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131.
Chronic bronchitis (CB) is an indicator of an increased risk of developing COPD, but its symptoms are often underestimated. Demographic and socio-economic conditions might influence its prevalence, reporting and impact. Data from a large epidemiological survey of the French general population were analyzed to determine the burden of CB, the magnitude of under-diagnosis and the influence of age, gender and socio-economic conditions. Altogether, 9050 participants aged 45 years or more provided complete data. The prevalence of symptoms and diagnosis of CB was 3.5% and 3.4%, respectively. CB was associated with impaired health status and activity and, in women, work loss. Among subjects with symptoms of CB, only 28.6% declared a known diagnosis of respiratory disease. Factors associated with symptoms of CB in multivariate analysis were male gender, active smoking, lower income and occupational category: the highest prevalence was observed in manual workers (5.6%) and self-employed subjects (5.2%). The under-diagnosis of CB was more marked in men and subjects of higher socio-economic categories. These results confirm that CB is markedly under-diagnosed in the general population. Socio-economic conditions influence both its prevalence (higher in low categories) and rate of diagnosis (lower in high categories), which should be considered when elaborating prevention and detection campaigns.  相似文献   
132.
133.
BackgroundWhether myocardial recovery occurs more frequently in peripartum cardiomyopathy (PPCM) than in recent onset cardiomyopathies in men and nonperipartum women has not been prospectively evaluated. This was examined through an analysis of outcomes in the Intervention in Myocarditis and Acute Cardiomyopathy 2 (IMAC2) registry.Methods and ResultsIMAC2 enrolled 373 subjects with recent onset nonischemic dilated cardiomyopathy. Left ventricular ejection fraction (LVEF) was assessed at entry and 6 months, and subjects followed for up to 4 years. Myocardial recovery was compared between men (group 1), nonperipartum women (group 2) and subjects with PPCM (group 3). The cohort included 230 subjects in group 1, 104 in group 2, and 39 in group 3. The mean LVEF at baseline in groups 1, 2, and 3 was 0.23 ± 0.08, 0.24 ± 0.08, and 0.27 ± 0.07 (P = .04), and at 6 months was 0.39 ± 0.12, 0.42 ± 0.11, and 0.45 ± 0.14 (P = .007). Subjects in group 3 had a much greater likelihood of achieving an LVEF >0.50 at 6 months than groups 1 or 2 (19 %, 34%, and 48% respectively, P = .002).ConclusionsProspective evaluation confirms myocardial recovery is greatest in women with PPCM, poorest in men, and intermediate in nonperipartum women. On contemporary therapy, nearly half of women with PPCM normalize cardiac function by 6 months.  相似文献   
134.
Colorimetric and fluorescent probes based on small organic molecules have become important tools in modern biology because they provide dynamic information concerning the localization and quantity of the molecules and ions of interest without the need for genetic engineering of the sample. In the past five years, these probes for ions and molecules have attracted great attention because of their biological, environmental and industrial significance combined with the simplicity and high sensitivity of absorption and fluorescence techniques. Moreover, pyrazole derivatives display a number of remarkable photophysical properties and wide synthetic versatility superior to those of other broadly used scaffolds. This review provides an overview of the recent (2016–2020) findings on chemosensors containing pyrazole derivatives (pyrazoles, pyrazolines and fused pyrazoles). The discussion focuses on the design and physicochemical properties of chemosensors in order to realize their full potential for practical applications in environmental and biological monitoring (sensing of metal ions, anions, explosives, and biomolecules). We also present our conclusions and outlook for the future.

This review provides an overview on the recent (2016–2020) findings on chemosensors based on pyrazole derivatives. The discussion focuses on the design, physicochemical properties and practical applications of probes.  相似文献   
135.
In experimental studies, statin use has been associated with reduction of osteoclastic activity and promotion of bone formation around implants. Moreover, a large clinical study recently reported a substantially reduced risk of revision for aseptic loosening among statin users with THA. Our objective was to evaluate the influence of statin use on the development of femoral osteolysis within 5 years after THA. We conducted a case‐cohort study including all THAs presenting with femoral osteolysis at the 5 year visit (cases) and compared them with those without osteolysis (controls). Cases and controls were identified from a cohort of primary THAs operated between 2001 and 2005. Seven hundred thirty‐five THAs were included, mean age 68 years. Five years after surgery osteolysis had developed around the femoral component of 40 THAs (5.4%). Ever‐use of statins was much less frequent among cases (5 of 40, 12.5%) than among controls (199 of 695, 28.6%). The crude risk ratio of femoral osteolysis among statin users was 0.36 (95% CI 0.14; 0.92). After adjusting for age, sex, activity level, BMI, diagnosis, bearing surface, and type of stem, the adjusted risk ratio was 0.38 (95% CI 0.15; 0.99). In conclusion, statin use was associated with a reduced risk of developing femoral osteolysis 5 years after THA. Statins may be useful for reducing the risk of implant failure following THA. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 814–820, 2013  相似文献   
136.

Purpose

Empirical broad-spectrum antibiotic treatment for orthopaedic implant infections after surgical lavage is common practice while awaiting microbiological results, but lacks evidence.

Methods

This was a single-centre cohort study from 1996 to 2010 with a follow-up of two years.

