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811.
Trisomy 3 in low-grade B-cell lymphomas of mucosa-associated lymphoid tissue   总被引:13,自引:3,他引:13  
Wotherspoon  AC; Finn  TM; Isaacson  PG 《Blood》1995,85(8):2000-2004
Characteristic chromosomal aberrations have been associated with subtypes of non-Hodgkin's lymphoma with distinct clinicopathologic features. Low-grade B-cell lymphomas of mucosa-associated lymphoid tissue (MALT) form such a group and might be expected to be characterized by a specific cytogenetic abnormality. Metaphase analyses of MALT lymphoma are rare due to problems with fresh tissue collection and poor in vitro proliferation. However, the small number of published series suggests that chromosome trisomies, particularly trisomy 3, might be characteristic of these tumors. The application of interphase cytogenetic techniques to routinely processed material allows the examination of a large series of archival cases and is particularly useful for the demonstration of chromosome trisomies. We have used this technique to analyze 70 cases of low-grade MALT lymphoma from various sites and found trisomy 3 in 60%. This finding compares with 16% in low- grade nodal B-cell lymphoma and 27% in primary splenic lymphoma of marginal zone type (splenic lymphoma with villous lymphocytes). These results provide further evidence that low-grade MALT lymphomas from all sites form a single pathologic entity distinct from nodal B-cell lymphomas. Although MALT lymphoma and primary splenic lymphoma may arise from marginal zone B cells, they are genetically distinct.  相似文献   
812.
One billion of the world's population has hypertension, resulting in four million deaths per year. Data on the prevalence of hypertension in the Arab world are very limited. This review summarizes existing knowledge regarding prevalence, awareness, and control of hypertension in Arab countries. The PubMed, Cochrane Library, Scopus, and CINAHL databases were searched for publications on HTN among Arab people from 1980 to January 2011. Only 13 studies were identified in the literature from 10 Arab countries. The overall estimated prevalence of hypertension was 29.5% (n = 45 379), which indicates a higher prevalence of hypertension among Arabs compared to people from the USA (28%) and sub‐Saharan African (27.6%). Awareness of hypertension was reported for 46% of the studies and varied from 18% (Jordan) to 79.8% (Syria). The control rate varied from 56% (Tunisia) to 92% (Egypt and Syria). The prevalence of hypertension was found to increase with age, occurring more frequently in Arab women.  相似文献   
813.

Objective

To describe India’s National Antimalarial Drug Resistance Monitoring System, measure the efficacy of first-line malaria treatments, and determine risk factors for treatment failure.

Methods

In 2009–2010, prospective studies with 28 days of follow-up were conducted at 25 sentinel sites. Patients infected with Plasmodium falciparum were given artesunate plus sulfadoxine-pyrimethamine (AS+SP); those infected with P. vivax were given chloroquine. Polymerase chain reaction was used to distinguish post-treatment reinfection from treatment failure. Isolates of P. falciparum were checked for dhfr and dhps mutations.

Findings

Overall, 1664 patients were enrolled. Kaplan–Meier survival analysis showed an efficacy of 98.8% for AS+SP. Most patients with P. falciparum parasitaemia cleared their parasitaemias within 24 hours of treatment initiation, but six, including four with treatment failure, remained parasitaemic after 72 hours. Double mutants in dhfr were found in 68.4% of the genotyped isolates. Triple or quadruple mutants in dhfr and mutations in dhps were rare. A daily dose of artesunate of < 3 mg per kg of body weight, age of less than 5 years, and fever at enrolment were associated with an increased risk of treatment failure. Chloroquine remained 100% efficacious and generally cleared P. vivax parasitaemias within 48 hours. Vomiting (seen in 47 patients) was the most common adverse event.

