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41.
Bile duct obstruction: radiologic evaluation of level, cause, and tumor resectability 总被引:6,自引:0,他引:6
Gibson RN; Yeung E; Thompson JN; Carr DH; Hemingway AP; Bradpiece HA; Benjamin IS; Blumgart LH; Allison DJ 《Radiology》1986,160(1):43-47
In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction. 相似文献
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Gazitt Y; Reading CC; Hoffman R; Wickrema A; Vesole DH; Jagannath S; Condino J; Lee B; Barlogie B; Tricot G 《Blood》1995,86(1):381-389
High-dose therapy with autologous marrow or peripheral blood stem cell (PBSC) rescue has been extensively applied in the treatment of multiple myeloma (MM) patients during the past 10 years resulting in improved event-free and overall survival when compared with standard chemotherapy. However, relapses are common and cure is unlikely in the majority of patients. Because both bone marrow and PBSCs are contaminated with myeloma cells it is conceivable that relapse after autotransplantation originates at least in part from autografted tumor cells. In this study, mobilized PBSCs were examined for the presence of myeloma cells based on immunophenotyping and sensitive polymerase chain reaction (PCR)-based techniques. In addition, CD34+ Lin- Thy+ stem cells were purified from mobilized PBSC harvests of 10 MM patients by sequentially using counterflow elutriation centrifugation, treatment with phenylalanine methylester, and flow sorting, using 5-parameter gating (propidium iodide, forward scatter, side scatter, CD34+ v Lin- and CD34+ v Thy+). Virtually all mobilized unsorted PBSC preparations contained myeloma cells in sufficient quantities (range, < 0.01 to > 10%) potentially causing a disease relapse. Stem cell purification led to an overall enrichment by about 50-fold in all 10 patients; approximately 90% of the final cell population expressed CD34+ Lin- Thy+ with no evidence of myeloma cell contamination based on flow cytometric analysis of CD38bright cells (< 0.1%). Quantitative PCR amplification of patient-specific complementarity determining region III (CDRIII) DNA sequences showed depletion of clonal B cells by 2.7 to 7.3 logs, with the highest log reduction noted in the samples initially containing the most tumor cells. Our results show that purification of CD34+ Lin- Thy+ cells depletes myeloma cells to undetectable levels from up to 10% present in unsorted PBSCs, thus offering a tool to investigate whether MM relapse after autotransplantation can be reduced markedly. 相似文献
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Malacco E Mancia G Rappelli A Menotti A Zuccaro MS Coppini A;Shell Investigators 《Blood pressure》2003,12(3):160-167
OBJECTIVE: Our aim was to compare the effect of lacidipine and chlorthalidone on cardiovascular outcome as a primary parameter and blood pressure as a secondary in elderly patients with isolated systolic hypertension in a prospective study with an open design. METHODS: 1882 males and females outpatients > or = 60 years were randomly assigned to the administration of chlorthalidone 12.5 mg o.d. or lacidipine 4 mg o.d. Patients were recruited if sitting systolic blood pressure was > or = 160 mmHg with a diastolic blood pressure equal or lower than 95 mmHg. Primary endpoint was a composite of cardiovascular and cerebrovascular events. RESULTS: At randomization mean systolic blood pressure was 178.1 mmHg in the lacidipine and 178.2 mmHg in the chlorthalidone group, the corresponding mean diastolic values being 86.9 and 86.8 mmHg. In both lacidipine and chlorthalidone groups treatment caused a significant (p < 0.001) and marked systolic blood pressure reduction which was maintained throughout the treatment period with a significant (p < 0.001) and steady although less marked reduction in diastolic blood pressure as well. At the end of treatment period (median 32 months), the reduction was 36.8/8.1 mmHg (systolic/diastolic) in the chlorthalidone and 38.4/7.9 mmHg in the lacidipine group, the final on treatment blood pressures being 142.0/79.2 and 143.2/79.5 mmHg, respectively. Treatments were similarly effective in males and females and in age groups between 60 and 69 years (n = 763), 70 and 79 years (n = 744) and > or = 80 years (n = 375). Similar reductions were obtained in a subgroup of patients (n = 209) followed in double-blind fashion for 1 year. The overall incidence of the primary endpoints was 9.3% with no significant between-group difference. Total mortality was also similar between groups. CONCLUSIONS: In elderly patients with isolated systolic hypertension, administration of lacidipine or chlorthalidone markedly reduced systolic blood pressure with no difference in the incidence of cardiovascular events and total mortality. 相似文献
46.
