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141.
BACKGROUND: Community-acquired pneumonia (CAP) with a pneumonia severity index (PSI) score in risk class V (PSI-V) is a potentially life-threatening condition, yet the majority of patients are not admitted to the ICU. The aim of this study was to characterize CAP patients in PSI-V to determine the risk factors for ICU admission and mortality, and to assess the performance of CAP severity scores in this population. METHODS: Prospective observational study including hospitalized adults with CAP in PSI-V from 1996 to 2003. Clinical and laboratory data, microbiological findings, and outcomes were recorded. The PSI score; modified American Thoracic Society (ATS) score; the confusion, urea, respiratory rate, low BP (CURB) score, and CURB plus age of >/= 65 years score were calculated. A reduced score based on the acute illness variables contained in the PSI was also obtained. RESULTS: A total of 457 patients were included in the study (mean [+/- SD] age, 79 +/- 11 years), of whom 92 (20%) were admitted to the ICU. Patients in the ward were older (mean age, 82 +/- 10 vs 70 +/- 10 years, respectively) and had more comorbidities. ICU patients experienced significantly more acute organ failures. The mortality rate was higher in ICU patients, but also was high for non-ICU patients (37% vs 20%, respectively; p = 0,003). A low level of consciousness (odds ratio [OR], 3.95; 95% confidence interval [CI], 2 to 5) and shock (OR, 24.7; 95% CI, 14 to 44) were associated with a higher risk of death. The modified ATS severity rule had the best accuracy in predicting ICU admission and mortality. CONCLUSIONS: Most CAP patients PSI-V were treated on a hospital ward. Those admitted to the ICU were younger and had findings of more acute illness. The PSI performed well as a mortality prediction tool but was less appropriate for guiding site-of-care decisions.  相似文献   
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143.
This observational and clinical follow-up study involved the first 50 patients who were treated with the Janus tacrolimus-eluting carbostent (Sorin Group) at our hospital. The patients' mean age was 66 (10) years, 38% were diabetic, and 56% were admitted with acute coronary syndrome. In total, 56 lesions were treated (52% were type B2/C), of which 12% involved in-stent restenosis, 5% were chronic occlusions, 23% were long lesions (>20 mm), 25% were in small vessels (< or = 2.5 mm), 7% were aorto-ostial lesions, 5% were in vein grafts, and 14% involved angiographically visible thrombus. Some 63 Janus carbostents were implanted (i.e., 1.26 [0.49] stents/patient). A successful outcome was achieved for all lesions. One patient (2%) required reintervention at the target lesion because of acute thrombosis. During a follow-up period of 10 (3) months, eight (16%) major adverse cardiac events occurred: there was one (2%) death due to heart failure and seven patients (14%) required revascularization, in five (10%) cases because of restenosis of the Janus carbostent.  相似文献   
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The main risk factor for contrast nephropathy is the presence of poor renal function. Plasma creatinine level is not a reliable measure of renal function as its value could lie within the normal range despite the presence of significant nephropathy. The purpose of this study was to evaluate the creatinine clearance rate as a predictor of contrast nephropathy in patients with a normal plasma creatinine level. The study included 273 consecutive patients with non-ST elevation acute coronary syndrome (NSTEACS) and a normal plasma creatinine level at admission who underwent coronary angiography. Patients who developed contrast nephropathy had a lower creatinine clearance rate at admission (66.3 mL/min vs. 83.4 mL/min; P<.001). A creatinine clearance rate < 80 mL/min had a sensitivity of 81% for predicting contrast nephropathy. Creatinine clearance should be measured routinely in patients with NSTEACS who are scheduled for coronary angiography.  相似文献   
146.
Gap-junction channels connect the cytoplasm of adjacent cells, allowing the diffusion of ions and small metabolites. They are formed at the appositional plasma membranes by a family of related proteins named connexins. Mutations in connexins 26, 31, 30, 32, and 43 have been associated with nonsyndromic or syndromic deafness. The majority of these mutations are inherited in an autosomal recessive manner, but a few of them have been associated with dominantly inherited hearing loss. Mutations in the connexin26 gene (GJB2) are the most common cause of genetic deafness. This review summarizes the most relevant and recent information about different mutations in connexin genes found in human patients, with emphasis on GJB2. The possible effects of the mutations on channel expression and function are discussed, in addition to their possible physiologic consequences for inner ear physiology. Finally, we propose that connexin channels (gap junctions and hemichannels) may be targets for age-related hearing loss induced by oxidative damage.  相似文献   
147.

