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991.
The presence of tumor-initiating cells (CD44(+)/CD24(-)) in solid tumors has been reported as a possible cause of cancer metastasis and treatment failure. Nevertheless, little is know about the presence of CD44(+)/CD24(-) cells within the primary tumor and metastasis. The proportion of CD44(+)/CD24(-) cells was analyzed in 40 samples and in 10 lymph node metastases using flow cytometry phenotyping. Anti-human CD326 (EpCam; FITC), anti-human CD227 (MUC-1; FITC), anti-human CD44 (APC), and anti-human CD24 (PE), anti-ABCG2 (PE), and anti-CXCR4 (PeCy7) were used for phenotype analysis. The mean patient age was 60.5 years (range, 33-87 years); mean primary tumor size (pT) was 1.8 cm (0.5-3.5 cm). The Wilcoxon or Kruskal-Wallis test was used for univariate analyses. Logistic regression was used for multivariate analysis. The median percentage of CD44(+)/CD24(-) cells within primary invasive ductal carcinomas (IDC) was 2.7% (range, 0.2-71.2). In lymph node metastases, we observed a mean of 6.1% (range, 0.07-53.7). The percentage of CD44(+)/CD24(-) cells in IDCs was not associated with age, pT, tumor grade and HER2. We observed a significantly enrichment of CD44(+)/CD24(-) and ABCG2(+) cells in ESA(+) cell population in patients with positive lymph nodes (P = 0.02 and P = 0.04, respectively). Our data suggest that metastatic dissemination is associated with an increase in tumor-initiating cells in stage I and II breast cancer.  相似文献   
992.
Giant left atria (GLA) is a condition where the left atrial diameter exceeds 65 mm.1 It is closely related to rheumatic mitral valve regurgitation or mixed mitral disease with predominant regurgitation and tends not to occur in patients with mitral regurgitation due to other causes.2 The majority of patients are symptomatic with the most common symptoms being that of shortness of breath, dysphagia, palpitations, chest pain, and thromboembolic events.3 Massive asymptomatic enlargement of the left atrium is a rare entity. We present such a case. Copyright © 2010 Wiley Periodicals, Inc.  相似文献   
993.
There are many questions regarding the advantages and disadvatanges of a videolaparoscopic approach in the treatment of acute appendicits. The authors present the results of a non-randomized, prospective study with 496 patients admitted between January 1992 and March 1998 by the General Surgery Service of São Rafael Hospital -Salvador - BA - Brazil. The patients were submitted for appendicectomy by video laparoscopy or by the traditional open method, and variables such as surgery duration, morbidity, mortality, costs, and length of stay (LOS) were compared. The results demonstrate that laparoscopic appendicectomy is a safe alternative for treatment of acute appendicitis; however, there are several disadvantages that gradually must be overcome.  相似文献   
994.
The authors report a case of an asymptomatic 30-year-old female patient with an extensive cystic lesion continuous with the splenic parenchyma. A review of the literature and use of a videolaparoscopic approach to the treatment of these lesions is presented.  相似文献   
995.
996.
Osteopetrosis is a rare hereditary bone disorder presenting with variable clinical features and is characterized by an increase in bone density. The main clinical findings of the benign-type of osteopetrosis (autosomal dominant) are fractures and osteomyelitis of the mandible, leading to the detection of the disease. We report a case of autosomal dominant osteopetrosis with secondary mandibular osteomyelitis. Clinical and radiological patterns and treatment evaluation were assessed. The patient was referred for evaluation and treatment of an acute abscess in the left side of the face and osteomyelitis of the mandible. Several imaging studies were performed to assess the lesion and the adjacent bone and soft tissue structures. Treatment consisted of intravenous antibiotic therapy, debridement of the necrotic bone and sequestrum, and extra-oral drainage of the abscess, with submandibular access. Healing was uneventful.  相似文献   
997.
998.
Many excitable cells express L-type Ca(2+) channels (LTCCs), which participate in physiological and pathophysiological processes ranging from memory, secretion, and contraction to epilepsy, heart failure, and hypertension. Clusters of LTCCs can operate in a PKCalpha-dependent, high open probability mode that generates sites of sustained Ca(2+) influx called "persistent Ca(2+) sparklets." Although increased LTCC activity is necessary for the development of vascular dysfunction during hypertension, the mechanisms leading to increased LTCC function are unclear. Here, we tested the hypothesis that increased PKCalpha and persistent Ca(2+) sparklet activity contributes to arterial dysfunction during hypertension. We found that PKCalpha and persistent Ca(2+) sparklet activity is indeed increased in arterial myocytes during hypertension. Furthermore, in human arterial myocytes, PKCalpha-dependent persistent Ca(2+) sparklets activated the prohypertensive calcineurin/NFATc3 signaling cascade. These events culminated in three hallmark signs of hypertension-associated vascular dysfunction: increased Ca(2+) entry, elevated arterial [Ca(2+)](i), and enhanced myogenic tone. Consistent with these observations, we show that PKCalpha ablation is protective against the development of angiotensin II-induced hypertension. These data support a model in which persistent Ca(2+) sparklets, PKCalpha, and calcineurin form a subcellular signaling triad controlling NFATc3-dependent gene expression, arterial function, and blood pressure. Because of the ubiquity of these proteins, this model may represent a general signaling pathway controlling gene expression and cellular function.  相似文献   
999.
A case of tracheal agenesis diagnosed at birth is discussed in which surgical correction was attempted. Both main bronchi were divided and anastomosis of the main right bronchus to the larynx was attempted, after intrapericardial release of the right lung and severing of the lower pulmonary ligament: bronchoplastic reconstruction of the trachea was impossible. We think that tracheal agenesis, a rare cause of respiratory distress in the newborn, has no suitable therapy today. It is justified to attempt surgical correction if any promising device is at hand or if any doubt exists that an uncorrectable situation is present.  相似文献   
1000.
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