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1.
Clinical Rheumatology - Prof. Ari Polachek on of the author of the published version of this article missed to add his second affiliation which is the Department of Rheumatology, Tel Aviv Sourasky...  相似文献   
2.
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones.  相似文献   
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Job-exposure matrices were constructed and applied in the estimation of past exposures in a case-referent study nested within a cohort of Finnish woodworkers. The objective was to avoid bias in the risk estimates because of a misclassification of exposures. The matrices were constructed separately for each plant under study and each calendar year of follow-up. The level of exposure was incorporated in the matrices, since rather comprehensive data on exposures were available. The individual work histories were converted to exposure histories by a computer program which calculated several exposure indicators (eg, level and dose, with and without allowance for a latency period). The comparison between several indicators was thought to provide additional information for the final evaluation of results. The use of the plant- and period-specific job exposure matrices may be considered in cohort and nested case-referent studies on occupational hazards as an alternative to other procedures used in the estimation of exposures. Specific matrices may find broader applicability along with the increasing availability of detailed hygienic data.  相似文献   
5.
In order to evaluate the correlation between mobility and percussion sound, 126 upper incisors and canines in 21 student volunteers were measured by means of the Periotest (Siemens), by evaluating the percussion sound subjectively and by analyzing its spectrum. The attenuation time and frequency of the sound were measured for each tooth. A logical mobility and percussion sound existed in accordance with the sizes of the teeth. Spearman correlation coefficients close to 1.00 were noted in individual cases between the Periotest and the three other tests describing the percussion sounds.  相似文献   
6.
In the present study the contribution of cytoplasmic polypeptides thymosins beta 4 and beta 10 to the 1H NMR spectrum during the maturation of the rat cerebral cortex was assessed. In the proton spectrum intense broad peaks at 0.9, 1.22, and 1.40 ppm from thymosins decreased in size relative to the signal at 2.02 ppm in parallel to the reciprocal increase in the concentration of N-acetyl aspartate. Levels of thymosins beta 4 and beta 10 were under developmental regulation. It is concluded that peaks from thymosins may provide extended information for an NMR spectroscopist and thus they have to be taken into account in the interpretation of the newborn cerebral 1H NMR spectrum.  相似文献   
7.
CCR5Delta32 is a deletion mutation in the chemokine receptor CCR5. Liver inflammatory activity was found to be significantly reduced (P = 0.005) in Jewish Israeli patients infected with the hepatitis C virus (HCV) carrying the CCR5Delta32 allele. The CCR5Delta32 allele does not alter susceptibility to HCV infection; however, it may play a role in the progression and outcome of the disease.  相似文献   
8.
Electrically conducting soluble polyaniline (PANI), containing different amounts of a bulky lipophilic cationic additive, tridodecylmethylammonium chloride (TDMACl), was studied by Raman (λexc=780 nm) and UV–vis spectroscopy. PANI was made simultaneously electrically conducting and soluble with bis[4-(1,1,3,3-tetramethylbutyl)phenyl]phosphoric acid in dichloromethane. The PANI membranes were prepared by drop casting on glassy carbon or ITO substrates. Raman and UV–vis measurements were carried out in a 0.1 M CaCl2 solution at potentials between 400 and ?600 mV (vs. SCE) at pH 6, or alternatively at the open circuit potential at pH 10. The results of Raman, UV–vis and cyclic voltammetric measurements confirm that the incorporation of TDMACl into the PANI membrane facilitates the oxidation and reduction of PANI.  相似文献   
9.
Computed tomography (CT) after abdominoperineal (AP) resection for rectal carcinoma is a routine procedure for the detection of recurrent tumor and distal metastases. We reviewed sequential CT scans after AP resection in 52 patients in order to see whether the urinary tract as a neighboring organ is involved in recurrent malignancy. Bladder displacement in itself was not associated with hydronephrosis. Such hydronephrosis developed, however, in 14 patients--13 with a presacral mass, and one with retroperitoneal lymphadenopathy. In 23 of the 52 patients a presacral mass appeared, either fibrosis, infection, or recurrence. Severe hydronephrosis was found only with malignancy. We suggest that marked hydronephrosis associated with a presacral mass after AP resection is an indirect sign of malignancy.  相似文献   
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