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111.
Bernardes A Dionísio J Diogo D Coelho P Patrício J 《Surgical and radiologic anatomy : SRA》2005,27(2):79-85
Intraoperative hemostatic suture to treat a bleeding duodenal ulcer is sometimes difficult when there is massive hemorrhage. The aims of this paper are: (1) to describe a practical and easy intraoperative procedure which quickly decreases a massively bleeding duodenal ulcer, allowing the surgeon to identify the bleeding site clearly and obtain definitive hemostasis by suturing the involved vessels with a low risk of common bile duct lesion; and (2) to study in cadavers the anatomical basis of this surgical procedure already successfully performed on patients. Fourteen patients with massive duodenal ulcer bleeding, after unsuccessful endoscopic hemostasis, were operated on and included in this study. After surgical anterior gastroduodenotomy, the surgeon introduced a finger in a downward and forward direction in the bursa omentalis vestibule through the omental foramen. This simple and quick procedure decreased hemorrhage by compressing the gastroduodenal artery against the first part of the posterior surface of the duodenum. Twenty-four fresh blocks of normal tissue were removed from cadavers and were injected with silicone rubber through the common hepatic artery. The distance between the gastroduodenal artery and the omental foramen was measured. With this maneuver the surgeon can clearly see the exact bleeding site and perform an adequate suture with a minor risk of common bile duct lesion. 相似文献
112.
Xavier AC Siqueira SA Costa LJ Mauad T Nascimento Saldiva PH 《Virchows Archiv : an international journal of pathology》2005,446(3):225-231
Autopsy findings of missed diagnoses that would probably have changed management or prognosis occur in up to 29% of cases in general hospitals. Such proportions may be higher in subsets of patients with complex diseases. We reviewed 2908 consecutive autopsies performed over a period of 29 months in a large-volume hospital, analyzing 118 autopsies of patients with hematological malignancies or severe aplastic anemia. A review of macroscopic reports as well as microscopic examination of tissue samples was performed. Medical records were reviewed for clinical diagnoses. Discordances between clinical and autopsy diagnoses were classified using Goldmans criteria. Additionally, we searched for clinical parameters correlated with occurrence of class-I discrepancy using a multivariate method. Median age was 46.5 years, and 25.4% had received a hematopoietic stem-cell transplant. Overall, 11.9% (6.6–19.1%) of patients died before conclusion of the hematological diagnosis and 33% (24.6–42.3%) died with no active hematological disease. We found class-I discrepancy in 31.3% (23.1–40.5 %) of cases. The most common among these diagnoses were hematological disease, pneumonia and gastrointestinal bleeding. In a univariate analysis, being elderly (P=0.04) was positively correlated with the finding of class-I discrepancies; while, having received previous specific hematological treatment (P=0.0005) or hematopoietic stem-cell transplants (P=0.013), or being admitted to a specialized hematology unit (P=0.0006) were negatively correlated to the occurrence of such discrepancies. Multivariate analysis showed that care in a specialized hematology unit (OR 0.34, 0.12–0.93) was independently associated with lower occurrence of discrepancies. We concluded that critical diagnoses are often missed in highly complex hematological patients especially in the absence of admission to specialized hematology units. 相似文献
113.
