accreta. In conclusion, hysteroscopic adhesiolysis offers a real chance of parenthood in a substantial proportion of infertile couples either by using the Versapoint system or the resectoscope.  相似文献   
48.
Geriatric depression and vascular diseases: what are the links?   总被引:5,自引:0,他引:5  
BACKGROUND: The term "vascular depression" has been proposed to describe a subset of depressive disorders that occurs in old age as a consequence of cerebrovascular disease. However, depression has been shown to result from other cardiovascular diseases such as coronary heart diseases, as well as to precipitate, worsen or precede vascular diseases. Depression also increases the likelihood of the incidence of vascular risk factors such as diabetes. AIMS: To review clinical and epidemiological evidence linking geriatric depression and vascular diseases, and to discuss the potential mechanisms that could underlie this association. METHOD: Systematic review of the literature of the last 5 years through Medline database search. RESULTS: Papers report the following potential ways of association: (1) there is a direct influence of vascular disease, in particular, arteriosclerosis, on the incidence of depression; (2) depressive disorders have a direct impact on the cardiovascular system; (3) depression and vascular disease share either a common pathophysiological process or genetic determinants. DISCUSSION: Depression can be understood as the direct consequence of brain damage in neurodegenerative disorders such as Parkinson's or Huntington's diseases. Similarly, vascular depression is mostly considered to be the consequence of microvascular lesions on prefrontal and subcortical regions. However, this functional neuroanatomical model offers no explanation for cases where depression has been shown to precede vascular diseases. Since cardiovascular diseases develop in a context of acquired environmental factors together with genetically determined disease, it may be postulated that geriatric depression could both result from brain lesions of vascular origin and also share some pathogenic or genetic determinants.  相似文献   
49.
The present study was conducted to further examine recent data suggesting that pneumocystosis could be transmitted between patients and healthcare workers in the hospital environment, as has been proven with Pneumocystis-infected SCID mice and immunocompetent Balb/c mice. Using an experimental design (i.e., SCID–Balb/c mouse airborne transmission system), the present work found that healthy host-to-healthy host transmission of Pneumocystis organisms can occur, and that second healthy contacts are able to transmit the infectious organisms to immunocompromised hosts. Further tests designed to explore the behavior of Pneumocystis organisms in the lungs of immunocompetent hosts were performed using histological and molecular approaches (e.g. testing the expression of both cyclin-dependent serine-threonine kinase and heat-shock 70 protein in Pneumocystis). The results showed Pneumocystis organisms were able to replicate in the lungs of immunocompetent hosts, which indicates these hosts are a reservoir for Pneumocystis spp.  相似文献   
50.
The aim of this study was to investigate how the cognitive tuning of corticospinal (CS) excitability adapts to the type of evoked-movement (Flexion vs. Extension) during human gait. Transcranial magnetic stimulation (TMS) was used both as a central perturbation evoking a movement and as a tool for quantifying the CS excitability of the muscles under study (RF/BF). In the first condition (Dst), the TMS occurred at mid-stance, inducing hip extension, whereas in the second condition (Dsw), the TMS occurred at the beginning of the swing phase, inducing hip flexion. In both conditions, the subjects were asked to cognitively prepare to either not intervene (NINT) or to compensate (COMP) for the evoked-movements. The results showed that, regardless of the type of evoked-movement, preparing to compensate resulted in a selective increase in the CS excitability to those muscles that would be involved in counteracting the possible central perturbation, i.e. the hip extensor muscle (BF) to compensate for an evoked flexion during the swing phase or the hip flexor muscle (RF) to compensate for an evoked extension during the stance phase. This latter result offers the first evidence of a modulation in CS excitability to the proximal muscles during the stance phase. In conclusion, the cognitive tuning of CS excitability was found to adapt to the gait phases. Moreover, the same selective preparation strategy was observed whether the central perturbation occurred during the stance or the swing phase of the step cycle.  相似文献   
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