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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
941.
Laura Kropp Anish Baswanth Chakka Svetlana Yatsenko Eleonora Di Gregorio Daniela Lacerenza Giovanna Vaula Flavia Talarico Paola Mandich Camilo Toro Eleonore Eymard Pierre Pierre Labauge Sabina Capellari Pietro Cortelli Filippo Pinto Vairo Diego Miguel Danielle Stubbolo Lourenco Charles Marques William Gahl Odile Boespflug‐Tanguy Atle Melberg Sharon Hassin‐Baer Oren S. Cohen Rastislav Pjontek Armin Grau Thomas Klopstock Brent Fogel Inge Meijer Guy Rouleau Jean‐Pierre L. Bouchard Madhavi Ganapathiraju Adeline Vanderver Niklas Dahl Grace Hobson Alfredo Brusco Quasar Saleem Padiath 《Human mutation》2013,34(8):1160-1171
Autosomal dominant leukodystrophy (ADLD) is an adult onset demyelinating disorder that is caused by duplications of the lamin B1 (LMNB1) gene. However, as only a few cases have been analyzed in detail, the mechanisms underlying LMNB1 duplications are unclear. We report the detailed molecular analysis of the largest collection of ADLD families studied, to date. We have identified the minimal duplicated region necessary for the disease, defined all the duplication junctions at the nucleotide level and identified the first inverted LMNB1 duplication. We have demonstrated that the duplications are not recurrent; patients with identical duplications share the same haplotype, likely inherited from a common founder and that the duplications originated from intrachromosomal events. The duplication junction sequences indicated that nonhomologous end joining or replication‐based mechanisms such fork stalling and template switching or microhomology‐mediated break induced repair are likely to be involved. LMNB1 expression was increased in patients’ fibroblasts both at mRNA and protein levels and the three LMNB1 alleles in ADLD patients show equal expression, suggesting that regulatory regions are maintained within the rearranged segment. These results have allowed us to elucidate duplication mechanisms and provide insights into allele‐specific LMNB1 expression levels. 相似文献
942.
943.
N. Feldman A. Adler N. Molshatzki S. Navon-Venezia E. Khabra D. Cohen Y. Carmeli 《Clinical microbiology and infection》2013,19(4):E190-E196
The natural history of KPC-producing Klebsiella pneumoniae (KPC KP) carriage is unknown. We aimed to examine the duration of KPC KP carriage following hospital discharge and to study the risk factors for persistent carriage. A cohort of 125 KPC KP carriers was followed monthly for between 3 and 6 months after discharge from an acute-care hospital. Rectal swabs and data were collected at baseline and at each visit. KPC KP was detected by culture and direct blaKPC PCR. Acquisition time was regarded as the earliest date of KPC KP isolation. Resolution of carriage was defined as a negative KPC KP test in at least two consecutive samples. Analyses were separated for recent (<4 months) (REC, 75 patients) and remote (≥4 months) (REM, 50 patients) acquisition groups. Risk factors for persistent carriage were examined by survival analyses for the REC group and by prevalence methods for the REM group. The mean age of patients was 67.5 years and 49.6% were male. Forty-six (61%) patients in the REC group and 14 (28%) in the REM group were persistent carriers (p < 0.001). A significant risk factor for persistent carriage identified in both the REC and REM groups was the presence of any catheter (p < 0.05). Unique risk factor groups included long-term care facility (LTCF) residence (p < 0.01) and a low functional status as measured by the Barthel’s index (p < 0.05) in the REC group and high Charlson’s score in the REM group (p < 0.05). Out of the entire 100 patients who had at least one negative sample, only 65 remained negative on subsequent cultures. In conclusion, persistent carriage of KPC KP is associated with catheter use and a low functional status; it is more common in patients with recent acquisition and is related to LTCF stay. A single negative KPC KP test is insufficient to exclude persistent carriage. 相似文献
944.
945.
946.
