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71.
We investigated the effect of arachidonic acid (AA) on the release of [3H]acetylcholine ([3H]ACh) from the rat hippocampus. AA (3-30 microM) increased the basal tritium outflow and the field-electrically evoked release of [3H]ACh from hippocampal slices in a concentration-dependent manner. AA (30 microM) produced a 69+/-7% facilitation of the evoked and a 36+/-3% facilitation of basal tritium outflow. The effect of AA (30 microM) on the evoked tritium release was prevented by bovine serum albumin (BSA, 1%), which quenches AA, and was unaffected by the cyclooxygenase inhibitor, indomethacin (100 microM), and the lipooxygenase inhibitor, nordihydroguaiaretic acid (50 microM). Phospholipase A2 (PLA2, 2 U/ml), an enzyme that releases AA from the sn-2 position of phospholipids, mimicked the facilitatory effect of AA on the evoked tritium release (86+/-14% facilitation), an effect prevented by BSA (1%). The PLA2 activator, melittin (1 microM), enhanced the evoked tritium release by 98+/-11%, an effect prevented by the PLA2 inhibitor, arachidonyl trifluromethylketone (AACOCF3, 20 microM), and by BSA (1%). AA (30 microM), but not arachidic acid (30 microM), also facilitated (72+/-9%) the veratridine (10 microM)-evoked [3H]ACh release from superfused hippocampal synaptosomes, whereas PLA2 (2 U/ml) and melittin (1 microM) caused a lower facilitation (46+/-1% and 38+/-5%, respectively). The present results show that both exogenously added and endogenously produced AA increase the evoked release of [3H]ACh from rat hippocampal nerve terminals. Since muscarinic activation triggers AA production and we now observed that AA enhances ACh release, it is proposed that AA may act as a facilitatory retrograde messenger in hippocampal cholinergic muscarinic transmission as it has been proposed to act in glutamatergic transmission.  相似文献   
72.
PURPOSE: We aimed with study to assess the current clinical practice about the management of high blood pressure in patients in the acute phase of ischemic stroke. We also comment some topics of ischemic stroke treatment. METHODS: A case report of a patient admitted 8 hours after onset of ischemic stroke and with blood pressure of 186 x 110 mmHg was presented to 120 surgeons and clinician. They were asked to decide the best therapeutic option: to increase, decrease or maintenance blood pressure. RESULTS: Thirty-eight physicians (31.7%) considered decreasing blood pressure the best therapeutics, 82 (68.3%) considered maintenance and none decided to increase it (p < 0.05). There was no difference between the two specialties conduct. The physicians, with more than 10 years of graduation, had a tendency to decrease the blood pressure (p < 0.05). CONCLUSION: The maintenance of blood pressure may present a sufficient blood support to compensate brain flow. A high percentage of the physicians (31.7%) do not know about the current concepts of therapeutics considering hypertension in acute ischemic stroke. The development on special units to treat these patients ("stroke units") may eventually decrease the morbimortality rates of ischemic stroke.  相似文献   
73.
Severity of a case is one of the ingredients in management systems. Severity adjustment systems have limitations, and confusion and diversity characterize definitions of severity of a case. These facts may be a consequence of lack of conceptual knowledge. Based on a holistic theory of health, we introduce a definition of severity of a case from a patient perspective. Here severity is characterized as having two basic components: disease severity and illness severity; and five dimensions: suffering, disabilities, risk of suffering, risk of disabilities and risk of death. A classification of instruments as measures of severity dimensions is presented. This classification is based on definition and application criteria. The article's main contribution is to combine theoretical and practical knowledge about severity of a case, which may empower implementations of outcome management systems in health care.  相似文献   
74.
We investigated whether chronic stress, applied from prepuberty to early puberty, interferes with the spermatogenic and androgenic testicular functions. Male pubertal rats (40 days old) were immobilized 6 h per day for 15 days. Plasma concentrations of corticosterone, prolactin and testosterone were significantly augmented following immobilization, whereas plasma luteinizing hormone decreased and follicle-stimulating hormone was not altered. Acute immobilization (5 min) increased prolactin and testosterone levels in control rats but caused a significantly higher increase in these hormones when superimposed on chronic stress. A lower extent of testicular maturation was observed in pubertal rats immobilized from prepuberty.  相似文献   
75.
Lack of apoptosis has been linked to prolonged survival of malignant B cells expressing bcl-2. The aim of the present study was to analyze the amount of bcl-2 protein expressed along normal human B-cell maturation and to establish the frequency of aberrant bcl-2 expression in B-cell malignancies. In normal bone marrow (n=11), bcl-2 expression obtained by quantitative multiparametric flow cytometry was highly variable: very low in both CD34(+) and CD34(-) B-cell precursors, high in mature B-lymphocytes and very high in plasma cells. Bcl-2 expression of mature B-lymphocytes from peripheral blood (n=10), spleen (n=8) and lymph node (n=5) was significantly higher (P<0.02) in CD23(-) as compared to CD23(+) B cells, independent of the type of tissue analyzed. Upon comparison with normal human B-cell maturation, bcl-2 expression in neoplastic B cells from 144 patients was found to be aberrant in 66% of the cases, usually corresponding to bcl-2 overexpression (63%). Follicular lymphoma (FL) carrying t(14;18) and MALT lymphoma were the only diagnostic groups constantly showing overexpression of bcl-2. Bcl-2 overexpression was also frequently found in precursor B-acute lymphoblastic leukemia (84%), typical (77%) and atypical (75%) B-cell chronic lymphocytic leukemia, prolymphocytic leukemia (two of three cases), mantle cell lymphoma (55%), but not in t(14;18)(-) FL, splenic marginal zone lymphoma, Burkitt lymphoma and multiple myeloma.  相似文献   
76.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph.  相似文献   
77.
