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In brief: Marian's syndrome has gained increased attention and interest recently, more so since the death of volleyball star Flo Hyman last January. The disorder was first described by French pediatrician Antoine Bernard-Jean Marfan in 1896, although it may not have been the same syndrome as we know it today. Current thought suggests a defect in collagen—the fibrous material found in bones, joints, eyes, heart, and blood vessels. Positive diagnosis requires the presence of at least two of four major features: a positive family history and ocular, cardiac, and skeletal abnormalities. This article reviews the disease and discusses methods of detection and management.  相似文献   
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The aims of the present study were (i) to assess the in vitro genetic stability of S19 and RB51 Brucella abortus vaccines strains and (ii) to evaluate the ability of multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) as a tool to be used in the quality control of live vaccines against brucellosis. Sixty-three batches of commercial S19 (n = 53) and RB51 (n = 10) vaccines, produced between 2006 and 2009, were used in this study. S19 and RB51 vaccines were obtained from, respectively, seven and two different manufacturers. Ten in vitro serial passages were performed on reference strains and on selected batches of commercial vaccines. All batches, reference strains and strains of serial passages were typed by the MLVA16. The results demonstrated that B. abortus S19 and RB51 vaccine strains are genetically stable and very homogeneous in their respective groups. Anyway, batches of S19 from one manufacturer and batches of RB51 from another presented genotypes distincts from the reference vaccine strains. In both cases, differences were found on locus Bruce07, which had addition of one repeat unit in the case of S19 batches and the deletion of one repeat unit in the case of RB51 batches. In summary, MLVA16 proved to be a molecular tool capable of discriminating small genomic variations and should be included in in vitro official tests.  相似文献   
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Background

Laparoscopic cholecystectomy (LC) is the standard operative intervention for gallbladder disease. Complications may necessitate conversion to an open cholecystectomy (OC). This study aims to determine the cost-consequences of laparoscopic-to-open conversion using a nationally-representative sample.

Methods

Using the National Inpatient Sample (2007–2011), adult patients undergoing emergent LC were identified. Patients undergoing secondary-conversion to OC were subsequently identified. Multivariable regression analyses, accounting for differences in propensity-quintile, mortality, length of stay, and hospital-level factors were then performed to assess for differences in the odds of conversion and total predicted mean costs per index-hospitalization.

Results

Of 225,805 observations, conversion to open occurred in 1.86% (n?=?4203) of cases. Increased age, African-American ethnicity, public-insurance and teaching-hospital status were associated with a higher likelihood of conversion (p?<?0.05) after risk-adjustment. Risk-adjusted odds of conversion increased by 34% (95%CI:1.33–1.36) for each day surgery was delayed. Risk-adjusted costs, were 259% higher (absolute-difference $23,358,p?<?0.05) with conversion. Mortality was higher amongst patients undergoing conversion to open (4.98% vs 0.34%,p?<?0.001).

Conclusion

Patients undergoing conversion from laparoscopic to open cholecystectomy are at an increased risk of receiving disparate care and increased mortality.  相似文献   
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