Rheumatic heart disease: proinflammatory cytokines play a role in the progression and maintenance of valvular lesions 总被引:3,自引:0,他引:3 下载免费PDF全文
Guilherme L Cury P Demarchi LM Coelho V Abel L Lopez AP Oshiro SE Aliotti S Cunha-Neto E Pomerantzeff PM Tanaka AC Kalil J 《The American journal of pathology》2004,165(5):1583-1591
Heart lesions of rheumatic heart disease (RHD) patients contain T-cell clones that recognize heart proteins and streptococcal M peptides. To functionally characterize heart-infiltrating T lymphocytes, we evaluated their cytokine profile, both directly in situ and in T-cell lines derived from the heart (HIL). Interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, interleukin (IL)-4, and IL-10 expressions were characterized in 20 heart tissue infiltrates from 14 RHD patients by immunohistochemistry. IFN-gamma-, TNF-alpha-, and IL-10-positive cells were consistently predominant, whereas IL-4 was scarce in the valves. In agreement with these data, the in vitro experiments, in which 13 HILs derived from heart samples of eight patients were stimulated with M5 protein and the immunodominant M5 (81-96) peptide, IL-4 was detected in HIL derived from the atrium (three of six) but not from the valve (zero of seven). IFN-gamma and IL-10 production were detected in culture supernatants in 11 of 13 and 6 of 12 HILs, respectively. The predominant IFN-gamma and TNF-alpha expression in the heart suggests that Th1-type cytokines could mediate RHD. Unlike in reversible myocardium inflammation, the significantly lower IL-4 expression in the valvular tissue (P = 0.02) may contribute to the progression of the RHD leading to permanent valvular damage (relative risk, 4.3; odds ratio, 15.8). The lack of IL-4 in vitro production by valve-derived HIL also emphasizes the more severe tissue destruction in valves observed in RHD. 相似文献
114.
Pleasant and unpleasant emotional stimuli are frequently conceptualized as motivators for action. This notion was examined using focal transcranial magnetic stimulation (TMS). Ten healthy participants viewed pleasant, neutral, and unpleasant pictures from the International Affective Picture System (IAPS). During picture viewing, focal TMS was applied to the right motor cortex over the area innervating the first dorsal interosseous muscle of the left hand. Corticomotor excitability was larger while viewing negative pictures than while viewing neutral or positive images, as evidenced by greater motor evoked potentials. No difference was found between pleasant and neutral pictures. These results are consistent with models of emotion in which the neural networks underlying negative emotions have selective, direct connections to brain structures that mediate motor responses. 相似文献
115.
A non-linear morphometric feature selection approach for breast tumor contour from ultrasonic images
Pereira WC Alvarenga AV Infantosi AF Macrini L Pedreira CE 《Computers in biology and medicine》2010,40(11-12):912-918
Ultrasound breast images have been used to improve diagnostics and decrease the number of unneeded biopsies. Malignant breast tumors tend to present irregular and blurred contours while benign ones are usually round, smooth and well-defined. Accordingly, investigating the tumor contour may help in establishing diagnosis. Herein, Mutual Information and Linear Discriminant Analysis were implemented to rank morphometric features in discriminating breast tumors in ultrasound images. Seven features were extracted from Convex Polygon and the Normalized Radial Length techniques. By applying a Mutual Information based approach, it was possible to identity features with possibly non-linear contributions to the outcome. 相似文献
116.
Tatiana Victoni Fernando Rodrigues Coelho Alexandre Learth Soares Andressa de Freitas Thomas Secher Rodrigo Guabiraba François Erard Ricardo Martins de Oliveira-Filho B. Boris Vargaftig Gregoire Lauvaux Mamdouh A. Kamal Bernhard Ryffel René Moser Wothan Tavares-de-Lima 《Medical microbiology and immunology》2010,199(1):35-42
Innate immune responses against microorganisms may be mediated by Toll-like receptors (TLRs). Intestinal ischemia–reperfusion (i-I/R) leads to the translocation of bacteria and/or bacterial products such as endotoxin, which activate TLRs leading to acute intestinal and lung injury and inflammation observed upon gut trauma. Here, we investigated the role of TLR activation by using mice deficient for the common TLR adaptor protein myeloid differentiation factor 88 (MyD88) on local and remote inflammation following intestinal ischemia. Balb/c and MyD88?/? mice were subjected to occlusion of the superior mesenteric artery (45 min) followed by intestinal reperfusion (4 h). Acute neutrophil recruitment into the intestinal wall and the lung was significantly diminished in MyD88?/? after i-I/R, which was confirmed microscopically. Diminished neutrophil recruitment was accompanied with reduced concentration of TNF-α and IL-1β level. Furthermore, diminished microvascular leak and bacteremia were associated with enhanced survival of MyD88?/? mice. However, neither TNF-α nor IL-1β neutralization prevented neutrophil recruitment into the lung but attenuated intestinal inflammation upon i-I/R. In conclusion, our data demonstrate that disruption of the TLR/MyD88 pathway in mice attenuates acute intestinal and lung injury, inflammation, and endothelial damage allowing enhanced survival. 相似文献
117.
