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71.
The patency of a polytetrafluoroethylene (Gortex®) graft 9½ years after coronary artery bypass graft surgery (CABG) is demonstrated. While this material is not commonly used as a conduit because of limited success in the past, this case demonstrates that, given the right circumstances, longterm patency is possible. Since available conduits for CABG are quite often limited, viable alternatives may be lifesaving and require further evaluation. In addition to mechanical considerations such as size, length, and material, anticoagulation and strict management of hyperlipidemia may be critical. 相似文献
72.
Chade AR Rodriguez-Porcel M Rippentrop SJ Lerman A Lerman LO 《American journal of hypertension》2003,16(2):111-115
BACKGROUND: Hypercholesterolemia (HC) is a risk factor for renal disease that may activate the angiotensin II type 1 (AT1) receptor and accelerate renal damage. Early diet-induced HC impairs renal perfusion responses, but it is yet unknown whether the AT1 receptor is involved. This study tested the hypothesis that AT1 receptor blockade improved renal perfusion and functional responses in hypercholesterolemic pigs. METHODS: Regional renal hemodynamics and function in vivo were quantified bilaterally in pigs, at baseline and during vasoactive challenge (acetylcholine or sodium nitroprusside), using electron beam computed tomography after 12 weeks of normal (n = 6) or HC diet (n = 6), or HC diet supplemented (100 mg/d) with the AT1-receptor antagonist irbesartan (HC + AT1, n = 6). RESULTS: Basal cortical and medullary perfusion was similar among the groups. Basal tubular function was similar on normal and HC diets, whereas HC + AT1 showed decreased proximal and distal fluid reabsorption. Hypercholesterolemic pigs had blunted cortical perfusion (P = .22) and augmented tubular responses to acetylcholine, whereas on HC + AT1 diet, cortical perfusion (P = .002) and tubular function were similar to normal animals. This was associated with decreased systemic levels of the oxidative stress markers thiobarbituric acid reactive substances. CONCLUSIONS: The AT1 receptor blockade in HC improves renal perfusion and tubular functional responses to endothelium-dependent vasodilators, in association with a decrease in oxidative stress. These results imply involvement of the renin-angiotensin system in the blunted renal cortical perfusion responses observed in HC, and suggest a potential role for these agents in preservation of intrarenal hemodynamics and function in HC. 相似文献
73.
Abstract: Thoracic splenosis (TS) is autoimplantation of ectopic splenic tissue in the thoracic cavity that occurs following splenic injury. The majority of cases of TS are asymptomatic and are diagnosed in the course of an evaluation of incidentally discovered pulmonary lesions. Some cases may be difficult to diagnose, especially if features suggesting TS are not recognized. This may lead to an extensive work-up and unnecessary invasive diagnostic procedures including thoracotomy. This case report describes a 40-year-old man, who was diagnosed incidentally with TS, several years after the initial injury. Multiple, asymptomatic, left-sided pleural based lesions associated with a history of thoracoabdominal injury and splenectomy are the key points that should alert suspicion of TS, which can then simply be confirmed by a Tc-99m sulphur colloid radionuclide scan. Most patients are treated conservatively unless they are symptomatic. Physicians must recognize the key features suggesting a diagnosis of TS, order appropriate imaging studies and avoid unnecessary invasive diagnostic procedures. 相似文献
74.
BACKGROUND: Risk stratification in Brugada syndrome is controversial, especially in asymptomatic individuals. OBJECTIVE: The purpose of this study was to evaluate tissue Doppler echocardiography in risk stratification of Brugada syndrome. METHODS: Patients with Brugada ECG pattern were enrolled in the study. Left ventricular (LV) preejection period was defined as the time interval between onset of the QRS complex and onset of LV lateral wall systolic wave. Right ventricular (RV) preejection period was defined as the time interval between onset of the QRS complex and onset of RV lateral wall systolic wave. Delay in onset of contraction between RV and LV was defined as RV preejection time - LV preejection time [PET((RV-LV))]. RESULTS: Type 1, 2, and 3 Brugada ECG pattern was found in 30, 56, and 31 patients, respectively. PET((RV-LV)) was significantly greater in type 1 Brugada patients (39.2 +/- 3.2 ms) compared with type 2 (5 +/- 0.3 ms) and 3 (5 +/- 0.4 ms) Brugada patients as well as controls (4.6 +/- 0.3 ms, P <.01 for all comparisons). Among type 1 Brugada patients, PET((RV-LV)) was significantly greater in patients who had previous cardiac events compared with asymptomatic subjects (48.2 +/- 4.3 ms vs 29.5 +/- 3.6 ms, P <.05). In the presence of type 1 Brugada ECG pattern, PET((RV-LV)) > or =40 ms identifies patients likely to have cardiac events, with 85.7% sensitivity and 93.7% specificity. CONCLUSION: PET((RV-LV)) is an important risk indicator for Brugada syndrome. 相似文献
75.
