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81.
Background: Epiretinal membranes from eyes with proliferative vitreoretinopathy (PVR) frequently express molecules associated with chronic inflammation. To investigate the extent to which inflammation may compromise the detached retina, we determined the expression of inflammatory molecules in anterior retina removed after relaxing retinotomy for retinal detachment complicated by anterior PVR. Methods: Surgical retinal specimens were studied immunohistochemically for the distribution of the vascular cell adhesion molecules VCAM, E-selectin, P-selectin, ICAM and PECAM and for the presence of the cytokine TNF and of T lymphocytes (CD3-positive cells), macrophages (CD68-positive cells) and HLA-DR molecules. The findings were compared with those in control cadaveric retina. Results: Aberrant expresion of ICAM-1 was observed in four of nine retinal specimens from eyes with PVR, whereas its expression in control retinas was confined to the external limiting membrane and ganglion cell layers. PECAM was observed in seven of nine surgical retinal specimens and in four of five controls. E-selectin and P-selectin were expressed within the luminal aspects of four of nine retinal specimens from eyes with PVR, and VCAM was present in three of nine surgical specimens investigated. All cadaveric control retinas were negative for E-selectin and VCAM, whilst one was positive for P-selectin. Staining for TNF was observed within luminal aspects and walls of retinal vessels from eight of nine surgical specimens, but was not seen in any of the cadaveric controls. T lymphocytes and cells expressing the macrophage marker CD68 were identified in two and seven of nine diseased retinas respectively, but not in any of the controls. Cells staining for HLA-DR were observed in eight of nine surgical retinal specimens and in three of five controls. Conclusion: The present findings indicate that retina from eyes with advanced PVR may itself be subject to inflammatory changes, and indicate that the PVR process is not limited to retinal membranes, but involves a more widespread distribution of inflammation than is generally appreciated.  相似文献   
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The present paper aims to explore issues related to men within the context of seeking help for substance abuse. The male gender role is in conflict with help-seeking behaviour and with the fundamental principles of therapy, i.e. introspection, emotional expressivity and acknowledgement of difficulties. This creates a paradox for the male seeking psychological treatment and, it will be argued, particularly for the male substance abuser. It is argued that interventions which address the gender role and challenge men's perceptions of themselves are critical variables in the outcome of therapy, i.e. enabling them to make the necessary changes in order to promote psychological well-being. An examination of the male gender role in relation to intrapsychic issues and family systems will be followed by a brief discussion of therapeutic interventions. Some of the difficulties and issues confronted by workers who work with male substance abusers will be explored.  相似文献   
85.
A series of experiments examined the effects of 6-hydroxydopamine (6-OHDA)-induced depletion of forebrain norepinephrine (NE) on the performance of a visual detection (spatial localization) task. The behavioral paradigm used was an analogue of Leonard's 5-choice serial reaction time task for humans. The 6-OHDA lesion of the dorsal noradrenergic bundle (DNAB) produced a 98% depletion of the NE content in the neocortex, and a much smaller depletion (32%) of the NE content in the hypothalamus. As reported previously, performance of visual discrimination was unaffected by DNAB lesions, even when the discrimination was made more difficult by decreasing the intensity of the visual stimuli. However, the lesion produced a significant decrease in accuracy and a significant increase in omissions when a burst of loud white noise was presented just prior to the onset of the visual discriminanda. Similarly, a significant decrease in discriminative accuracy was produced in the rats with forebrain NE depletion by systemic administration of the psychomotor stimulant, d-amphetamine (0.2 to 0.8 mg/kg). In both of these experiments, the lesion-induced discrimination impairment was not magnified by reducing the brightness of the visual discriminanda, suggesting that the behavioral impairment was not caused by a decreased ability to detect the visual stimuli. In addition, the lesion impaired discriminative accuracy when the visual discriminanda were presented at an unpredictable rate. The implications of these behavioral impairments produced by forebrain NE depletion for theories of catecholamine involvement in attentional processes and arousal are discussed in terms of a possible role for the DNAB in controlled or "effortful" processing.  相似文献   
86.
