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BackgroundPatients with a preoperative varus deformity >8 degrees are at increased risk of aseptic loosening after total knee arthroplasty. This study analyzes the effect of a tibial stem on the rate of aseptic loosening in patients with a severe preoperative varus deformity.MethodsPatients with a preoperative varus deformity of >8 degrees and 2-year minimum follow-up with a stemmed tibial component (n = 67) were matched 1:2 to patients with a similar preoperative varus deformity with a standard tibial component (n = 134). Radiolucent lines were measured on the tibia at 6 weeks, 1 year, and 2 years postoperatively using the Knee Society Radiographic Evaluation System. Failure was defined as revision due to aseptic loosening of the tibial component. Outcomes were evaluated using Student’s t-tests and log-rank tests.ResultsPatients with tibial stems had greater preoperative deformity (12.9 vs 11.3 degrees, P = .004). There was no difference in postoperative alignment (1.7 vs 2.1 degrees varus, P = .25) or tibial component angle (1.8 vs 2.1 degrees varus, P = .33). Patients with stems were more likely to have more constraint (44.8% vs 1.5%, P < .001). Progression of radiolucent lines >2 mm was observed in 17.6% (23/134) vs 5.97% (4/67) of patients in the stem group (P = .03). Rates of aseptic loosening were lower in the stem group (0% vs 5.15%, P = .05).ConclusionDespite worse preoperative deformity and higher utilization of constraint, tibial stem use in patients with severe preoperative varus deformity resulted in lower rates of aseptic loosening. Prophylactic use of stems in these patients may help increase implant survival.  相似文献   
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Archives of Sexual Behavior - Sexual minority men (SMM) remain disproportionately burdened by sexually transmitted infections. Although gay community involvement has been theorized to be protective...  相似文献   
64.

At least 200 million girls and women across the world have experienced female genital cutting (FGC). International migration has grown substantially in recent decades, leading to a need for health care providers in regions of the world that do not practice FGC to become knowledgeable and skilled in their care of women who have undergone the procedure. There are four commonly recognized types of FGC (Types I, II, III, and IV). To adhere to recommendations advanced by the World Health Organization (WHO) and numerous professional organizations, providers should discuss and offer deinfibulation to female patients who have undergone infibulation (Type III FGC), particularly before intercourse and childbirth. Infibulation involves narrowing the vaginal orifice through cutting and appositioning the labia minora and/or labia majora, and creating a covering seal over the vagina with appositioned tissue. The WHO has published a handbook for health care providers that includes guidance in counseling patients about deinfibulation and performing the procedure. Providers may benefit from additional guidance in how to discuss FGC and deinfibulation in a manner that is sensitive to each patient’s culture, community, and values. Little research is available to describe decision-making about deinfibulation among women. This article introduces a theoretically informed conceptual model to guide future research and clinical conversations about FGC and deinfibulation with women who have undergone FGC, as well as their partners and families. This conceptual model, based on the Theory of Planned Behavior, may facilitate conversations that lead to shared decision-making between providers and patients.

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OBJECTIVE: This paper reviews the epidemiology, etiology, assessment, and management of bipolar disorder. Special attention is paid to factors that complicate treatment, including noncompliance, comorbid disorders, mixed mania, and rapid cycling. Advances in biopsychosocial treatments are briefly reviewed, including new health service models for providing care. METHODS: A MEDLINE search was done for the period from January 1988 through October 1997 using the key terms of bipolar disorder, diagnosis, and treatment. Papers selected for further review included those published in English in peer-reviewed journals. Preference was given to articles reporting randomized, controlled trials. RESULTS: Bipolar disorder is a major public health problem. The etiology of the disorder appears multifactorial. Diagnosis often occurs years after onset of the disorder. Comorbid conditions are common. Management includes a lifetime course of medication and attention to psychosocial issues for patients and their families. Standardized treatment guidelines for the management of acute mania have been developed. New potential treatments are being investigated. CONCLUSIONS: Assessment of bipolar disorder must include careful attention to comorbid disorders and predictors of compliance. Randomized trials are needed to further evaluate the efficacy of medication, psychosocial interventions, and other health service interventions, particularly as they relate to the management of acute bipolar depression, bipolar disorder co-occurring with other disorders, and maintenance prophylactic treatment.  相似文献   
67.
