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991.
Cardiovascular risk stratification is currently part of routine clinical practice to establish cardiovascular prevention strategies. A complementary approach to the assessment scales of cardiovascular risk stratification is the non-invasive evaluation of the atherosclerotic lesion to identify patients at high risk for cardiovascular complications. Carotid intima-media thickness is a non-invasive method based on ultrasound suitable for the detection of subclinical atherosclerosis. It allows us to stratify cardiovascular risk beyond conventional cardiovascular risk factors and would complement the cardiovascular risk functions. The inclusion of the carotid intima-media thickness in cardiovascular risk stratification may help identify asymptomatic individuals with a high cardiovascular risk not detected by current scales of cardiovascular risk stratification.  相似文献   
992.
ObjectiveTo analyse the psychometric properties by a scale for evaluating patient centered clinical communication.DesignValidation and observational study of a measurement tool.SettingHealth centres and hospital outpatient clinics.ParticipantsThree researchers independently evaluated video recorded interviews of different sub-samples: health professionals (family medicine medical residents, family doctors, specialist care physicians, and primary care nurses), actual patients who consulted for chronic or acute health problems, and standardised patients.Primary measurementsDimensionality (exploratory factor analysis), internal consistency (alpha de Cronbach), intra- and inter-observer agreement (Kappa index, intraclass correlation coefficient [ICC], generalisability), sensitivity to change (Student t test) and convergent validity with the GATHA questionnaire (Pearson correlation coefficient).ResultsSix factors have been identified that explain 66.0% of the variance. The overall internal consistency of the test was α=0.94. The overall intra-observer agreement, measured with the ICC, varied between 0.94 and 0.97, whilst the inter-observer was between 0.82–0.90. The number of completed questionnaires required for the evaluator to obtain adequate reproducibility (generalisability) varied between 6 and 12. Statistical significance was not obtained when testing the sensitivity to change. The CICAA scale and the GATHA questionnaire had a correlation of 0.67.ConclusionsThe CICAA scale is a generic patient centered clinical communication evaluation tool that may be used in different clinical contexts and situations, since it has shown to be reliable, valid and efficient.  相似文献   
993.
Benign prostatic hyperplasia (BPH) is a high prevalence condition in men over 50 years that requires continued assistance between primary care and urology. Therefore, consensus around common referral criteria was needed to guide and support both levels. Medical history, symptom assessment with International Prostate Symptom Score (IPSS) questionnaire, digital rectal examination and prostate-specific antigen (PSA) measurement are diagnostic tests available for general practitioners that allow setting a correct BPH diagnose. Patients with an IPSS<8 should be monitored by evaluating them annually. Treatment with α-blockers and an evaluation at the first and third month is recommended in patients with an IPSS 8-20 and if the prostate is small, if the prostate size is large treatment with α-blockers or 5α-reductase inhibitors and evaluation at the third and six month is recommended, and in patients with a large prostate and a PSA >1.5 ng/ml combined treatment and evaluation at the first and sixth month is recommended. Some clear criteria for referral to urology are established in this document, which help in the management of these patients. Those patients with BPH who do not show any improvement at the third month of treatment with α-blockers, or the sixth month with 5α-reductase inhibitors, will be referred to urology. Patients will also be referred to urology if they have lower urinary tract symptoms, a pathological finding during rectal examination, IPSS>20, PSA>10 ng/ml or PSA>4 ng/ml and free PSA<20% or if they are <50 years with suspected BHP, or if they have any urological complication.  相似文献   
994.
995.
The aim of this work was to investigate those mechanical parameters able to describe the fracture behavior of dental composite resins. A commercially available fine-particle micro-hybrid resin composite was used. Classical parameters as Young's modulus, strength distribution, and critical stress intensity factor were considered. Strength values were determined using the diametrical compression of discs test and for the critical stress intensity factor both unstable and controlled fracture tests were used. Controlled fracture tests allowed determining the work of fracture. Microstructure was studied by optical and field emission scanning electron microscopy. The obtained properties have been Young's modulus, 17.7 +/- 0.6 GPa; Weibull modulus, m = 14 (upper and lower limits for 90% confidence: 17 and 10); characteristic strength 51 MPa (upper and lower limits for 90% confidence: 53 and 49 MPa); critical stress intensity factor in mode I, K(IC) = 1.3 +/- 0.1 and work of fracture, gamma(wof) = 8-9 J/m(2). Pores and bubbles formed during the packing of the composite were identified as critical defects in the tested specimens. Crack deflection and branching have been identified as toughening mechanisms. Classical mechanical parameters (Young's modulus, hardness...) are not able to efficiently predict the major clinical failure mode of composite resins by fatigue. Work of fracture analysis, which is dependant on microstructural parameters such as particle size and shape, have to be included when testing mechanical properties of dental composite resins in future research studies.  相似文献   
996.
