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51.
Vasculitis is diagnosed with increasing frequency in the elderly. We hereby present the case of an 84-year-old male, who had weight loss, low-degree fever, anemia and epigastric pain. After 14 days of study with the tentative diagnosis of digestive neoplasia, a progressive renal insufficiency was detected. This clinical picture was secondary to ANCA-positive vasculitis. The case poses the differential diagnosis of non-oliguric acute renal failure (FRA) in elder people and the systematics of the study of renal insufficiency in individuals with previously unknown renal function. Also, this patient's history emphasizes the importance of acute deterioration of renal function as a guiding symptom for orienting the interpretation of clinical data. In the present case, a diagnostic hypothesis based only in the pursue of an occult digestive tumor misguided the attention from the main cause of the disease.  相似文献   
52.
alpha-Hemoglobin stabilizing protein (AHSP) is an abundant, erythroid-specific protein that forms a stable complex with free alpha-hemoglobin but not with beta-hemoglobin or hemoglobin A. As such, AHSP is required for normal erythropoiesis, probably acting by blocking the deleterious effects of free alpha-hemoglobin precipitation. In order to study the levels of expression of the AHSP gene during the different phases of erythropoiesis, we carried out a two-phase liquid culture of erythroid cells and real-time quantitative polymerase chain reaction. Blood from control volunteers was cultured with erythropoietin to stimulate differentiation. The different stages of erythropoiesis were confirmed by morphologic and flow cytometric analysis. The results showed a progressive increase in AHSP gene expression following the expression of alpha-globin gene, during maturation of the red blood cell precursors, confirming the probable important function of this protein during normal erythropoiesis.  相似文献   
53.
BACKGROUND: Assessment of clinical and pathologic features of large cell neuroendocrine carcinoma to confirm its specificity in the setting of high grade neuroendocrine pulmonary tumors. METHODS: From 1989 to 2001, 123 patients with a neuroendocrine carcinoma were surgically treated in a curative intent at a single institution. According to the 1999 World Health Organization classification, 20 patients were reviewed as having a large cell neuroendocrine carcinoma. Clinical data as well as detailed pathologic analysis and survival were collected. RESULTS: There were 18 men and 2 women. The median age was 62 years. Four patients had a preoperative diagnosis of large cell neuroendocrine carcinoma. The resections consisted of 14 lobectomies and 6 pneumonectomies. There was no operative death. Complications occurred in 7 patients (35%). Four patients had a stage I of the disease, 4 had stage II, 9 had stage III, and 3 had stage IV. At follow-up (median, 46 months), 13 patients died from general recurrence and 7 patients were still alive. Median time to progression was 9 months (range, 1 to 54 months). The 5-year survival rate was 36% (median, 49 months) and it seemed to be negatively influenced by the disease stage (54% for stage I-II vs 25% for stage III-IV; p = 0.07), the presence of metastatic lymph node (45% for N0/N1 vs 17% for N2; p = 0.12), or vessel invasion (66 vs 25%; p = 0.18). CONCLUSIONS: Large cell neuroendocrine carcinoma predominantly occurred in men. An accurate tissue diagnosis was rarely obtained preoperatively. Although overall survival after resection was substantial, large cell neuroendocrine carcinoma frequently showed pathologic features of occult metastatic disease, such as lymph node or vessel invasion, or both.  相似文献   
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55.
We present the case of a 32-year-old female patient referred to the Instituto Nacional de Cancerología (INCan) with a history of several months of systemic hypertension and epigastric pain associated to early postprandial satiety, fatigue, and dyspnea. At physical examination, a smooth, non-tender, palpable mass was found in right upper quadrant 7 cm below costal margin. Computed tomography (CT) scan showed right-sided non-parasitic liver cyst. The patient was taken to the operating room, where she presented hypertensive crisis of 180/125 mm Hg, which did not respond to midazolam therapy. The procedure was suspended and deferred. After blood pressure control with angiotensin II-antagonist and calcium-antagonist, the patient was submitted to laparotomy, where a wide deroofing of the lesion was performed. The postoperative evolution was uneventful and the patient has remained normotense without anti-hypertensive medication after 6 months of follow-up.  相似文献   
56.
Impetigo: an update   总被引:4,自引:0,他引:4  
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57.
The complete nucleotide sequence of the genome of Sinorhizobium meliloti, the symbiont of alfalfa, was reported in 2001 by an international consortium of laboratories. The genome comprises a chromosome of 3.65 megabases (Mb) and two megaplasmids, pSymA and pSymB, of 1.35 Mb and 1.68 Mb, respectively. Based on the nucleotide sequence of the whole genome, we designed a pathway of consecutive rearrangements leading to novel genomic architectures. In a first step we obtained derivative strains containing two replicons; in a second step we obtained a strain containing the genetic information in one single replicon of 6.68 MB. From this last architecture we isolated revertants containing two replicons, and from these we could return to the original architecture showing the three replicons. We found that the relative frequency of excision of cointegrated replicons is higher at the site used for the cointegration than at other sites. This might conciliate two apparently opposed facts: the highly dynamic state of genomic architecture in S. meliloti and the common observation that different isolates and derived cellular clones of S. meliloti usually present the architecture of one chromosome and two distinct megaplasmids. Different aspects that must be considered to obtain full advantage of the strategy of natural genomic design are discussed.  相似文献   
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59.
Failure of eruption of permanent molars is an uncommon condition with a range of possible causative factors. This retrospective study of 35 pediatric subjects assesses the influence of these factors in the prognosis. The study aims to broaden our understanding of an abnormality, which has a considerable clinical impact, and proposes a treatment protocol for the management of these patients.  相似文献   
60.
We report a clinical case of a 26 years old female who had a 2 years evolution chin tumour with hypercalcemia (11.8 mg/dl) and PTH (paratohormone) of 761 pg/ml. She underwent a CT scan and MRI of the mandible, as well as a biopsy followed by excision of the tumour by the maxilofacial surgeons. Our ENT Department asked for a Scintigraphy (Tc99s-mibi) and thoracic-cervical CT, which showed a lesion that turned out to be an adenoma of the lower right parathyroid gland after surgery and pathological examination. The patient suffered a Primary hyperparathyroidism that was the main stimulus for the Brown Tumour made up by macrophagos and multinuclear giant cells, being this the first manifestation of the metabolic disorder. This form of hyperparathyroidism is very rare in the clinic. We do a literature review to establish the differential diagnosis for such pathology.  相似文献   
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