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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   
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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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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   
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BACKGROUND: Severe ulcerative colitis is potentially life threatening even though a policy of intensive medical management and early colectomy in recent years reduced mortality to almost zero. However, colectomy, with or without ileal-anal anastomosis, has its own problems (morbidity, pouchitis, cuffitis) and no reliable prognostic index of surgical outcome has been developed. Intravenous steroids are still the mainstay of medical therapy but their maximal duration before stating a 'treatment failure' has not been defined. AIM OF THE STUDY: To evaluate the effectiveness, safety and outcome of an intensive medical approach in a series of patients with severe ulcerative colitis. PATIENTS AND METHODS: One hundred and forty-nine episodes of severe ulcerative colitis in 115 patients admitted to a Gastroenterology Unit in a 7-year period were retrospectively evaluated. Intravenous glucocorticosteroids--methylprednisolone 1 mg/kg/day--and topical steroids were administered, and supportive treatments with intensive monitoring were extended to all the patients. Second-line strategies for steroid-refractoriness were prolonged glucocorticosteroids treatment, oral ciclosporin, infliximab or surgery. RESULTS: The median number of Truelove criteria at admission was 3 (range 2-5), median CRP 34 mg/l (range 10-196). Median follow-up after discharge was 49 months. In 84 (57%) episodes an early response was noted, while 65 (43%) did not respond within 10 days to the standard steroid treatment. In the non-responders group, 28 patients went into remission with a prolonged steroid treatment (slow responders); 15 patients were treated with ciclosporin (eight responders) and 6 with infliximab (four responders). A total of 24 colectomies was performed in this group of patients (in 21 cases within 30 days from admission). Slow responders showed lower albumin levels (P = 0.02), higher cumulative dose of glucocorticosteroids in the year prior to admission (P = 0.02) and higher age (P = 0.03), in comparison with early responders. Major complications were noted in four episodes which responded to medical treatment. Disease-related mortality was zero. CONCLUSIONS: Medical treatment and use of second-line therapies were effective in the present series of patients. A group of slow responders has been identified and, if an intensive medical monitoring is guaranteed, steroids can be safely prolonged after the first 10 days of treatment. Cumulatively, about 80% of the patients responded to short-term medical treatment, only 5% of the patients underwent colectomy in the follow-up period. Major adverse events were recorded in four patients, who had recovered completely after adequate medical treatment.  相似文献   
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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   
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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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Chiari I malformation (CM) associated with a cervico-thoracic syrinx due to supracerebellar arachnoid cyst has not been reported in the literature. We report such a case, managed by fenestration of the arachnoid cyst and foramen magnum decompression (FMD), aiming to reduce the inferiorly directed pressure on the cerebellum and eliminate the craniospinal pressure dissociation respectively. Imaging done post-operatively showed upward displacement of the cerebellar tonsils with a decompressed craniovertebral junction and disappearance of the syrinx.  相似文献   
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