Results

We retrieved 342 implant infections and followed them up for a median of 3.5 years (61 recurred, 18 %). Infected implants were arthroplasties (n = 186), different plates, nails or other osteosyntheses. The main pathogens were S. aureus (163, 49 methicillin-resistant) and coagulase-negative staphylococci (60, 45 methicillin-resistant). Median duration of empirical antibiotic coverage after surgical drainage was three days before switching to targeted therapy. Vancomycin was the most frequent initial empirical agent (147), followed by intravenous co-amoxiclav (44). Most empirical antibiotic regimens (269, 79 %) proved sensitive to the causative pathogen, but were too broad in 111 episodes (32 %). Cephalosporins and penicillins were used only in 44 and ten cases, respectively, although they would have covered 59 % of causative pathogens identified later. Multivariate Cox regression analysis showed that neither susceptible antibiotic coverage (compared to non-susceptible; hazard ratio 0.7, 95 % confidence interval 0.4–1.2) nor broad-spectrum use (hazard ratio 1.1, 0.8–1.5) changed remission rates.

Conclusions

Provided that surgical drainage is performed, broad-spectrum antibiotic coverage does not enhance remission of orthopaedic implant infections during the first three days. If empirical agents are prescribed from the first day of infection, narrow-spectrum penicillins or cephalosporins can be considered to avoid unnecessary broad-spectrum antibiotic use.  相似文献   
137.
BackgroundMedically based efforts and alternative treatment strategies to prevent or remediate the corrosive effects of radiotherapy on pathologic fracture healing have failed to produce clear and convincing evidence of success. Establishing an effective pharmacologic option to prevent or treat the development of non-unions in this setting could have immense therapeutic potential. Experimental studies have shown that deferoxamine (DFO), an iron-chelating agent, bolsters vascularity and subsequently enhances normal fracture healing when injected locally into a fracture callus in long bone animal models. Since radiotherapy is known to impede angiogenesis, we hypothesized that the pharmacologic addition of DFO would serve to mitigate the effects of radiotherapy on new vessel formation in vitro and in vivo.Materials and MethodsIn vitro investigation of angiogenesis was conducted utilizing HUVEC cells in Matrigel. Endothelial tubule formation assays were divided into four groups: Control, Radiated, Radiated + Low-Dose DFO and Radiated + High-Dose DFO. Tubule formation was quantified microscopically and video recorded for the four groups simultaneously during the experiment. In vivo, three groups of Sprague–Dawley rats underwent external fixator placement and fracture osteotomy of the left mandible. Two groups received pre-operative fractionated radiotherapy, and one of these groups was treated with DFO after fracture repair. After 40 days, the animals were perfused and imaged with micro-CT to calculate vascular radiomorphometrics.ResultsIn vitro, endothelial tubule formation assays demonstrated that DFO mitigated the deleterious effects of radiation on angiogenesis. Further, high-dose DFO cultures appeared to organize within 2 h of incubation and achieved a robust network that was visibly superior to all other experimental groups in an accelerated fashion. In vivo, animals subjected to a human equivalent dose of radiotherapy (HEDR) and left mandibular fracture demonstrated quantifiably diminished μCT metrics of vascular density, as well as a 75% incidence of associated non-unions. The addition of DFO in this setting markedly improved vascularity as demonstrated with 3D angiographic modeling. In addition, we observed an increased incidence of bony unions in the DFO treated group when compared to radiated fractures without treatment (67% vs. 25% respectively).ConclusionOur data suggest that selectively targeting angiogenesis with localized DFO injections is sufficient to remediate the associated severe vascular diminution resulting from a HEDR. Perhaps the most consequential and clinically relevant finding was the ability to reduce the incidence of non-unions in a model where fracture healing was not routinely observed.  相似文献   
138.
Of the 74 immunocompetent patients diagnosed between July 2004 and June 2011 at the North Shore University Hospital and Long Island Jewish Medical Center with primary central nervous system lymphoma, 71 (95.9%) had diffuse large B-cell lymphomas (DLBCL). The median patient age was 68 years (range: 19–87 years) with a slight male preponderance (1.1:1). The overall median survival time was 21 months. For patients older than 70 years, the median survival time was 8 months while for those 70 years or younger, the median survival time was 27 months (p < 0.01). Female patients had a worse prognosis than male patients (p < 0.05, median survival time, 17 months compared to 23 months). We had enough data from 52 of these 71 patients to define the lymphomas as either germinal center B-cell-like (GCB) or activated B-cell-like (ABC) DLBCL. Of these 52 patients, 42 (80.8%) had ABC DLBCL while only 10 (19.2%) had GCB DLBCL. The patients in the GCB subgroup seemed to survive longer than the patients in the ABC subgroup, although the difference did not reach statistical significance. No statistically significant difference in overall survival was seen between patients with BCL-6 positive or negative DLBCL; or between patients with BCL-2 positive or negative DLBCL.  相似文献   
139.
Specialists in dento-facial orthopedics have a large range of dental radiological techniques at their disposal to help them in their diagnostic and therapeutic procedures. Peri-apical, occlusal, panoramic, and cephalometric X-Rays are two-dimensional techniques that orthodontists can complement, if necessary, with Multi slices CT scan or Cone Beam Computed Tomography. Orthodontists must apply and respect quality criteria for each type of film in order to derive the best information from every image and to avoid producing artifacts or false images that will reduce their diagnostic value and, accordingly, the service that they render to patients. Practitioners must be willing to spend the few moments it takes to position patients correctly in the radiological apparatus instead of taking multiple views to compensate for failing to scrupulously follow protocols of radiology.  相似文献   
140.
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