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991.
992.
Quantification of retinal transneuronal degeneration in human glaucoma: a novel multiphoton-DAPI approach 总被引:2,自引:0,他引:2
Lei Y Garrahan N Hermann B Becker DL Hernandez MR Boulton ME Morgan JE 《Investigative ophthalmology & visual science》2008,49(5):1940-1945
PURPOSE: Glaucoma is presumed to result in the selective loss of retinal ganglion cells. In many neural systems, this loss would initiate a cascade of transneuronal degeneration. The quantification of changes in neuronal populations in the middle layers of the retina can be difficult with conventional histologic techniques. A method was developed based on multiphoton imaging of 4',6'-diamino-2-phenylindole (DAPI)-stained tissue to quantify neuron loss in postmortem human glaucomatous retinas. METHODS: Retinas from normal and glaucomatous eyes fixed in 4% paraformaldehyde were incubated at 4 degrees C overnight in DAPI solution. DAPI-labeled neurons at different levels of the retina were imaged by multiphoton confocal microscopy. Algorithms were developed for the automated identification of neurons in the retinal ganglion cell layer (RGCL), inner nucleus layer (INL), and outer nuclear layer (ONL). RESULTS: In glaucomatous retinas, the mean density of RGCs within 4 mm eccentricity was reduced by approximately 45%, with the greatest RGC loss occurring in a region that corresponds to the central 6 degrees to 14 degrees of vision. Significant neuron loss in the INL and ONL was also seen at 2 to 4 mm and 2 to 3 mm eccentricities, respectively. The ratios of neuron densities in the INL and ONL relative to the RGCL (INL/RGC and ONL/RGC, respectively) were found to increase significantly at 3 to 4 mm eccentricity. CONCLUSIONS: The data confirm that the greatest neuronal loss occurs in the RGCL in human glaucoma. Neuronal loss was also observed in the outer retinal layers (INL and ONL) that correlated spatially with changes in the RGCL. Further work is necessary to confirm whether these changes arise from transneuronal degeneration. 相似文献
993.
The relationship of circulating relaxin‐2 concentrations with short‐term prognosis in patients with acute heart failure: the RELAHF study
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994.
Follow‐up of surgically treated patients with cystic echinococcosis: can novel recombinant antigens compete with imaging? Analysis of a patient cohort
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995.
996.
Nicolás Roberto Robles MD PhD Roman Hernandez‐Gallego MD Francesco Fici MD PhD Guido Grassi MD PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2017,19(8):764-770
Aggressive reduction of blood pressure may increase cardiovascular events (the J‐curve phenomenon) in certain populations. In this regard, most studies in patients with chronic kidney disease have shown a J curve for cardiovascular morbidity and mortality, and this phenomenon persists after adjusting for confounding factors. Since there is no evidence that a straighter blood pressure target (<130/70 mm Hg) could improve renal outcomes, the increased cardiovascular risk associated with extreme blood pressure reduction should be seen as undesirable. Moreover, the intensive control of blood pressure may induce an unintended reduction of renal function and this decrease, in turn, may increase cardiovascular risk. 相似文献
997.
Linda L Wong Brenda Y Hernandez Yurii B Shvetsov Yoichi Kawano Zhao-You Tang Jun-Fang Ji 《World journal of hepatology》2016,8(31):1327-1335
AIM To compare patients who underwent resection of early stage hepatocellular cancer(HCC) in three different countries. METHODS This retrospective study characterizes 573 stage Ⅰ/Ⅱ HCC patients treated with liver resection in 3 tertiaryreferral centers: Tokyo(n = 250), Honolulu(n = 146) and Shanghai(n = 177).RESULTS Shanghai patients were younger, predominantly male, hepatitis-B seropositive(94%) and cirrhotic(93%). Tokyo patients were older and more likely to have hepatitis-C(67%), smaller tumors, low albumin, and normal alpha-fetoprotein. The Honolulu cohort had the largest tumors and 30% had no viral hepatitis. Ageadjusted mortality at 1 and 5-years were lower in theTokyo cohort compared to Honolulu and there was no difference in mortality between Shanghai and Honolulu cohorts. Elevated alpha-fetoprotein, low albumin and tumor 5 cm were associated with increased 1-year mortality. These factors and cirrhosis were independently associated with increased 5-year mortality. Independent risk factors of survival varied when examined separately by center. CONCLUSION The profile of early-stage HCC patients is strikingly different across countries and likely contributes to survival differences. Underlying differences in patient populations including risk factors/comorbidities influencing disease progression may also account for variation in outcomes. 相似文献
998.