Periprosthetic fractures of the femur are a complex problem to treat. Careful planning is essential before embarking on such a technically demanding procedure. There are many factors to be considered, including the premorbid condition of the patient and previous experience and training of the surgeon. Important factors relating directly to the fracture include the site, stability of the implant, and the state of the surrounding bone stock.  相似文献   
68.
The treatment of dual diagnosis, co-occurring substance abuse and mental illness, calls for addressing two serious and often confounding problems. The authors introduce an expanded version of the transtheoretical model of change as formulated by J.O. Prochaska and C.C. DiClemente, and suggest that this new version offers a pragmatic approach to the conceptualization and treatment of dual diagnosis. The potential utility of the treatment model is presented through the authors' experiences in working with inner-city, chronic mentally ill individuals with substance abuse problems. Practical guidelines for dual diagnosis group therapy are discussed.Dr. Brady is an assistant research professor at the Boston University School of Medicine and the deputy superintendent for research and training at the Dr. Solomon Carter Fuller Mental Health Center. Drs. Hiam, Saemann, Humbert, Fleming and Brickhouse were senior members of the clinical/administrative staff at the Fuller MHC.  相似文献   
69.
The effects of cocaine on speech sound discriminations was examined to determine whether cocaine's previously demonstrated effect in reducing speech sound discriminability was dependent upon either the type of stimuli employed (simple tones versus complex speech) or the procedure (stimulus detection versus stimulus discrimination). Because of demonstrated similarities in the way that baboons and humans discriminate speech, and in the way the CNS is thought to encode and process speech sounds in these two species, baboons were trained to perform a choice procedure to identify the occurrence of different synthetic vowel sounds (/a/, /æ/, //, /U/, and /љ/). Animals held down a lever and released the lever only when one of four target vowels sounded, and not when a fifth, standard vowel sounded. Acute IM administration of cocaine (0.0032–1.0 mg/kg) produced dose-dependent decreases in vowel discriminability that were mostly due to elevations in false alarms (i.e., releases to the standard vowel) following cocaine. Cocaine also shortened reaction times to the stimuli in two of three baboons, but to a much lesser extent than observed previously. These results suggest that cocaine may interfere with the ability of the CNS to process the acoustic cues in speech sounds, and that the effects of cocaine on reaction times may depend upon the complexity of the reaction time procedure employed.  相似文献   
70.
Cocaine, diethylpropion, chlorphentermine, and fenfluramine were compared on a drug-maintained progressive-ratio procedure in baboons. Intravenous infusions of drug were contingent on completion of a fixed-ratio response requirement (fixed number of lever-press responses) with a 3-h time-out period following each infusion. Prior to testing each dose of drug, stable self-infusion performance was first established with 0.4 mg/kg cocaine when the fixed-ratio requirement was 160. Subsequently, a test dose of drug was substituted for the standard dose of cocaine. If the dose of drug maintained a criterion level of self-infusion performance (six or more infusions per day for 2 days), the ratio requirement was systematically increased every day until the breaking point at which the self-infusion performance fell below a criterion level (one or zero infusionsper day). Fenfluramine did not maintain criterion self-infusion performance at any dose tested (0.02–5.0 mg/kg). The dose ranges of the other drugs that maintained maximum breaking points were 1.0–5.6 mg/kg for chlorphentermine, 1.0–3.0 mg/kg for diethylpropion, and 0.1–0.4 mg/kg for cocaine. Within-animal comparison of the maximum breaking points indicated that cocaine maintained the highest breaking points, followed in order by diethylpropion, chlorphentermine, and fenfluramine. The rank ordering of these drugs with the breaking point measure corresponds well with both the results of other animal experiments on measurement of reinforcing efficacy of these drugs and with the clinical information about the human subjective effects and abuse of these drugs.  相似文献   
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