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Of the various obsessive-compulsive phenomena it seems that compulsive checking may be particularly likely to repay an information-processing approach. There are indications that anxiety-targeted exposure methods are less appropriate to checking than cleaning. Also, repeated checking appears to result from an initial failure to process information adequately. Recent findings from experimental research on cognitive processes in obsessive-compulsive patients (e.g. difficulties in selective-set rather than filtering tasks, poor memory for actions, etc.) provide indications that compulsive checking may arise from a failure of information processing. Clinical observations indicate that the quality of information processing involved in checking deteriorates as checking is repeated, due partly to a deterioration of mood and partly to proactive interference. This suggests the use of cognitive strategies to maximize the effectiveness of the first check, so as to reduce the need for repetition.  相似文献   
23.
This study investigated the feasibility of using patient-controlled analgesia (PCA) effectively in a small 70 bed isolated rural hospital. The tirst 50 patients to use a Bard PCA 1, in the Port Lincoln Hospital, South Australia, were studied. The patients consumed morphine at a mean rate of 1.24 mg/h and used PCA for a mean of 48 h. Thirty-eight per cent of patients required treatment for nausea and other complications which is similar to the rate of those in other published series. Visual analogue pain scores showed excellent pain control, generally without evidence of oversedation; however, there was one episode of respiratory depression. Seventy-eight per cent of patients reported that their pain was relieved most or all of the time. The study demonstrated that a PCA service provided by nursing staff, the GP anaesthetist and rural surgeons is feasible in an isolated rural hospital.  相似文献   
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The validity of a hinged constant force probe (0.25 N) was compared with that of a similar but immobilised instrument, using the same interchangeable tip for both (0.64 mm diameter; 2 mm divisions). 60 sites were measured on teeth which were extracted subsequently, in patients with untreated periodontal disease, and the connective tissue attachment level was used as validity criterion. The clinical measurements of both probes correlated well with each other, but they differed significantly from the post-extraction connective tissue attachment level measurements, indicating a point 1.2 mm coronally to this, on average. A companion investigation of intra-operator probing depth reproducibility with the 2 probes, was undertaken in 14 patients, at 2 visits separated by 1 week in each case. All patients had untreated periodontal disease. A difference between probes was found at the first visit, but not at the second; the immobilised probe showed a difference between visits, reducing mean probing depth slightly at the second; when the immobilised probe was used first, there was a difference between probes. Further analysis of the results indicated that there was greatest agreement between probes when the constant force probe had been used before the immobilised probe at the second visit. The results suggested that these probes indicated a point above the connective tissue attachment level, related to pocket morphology, and that there was a moderate learning effect due to operator use of the constant force probe, which modified use of the immobilised probe.  相似文献   
26.
PURPOSE: To determine if there is an association between the timing of surgical intervention for congenital cataract within the first 12 weeks of life and the prevalence of postoperative complications. METHODS: We performed a retrospective review of records from 1990 to 2000 of infants who underwent surgery for congenital cataract within the first 12 weeks of life. Eighty eyes in 55 children were involved with a minimum follow up of 6 months. Bilateral cataracts were present in 25 and monocular cataracts in 30 infants. A limbal approach lensectomy-vitrectomy was performed in all infants. Children with aphakia were rehabilitated with contact lens or glasses. Operative and postoperative complications-including glaucoma, nystagmus, strabismus, retinal detachment, and posterior capsule opacification/secondary membranes-were recorded. Ocular and systemic associations were noted. Statistical analysis was carried out with classification and regression trees (CART). RESULTS: The mean age at the time of surgery was 31.5 +/- 23.3 days (median, 26.5; range, 2 to 84). Mean follow up from the time of surgery was 2.85 +/-1.9 years (median, 2; range, 0.5 to 8). Persistent fetal vasculature (persistent hyperplastic primary vitreous) was present in 14 eyes. One infant with bilateral persistent fetal vasculature had bilateral retinal dysplasia and was excluded from the analysis. Glaucoma developed in 12 infants (22%); nystagmus was present in 18 infants (33%); strabismus developed in 28 infants (52%); and secondary membranes developed in 7 eyes (13%). CART analysis suggests that glaucoma is more prevalent in infants when the surgery was performed between 13.5 and 43 days of life (CART = 0.370); nystagmus when surgery is performed between 48 and 84 days of life (CART = 0.500); strabismus when surgery is performed between 55.5 and 84 days of life (CART = 0.600); and secondary membranes when surgery is performed between 26.5 and 40 days of life (CART = 0.4). CONCLUSIONS: Our data suggest that the first 2 weeks of life comprise the most favorable time for decreasing postoperative complications resulting from surgical intervention for infants presenting with cataracts within the first 12 weeks of life.  相似文献   
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To investigate possible sex differences in central catecholaminergic systems, the concentrations of dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were measured by high-performance liquid chromatography with electrochemical detection in the hypothalamus-preoptic area (H-POA) and midbrain raphe (MR) region of male and female rats throughout postnatal development. Other than a small but significant sex difference in DA concentration in the MR at 36 h (higher in females), the results showed that there were no sex differences in the concentrations of DA or DOPAC at any age in either brain region. The developmental profiles of the concentrations of DA and DOPAC showed that DAergic systems in the H-POA are immature at birth, with concentrations increasing steadily until 80 days of age, but in the MR concentrations reach a maximum at 20 days of age; a situation which is perhaps a reflection of differing monoamine metabolism in the two areas.  相似文献   
29.
The authors describe spheric to ovoid chlamydoconidia and mucoraceous hyphae in tissues from four patients, two with cutaneous and two with pulmonary zygomycosis. The diagnosis in each case was confirmed by immunofluorescence staining and the presence of characteristic hyphae in tissue. It is important that these conidia be recognized, because they can easily be mistaken for other fungi, nematode ova, or other microorganisms in tissue sections, thereby resulting in the potential for misdiagnosis.  相似文献   
30.
In the previous article we have demonstrated, by quantifying terminal complement complexes in synovial fluid, that membrane attack complex activation occurs in the joint in rheumatoid arthritis. Here we describe evidence of synoviocyte resistance to complement attack in vivo and in vitro. Gel filtration of terminal complement complex positive synovial fluid on Sepharose 2B revealed two forms of terminal complement complex: one form, eluting coincident with the column void, did not react with antibody to the fluid-phase inhibitor of complement membrane attack, the S-protein, suggesting that it was composed of membrane attack complexes, the other form, eluting in the included volume, did react with the anti-S-protein antibody, suggesting that it was composed of functionally inactive SC5b-9 complexes. The high molecular weight membrane attack complex peak was demonstrated by electron microscopy to be composed of membrane vesicles bearing many lesions having the typical appearance of complement membrane attack complexes. No discernible structures were present in the lower molecular weight peak. The effects of non-lethal complement membrane attack on human synoviocytes in culture were also investigated. Synoviocytes were relatively resistant to killing by autologous complement, end-point lysis of optimally antibody-sensitized cells never exceeding 60% even at a serum dilution of 1:2. At serum dilutions of 1:20 or less, no significant cell killing occurred despite a high degree of membrane attack pathway activation, suggesting the existence of resistance and recovery mechanisms. Non-lethal complement membrane attack stimulated the release of toxic reactive oxygen metabolites from synoviocytes. These, and other reactive species released during non-lethal complement attack in vivo, may play a significant role in the pathogenesis of rheumatoid arthritis.  相似文献   
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