Squamous cell carcinoma of the larynx is very rare in children and adolescents. It is usually diagnosed at late stages because early symptoms are often attributed to the maturation process or other common laryngeal pediatric diseases. Early visualization of vocal cords with fexible laryngoscopy is important in children presenting suggestive symptoms of laryngeal pathology. Defnitive diagnosis of carcinoma is made by biopsy, and juvenile laryngeal papillomatosis the most important differential diagnosis. Treatment constitutes a clinical challenge. There are no established protocols, and clinicians should make a special effort to preserve the functions of the larynx, and avoid long term complications. We present a 12-years-old child with invasive laryngeal carcinoma, without prior history of juvenile papillomatosis or radiotherapy, which responded favorably to chemotherapy and radiotherapy.  相似文献   
997.
In order to know the causes of death and the prognostic factors, our group analyzed 250 patients included until February 2005 in the web-site based international registry of patients with catastrophic antiphospholipid syndrome (APS) ("CAPS Registry") (http://www.med.ub.es/MIMMUN/FORUM/CAPS.HTM). Cerebral involvement, mainly consisting of stroke, followed by cardiac involvement and infections were considered the main causes of death in patients with catastrophic APS. The presence of systemic lupus erythematosus was related with higher mortality. According to the results of this analysis, anticoagulation plus steroids plus plasma exchange should be the first line of therapy in patients with catastrophic APS.  相似文献   
998.
The aim of this study is to investigate the association between three polymorphisms of the interleukin-1 (IL-1) gene complex and schizophrenia. We genotyped 228 outpatients with schizophrenia (DSM-IV criteria) and 419 unrelated healthy controls. The following polymorphisms were analyzed: IL-1alpha -889 C/T, IL-1beta +3953 C/T, and IL-1RA (86 bp)n. No significant differences in genotype or in allelic distribution of the Il-1alpha, IL-1beta, and IL-1RA polymorphisms were found. Estimated haplotype frequencies were similar in both groups. Our data do not suggest that genetically determined changes in the IL-1 gene complex confer increased susceptibility for schizophrenia.  相似文献   
999.
Hepatitis B is an important cause of morbidity and mortality around the world. One-third of the world's population has been estimated to be infected with hepatitis B virus (HBV). A significant amount of evidence suggests that both humoral and cellular immune responses are important to eliminate the virus and that, cellular immunity is involved in the pathogenesis of the disease. Vaccination with HBsAg is considered as the main strategy for effective control of the infection and viral transmission. However, approximately 5-10% of immunized individuals fail to elicit detectable specific antibodies and remain at risk for hepatitis B infection. In this work we have reviewed the current status in the pathogenesis of the disease and the mechanisms described to explain nonresponsiveness to the vaccine as well. Since nonresponders to the vaccine are at risk for the infection, a common mechanism to explain the absence or inappropriate immune response to virus components is proposed. Within the suggested model an impaired activation of T lymphocytes against viral antigens, both in nonresponders to vaccination and chronically infected patients, is described. These observations could be consistent with potential differences in the MHC/Ag presentation; therefore contributing to our understanding of the altered T helper response as an underlying mechanism for the lack of protective immunity against VHB.  相似文献   
1000.
OBJECTIVE: To study trends in progression to AIDS, all-cause mortality, and cause-specific mortality (AIDS-related, liver disease, and hemorrhagic complications) over calendar periods with different exposure to highly active antiretroviral therapy (HAART) in a cohort of hemophiliacs in Spain, taking into account the competing risks of the causes of death. METHODS: Multicenter cohort of HIV-infected hemophiliacs. HIV seroconversion was estimated using mathematic techniques for interval-censored data from 1979 through 1985. Rates of AIDS and cause-specific death were calculated by Poisson regression, allowing for late entry, for the periods 1985 through 1992, 1993 through 1996, 1997 through 2000 (early HAART), and 2001 through 2003 (late HAART), also allowing for competing risks. RESULTS: Of 585 subjects, 44% were younger than 15 years of age, 82% had severe hemophilia, 86% had type A hemophilia, and the median seroconversion date was October 1982. Calendar period and age at HIV seroconversion strongly influenced AIDS and death rates. Compared with 1993 through 1996, decreases of 75% (relative risk [RR] = 0.25, 95% confidence interval [CI]: 0.14 to 0.43) and 72% (RR = 0.28, 95% CI: 0.12 to 0.63) in the RR of AIDS were observed in early and late HAART. For all-cause mortality, 72% (RR = 0.28, 95% CI: 0.18 to 0.42) and 83% (RR = 0.17, 95% CI: 0.09 to 0.33) decreases were observed by 1997 through 2000 and 2001 through 2003. For liver-related deaths, increases were observed in the late-HAART period (RR = 2.80, 95% CI: 0.94 to 8.36) compared with 1993 through 1996, but using competing risks, this RR was substantially reduced (RR = 1.70, 95% CI: 0.57 to 5.04). DISCUSSION: Major reductions in AIDS and death rates were observed from 1997 to 2003 in hemophiliacs. These survival improvements are largely attributable to decreases in AIDS-related deaths and have been accompanied by increases in liver disease death rates, which are overestimated if competing risks are not taken into account.  相似文献   
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