Femke?DH?Koedijk Birgit?HB?van BenthemEmail author Eliane?MDC?Vrolings Wim?Zuilhof Marianne?AB?van der Sande 《Emerging themes in epidemiology》2014,11(1):12
Background
Men having sex with men (MSM) remain the largest high-risk group involved in on-going transmission of sexually transmitted infections (STI), including HIV, in the Netherlands. As risk behaviour may change with age, it is important to explore potential heterogeneity in risks by age. To improve our understanding of this epidemic, we analysed the prevalence of and risk factors for selected STI in MSM attending STI clinics in the Netherlands by age group.Methods
Analysis of data from the national STI surveillance system for the period 2006–2012. Selected STI were chlamydia, gonorrhoea, infectious syphilis and/or a new HIV infection. Logistic regression was used to identify factors associated with these selected STI and with overall STI positivity. Analyses were done separately for MSM aged younger than 25 years and MSM aged 25 years and older.Results
In young MSM a significant increase in positivity rate was seen over time (p?<?0.01), mainly driven by increasing gonorrhoea diagnoses, while in MSM aged 25 and older a significant decrease was observed (p?<?0.01). In multivariate analyses for young MSM, those who were involved in commercial sex were at higher risk (OR: 1.5, 95% CI: 1.2-1.9). For MSM aged 25 years and older this was not the case. Having a previous negative HIV test was protective among older MSM compared to those not tested for HIV before (OR: 0.8, 95% CI: 0.8-0.8), but not among younger MSM.Conclusions
MSM visiting STI clinics remain a high-risk group for STI infections and transmission, but are not a homogenous group. While in MSM aged older than 25 years, STI positivity rate is decreasing, positivity rate in young MSM increased over time. Therefore specific attention needs to be paid towards targeted counselling and reaching particular MSM sub-groups, taken into account different behavioural profiles.47.
48.
Objective We hypothesized that the drinking behavior of adolescents in China is influenced by expectancies and self‐efficacy and that adolescents' cultural orientation towards western versus traditional Chinese values influences expectancies, self‐efficacy and drinking behavior, with western values leading to more dysfunctional patterns of beliefs and drinking, and that these beliefs are influenced by students' gender and school environment. Methods A total of 1020 high school students from Beijing completed the Chinese Adolescent Alcohol Expectancy, the Chinese Cultural Orientation and the Chinese Self‐regulation Self‐efficacy questionnaires. Results Results generally confirmed our hypotheses. Higher negative expectancies and higher self‐efficacy reduced the likelihood of drinking significantly. Higher positive expectancies increased the likelihood of regular drinking but not occasional drinking. Having western cultural orientation increased the likelihood of drinking. Higher levels of western cultural orientation also increased positive expectancies, lowered negative expectancies and lowered self‐efficacy. Having more western (less traditional) views towards traditional Chinese values decreased positive and negative expectancies. Gender influenced beliefs, with males having higher positive and lower negative expectancies, lower self‐efficacy and more traditional cultural orientation. Students in key and general schools had less traditional cultural orientation and key school students had higher self‐efficacy. Conclusions Results indicate that cultural orientation influences adolescent drinking and this influence is mediated partially through cultural orientation influences on adolescent drinking expectancies and self‐efficacy. Having more western and less traditional Chinese cultural orientation leads to more drinking, lower self‐efficacy for regulating drinking and more risk‐promoting alcohol expectancies. 相似文献
49.
Acute bronchial obstruction by mucous plugs may be manifested clinically by dyspnea, hypoxemia, and respiratory alkalosis mimicking pulmonary thromboembolism. In eight cases with complete interruption of ventilation to an entire lung, chest radiography failed to reveal the extent of the obstruction. Perfusion was substantially less affected than ventilation. Routine ventilation-perfusion scintigraphy with technetium-99m DTPA aerosol aids in the diagnosis of acute major bronchial obstruction in patients with suspected pulmonary thromboembolism. 相似文献
50.
A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree. 相似文献