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51.
To determine whether the Osgood-Schlatter lesion (OS) is produced by avulsion fracture or injury to the patellar tendon, all images obtained in 28 cases of OS in 20 patients (16 scintigrams, 34 computed tomographic [CT] scans, and 27 magnetic resonance [MR] images) were retrospectively analyzed. In 21 cases, imaging was performed before and after treatment; in 20 cases, relief from pain was complete at the time of repeat examination. In all patients (100%), abnormal size of the tendon, decreased attenuation, and increase in signal intensity were compatible with the CT and MR imaging appearance of tendinitis. Distended deep infrapatellar bursa was a frequent finding, particularly on MR studies. These abnormalities had partially disappeared at follow-up examination. An ossicle was seen in only nine of 28 cases (32%); in three of seven cases with follow-up, the ossicle remained nonunited to the tibial tuberosity on follow-up studies despite relief from symptoms. This implies that healing of fracture is not essential for relief from symptoms. These results strengthen the argument that in most cases of OS, insult to the tendon and associated soft tissues, rather than avulsion fracture, causes OS.  相似文献   
52.
Abstract Factors influencing the remarkable growth of home health care include increased elderly population, decreased average length of hospital stay, and technological advancements that reduce the need for hospitalization. Societal changes have prompted increasing concern about personal risk to home care providers. The purpose of this pilot study was to: 1) ascertain factors related to perception of risk by home health care administrators and staff and to identify strategies used by home health care administrators to reduce risk to staff; and 2) determine whether quality of care is affected when home-visit situations present risk. A convenience sample of 36 home health care administrators and 62 staff was surveyed about risks and measures provided by the home health care agency to minimize risk. Factors associated with risk are geographic location, high incidence of crime, inappropriate patient or caregiver behavior, infectious diseases, and evening assignments. Strategies used to minimize risk include safety programs, preplanning of visits, personal protective equipment, escorts, and buddy systems. Perceived ability to refuse high-risk assignments, however, is questionable, as 66% of the staff stated that they leave a situation "as soon as possible." These findings will be used to strengthen inservice programs and to provide a basis for future studies.  相似文献   
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54.
Both HIV infection and methamphetamine dependence can be associated with brain dysfunction. Little is known, however, about the cognitive effects of concurrent HIV infection and methamphetamine dependence. The present study included 200 participants in 4 groups: HIV infected/methamphetamine dependent (HIV+/METH+), HIV negative/methamphetamine dependent (HIV-/METH+), HIV infected/methamphetamine nondependent (HIV+/METH-), and HIV negative/methamphetamine nondependent (HIV-/METH-). Study groups were comparable for age, education, and ethnicity, although the HIV-/METH- group had significantly more females. A comprehensive, demographically corrected neuropsychological battery was administered yielding a global performance score and scores for seven neurobehavioral domains. Rates of neuropsychological impairment were determined by cutoff scores derived from performances of a separate control group and validated with larger samples of HIV+ and HIV- participants from an independent cohort. Rates of global neuropsychological impairment were higher in the HIV+/METH+ (58%), HIV-/METH+ (40%) and HIV+/METH- (38%) groups compared to the HIV-/METH- (18%) group. Nonparametric analyses revealed a significant monotonic trend for global cognitive status across groups, with least impairment in the control group and highest prevalence of impairment in the group with concurrent HIV infection and methamphetamine dependence. The results indicate that HIV infection and methamphetamine dependence are each associated with neuropsychological deficits, and suggest that these factors in combination are associated with additive deleterious cognitive effects. This additivity may reflect common pathways to neural injury involving both cytotoxic and apoptotic mechanisms.  相似文献   
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56.