Conclusion

India’s National Antimalarial Drug Resistance Monitoring System provides wide coverage. The first-line antimalarials used in the country remain safe and efficacious. The treatment of malaria in young children and the relative benefits of age- and weight-based dosing need further exploration.  相似文献   
814.
815.
Rybicki  AC; Schwartz  RS; Hustedt  EJ; Cobb  CE 《Blood》1996,88(7):2745-2753
Band 3 (anion-exchange protein 1-[AE1]) is the major integral membrane protein of human erythrocytes and links the membrane to the underlying cytoskeleton via high-affinity binding to ankyrin. It is unclear whether other cytoskeletal proteins participate in strengthening the ankyrin-band 3 linkage, but a putative role for protein 4.2 (P4.2) has been proposed based on the increased osmotic fragility and spherocytic morphology of P4.2-deficient red blood cells (RBCs). The present study was designed to investigate the hypothesis that P4.2 has a direct role in strengthening the band 3-cytoskeleton linkage in human RBCs, by measuring independent features of this interaction in normal and P4.2- deficient RBCs. The features examined were the rotational mobility of band 3 assayed by time-resolved phosphorescence emission anisotropy (TPA), and the extractability of band 3 by octyl-beta-glucoside, the latter being a nonionic detergent that selectively extracts only band 3 that is not anchored to the cytoskeleton. We find that the amplitude of the most rapidly rotating population of band 3 (correlation time, approximately 30 to 60 microseconds) is increased 81% and 67% in P4.2- deficient ghosts (P4.2NIPPON and band 3MONTEFIORE, respectively) compared with control ghosts. The amplitude of the intermediate speed rotating population of band 3 (correlation time, approximately 200 to 500 microseconds) is increased 23% and 8% in P4.2-deficient ghosts (P4.2NIPPON and band 3MONTEFIORE, respectively) compared with control ghosts, at the expense of the slowly rotating component (correlation time, approximately 2,000 to 3,000 microseconds, amplitude decreased 43% and 39% in P4.2NIPPON and band 3MONTEFIORE, respectively) and immobile component (immobile on this experimental time scale; amplitude decreased 26% and 10% in P4.2NIPPON and band 3MONTEFIORE, respectively) of band 3. These results demonstrate that P4.2 deficiency partially removes band 3 rotational constraints, ie, it increases band 3 rotational mobility. The nonionic detergent octyl-beta-glucoside, which does not disturb band 3-cytoskeleton associations, ie, it extracts only band 3 that is not attached to the cytoskeleton, extracted 30% and 61% more band 3 from P4.2NIPPON and band 3MONTEFIORE ghost membranes, respectively, compared with control ghosts. The octyl-beta-glucoside ghost extracts from both P4.2-deficient phenotypes were enriched in band 3 oligomeric species (tetramers, higher-order oligomers, and aggregates) compared with controls. Since band 3 oligomers selectively associate with the cytoskeleton, these results are consistent with a weakened band 3-cytoskeleton linkage in P4.2-deficient RBC membranes. P4.2 deficiency does not affect band 3 anion transport activity, since uptake of radiolabeled sulfate was similar for control and P4.2- deficient RBCs. Thus, we propose that P4.2 directly participates in strengthening the band 3-cytoskeleton linkage.  相似文献   
816.
817.
<正>To the Editor: Hypoxic hepatitis(HH), also known as ischemic hepatitis or shock liver, is a liver injury characterized by necrosis of centrilobular hepatocytes with a rapid increase in serum aminotransferase levels. The incidence rate of HH among patients in the intensive care unit(ICU) was found to be 0.9%-11.9% [1]. Occurrence of HH appears to have a significant impact on the clinical outcome.  相似文献   
818.

Background

Feeding practices after neonatal and congenital heart surgery are complicated and variable, which may be associated with prolonged hospitalization length of stay (LOS). Systematic assessment of feeding skills after cardiac surgery may earlier identify those likely to have protracted feeding difficulties, which may promote standardization of care.

Methods

Neonates and infants ≤3 months old admitted for their first cardiac surgery were retrospectively identified during a 1‐year period at a single center. A systematic feeding readiness assessment (FRA) was utilized to score infant feeding skills. FRA scores were assigned immediately prior to surgery and 1, 2, and 3 weeks after surgery. FRA scores were analyzed individually and in combination as predictors of gastrostomy tube (GT) placement prior to hospital discharge by logistic regression.

Results

Eighty‐six patients met inclusion criteria and 69 patients had complete data to be included in the final model. The mean age of admit was five days and 51% were male. Forty‐six percent had single ventricle physiology. Twenty‐nine (42%) underwent GT placement. The model containing both immediate presurgical and 1‐week postoperative FRA scores was of highest utility in predicting discharge with GT (intercept odds = 10.9, P = .0002; sensitivity 69%, specificity 93%, AUC 0.913). The false positive rate was 7.5%.

Conclusions

In this analysis, systematic and standardized measurements of feeding readiness employed immediately before and one week after congenital cardiac surgery predicted need for GT placement prior to hospital discharge. The FRA score may be used to risk stratify patients based on likelihood of prolonged feeding difficulties, which may further improve standardization of care.  相似文献   
819.
820.
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