FISHing in the dark: How the combination of FISH and conventional karyotyping improves the diagnostic yield in CpG‐stimulated chronic lymphocytic leukemia
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Adrian M. Dubuc Matthew S. Davids Mirela Pulluqi Olja Pulluqi Kevin Hoang Jesus M. Hernandez‐Sánchez Cathy Schlich Jesus M. Hernández‐Rivas Jennifer R. Brown Paola Dal Cin 《American journal of hematology》2016,91(10):978-983
Despite significant advances in molecular genetic approaches, fluorescence in situ hybridization (FISH) remains the gold standard for the diagnostic evaluation of genomic aberrations in patients with chronic lymphocytic leukemia (CLL). Efforts to improve the diagnostic utility of molecular cytogenetic testing have led to the expansion of the traditional 4‐probe CLL FISH panel. Not only do these efforts increase the cost of testing, they remain hindered by the inherent limitations of FISH studies ‐ namely the inability to evaluate genomic changes outside of the targeted loci. While array‐based profiling and next generation sequencing (NGS) have critically expanded our understanding of the molecular pathogenesis of CLL, these methodologies are not routinely used by diagnostic laboratories to evaluate copy number changes or the mutational profile of this disease. Mitogenic stimulation of CLL specimens with CpG‐oligonucleotide (CpG‐ODN) has been identified as a reliable and reproducible means of obtaining a karyotype, facilitating a low‐resolution genome‐wide analysis. Across a cohort of 1255 CpG‐ODN‐stimulated CLL specimens, we describe the clinical utility associated with the combinatorial use of FISH and karyotyping. Our testing algorithm achieves a higher diagnostic yield (~10%) through the detection of complex karyotypes, well‐characterized chromosomal aberrations not covered by the traditional CLL FISH panel and through the detection of concurrent secondary malignancies. Moreover, the single cell nature of this approach permits the evaluation of emerging new clinical concepts including clonal dynamics and clonal evolution. This approach can be broadly applied by diagnostic laboratories to improve the utility of traditional and molecular cytogenetic studies of CLL. Am. J. Hematol. 91:978–983, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
999.
Incremental cost of implementing residual insecticide treatment with delthametrine on top of intensive routine Aedes aegypti control
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1000.
Sterile Fluid Collections in Acute Pancreatitis: Catheter Drainage Versus Simple Aspiration 总被引:4,自引:0,他引:4
Walser EM Nealon WH Marroquin S Raza S Hernandez JA Vasek J 《Cardiovascular and interventional radiology》2006,29(1):102-107
Purpose To compare the clinical outcome of needle aspiration versus percutaneous catheter drainage of sterile fluid collections in
patients with acute pancreatitis.
Methods We reviewed the clinical and imaging data of patients with acute pancreatic fluid collections from 1998 to 2003. Referral
for fluid sampling was based on elevated white blood cell count and fevers. Those patients with culture-negative drainages
or needle aspirations were included in the study. Fifteen patients had aspiration of 10–20 ml fluid only (group A) and 22
patients had catheter placement for chronic evacuation of fluid (group C). We excluded patients with grossly purulent collections
and chronic pseudocysts. We also recorded the number of sinograms and catheter changes and duration of catheter drainage.
The CT severity index, Ranson scores, and maximum diameter of abdominal fluid collections were calculated for all patients
at presentation. The total length of hospital stay (LOS), length of hospital stay after the drainage or aspiration procedure
(LOS-P), and conversions to percutaneous and/or surgical drainage were recorded as well as survival.
Results The CT severity index and acute Ransom scores were not different between the two groups (p = 0.15 and p = 0.6, respectively). When 3 crossover patients from group A to group C were accounted for, the duration of hospitalization
did not differ significantly, with a mean LOS and LOS-P of 33.8 days and 27.9 days in group A and 41.5 days and 27.6 days
in group C, respectively (p = 0.57 and 0.98, respectively). The 60-day mortality was 2 of 15 (13%) in group A and 2 of 22 (9.1%) in group C. Kaplan–Meier
survival curves for the two groups were not significantly different (p = 0.3). Surgical or percutaneous conversions occurred significantly more often in group A (7/15, 47%) than surgical conversions
in group C (4/22, 18%) (p = 0.03). Patients undergoing catheter drainage required an average of 2.2 sinograms/tube changes and kept catheters in for
an average of 52 days. Aspirates turned culture-positive in 13 of 22 patients (59%) who had chronic catheterization. In group
A, 3 of the 7 patients converted to percutaneous or surgical drainage had infected fluid at the time of conversion (total
positive culture rate in group A 3/15 or 20%).
Conclusions There is no apparent clinical benefit for catheter drainage of sterile fluid collections arising in acute pancreatitis as
the length of hospital stay and mortality were similar between patients undergoing aspiration versus catheter drainage. However,
almost half of patients treated with simple aspiration will require surgical or percutaneous drainage at some point. Disadvantages
of chronic catheter drainage include a greater than 50% rate of bacterial colonization and the need for multiple sinograms
and tube changes over an average duration of about 2 months. 相似文献