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81.
In view of the recent trend towards more minor surgery being carried out in general practice we decided to conduct a postal survey to assess the level of knowledge of sterilization and disinfection and the use of benchtop sterilizers in general practice in Northern Ireland. The survey, of all 366 practices in the Province, was carried out in January/March 1998. One hundred and eleven (30%) completed questionnaires were returned. All practices performed at least one of a range of procedures requiring sterilization or disinfection, e.g., minor surgery 95%, cervical smear taking 98%, syringing of ears 98%. Only 76% of practices had a benchtop sterilizer and 39% did not have access to a sterile supply department (SSD); 32% of the latter had no desire to utilize such a service. Only 25% and 34% correctly identified the Medical Devices Agency (MDA) definitions of sterilization and disinfection respectively. The MDA Device Bulletin on benchtop sterilizers had been read by only 26% of respondents. There was an 86% interest in attending a workshop on sterilization and disinfection. The concepts and practice of sterilization and disinfection appear not to be clearly understood. We conclude that resources must be identified to provide appropriate education in this important area for primary care staff.  相似文献   
82.
83.
  • 1 Autoradiographic binding studies have shown that the AT1 receptor is the predominant angiotensin II (AngII) receptor subtype in the central nervous system (CNS). Major sites of AT1 receptors are the lamina terminalis, hypothalamic paraventricular nucleus, the lateral parabrachial nucleus, rostral and caudal ventrolateral medulla, nucleus of the solitary tract and the intermediolateral cell column of the thoraco-lumbar spinal cord.
  • 2 While there are differences between species, AT2 receptors are found mainly in the cerebellum, inferior olive and locus coeruleus of the rat.
  • 3 Circulating AngII acts on AT1 receptors in the subfornical organ and organum vasculosum of the lamina terminalis (OVLT) to stimulate neurons that may have a role in initiating water drinking.
  • 4 Centrally administered AngII may act on AT1 receptors in the median preoptic nucleus and elsewhere to induce drinking, sodium appetite, a sympathetic vasoconstrictor response and vasopressin secretion.
  • 5 Recent evidence shows that centrally administered AT1 antagonists inhibit dipsogenic, natriuretic, pressor and vasopressin secretory responses to intracerebroventricular infusion of hypertonic saline. This suggests that an angiotensinergic neural pathway has a role in osmoregulatory responses.
  • 6 Central angiotensinergic pathways which include neural inputs to the rostral ventrolateral medulla may use AT1 receptors and play a role in the function of sympathetic pathways maintaining arterial pressure.
  相似文献   
84.
BACKGROUND: Studies of mortality from asthma and chronic obstructive pulmonary disease (COPD) have relied on death certification or registration for case finding. The aim of this study was to determine the accuracy of death certification and registration in asthma and COPD. METHODS: All death certificates in Northern Ireland for 1987 where asthma or COPD (defined as International Classification of Diseases 9th Revision (ICD9) 490, 491, 492, 496) were listed in part I or part II were identified. The following certificates were then selected for further investigation: those mentioning asthma for all ages, those mentioning COPD for ages less than 56 years, and a 50% sample of those mentioning COPD aged 56-75 years. For these selected deaths the general practitioners' case notes, hospital records, and necropsy findings were reviewed. Questionnaires detailing the clinical history and circumstances of death were completed by the general practitioner by post and by a close relative or associate of the deceased (doctor administered) if, after initial investigation, the death was likely to be due to COPD or asthma. A panel of two respiratory physicians reviewed each death and, using clinical diagnostic criteria, assessed the accuracy of the registered cause of death. RESULTS: Of 50 registered asthma deaths 43 were confirmed as being due to asthma. In nine registered deaths from COPD in cases aged less than 56 years one was confirmed as COPD, two as asthma, and six as other respiratory conditions. Of 105 registered deaths from COPD in cases aged 56-75, 42 were confirmed as COPD, 27 as asthma, eight as other respiratory conditions, and 28 as other causes. Although few errors in registration were found, 21% of certificates mentioning asthma and 38% of certificates mentioning COPD but not asthma in part I were subject to variable application of the classification rules by the registering officers. For all deaths under 75 years of age in Northern Ireland in 1987 where either asthma or COPD was mentioned anywhere on the death certificate, the estimated sensitivity and specificity of the registered cause of death in predicting the "true" cause of death were 29% and 98.6% for asthma and 69% and 70% for COPD. CONCLUSIONS: In a population of subjects where asthma or COPD was mentioned anywhere on the death certificate, the registered cause of death is a relatively poor indicator of the "true" cause of death for both asthma and COPD. Variation occurred in the application of death classification rules by registration officers. Many deaths certified and registered as COPD could have been called asthma using current standards of clinical diagnosis. In studies investigating risk factors for deaths from asthma, case finding should consider deaths registered as COPD.  相似文献   
85.
