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1.
Severe middle vault deformity with disturbed nasal form and function is one of the most challenging procedures to correct in a secondary rhinoplasty. Reconstructing the deformity with autologous septal cartilage would be the primary choice of most surgeons, if it were always available. However in certain cases the lack of a sufficient quantity of autologous cartilage has forced surgeons to explore other viable options. This paper discusses our experience with the combined use of spreader and dorsal onlay grafts from various materials in the reconstruction of severe middle vault deformity in 110 patients. In follow up, (between 6 and 42 months; mean 21 months) all patients were noted to have improved in both aesthetics and function with no major complications noted. In summary, this study proposes that any engrafting material can be used safely when the proper surgical principals and technique are employed.  相似文献   
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Achromatopsia is an autosomal recessive disease of the retina, characterized clinically by an inability to distinguish colors, impaired visual acuity, nystagmus and photophobia. A genome-wide search for linkage was performed using an inbred Jewish kindred from Iran. To facilitate the genome-wide search, we utilized a DNA pooling strategy which takes advantage of the likelihood that the disease in this inbred kindred is inherited by all affected individuals from a common founder. Equal molar amounts of DNA from all affected individuals were pooled and used as the PCR template for short tandem repeat polymorphic markers (STRPs). Pooled DNA from unaffected members of the kindred was used as a control. A reduction in the number of alleles in the affected versus control pool was observed at several loci. Upon genotyping of individual family members, significant linkage was established between the disease phenotype and markers localized on chromosome 2. The highest LOD score observed was 5.4 (theta = 0). When four additional small unrelated families were genotyped, the combined peak LOD score was 8.2. Analysis of recombinant chromosomes revealed that the disease gene lies within a 30 cM interval which spans the centromere. Additional fine-mapping studies identified a region of homozygosity in all affected individuals, narrowing the region to 14 cM. A candidate gene for achromatopsia was excluded from this disease interval by radiation hybrid mapping. Linkage of achromatopsia to chromosome 2 is an essential first step in the identification of the disease-causing gene.   相似文献   
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The B-lymphocyte/accessory-cell activation antigen B7 (BB1) has been shown in vitro to stimulate T-lymphocyte proliferation and cytokine production via CD28 present on the latter cells. In this study, benign lymphoid tissues, lymphomas, and extralymphoid inflammatory sites were examined immunohistochemically using anti-B7 and other relevant monoclonal antibodies. B7 was expressed by benign transformed germinal center B cells, as it was by B cells of follicular lymphomas. B7 was also expressed by a subpopulation (a mean of 31% to 65%) of macrophages and dendritic cells in a variety of lymphoid tissues. It was present in abundance on all macrophages constituting sarcoid granulomas in lymph nodes. In extralymphoid inflammation, 17% to 35% of macrophages expressed B7 only weakly. Cases of Hodgkin's disease showed expression of B7 by the majority of Reed-Sternberg cells or malignant mononuclear variants, a phenomenon that potentially contributes to the lymphocytic accumulation that is a feature of this condition. CD28+ T cells were seen in all areas where T cells were present. B7+ and CD28+ cells colocalized in, for example, lymphoid follicles, lymph node paracortex, sarcoid granulomas, and Hodgkin's disease tissue, indicating a potential for cellular interaction via these molecules at these sites.  相似文献   
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Thrombotic microangiopathies (TMAs) are rare, but life-threatening disorders characterized by microangiopathic hemolytic anemia and thrombocytopenia (MAHAT) associated with multiorgan dysfunction as a result of microvascular thrombosis and tissue ischemia. The differentiation of the etiology is of utmost importance as the pathophysiological basis will dictate the choice of appropriate treatment.We retrospectively evaluated 154 (99 females and 55 males) patients who received therapeutic plasma exchange (TPE) due to a presumptive diagnosis of TMA, who had serum ADAMTS13 activity/anti-ADAMTS13 antibody analysis at the time of hospital admission. The median age of the study cohort was 36 (14-84). 67 (43.5%), 32 (20.8%), 27 (17.5%) and 28 (18.2%) patients were diagnosed as thrombotic thrombocytopenic purpura (TTP), infection/complement-associated hemolytic uremic syndrome (IA/CA-HUS), secondary TMA and TMA-not otherwise specified (TMA-NOS), respectively. Patients received a median of 18 (1­75) plasma volume exchanges for 14 (153) days. 81 (52.6%) patients received concomitant steroid therapy with TPE. Treatment responses could be evaluated in 137 patients. 90 patients (65.7%) achieved clinical remission following TPE, while 47 (34.3%) patients had non-responsive disease. 25 (18.2%) non-responsive patients died during follow-up. Our study present real-life data on the distribution and follow-up of patients with TMAs who were referred to therapeutic apheresis centers for the application of TPE.  相似文献   