Graft-versus-host disease (GVHD) is a severe disorder and despite therapeutic efforts to decrease its distressing clinical manifestations, treatment is still not optimal. Here we report the results of studies, in which the purine analogue, fludarabine phosphate, was used in an attempt to modify and decrease GVHD after stem cell transplantation, across major histocompatibility barriers for murine leukemia. B-cell leukemia (BCL-1) bearing (BALB/c x C57BL/6) F1 mice received two cycles of fludarabine (0.8 mg/kg) for 5 days every 2 weeks, followed by 400 mg/kg cyclophosphamide i.p. Animals were then transplanted with C57BL/6 precursor cells and the development of leukemia and extent of GVHD was monitored both clinically and histopathologically. In the fludarabine-treated group, only nine of 28 (32%) mice developed leukemia, compared to 25 of 33 (76%) of control animals (P=0.0006 ). Mice treated with fludarabine-containing regimens prior to transplantation also had much less GVHD both clinically and at autopsy, while graft-versus-leukemia appeared to be augmented in the same animals. 相似文献
76.
Maharshak N Arbel Y Gal-Oz A Rogowski O Shapira I Berliner S Vered Y Canaani J Dotan I 《Journal of digestive diseases》2008,9(3):140-143
OBJECTIVE: The recently introduced Bayer wide‐range C‐reactive protein (wr‐CRP) assay might be relevant for the real‐time low‐cost and online determination of inflammatory bowel disease (IBD) activity. Our aim was to examine whether wr‐CRP can substitute for the Dade Behring high sensitivity C‐reactive protein (hs‐CRP) assay in IBD patients. METHODS: A total of 71 patients with IBD, of whom 48 had Crohn's disease CD and 23 had ulcerative colitis (UC) with various intensities of disease activity participated in the study. The CRP of patients who were under treatment at the Department of Gastroenterology and Liver Diseases were measured using both wr‐CRP and the hs‐CRP. RESULTS: A significant (r = 0.995; P < 0.001) correlation was noted between the hs‐CRP and wr‐CRP measurements for the whole sample as well as for the two diseases, CD (r = 0.994; P < 0.001) and UC (r = 0.997; P < 0.001), which were analyzed separately. CONCLUSION: The Bayer wr‐CRP assay might be a useful low‐cost and real‐time inflammation‐sensitive biomarker in patients with IBD. 相似文献
77.
78.
Artur Hahn Julia Bode Allen Alexander Kianush Karimian-Jazi Katharina Schregel Daniel Schwarz Alexander C Sommerkamp Thomas Krüwel Amir Abdollahi Wolfgang Wick Michael Platten Martin Bendszus Bjrn Tews Felix T Kurz Michael O Breckwoldt 《Journal of cerebral blood flow and metabolism》2021,41(7):1536
Three-dimensional assessment of optically cleared, entire organs and organisms has recently become possible by tissue clearing and selective plane illumination microscopy (“ultramicroscopy”). Resulting datasets can be highly complex, encompass over a thousand images with millions of objects and data of several gigabytes per acquisition. This constitutes a major challenge for quantitative analysis. We have developed post-processing tools to quantify millions of microvessels and their distribution in three-dimensional datasets from ultramicroscopy and demonstrate the capabilities of our pipeline within entire mouse brains and embryos. Using our developed acquisition, segmentation, and analysis platform, we quantify physiological vascular networks in development and the healthy brain. We compare various geometric vessel parameters (e.g. vessel density, radius, tortuosity) in the embryonic spinal cord and brain as well as in different brain regions (basal ganglia, corpus callosum, cortex). White matter tract structures (corpus callosum, spinal cord) showed lower microvascular branch densities and longer vessel branch length compared to grey matter (cortex, basal ganglia). Furthermore, we assess tumor neoangiogenesis in a mouse glioma model to compare tumor core and tumor border. The developed methodology allows rapid quantification of three-dimensional datasets by semi-automated segmentation of fluorescently labeled objects with conventional computer hardware. Our approach can aid preclinical investigations and paves the way towards “quantitative ultramicroscopy”. 相似文献
79.
Pakpour Amir H. Griffiths Mark D. Lin Chung-Ying 《International journal of mental health and addiction》2021,19(6):2407-2410
International Journal of Mental Health and Addiction - 相似文献
80.