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目的:探讨感染性心内膜炎(IE)的病因,致病微生物的变迁及抗生素的选择。方法:对1995年5月~2003年8月间住院的30例IE患者的临床资料进行回顾性分析。结果:风湿性心脏瓣膜病为其主要的基础心脏病变。链球菌在致病微生物中依然居首位,但凝固酶阴性葡萄球菌(CNS)等其它菌种逐渐增多,且对青霉素耐药发生率高,为临床诊治造成困难。结论:对于IE患者应尽可能早期明确诊断,早期选用有效的抗生素。CNS在IE的致病微生物中的地位有待进一步提高。  相似文献   
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Objective To investigate the clinical and pathological characteristics of pauci-immune crescent glomerulo~nephritis (PICGN) in Chinese patients. Methods During 13 years (1985-1998), 6400 patients underwent non-transplanting renal biopsy. Twenty-four patients were diagnosed as PICGN. All clinical and laboratory data of these patients were collected from the patients’ records and used for detailed analysis. The diagnosis is based on clinico-pathologic findings. Results Of the 24 patients, 16 were females and 8 were males, with median age of 33 years (ranged 10-76 years). Microscopic polyarteritis (MPA) (33.3%) and systemic vasculitis (8.3%) were the secondary diseases. The incidence of PICGN was 0.38% in renal biopsies and 22.9% in crescentic glomerulonephritis. Clinically, most patients (75.0%) showed rapidly progressive nephritis with enlarged kidneys. At onset, gross hematuria was noted in 58.3% of patients, hypertension in 45.8%, nephrotic syndrome in 41.7%, and oliguria in 25.0%. However, systemic symptoms were rare except for anemia. Pathologically, necrosis of glomerular capillaries (62.5%), infiltration of monocytes and neutrophil cells in glomeruli (66.7%), and vasculitis in the interstitium (53.3%) were observed. In addition, glomerulosclerosis was noted in 45.8%, severe tubular atrophy in 83.3% and interstitial fibrosis in 75.0%. Anti-neutrophil cytoplasmic antibodies (ANCAs) were positive in 52.2%. All patients except two received intensively immunosuppressive therapy. Sixteen patients were available for long-term follow up (median 29.8 months, range 8-92 months). Twelve of them had life-sustaining renal function, four had normal serum creatinine (<124?μmol/L) and only 4 patients were dialysis-dependent. Conclusion PICGN is not rare in China. Early diagnosis and administration of immunosuppressive therapy, particularly in patients with rapidly progressive glomerulonephritis (RPGN), are important for good prognosis.  相似文献   
24.
大花紫玉盘中新多氧取代环己烯类的结构鉴定   总被引:3,自引:0,他引:3  
从番荔枝科紫玉盘属植物大花紫玉盘( Uvaria grandiflora Roxb.)根茎中分得4种新的多氧取代环己烯及已知化合物zeylenol,应用波谱分析、X-射线衍射、园二色谱和 Mosher 酯制备等手段确定了全部新化合物的结构及其绝对构型,分别命名为大花紫玉盘醇A(1),B(2),E(3)和F(4)。  相似文献   
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The aim of the study was to compare the safety and effectiveness of as-needed formoterol with salbutamol in a large international real-life asthma study. Children and adults (n=18,124) were randomised to 6 months as-needed treatment with open-label formoterol 4.5 microg Turbuhaler or salbutamol 200 microg pressurised metered dose inhaler or equivalent. Primary safety variables were asthma-related and nonasthma-related serious adverse events (SAE)s and adverse events (AE)s resulting in discontinuation (DAE)s. The primary efficacy variable was time to first asthma exacerbation. The incidences of AEs, SAEs and DAEs arising from SAEs were not significantly different between treatments. DAEs for nonserious AEs were higher with formoterol. Asthma-related AEs decreased with formoterol (1,098 (12.3%) versus 1,206 (13.5%)), asthma-related SAEs were similar (108 (1.2%) versus 121 (1.4%)) but more asthma-related DAEs occurred in the formoterol group (89 (1.0%) versus 48 (0.5%)). Time to first exacerbation was prolonged (hazard ratio 0.86) and less as-needed and maintenance medication was used with formoterol. Reductions of exacerbations with as-needed formoterol versus salbutamol increased with increasing age and asthma medication level. This real-life study demonstrates that formoterol as-needed has a similar safety profile to salbutamol, and its use as a reliever therapy is associated with fewer asthma symptoms and exacerbations.  相似文献   
27.
Subjects with serological markers for a past HBV infection may still have HBV DNA in their serum, but the levels of viraemia in such cases are not known. In the present study, of 63 consecutive HBsAg-negative, anti-HBc-positive serum samples with or without anti-HBs, 20 were HBV DNA-positive as analysed by a highly sensitive quantitative PCR, the Cobas Amplicor HBV Monitor test. However, all of these 20 samples had viraemia levels below 1000 copies/ml, compared with median viraemia levels of 10(8.6) and 10(4.3) copies/ml, respectively, in 98 HBeAg-positive and 124 HBeAg-negative HBsAg carriers. There was no difference in viraemia between subjects with anti-HBc alone compared with both anti-HBs and anti-HBc, nor between those with or without hepatitis C virus antibodies. The findings indicate that HBsAg-negative subjects may retain a low infectivity. Their risk for progressive liver damage is probably low, but this deserves further study.  相似文献   
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Objective:Chemoradiation (CRT) may induce a change in systemic inflammatory state which could affect clinical outcomes in oesophageal cancer. We aimed to evaluate the changes and prognostic significance of systemic inflammatory markers following definitive CRT in oesophageal squamous cell carcinoma.Methods:A total of 53 patients treated with concurrent CRT were included in this retrospective analysis. We compared neutrophils, lymphocytes, platelets, neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) before and after CRT using Wilcoxon signed-rank test. Overall survival (OS) and progression-free survival (PFS) were calculated. Univariable and multivariable survival analysis were performed using Cox regression analysis. Clinical univariable survival prognostic factors with p < 0.1 were included in a multivariable cox regression analysis for backward stepwise model selection.Results:Both NLR (median ∆+2.8 [IQR −0.11, 8.62], p < 001) and PLR (median ∆+227 [81.3–523.5], p < 0.001) increased significantly after CRT. Higher levels of pre-CRT, post-CRT and change (∆) in NLR and PLR were associated with inferior OS and PFS. Post-CRT NLR (HR 1.04, 95% CI 1.02–1.07, p < 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.005), cT-stage (HR 3.83, 95% CI 1.39–10.60, p = 0.01) and RT dose (HR 0.41, 95% CI 0.21–0.81, p = 0.01) were independent prognostic factors for OS in multivariable analysis. Change in NLR (HR 1.04, 95% CI 1.01–1.06, p = 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.002), cT-stage (HR 3.98, 95% CI 1.55–10.25, p = 0.004) and RT dose (HR 0.41, 95% CI 0.21–0.80, p = 0.009) were independent prognostic factors for PFS.Conclusion:Both NLR and PLR increased following definitive CRT. Post-CRT NLR and ∆NLR were associated with adverse survival in oesophageal SCC.Advances in knowledge:We showed that CRT increased PLR and NLR, possibly reflecting a systemic inflammatory state which were associated with poor clinical outcomes in oesophageal SCC.  相似文献   
30.