One hundred and four preterm infants were studied during the first few months of life in the Special Care Baby Unit of Addenbrooke's Hospital, Cambridge, United Kingdom. Previously, it had been the daily practice within the Unit to give a 1 mg oral supplement of folate (in the form of pteroylglutamic acid), once the infants had commenced full enteral feeding. At least one blood sample was obtained from 70 infants before oral folate supplementation was started. In these, the plasma folate levels fell progressively from a median value of 45 g/l to a median of 12 g/l, by the 2nd–3rd week of life. Once started on the oral supplement, 83 of the infants provided at least one blood sample. The plasma folate level of these infants rose immediately to a median value of 300 g/l and a maximum of 1000 g/l. Within individuals, these plasma folate levels decreased progressively following the introduction of the supplement, despite continuing daily supplementation. In a typical baby this decrease appeared to be explained by an increase in body-size, i.e. dilution of the folate into a larger pool. The implications of this level of supplementation are discussed, and in the light of our observations we suggest that daily supplementation in the range, 0.05–0.2 mg folate may be preferable for well preterm infants.  相似文献   
87.
Citrobacter diversus brain abscess occurred in two infants in Aberdeen, 5 months apart. These are the first reported cases of this condition in the UK since 1976. Restriction endonuclease analysis with SacI enzyme showed blood and CSF isolates from both patients to be identical and different from 10 other clinical isolates of C. diversus and one C. amalonaticus strain. Furthermore, isolates of C. diversus from patients belonged to biotype "d" whereas control isolates were of biotypes "a" or "e". Because both infants attended the same central and peripheral maternity units, this raised suspicions of long term contamination of the hospital environment by this organism. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) patterns of whole-cell proteins and immunoblotting with normal human serum were remarkably homogeneous for all 13 C. diversus strains and thus were not useful for typing. However, the only C. amalonaticus strain was clearly differentiated from C. diversus strains by SDS-PAGE. Management of the infants included multiple intravenous antibiotic therapy for 4-6 weeks and repeated computerised tomography (CT) scanning and drainage of the abscess cavity. Both children survived albeit with some minor degree of brain damage.  相似文献   
88.
Serial EEGs have been carried out during the acute phase of haemorrhagic shock and encephalopathy syndrome (HS&E) in 22 infants and children aged 3 months to 14 years. Most patients presented with fits and coma and all had shock with bleeding and disseminated intravascular coagulation (DIC). The initial EEG showed prolonged runs of often rhythmic discharges which fluctuated in amount and amplitude with varying distribution and morphology ("electrical storms"). Over a period of days the "electrical storms" gradually decreased leaving only low amplitude EEG activities or evolving to electrocerebral silence (7 cases). Fifteen patients died and all five children with multifocal "electrical storms" who survived showed gross neurological handicap. The rather distinctive EEG pattern is unusual in the context of an acute encephalopathy outside the neonatal period although similar "electrical storms" may be seen in a less extreme form in infants and children with other conditions associated with DIC. This EEG pattern presumably reflects changes in the cerebral microcirculation which in HS&E are usually relentlessly progressive and associated with devastating cortical damage.  相似文献   
89.
The male contribution to contraceptive mismanagement and unwanted pregnancy was assessed among 109 students at the University of Melbourne in Australia. The survey was conducted 3 months prior to annual examinations. The interview focused on a range of subjects including socioeconomic data, extent of formal sex education, patterns of sexual behavior both in the past and in the present, contraception used within various types of relationships, reasons for contraceptive choice, and involvement in unwanted pregnancy. The age range of the subjects was 17-35. 84% (92) of the men had experienced heterosexual intercourse. 2 main types of relationships emerged: an emotionally committed and usually long-term relationship and a usually brief and "casual" relationship. 30% of all subjects thought that females should always be responsible for contraception. 31% believed that contraception was a joint responsibility in steady relationships but the female's responsibility in casual relationships. 35% of all subjects felt that both partners had an equal responsibility in preventing conception irrespective of the type of relationship. 4 men believed that contraception was always the male's responsibility. Contraceptive technique was rated adequate for 32% of the 92 sexually experienced men who always relied on either condoms, diaphragms, IUDs, oral contraceptives, or sterilization. Intermittent contraceptive use was reported by 60% of sexually experienced men who alternated betwen reliable and unreliable methods. Almost 1/5 of the sexually experienced men reported that they had been involved in an unwanted pregnancy.  相似文献   
90.
Self-administered, multiple-choice questionnaires were completed by 120 patients and students in order to assess their medical vocabulary knowledge. The fifteen test words were taken from printed health education materials. It was apparent that many respondents had problems with the words, in particular, those of low social status or low educational achievement. The scores of students, however, were not significantly higher than those of the patients. It is suggested that all health education materials be carefully screened for medical words, although they may have high readability scores. Even seemingly simple medical words should be explained in simple terms, or should be included in a glossary. This practice should increase understanding and recall.  相似文献   
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