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41.
Objective: To examine the effectiveness of needle and syringe programmes (NSPs) in preventing HIV transmission among injecting drug users (IDUs).Methods: An ecological study design was used to determine change in HIV prevalence among injecting drug users between cities with and without NSPs. Several data sources, such as electronic journal databases, surveillance reports, websites, and index review of relevant journals, were used to identify studies of HIV seroprevalence among IDUs, and presence of NSPs. The rate of change in HIV prevalence was estimated by regression analysis.Results: There were 778 years of data from 99 cities globally included in the analysis. HIV prevalence decreased by 18.6% per annum in cities that introduce NSPs, and increased by 8.1% in cities that had never introduced NSPs (mean difference −24.7% [95% CI: −43.8, 0.5%], P=0.06). The mean difference was –33% when comparison was weighted to one over the variance of the regression estimator (29% decrease in cities with NSPs and 5% increase in cities without NSPs, P<0.001). When analysis was restricted to cities with first HIV seroprevalence less than 10%, the average annual change in seroprevalence was 18% lower in cities with NSPs (P=0.03).Conclusions: Despite the inherent limitations within an ecological study design, the study provides additional evidence that NSPs reduce transmission of HIV infection. The rapid spread of HIV among IDU populations and increasing rates of injecting in many countries calls for scaling up of NSPs as well as other harm reduction strategies.  相似文献   
42.
OBJECTIVE: The objective of this study was to determine if temporomandibular joint (TMJ) samples positive for Chlamydia trachomatis have a greater presence of tumor necrosis factor-alpha (TNFalpha) or interleukin-6 (IL-6) when compared with Chlamydia-negative samples. STUDY DESIGN: Posterior bilaminar tissue samples removed during TMJ surgery from 70 patients were evaluated. Cryosections were stained using monoclonal antibody that identifies C. trachomatis. The presence of IL-6 and TNFalpha were evaluated by immunostaining in 15 samples positive and in 25 samples negative for the presence of C. trachomatis. RESULTS: Of the 70 TMJ samples, 32 (46%) were positive for C. trachomatis. In 15 samples positive for C. trachomatis, 10 (67%) were positive for TNFalpha and 7 (47%) for IL-6. In 25 samples negative for C. trachomatis, only 4 (16%) were positive for TNFalpha and only 2 (8%) for IL-6. Differences in C. trachomatis-positive samples versus negative were significant for both TNFalpha (P < .002) and IL-6 (P < .008). CONCLUSION: The presence of C. trachomatis in the TMJ is associated with a significantly increased presence of TNFalpha and IL-6.  相似文献   
43.
Background contextLumbar zygapophyseal joint (Z-joint) synovial cysts can cause low back pain (LBP), spinal stenosis, and lower extremity radiculopathy. In the literature, there are several minimally invasive techniques described with mixed results. Typical recommended treatment is surgical resection of the cyst. Currently, there is little information available concerning the efficacy and outcome with treatment of Z-joint synovial cyst by percutaneous, fluoroscopic, contrast-enhanced distention, and rupture.PurposeTo evaluate the therapeutic value and safety of Z-joint cyst rupture in symptomatic patients.Study design/settingRetrospective cohort study in an academic outpatient physiatric spine practice.Patient sampleThirty-two patients with moderate-to-severe LBP and leg pain (18 women and 14 men with an age range of 46–86 y; mean age, 66 y) with an average preprocedure symptom duration of 5 months. The patient's clinical symptoms correlated with magnetic resonance imaging studies documenting the presence of a synovial cyst at the corresponding level and side of symptoms. Patients had at least 6 months follow-up (range, 6–24).Outcome measuresNumerical Pain Rating Scale, Roland-Morris Disability Questionnaire, North American Spine Society four-point patient satisfaction survey, recurrence of synovial cyst requiring repeat rupture, and need for surgical intervention.MethodsPatients with symptomatic lumbar Z-joint synovial cyst were identified and their charts were reviewed. Patients included in the study either had symptomatic lumbar LBP or LBP with associated lower extremity radiculopathy. All patients in the study had magnetic resonance imaging's documenting Z-joint synovial cyst that corresponded with the patients' clinical symptoms. All patients received fluoroscopically guided, contrast-enhanced, percutaneous facet cyst distention and rupture followed by an intra-articular facet joint injection of 1 cc kenalog and 1 cc of 1% lidocaine. Seventeen of the patients also received a transforaminal epidural steroid injection just before facet cyst rupture. Telephone follow-up was conducted on all patients.ResultsExcellent long-term (average follow-up 1 y; range, 6–24 mo) pain relief was achieved in 23 (72%) of 32 patients undergoing facet cyst rupture. Twelve patients (37.5%) had synovial cyst recurrence and 11 chose to undergo repeat rupture, which resulted in 5 patients (45%) obtaining complete relief of symptoms and 6 patients (55%) requiring surgical intervention for cyst removal. Fisher exact test demonstrated that all patients who did not have a cyst recurrence were a success and obtained complete relief of symptoms (p<.0002). Patients who underwent a repeat rupture had a 50% chance of a successful outcome. There was no statistical significance between a successful outcome and level of facet cyst rupture, the presence of spondylolisthesis, sex, age, or having a transforaminal epidural steroid injection at the time of the procedure. Wilcoxon signed-rank test demonstrated that the difference in Numerical Pain Rating Scale and Roland-Morris Disability Questionnaire scores before and after the procedure was statistically significant (p<.0001). No complications were reported.ConclusionsFluoroscopic percutaneous Z-joint cyst rupture appears to be a safe and effective minimally invasive treatment option. This procedure should be considered before surgical intervention.  相似文献   
44.