This report describes the consequences and some aspects of the origin and development of victim blaming in accident analysis, and some methods for investigating such events, with particular emphasis on the situation in Brazil. In Brazil, the spread of this practice seems to have been helped by several factors. (1) The idea that occupational accidents are simple phenomena with a limited number of causal factors linked to unsafe actions and/or conditions. In the past, the theory of accident proneness had less influence than in other countries. (2) Government regulations that stipulate the hiring of health and safety officers, production of "educational" material, and "preventive" campaigns that emphasize the role of the victim's "faulty" behavior in the origin of an accident. (3) Mandatory implementation of standardized models for accident investigation directed toward searching for a single "cause." Usually one conclusion, expressed in terms of unsafe acts or conditions, is formulated so that whoever performs an unsafe act is responsible for the accident. (4) Lack of knowledge, as shown in Brazilian publications on occupational accidents and in the evolution of studies on the nature of accident phenomena and of strategies adopted for their prevention.  相似文献   
78.
We have developed a non-invasive method utilizing feces, containing sloughed colonocytes, as a sensitive technique for detecting diagnostic colonic biomarkers. In this study, we used the rat colon carcinogenesis model to determine if changes in fecal protein kinase C (PKC) expression have predictive value in monitoring the neoplastic process. Weanling rats were injected with saline or azoxymethane (AOM) and 36 weeks later fecal samples and mucosa were collected, poly A+ RNA isolated, and quantitative RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and zeta mRNA levels were altered by the presence of a tumor, with tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII expression as compared with animals without tumors. In addition, AOM-injection increased mucosal PKC betaII mRNA expression compared with saline controls. No effect of tumor incidence on mucosal PKC betaII expression was observed. In contrast, fecal PKC zeta expression was 2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus saline. Since tumor incidence exerts a reciprocal effect on fecal PKC betaII and zeta mRNA expression, data were also expressed as the ratio between PKC betaII and zeta. The isozyme ratio was strongly related to tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25, animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that the expression of fecal PKC betaII and zeta may serve as a noninvasive marker for development of colon tumors. A sensitive technique for the detection of colon cancer is of importance since early diagnosis can substantially reduce mortality.   相似文献   
79.
80.
Aim The Pro Children consortium consists of the following partners: Knut-Inge Klepp (Coordinator), Department of Nutrition, University of Oslo, Norway; Carmen Perez Rodrigo, Unidad de Nutricion Comunitaria, Bilbao, Spain; Inga Thorsdottir, Unit for Nutrition Research, Landspitali University Hospital, Reykjavik, Iceland; Pernille Due, Department of Social Medicine, University of Copenhagen, Denmark; Maria Daniel Vaz de Almeida, Faculdade de Ciências da Nutrição e Alimentação da Universidade do Porto, Portugal; Ibrahim Elmadfa and Alexandra Wolf, Institute of Nutrition, University of Vienna, Austria; Jóhanna Haraldsdóttir, Research Department of Human Nutrition, Royal Veterinary and Agricultural University, Copenhagen, Denmark; Johannes Brug, Erasmus Medical Center Rotterdam, Department of Public Health, The Netherlands; Michael Sjöström and Agneta Yngve, Unit for Preventive Nutrition, Karolinska Institutet, Stockholm, Sweden; Ilse De Bourdeaudhuij, Department of Movement and Sport Sciences, Ghent University, Belgium.The Pro Children study is designed to assess vegetable and fruit consumption and determinants of the consumption patterns among European school children and their parents. A second objective is to develop and test strategies for promoting increased consumption of vegetables and fruits among school children and their parents.Subjects and methods Surveys of national, representative samples of 11-year-old school children and their parents were conducted in nine countries during October–November 2003, i.e. in Austria, Belgium, Denmark, Iceland, The Netherlands, Norway, Portugal, Spain and Sweden. Comprehensive school-based educational programmes were developed and tested in three settings, i.e. in the Bilbao region, Spain, in Rotterdam, The Netherlands, and in Buskerud county of Norway. A 24-h recall format and frequency items assessing regular intake were used to assess vegetable and fruit consumption. Determinants were assessed employing the theoretical framework of the ASE model (Attitudes, Social Influences and Self-Efficacy), including cognitive factors, normative influences, skills and environmental barriers related to vegetable and fruit consumption. The intervention programmes were tested employing a group-randomized trial design where schools were randomly allocated to an intervention arm and a delayed intervention arm. Surveys among all participating children and their parents were conducted prior to the initiation of the intervention (September 2003; month 0), immediately after the end of the intervention (at month 8) and at the end of the subsequent school year (month 20).Results Preliminary data from the project indicate that girls eat vegetables and fruit significantly more often than do boys across all participating countries. There are no sex differences, however, with respect to perceived availability of vegetables and fruit at home and outside the home setting. In all countries, perceived availability appears to be significantly associated with reported frequency of both vegetable and fruit consumption.Conclusion Experience so far indicates that the Pro Children Project will succeed in producing valid and reliable research instruments for assessing vegetable and fruit consumption among school children and their parents and that comparable, comprehensive intervention programmes can be implemented across geographic and cultural settings within Europe.  相似文献   
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