Napoleão TH Pontual EV de Albuquerque Lima T de Lima Santos ND Sá RA Coelho LC do Amaral Ferraz Navarro DM Paiva PM 《Parasitology research》2012,110(2):609-616
Aedes aegypti transmits the viruses that cause yellow and dengue fevers. Vector control is essential, since a vaccine for dengue has not
as yet been made available. This work reports on the larvicidal activity of Myracrodruon urundeuva leaf lectin (MuLL) against A. aegypti fourth-stage larvae (L4). Also, the resistance of MuLL to digestion by L4 gut proteases and the effects of MuLL on protease, trypsin-like and α-amylase activities from L4 gut were evaluated to determine if lectin remains active in A. aegypti gut and if insect enzyme activities can be modulated by MuLL. MuLL promoted mortality of L4 with LC50 of 0.202 mg/ml. Haemagglutinating activity of MuLL was detected even after incubation for 96 h with L4 gut preparation containing protease activity. MuLL affected the activity of gut enzymes, inhibiting protease and trypsin
activities and stimulating α-amylase activity. The results suggest that MuLL may become a new biodegradable larvicidal agent
for dengue control. Larvicidal activity of MuLL may be linked to its resistance to proteolysis by larval enzymes and interference
in the activity of digestive larval enzymes. 相似文献
118.
This study investigates the effects of peer influence on the food intake of overweight and normal-weight children. A mixed factorial design was employed, with children's weight status (overweight vs. normal-weight) as a between-subjects factor, and social context (alone vs. group) as a within-subjects factor. A total of 32 children (n=17 overweight and n=15 normal-weight) between the ages of 6-10 years participated in this study. Findings from the random regression model indicated that overweight children ate more when with others than when alone, while in contrast normal-weight ate more with others than they did when alone. Therefore, social context differentially impacts the eating behavior of overweight and normal-weight children. This study underscores differences in responses to the social environment between overweight and non-overweight youths, and suggests that social involvement may be an important tool in treatment and prevention programs for overweight and obesity. 相似文献
119.
120.
Ibrahim Hashim A Cornnell HH Coelho Ribeiro Mde L Abrahams D Cunningham J Lloyd M Martinez GV Gatenby RA Gillies RJ 《Clinical & experimental metastasis》2011,28(8):841-849
The tumor microenvironment is acidic as a consequence of upregulated glycolysis and poor perfusion and this acidity, in turn,
promotes invasion and metastasis. We have recently demonstrated that chronic consumption of sodium bicarbonate increased tumor
pH and reduced spontaneous and experimental metastases. This occurred without affecting systemic pH, which was compensated.
Additionally, these prior data did not rule out the possibility that bicarbonate was working though effects on carbonic anhydrase,
and not as a buffer per se. Here, we present evidence that chronic ingestion of a non-volatile buffer, 2-imidazole-1-yl-3-ethoxycarbonylpropionic
acid (IEPA) with a pK
a of 6.9 also reduced metastasis in an experimental PC3M prostate cancer mouse model. Animals (n = 30) were injected with luciferase expressing PC3M prostate cancer cells either subcutaneously (s.c., n = 10) or intravenously (i.v., n = 20). Four days prior to inoculations, half of the animals for each experiment were provided drinking water containing 200 mM
IEPA buffer. Animals were imaged weekly to follow metastasis, and these data showed that animals treated with IEPA had significantly
fewer experimental lung metastasis compared to control groups (P < 0.04). Consistent with prior work, the pH of treated tumors was elevated compared to controls. IEPA is observable by in
vivo magnetic resonance spectroscopy and this was used to measure the presence of IEPA in the bladder, confirming that it
was orally available. The results of this study indicate that metastasis can be reduced by non-volatile buffers as well as
bicarbonate and thus the effect appears to be due to pH buffering per se. 相似文献