Jeffrey F. Friedman Bipin Sunkara Jennifer S. Jehnsen Allison Durham Timothy Johnson Mark S. Cohen 《American journal of surgery》2015,210(6):1178-1184
Background
Secondary lymphedema is a frequent complication after lymphadenectomy in melanoma patients, although few studies in melanoma adequately characterize risk factors for lymphedema, and of these, sample size is limited. This study aims to identify risk factors associated with the lymphedema after axillary lymph node dissection (ALND) and inguinal lymph node dissection (ILND) in a more robust cohort of melanoma patients.Methods
We identified 269 ALND or ILND melanoma patients treated between 2008 and 2014. Demographic, clinical, and postoperative data were collected by review of the electronic medical record. Univariate and multivariate analysis were used to determine independent predictors of lymphedema.Results
Fifty-six (20.8%) of the patients developed lymphedema after lymph node dissection with a median staging group of 3. ILND (odds ratio [OR] = 4.506, P < .001, 95% confidence interval [CI]: 2.289 to 8.869) and peripheral vascular disease (PVD; OR = 3.849, P = .020, 95% CI: 1.237 to 11.975) were significant predictors of lymphedema in multivariate analysis. Obese body mass index approached significance (OR = 1.802, P = .069, 95% CI: .955 to 3.399).Conclusions
PVD and ILND were the 2 factors associated with the highest risk of lymphedema in melanoma surgery with PVD increasing risk 2-fold in ILND patients and 3-fold in ALND patients. These findings may improve surgeon-patient communication of care goals and surgical risk assessment. 相似文献947.
948.
Resveratrol reduces the levels of circulating androgen precursors but has no effect on,testosterone, dihydrotestosterone,PSA levels or prostate volume. A 4‐month randomised trial in middle‐aged men
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949.
Hypertension is almost universal in end‐stage renal disease (ESRD) and contributes to the substantial cardiovascular (CV) morbidity and mortality observed in these patients. The management of blood pressure (BP) in ESRD is complicated by a number of factors, including missed dialysis treatments, intradialytic changes in BP, medication removal with dialysis, and poor correlation of BPs obtained in the dialysis unit with those at home and with CV outcomes. Control of extracellular volume with ultrafiltration and dietary sodium restriction represents the principal strategy to manage hypertension in ESRD, and antihypertensive medications are subsequently added if this strategy is inadequate. While reduction in BP with medication improves CV outcomes, few head‐to‐head clinical trials have been performed to firmly establish the superiority of one antihypertensive medication class over another. Therefore, individualization of therapy is necessary, and patient comorbidities must be considered. Angiotensin‐converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and beta‐blockers are reasonable first‐line agents for most patients. ACE inhibitors and ARBs exert cardioprotective effects that are independent of BP reduction. Medications that are removed with dialysis may be preferred in patients who are prone to develop intradialytic hypotension. Intradialytic hypertension can be managed with challenging the patient's dry weight and using nondialyzable medications. Within a class of antihypertensive medications, there may be large variability in drug removal with dialysis, which must be considered upon medication selection. Studies demonstrate that even thrice‐weekly dosing of medication after dialysis has robust BP‐lowering effects, which may be a useful regimen in nonadherent patients. 相似文献
950.
Chen XJ Struzhkin VV Wu Z Somayazulu M Qian J Kung S Christensen AN Zhao Y Cohen RE Mao HK Hemley RJ 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(9):3198-3201
Detailed study of the equation of state, elasticity, and hardness of selected superconducting transition-metal nitrides reveals interesting correlations among their physical properties. Both the bulk modulus and Vickers hardness are found to decrease with increasing zero-pressure volume in NbN, HfN, and ZrN. The computed elastic constants from first principles satisfy c11 > c12 > c44 for NbN, but c11 > c44 > c12 for HfN and ZrN, which are in good agreement with the neutron scattering data. The cubic delta-NbN superconducting phase possesses a bulk modulus of 348 GPa, comparable to that of cubic boron nitride, and a Vickers hardness of 20 GPa, which is close to sapphire. Theoretical calculations for NbN show that all elastic moduli increase monotonically with increasing pressure. These results suggest technological applications of such materials in extreme environments. 相似文献