45.
Idiopathic retroperitoneal fibrosis. A retrospective analysis of 60 cases   总被引:5,自引:0,他引:5  
Sixty patients with idiopathic retroperitoneal fibrosis presenting between 1965 and 1984 are reviewed. Their mean age at presentation was 56 years and the male:female ratio was 3:1. The commonest presenting symptoms were flank and abdominal pain, weight loss, nausea and polyuria. Physical examination was usually normal, expect for the presence of hypertension. Anaemia and elevation of erythrocyte sedimentation rate were usually present. Proteinuria was found in less than a third of patients at presentation and significant bacteriuria was uncommon. The correct diagnosis was made or suspected in very few patients before referral. The cumulative actuarial survival rate was 86% at 1 year and 78% at 2 years. Seventeen patients died; they were significantly older and more uraemic at the time of referral than those who survived. A few patients did well with either corticosteroid therapy or ureterolysis alone. In the majority, both operation and steroid treatment were necessary. In bilateral obstruction with residual function in both kidneys, bilateral ureterolysis proved superior to unilateral operation (each followed by steroid therapy) in conserving renal function. Operation alone or steroid therapy alone should be considered in cases where steroids or surgery respectively present particular hazards. The less traumatic unilateral operation should be considered in poor risk patients and in those whose renal function is absent on one side. In many survivors, disease activity has persisted for many years. Life-long follow-up is recommended.  相似文献   
46.
Temporoparietal and posterior cingulate metabolism deficits characterize patients with Alzheimer's disease (AD). A H(2)(15)O resting PET scan covariance pattern, derived by using multivariate techniques, was previously shown to discriminate 17 mild AD patients from 16 healthy controls. This AD covariance pattern revealed hypoperfusion in bilateral inferior parietal lobule and cingulate; and left middle frontal, inferior frontal, precentral, and supramarginal gyri. The AD pattern also revealed hyperperfusion in bilateral insula, lingual gyri, and cuneus; left fusiform and superior occipital gyri; and right parahippocampal gyrus and pulvinar. In an independent sample of 23 outpatients with mild cognitive impairment (MCI) followed at 6-month intervals, the AD pattern score was evaluated as a predictor of cognitive decline. In this MCI sample, an H2(15)O resting PET scan was carried out at baseline. Mean duration of follow-up was 48.8 (SD 15.5) months, during which time six of 23 MCI patients converted to AD. In generalized estimating equations (GEE) analyses, controlling for age, sex, education, and baseline neuropsychological scores, increased AD pattern score was associated with greater decline in each neuropsychological test score over time (Mini Mental State Exam, Selective Reminding Test delayed recall, Animal Naming, WAIS-R digit symbol; Ps<0.01-0.001). In summary, a resting PET covariance pattern previously reported to discriminate AD patients from control subjects was applied prospectively to an independent sample of MCI patients and found to predict cognitive decline. Independent replication in larger samples is needed before clinical application can be considered.  相似文献   
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48.
Massive immune hemolysis due to passenger lymphocyte-derived anti-D has not been reported in renal transplantation. A 50-year-old (B-positive) male received a dual deceased-donor kidney transplant (B-negative) for diabetic renal failure. Two weeks post-transplant, the patient developed severe hemolytic anemia. The donor anti-D titer was 1:8. The recipient anti-D titer (zero pre-transplant) increased from 1:4 to 1:16 over 4 days. Rapid hemolysis caused severe anemia, minimum Hb = 4.2 g/dL, while selectively lysing the patient's autologous red cells during this time. The hemolytic anemia did not impair the allografts and subsided without monoclonal B-cell pharmacotherapy or apheresis. The anti-D titer decreased to barely detectable levels at four months and had cleared when checked 2 years post-transplant. Transfusion support subsided after two months. If complications of anemia can be avoided, the deleterious effects of hemolysis may be well tolerated by renal allografts using antigen negative transfusion alone.  相似文献   
49.
BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient.  相似文献   
50.
Laparoscopic prostatectomy has been accepted as an appropriate treatment for prostate cancer because of the shorter hospital stay and quicker recovery. We present a rare complication of groin hernia with incarceration and necrosis of small bowel following laparoscopic prostatectomy. Occult hernias and small fascia defects may not always be apparent pre-operatively, but extension of pneumoperitoneal insufflation to extraperitoneal compartments should alert the surgeon to the possible presence of such a defect.  相似文献   
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