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31.
Smith  TP; Cragg  AH; Berbaum  KS 《Radiology》1989,170(3):941
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32.
Background  Alopecia areata is a complex genetic disease with still many unknown aspects, and many studies have been tried to find some clues about it.
Objective  We aimed to investigate the demographic and clinical characteristics of alopecia areata in Turkish patients.
Methods  Demographic data, localization, attack number in addition to some parameters such as disease duration, severity, age of onset, family history and ophiasis pattern were evaluated in 539 alopecia areata patients.
Results  The male to female ratio was 1.6 : 1. Occipital and beard-moustache areas were mostly affected. Positive family history was noticed in 24.1% of the patients. The age of onset was earlier in women than in men ( P =  0.04). Severe forms showed more persistent (≥ 1 year) disease duration ( P =  0.00). Ophiasis was more common in severe, long duration (≥ 1 year) and early onset (≤ 18 years) disease ( P =  0.00 for all parameters). Childhood alopecia areata (≤ 18 years) was also associated with long duration of the disease ( P =  0.016) and positive family history ( P =  0.008) when compared with adult onset (> 18 years) alopecia areata.  相似文献   
33.
Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study.  相似文献   
34.
The radiographic findings in five pediatric patients in whom unregulated B-cell lymphoproliferative disorders developed following bone marrow transplantation are described. Four patients received T-cell-depleted bone marrow from mismatched donors and one received nondepleted marrow from a matched sibling donor. These disorders are similar to B-cell lymphoproliferative disorders that have been described in other immunosuppressed hosts. They are associated with Epstein-Barr virus and range from polyclonal proliferation without cytogenetic abnormalities to monoclonal lymphoma with clonal cytogenetic changes. Unlike other postallograft lymphoproliferative processes, B-cell lymphoproliferative disorders in these patients have not responded to antiviral therapy, immunologic therapy, or chemotherapy. The radiographic patterns of disease include diffuse or focal hepatic involvement; gallbladder wall thickening; and pulmonary, soft-tissue, and basal-ganglion masses. These radiologic findings are not specific and evaluation of tissue histology is required for diagnosis.  相似文献   
35.
36.

Background  

DNA fingerprinting of Mycobacterium tuberculosis isolates offers better opportunities to study links between tuberculosis (TB) cases and can highlight relevant issues in urban TB control in low-endemic countries.  相似文献   
37.
38.

Background

Neoadjuvant chemotherapy (NAC) has been shown to improve survival in patients with urothelial carcinoma (UC). However, there are a subset of patients who do not respond or progress despite systemic treatment.

Methods

Data from the National Cancer Database on patients who underwent a radical cystectomy (RC) with or without NAC from 2006 to 2013 were abstracted. Covariates were balanced using inverse probability weighting methods. The primary outcome of overall survival in patients with residual disease by stage was evaluated using 90-day conditional landmark analysis and Cox proportional hazards modeling. Secondary outcome of predictors of residual disease was evaluated using multivariable logistic regression analysis.

Results

A total of 20,128 patients met our inclusion criteria; 16,058 patients underwent RC only (80%) and 4070 underwent RC with NAC (20%). Patients who received NAC were younger and healthier, treated at an academic center, and presented with higher stage. NAC was associated with improved overall survival amongst patients with cT3-4aN0 (HR 0.84 95% CI 0.73–0.97; p?=?0.02) and cN+ (HR 0.70, 95% CI 0.58–0.86; p?=?0.001). Predictors of no residual disease were NAC (OR 0.17, 95% CI 0.14–0.21; p?<?0.001) and treatment at an academic facility (OR 0.47, 95% CI 0.37–0.60; p?<?0.001). Patients with cT3-4a or cN+ had increased odds of having residual UC (OR 2.01, 95% CI 1.53–2.64; p?<?0.001, and OR 2.14, 95% CI 1.43–3.21; p?<?0.001, respectively) compared with cT2.

Conclusion

In patients with residual UC, NAC is associated with a significant survival benefit in higher stage disease only. Furthermore, those treated with NAC or at an academic center were less likely to have residual disease. Given the toxicity of NAC, more prudent patient selection for NAC is warranted and requires further study.
  相似文献   
39.
To determine the factors that influenced doctors' prioritization and decisions on safe waiting time for coronary artery bypass surgery, 50 'paper patients', based on a random sample of cases who actually had surgery, were assessed by 33 clinicians. We used linear regression models to reflect the impact of clinical and non-clinical 'cues' on safe waiting time and priority decisions. The benefits of surgery tended to be over-estimated. For example, the average perceived gain in life expectancy for patients with left main-stem disease was 6.74 years. However, models incorporating only the perceptions of benefit as independent variables (i.e. the anticipated symptom reduction, MI risk reduction and life expectancy extension), had only modest explanatory power (mean R2 was 0.55 for safe waiting time, and 0.56 for priority decisions). Models which incorporated perceptions of benefit and the cases' clinical and non-clinical characteristics had generally much higher explanatory power (mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables had much less impact on the doctors' judgements than the major clinical cues of angina severity and left main-stem stenosis. Demographic and lifestyle cues had different impacts on safe waiting time and priority for about 25% of doctors.   相似文献   
40.
Although fractures of the clavicle are common, complications are rare. A 41 year old painter developed two uncommon complications of clavicular fracture, mechanical intermittent subclavian artery occlusion and subclavian vein thrombosis. Both conditions were clearly identified on the clinical symptoms and signs and confirmed with dynamic angiography and computerised tomography. Operative intervention led to complete resolution of symptoms.  相似文献   
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