Objective:

To estimate effective dose of cone beam CT (CBCT) of the facial skeleton with focus on measurement methods and scanning protocols.

Methods:

A systematic review, which adhered to the preferred reporting items for systematic reviews (PRISMA) Statement, of the literature up to April 2014 was conducted. Data sources included MEDLINE®, The Cochrane Library and Web of Science. A model was developed to underpin data extraction from 38 included studies.

Results:

Technical specifications of the CBCT units were insufficiently described. Heterogeneity in measurement methods and scanning protocols between studies made comparisons of effective doses of different CBCT units and scanning protocols difficult. Few studies related doses to image quality. Reported effective dose varied across studies, ranging between 9.7 and 197.0 μSv for field of views (FOVs) with height ≤5 cm, between 3.9 and 674.0 μSv for FOVs of heights 5.1–10.0 cm and between 8.8 and 1073.0 μSv for FOVs >10 cm. There was an inconsistency regarding reported effective dose of studies of the same CBCT unit with the same FOV dimensions.

Conclusion:

The review reveals a need for studies on radiation dosages related to image quality. Reporting quality of future studies has to be improved to facilitate comparison of effective doses obtained from examinations with different CBCT units and scanning protocols. A model with minimum data set on important parameters based on this observation is proposed.

Advances in knowledge:

Data important when estimating effective dose were insufficiently reported in most studies. A model with minimum data based on this observation is proposed. Few studies related effective dose to image quality.Since introduction in the late 1990s, cone beam CT (CBCT) has become a common modality to image the facial skeleton. There is currently a large variety of CBCT units on the market,1,2 and technical improvements are made continuously, such as the development of the field of view (FOV) from one fixed size to several sizes as well as stitched FOVs in the more recent models.The use of CBCT has increased dramatically, but published evidence supporting informed clinical decision-making is weak.1 As is the case with emerging healthcare technologies, it will take some time to produce evidence on the cost-effectiveness of CBCT for different diagnostic tasks including “costs” in terms of radiation dosages. Meanwhile, the use of CBCT and choice of scanning protocol has to rely on good practice related to the image quality needed for the actual diagnostic task and the amount of radiation exposure to the patient. The literature on dose levels of CBCT is, however, difficult to grasp and interpret owing to the diversity of CBCT units and different approaches taken in radiation dosimetry.The aim of this systematic review was to estimate the effective dose of CBCT of the facial skeleton with focus on measurement methods and scanning protocols used. Such a review can be beneficial when aiming to perform CBCT examinations with a radiation exposure as low as diagnostically acceptable (ALADA).3 A review may also highlight both strengths and weaknesses in study design to date and can thereby support sound study design in future research.  相似文献   
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