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Percutaneous mitral valvuloplasty (PMV) was performed in 57 patients with mitral stenosis. Twenty-three women and 34 men (mean age 28 +/- 10 mean +/- SD) were included in the study. A single-balloon (trefoil or bifoil) technique was used in 49 patients and a double-balloon (trefoil + monofoil) technique in eight. After a 3-month follow-up period, right- and left-sided cardiac catheterization was repeated. In the single-balloon group there was improvement in the mitral valve gradient (16.10 +/- 5.99 to 4.41 +/- 2.03 mm Hg), mean left atrial pressure (22.65 +/- 6.13 to 9.76 +/- 3.01 mm Hg), and mitral valve area (0.89 +/- 0.22 to 1.95 +/- 0.46 cm2/m2). Mean pulmonary artery pressure and mean pulmonary wedge pressure decreased to 19.33 +/- 4.19 mm Hg and 10.73 +/- 2.60 mm Hg from 32.94 +/- 7.90 mm Hg and 21.49 +/- 5.98 mm Hg. Cardiac output increased to 6.86 +/- 0.56 L/min from 5.57 +/- 0.66. All improvements were statistically significant (p less than 0.001). In the double-balloon study group, mitral valve gradient (23.75 +/- 2.77 to 4.50 +/- 1.94 mm Hg), mean left atrial pressure (31.63 +/- 3.57 to 9.50 +/- 1.94 mm Hg), mean pulmonary artery pressure (44.00 +/- 6.36 to 18.88 +/- 7.10), and mean pulmonary wedge pressure (29.25 +/- 3.73 to 10.25 +/- 1.85 mm Hg) all improved significantly (p less than 0.001). Mitral valve area and cardiac output increased from 0.89 +/- 0.15 to 2.44 +/- 0.44 cm2/m2 (p less than 0.001) and from 5.46 +/- 0.76 to 7.15 +/- 0.52 L/min (p less than 0.002), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Proton pump inhibitors and H2 receptor antagonists, which are commonly used to treat peptic ulcer and gastroesophageal reflux diseases, are associated with a low incidence of adverse reactions. We report 3 cases of anaphylactic reactions induced by lansoprazole or ranitidine diagnosed in a population of 8304 first-referral patients over a 13-year period. Cutaneous sensitivity to famotidine, ranitidine, omeprazole, pantoprazole, and lansoprazole was evaluated by skin prick tests with a concentration of 10 mg/mL (at 1:1000, 1:100, 1:10 and 1:1 dilutions), and if they were negative, intradermal skin tests were performed with the same dilutions of the extracts. Single-blind, placebo-controlled oral provocation tests were performed with lansoprazole, omeprazole, famotidine, and ranitidine in 2 cases. One case involved anaphylaxis during an oral provocation test with lansoprazole, and 2 cases were anaphylactic reactions to ranitidine. In both cases the skin test was positive for ranitidine and in 1 case an oral provocation test was also positive. The second patient refused that test. Cross reactivity to other H2 receptor antagonists was not demonstrated and a safe alternative drug was found for all 3 patients. Although incidences of anaphylactic reactions induced by proton pump inhibitors or H2 reactions are rare, they can be life threatening.  相似文献   
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Hypertension is an important determinant of cardiovascular morbidity and mortality and has a substantial heritability, which is likely of polygenic origin. The aim of this study was to assess to what extent multiple common genetic variants contribute to blood pressure regulation in both adults and children and to assess overlap in variants between different age groups, using genome-wide profiling. Single nucleotide polymorphism sets were defined based on a meta-analysis of genome-wide association studies on systolic blood pressure and diastolic blood pressure performed by the Cohort for Heart and Aging Research in Genome Epidemiology (n=29 136), using different P value thresholds for selecting single nucleotide polymorphisms. Subsequently, genetic risk scores for systolic blood pressure and diastolic blood pressure were calculated in an independent adult population (n=2072) and a child population (n=1034). The explained variance of the genetic risk scores was evaluated using linear regression models, including sex, age, and body mass index. Genetic risk scores, including also many nongenome-wide significant single nucleotide polymorphisms, explained more of the variance than scores based only on very significant single nucleotide polymorphisms in adults and children. Genetic risk scores significantly explained ≤1.2% (P=9.6*10(-8)) of the variance in adult systolic blood pressure and 0.8% (P=0.004) in children. For diastolic blood pressure, the variance explained was similar in adults and children (1.7% [P=8.9*10(-10)] and 1.4% [P=3.3*10(-5)], respectively). These findings suggest the presence of many genetic loci with small effects on blood pressure regulation both in adults and children, indicating also a (partly) common polygenic regulation of blood pressure throughout different periods of life.  相似文献   
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