Introduction

Concurrent chemotherapy and radiotherapy is recommended for the treatment of locally advanced unresectable head and neck (H&N) cancer.

Objective

The primary purpose of the Phase I part of the study was to determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT) and recommended dose (RD) of docetaxel with hyperfractionation radiotherapy. The primary objective of the Phase II part was to determine the response rate to the RD of treatment and, secondarily, to assess the toxicity of the schedule, time to progression, duration of response and overall survival (OS).

Materials and methods

Patients (n=9 in Phase I; n=19 in Phase II) had unresectable H&N cancer. The starting docetaxel dose was 20 mg/m2 plus hyperfractionated radiotherapy. Ramping of docetaxel was 5 mg/m2 if MTD was not reached.

Results

MTD of docetaxel was 20 mg/m2. Limiting toxicities were grade 4 pneumonia and grade 4 mucositis. The RD was 15 mg/m2. Phase II initial response was 76% (CR=18%; PR=9%); updated response was 89% (CR=59%; PR=29%). The median progression-free survival was 7.8 months (95%CI: 0?C22.3) and the median OS was 15.1 months (95%CI: 0?C35.9). Grade 3?C4 toxicities included mucositis (91%), pneumonia (27%) and fatigue (27%). There were 5 toxic deaths (2 from intestinal perforation, 3 from pneumonia).

Conclusions

Weekly docetaxel+hyperfractionation radiotherapy is active but with high toxicity rates and, hence, this treatment regimen would be difficult to justify.  相似文献   
148.
To assess the expression of IGF-1R in oral cavity squamous cell carcinoma patients, to explore its relation with clinical and pathologic prognostic factors and its role in predicting clinical outcome. One hundred and thirty-one consecutive patients suffering from oral cavity squamous cell carcinoma were included in this study from July 1989 to April 2005. Follow-up was closed in May 2010. The mean follow-up for survivors was 110.26±47.42 months. Patients were staged following the TNM classification. Patients in tumour stages I and II were referred to surgery. Patients in stages III-IV were referred to postoperative radiotherapy. Radiation therapy was administered up to a mean dose of 62.13±7.74 Gy in 1.8-2 Gy fractions. IGF-1R expression was studied by immunohistochemistry in paraffin-embedded tumour tissue. IGF-1R was expressed in 101 patients (77.1%). IGF-1R expression was related to tumour grade (P=0.012). Tumour stage was the most important prognostic factor for survival. Low (negative and fairly) IGF-1R tumour expression was correlated to better long-term Local Disease Free Survival (P=0.016), Disease-Free Survival (P=0.029), and Survival (P=0.009) in patients achieving tumour stages III-IV. Low IGF-1R expression was related to better long-term control in patients suffering locally advanced oral carcinoma.  相似文献   
149.
Malignant tumors result from the accumulation of genetic alterations in oncogenes and tumor suppressor genes. Much less is known about the genetic changes in benign tumors. Seborrheic keratoses (SK) are very frequent benign human epidermal tumors without malignant potential. We performed a comprehensive mutational screen of genes in the FGFR3-RAS-MAPK and phosphoinositide 3-kinase (PI3K)-AKT pathways from 175 SK, including multiple lesions from each patient. SK commonly harbored multiple bona fide oncogenic mutations in FGFR3, PIK3CA, KRAS, HRAS, EGFR, and AKT1 oncogenes but not in tumor suppressor genes TSC1 and PTEN. Despite the occurrence of oncogenic mutations and the evidence for downstream ERK/MAPK and PI3K pathway signaling, we did not find induction of senescence or a DNA damage response. Array comparative genomic hybridization (aCGH) analysis revealed that SK are genetically stable. The pattern of oncogenic mutations and X chromosome inactivation departs significantly from randomness and indicates that spatially independent lesions from a given patient share a clonal relationship. Our findings show that multiple oncogenic mutations in the major signaling pathways involved in cancer are not sufficient to drive malignant tumor progression. Furthermore, our data provide clues on the origin and spread of oncogenic mutations in tissues, suggesting that apparently independent (multicentric) adult benign tumors may have a clonal origin.  相似文献   
150.
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