Two molecular forms of pyrophosphate-dependent phosphofructokinase (PPi-PFK; pyrophosphate:D-fructose-6-phosphate 1-phosphotransferase; EC 2.7.1.90) have been found whose activity depends upon association and dissociation characteristics regulated by fructose 2,6-bisphosphate (Fru-2,6-P2). PPi-PFK was purified 200-fold from cotyledons of germinating pea seeds and found to exist in two interconvertible molecular forms. The two forms of PPi-PFK have sedimentation coefficients of 6.3 and 12.7 S during ultracentrifugation in sucrose density gradients and also differ both in sensitivity to the activator Fru-2,6-P2 and in affinity for the substrate fructose 6-phosphate. The major component of enzyme activity is in the large form (12.7 S), but the small, less-active, form (6.3 S) predominates when the enzyme preparation is extracted and stored in buffer without Fru-2,6-P2 and glycerol. Urea (1 M) or pyrophosphate (20 mM) treatment results in at least a 50% loss of activity in the glycolytic direction, whereas these treatments had much less influence on the gluconeogenic direction activity. Concomitant with the loss of glycolytic activity the enzyme dissociates into the small form. Fru-2,6-P2 stabilizes the large form of the enzyme against the dissociating effects of pyrophosphate and prevents the inactivation in the glycolytic direction during either urea or pyrophosphate treatment. The small molecular form of the enzyme is converted into the large form in the presence of Fru-2,6-P2. We propose that glycolytic and gluconeogenic hexose metabolism in plants includes a regulatory mechanism induced by Fru-2,6-P2 that involves the interconversion of two molecular forms of PPi-PFK.  相似文献   
86.
Summary 2-deoxycoformycin (2-dCF; Pentostatin), a stoichiometric inhibitor of mammalian adenosine deaminase (ado deaminase), exhibits immunosuppressive and antilymphocytic activity in animal test systems. A clinical pharmacology/phase I study of 2-dCF administered as a single agent has been completed (18 patients). Dose levels ranged from 0.1 mg/kgx1 to 0.25 mg/kg/dayx5; ado deaminase and 2-dCF were measured spectrophotometrically. Plasma decay curves were bi-exponential ( and t1/2 values about 1 and 10 h respectively). Recovery of unchanged 2-dCF from urine (48 h) was 32%–48% of the administered drug. Major toxic manifestations were lymphocytopenia (all patients) and urate nephropathy (1 patient, with subsequent patients in the series receiving allopurinol, 300 mg/day). Three partial responses were seen in seven patients with acute lymphocytic leukaemia receiving 0.25 mg 2-dCF/kg/dayx5.  相似文献   
87.
In this prospective study, neonates with clinical congenital syphilis were investigated to determine if penicillin therapy caused a deterioration in liver function. The relationship between circulating immune complexes and liver involvement was monitored, and the efficacy of steroid therapy as an adjunct in the treatment of congenital syphilis was investigated. Thirty neonates with clinical congenital syphilis were randomly assigned into two groups: one group received penicillin therapy only, and the other group penicillin and prednisone as an adjunct. Twenty-one infants who did not have clinical or serological syphilis, born to seropositive mothers, served as a "control" group. Liver function tests, full blood counts, and immunological studies were performed at various intervals up to 3 months of age. Although the symptomatic groups differed significantly from the asymptomatic group in most of the parameters measured, there were no significant differences noted between the two symptomatic groups at any time point. No direct relationship between penicillin therapy and either deteriorating liver function or the presence of circulating immune complexes could be demonstrated. Also, prednisone therapy did not modify any of the parameters studied.  相似文献   
88.
Previous studies have demonstrated that is is the local immune response which is of importance for the anti-tumour activity of BCG therapy. We have investigated this by quantitative immunohistochemical analysis of serial bladder mucosal biopsies taken before, during and after an eight week course of intravesical Evans strain BCG therapy and three monthly thereafter in 16 patients (15 extensive CIS and one extensive G2pTa papillary tumour). This particular group of patients had a 67% complete response rate at six months post-treatment. The main findings on immunohistochemical analysis were the universal induction of MHC Class II antigens by urothelial cells which was statistically significant up to 6 months after completion of therapy, coupled with a T cell dominated cystitis. Increases in CD3+ T cell infiltration of the lamina propria and that of the CD4+ "Helper" subset which predominated were significant up to 3 months post-therapy and these cells showed evidence of increased immunological activation as shown by increased interleukin-2 receptor and MHC Class II antigen expression. There were also significant increases in CD68+ macrophage and the incidence of CD22+ B cell aggregates but CD57+ NK cells were sparse both before and after therapy. The degree of mononuclear cell infiltration for all markers examined (except CD57) was significantly greater in those biopsies in which the urothelial cells expressed MHC Class II antigens than in those that did not. Also the degree of T cell infiltration (CD3, CD4 and CD8) was significantly greater in the eight patients deemed to have had a complete response compared to those seven with a partial response or treatment failure. These results are discussed in terms of possible mechanisms of action for BCG therapy and in particular the role of enhanced antigen presentation by tumour cells.  相似文献   
89.
The operating microscope was originally introduced to provide better visualization and illumination for otologic surgery. The successful use of this instrument in the fenestration operation for otosclerosis rapidly led to its application to reconstructive procedures in chronic suppurative otitis media. Later, it became evident that the operating microscope also provided advantages in the treatment of inner ear disorders and in the removal of acoustic Schwannomas; a considerable reduction in morbidity and an improved prognosis have resulted from application of microsurgery to these conditions. In addition, new photographic and television equipment, used in combination with microsurgery, has greatly improved the standards of teaching and the recording of pathologic information.  相似文献   
90.
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