Context.— The use of serologic testing to diagnose Lyme disease (LD) is a source of controversy. Expert recommendations also discourage the routine use of antibiotic therapy for prophylaxis of LD following tick bites, but the extent to which physicians in endemic areas have adopted these recommendations is not known. Objective.— To assess the pattern of use of serologic testing and antibiotic therapy for tick bites and LD and associated charges for management in an endemic area. Design.— Active surveillance of patient-physician encounters for tick bites and LD. Setting.— Primary care practices on the Eastern Shore of Maryland. Patients.— Consecutive sample of 232 patients with tick bites, LD (defined by physician diagnosis in medical record), and suspected LD (physician notation of possible, but not definite LD) seen in 1995. Main Outcome Measures.— Serologic testing for LD, test results, antibiotic therapy, and direct costs of management. Results.— Surveillance identified 142 patients (61.2%) with diagnoses of tick bites, 40 patients (17.2%) with LD, and 50 patients (21.6%) with suspected LD. Of the 142 patients seen for tick bites, 95 (67%) underwent serologic testing for LD. Of these, 93 patients had initial negative or equivocal results; 24 (26%) of the 93 had convalescent testing, with 1 seroconversion. Seventy-eight patients (55%) with a diagnosis of tick bite received antibiotic therapy. No patients with tick bite developed clinical LD. Serologic testing for LD was performed for 36 patients (90%) with a diagnosis of LD and 46 patients (92%) with suspected LD. In most cases, antibiotics were prescribed before serologic test results became available. Convalescent testing was not performed for 37 (86%) of the 43 patients with suspected LD who had initial negative or equivocal results. Of these 37 patients, 25 (68%) did not receive antibiotic therapy. Direct charges for treatment of these 232 patients totaled $47595, one third of which was attributable to serologic testing. A total of 32% of direct charges were for patients with tick bites, 48% were for patients with LD, and 20% were for patients with suspected LD. Conclusions.— In this setting, most patients consulting physicians for tick bites received prophylactic antibiotic therapy of unproven efficacy and underwent unnecessary, costly serologic testing. Despite almost universal use in this study, serologic testing for LD did not appear to influence treatment of patients diagnosed as having LD.   相似文献   
57.
The role of the ethanol training dose on the ability of the selective 5-HT1 agonist TFMPP (m-trifluoromethylphenylpiperazine) to produce ethanol-like discriminative stimulus effects was evaluated in three groups of rats trained to discriminate 1.0 g/kg (n=5), 1.5 g/kg (n=6) or 2.0 g/kg (n=7) ethanol (IG) from water using a two-lever procedure with food reinforcement available under a fixed ratio 20 (FR 20) schedule. Ethanol generalization gradients were comparable in the three groups, indicating few potency differences in the ethanol stimulus across training dose. However, the ability of TFMPP (0.1–1.7 mg/kg; IP) to substitute for ethanol was dependent on the training dose. TFMPP resulted in partial substitution in the 1.0 g/kg group, complete substitution for 1.5 g/kg group and no substitution in the 2.0 g/kg ethanol training group. The results indicate a serotonergic component to the discriminative stimulus effects of an intermediate dose of ethanol that is not prominent as the dose of ethanol is raised. These data add further support for the hypothesis that ethanol produces a mixed discriminative cue, the components of which are not uniformly amplified when the dose of ethanol is increased.  相似文献   
58.
The "Learn Not to Burn" prevention program is a burn prevention curriculum sponsored by the North Carolina Jaycee Burn Center, the State Department of Public Instruction, and the North Carolina Department of Insurance Fire and Rescue Division. The goal of the program is to reduce burn-related deaths and injuries in North Carolina through burn prevention education by making the "Learn Not to Burn" curriculum available to primary school children across the state at no cost to the schools. The curriculum instrument is a reusable notebook that provides a means for teachers to integrate burn prevention into regular class subject areas. At the time of initiation of this study approximately 70% of the school systems in North Carolina had been provided with the "Learn Not to Burn" curriculum.  相似文献   
59.
We evaluated the relationship between life events, social support, coping, and depression in 27 male inpatients meeting the requirements for Research Diagnostic Criteria major depressive disorder and in 35 age- and sex-matched nonpatients. Overall, the hospitalized depressed patients reported significantly more events and difficulties than did the controls, but this difference in statistical significance disappeared after excluding from analysis "non-independent" happenings which could have been brought on by depression. More hospitalized depressed patients (23 of 27, or 85%) than controls (8 of 35, or 22.9%) experienced markedly threatening events and difficulties ("marked adversities") in the 6 months before their interview. The depressed group also reported having significantly fewer social supports, being less satisfied with the emotional component of this support, and using more emotion-focused coping than the controls. A discriminant analysis predicted depressive status from a combination of marked adversities, reduced number of social supports, and greater use of emotion-focused coping. The results indicate that the relationship of life events to depression is complex. The excess number of events might be partly a product of dysfunctional behavior that "produces" depression-related events which might, in turn, exacerbate depression; simultaneously, patients are more likely to experience highly adverse events which might precipitate the depression in the first place. Reduced social supports and the use of emotion-focused coping appear to also be associated with hospitalization for major depression.  相似文献   
60.
Pancreatic pseudotumor in pancreas divisum: CT characteristics   总被引:1,自引:0,他引:1  
We report a case in which a focally spared area of pancreatic tissue in a gland otherwise replaced by fat created a "pseudomass" mimicking neoplasm on sonography and CT. The "pseudomass" appearance was related to the anomalous ductal anatomy in pancreas divisum. The spared area of pancreas creating a "pseudomass" was drained by the dorsal duct and the remainder of the pancreas that had undergone relative fatty replacement was drained by the ventral duct.  相似文献   
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