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101.
PURPOSE: To evaluate the incidence of bronchial carcinoid tumor (BCT) in population affected by various lung tumors, retrospectively reviewed between 1986-2001, and to emphasize the radiographic patterns if they are characteristic. MATERIALS AND METHODS: In the above mentioned period, chest x-ray and CT were performed in 1110 patients, both male and female, affected by lung neoplasms. RESULTS: 20 patients were affected by BCT (16 males, and 13 females), aged between 26 and 75 years (mean age 57.5), with histopathologic diagnosis of typical (9 cases, 31%) and atypical (20 cases, 69%) bronchial carcinoid tumors. Localized right lung lesion were as follows: 7 cases in superior, 9 in middle and 4 in inferior lobes; in the left lung, 5 cases in superior, and 4 in inferior lobes. Size of the lesions was as average 2.4 cm in diameter (with a range of 0.5-12 cm). On x-ray and CT images, BCT appeared as a well marginated nodule, of which 9 were peripheral and 20 central. DISCUSSION AND CONCLUSION: BCT are classified as neuroendocrine carcinomas,and are divided in typical and atypical forms, with variable grade of malignancy. Central neoplasms are symptomatic due to bronchial obstruction (i.e., pneumonia, atelectasis, bronchiectasis, emphysema and/or lung abscess); if airway obstruction is partial, then cough, wheezing and recurrent pulmonary infections occur. Peripheral tumors are generally asymptomatic and they are discovered occasionally, when chest x-ray is made for other reasons. Radiographic features are similar in typical and atypical BCT. In central tumors a rounded well circumscribed hilar mass is noted, with lobulated or bumpy margins. Central cavitation is not referred to. Peripheral BCT appear as a solitary nodule, inferioer then 3 cm in size, marginated, surrounded by normal pulmonary tissue. Signs and symptoms of BCT are evasive and vague. No current clinical or laboratory procedures are useful in confirming the diagnosis; particularly, no imaging modalities are able to differentiate between BCT and other pulmonary tumors. For this reason, a clinical radiologic endoscopic and histopathologic approach is necessary. CT is more sensiticve then conventional radiography, especially in detecting small lesions, calcification and enlarged lymph nodes. MRI may be useful in those patients, who cannot tolerate IV contrast media. Scintigraphy may be employed in discovering relapses and long standing metastases.  相似文献   
102.
The aim of this report was to evaluate the effectiveness of the endoscopic treatment of colonic polyps to allow secondary prophylaxis in order to prevent the onset of cancer arising from adenomas. From October 2002 to January 2004 we performed 487 colonoscopies on a patient group with the following indications: screening prior to kidney transplant; screening for colorectal cancer (patients positive at faecal occult blood testing); follow-up of patients who had undergone colonic resections for colorectal cancer; patients with other diseases. Colorectal polyps were diagnosed in 15 males and 15 females, with a mean age of 63 years. All the neoplasms were resected during colonoscopy and specimens sent for histological study. The histological examinations yielded the following results: 4 hyperplastic polyps; 9 tubular adenomas (6 with mild, 2 with mild-to-moderate, and 1 with severe dysplasia); 8 tubulo-villous adenomas (3 with mild, 1 with mild-to-moderate, and 4 with moderate dysplasia); 4 villous adenomas (3 with mild and 1 with severe dysplasia); 1 adenocarcinoma; 1 inflammatory polyp; in 3 cases we were unable to retrieve the polyps after polypectomy. Colonoscopic detection of a neoplasm allows us to remove it and send to the pathology laboratory for definitive histological diagnosis. Moreover, snare polypectomy can be a radical treatment for dysplastic polyps without stromal axis and basal membrane infiltration. We therefore conclude that colonoscopy allows not only early diagnosis of colonic neoplasms, but also radical curative treatment in the early stages.  相似文献   
103.
With the aim of assessing whether fenoldopam can help to preserve renal function after liver transplantation, we randomized 140 consecutive recipients with comparable preoperative renal function to receive fenoldopam 0.1 microg/kg/minute (group F, 46 patients), dopamine 3 microg/kg/minute (group D, 48 patients), or placebo (group P, 46 patients) from the time of anesthesia induction to 96 hours postoperatively. There were no differences between the groups in intraoperative urinary output or furosemide administration (both P =.1). Daily recordings made during the first 4 postoperative days revealed no significant differences in urinary output (P =.1), serum creatinine (P =.5), the incidence of renal insufficiency (P =.7), the need for loop diuretics (P =.9) or vasoactive drugs (P =.8). In comparison with preoperative levels, creatinine clearance at the end of the study in the patients receiving fenoldopam remained substantially unchanged, whereas it decreased by 39 and 12.3%, respectively, in the subjects receiving placebo or dopamine (P <.001); blood cyclosporine A (CsA) levels were similar in the 3 groups (P =.1). Three subjects died in the intensive care unit (1 in each group, P =.9), 2 of them had renal failure. In conclusion, our results confirm the inefficacy of dopamine in preventing or limiting early renal dysfunction after liver transplantation, and suggest that fenoldopam may preserve creatinine clearance by counterbalancing the renal vasoconstrictive effect of CsA, as it has been reported in previous experimental studies.  相似文献   
104.
We previously reported the characterization of human osteoclast-associated receptor (hOSCAR), a novel Fc receptor gamma-chain (FcRgamma)-associated receptor expressed by myeloid cells. Here we show that ligation of hOSCAR by specific antibodies promotes dendritic cell (DC) survival by an extracellular signal-regulated kinase (ERK)- and phosphatidylinositol 3-kinase (PI3K)-dependent pathway, linked to expression of the Bcl-2 and Bcl-x(L) antiapoptotic molecules. Crosslinking of hOSCAR leads to maturation of DCs, as demonstrated by up-regulation of maturation markers, decrease in dextran uptake capacity, and secretion of immunesystem effectors such as interleukin-8 (IL-8)/CXC chemokine ligand 8 (CXCL8), IL-12 p40, monocyte chemoattractant protein-1 (MCP-1)/chemokine receptor ligand 2 (CCL2) and macrophage-derived chemokine (MDC)/CCL22. Stimulation of hOSCAR acts in conjunction with the Toll-like receptor (TLR) ligands, lipopolysaccharide (LPS), R-848, and polyinosinic-polycytidylic acid (poly(I:C)), to increase the expression of maturation markers, and to modulate cytokine release. A PI3K-dependent up-regulation of IL-10 release is observed with all the TLR ligands used, whereas regulation of IL-12 production is variable depending on the TLR stimulated. hOSCAR engagement on DCs did not significantly increase the proliferation of naive T cells; however, when co-incubated with TLR ligands, an enhanced proliferation was observed. The percentage of interferon (IFN)-gamma-producing T cells is decreased when hOSCAR engagement is combined with LPS stimulation. Altogether, these data suggest that hOSCAR may modulate the responses of both innate resistance and adaptive immunity.  相似文献   
105.
We evaluated the effects of daily prednisone therapy on alveolitis parameters and pulmonary function tests over a six month period in patients with active pulmonary sarcoidosis (>28% T lymphocytes in bronchoalveolar lavage and positive gallium-67 (67Ga) lung scans). 10 patients with biopsyproven lung disease were studied. Analysis of bronchoalveolar lavage cells and of67Ga scanning at the beginning and at the end of the study period demonstrated that prednisone treatment significantly lowered the percentages of T lymphocytes in bronchoalveolar lavage in all patients (baseline 48±3%, after treatment 19±5%, p<0.01) while67Ga lung scans improved in 8 of the 10 patients. Pulmonary function tests showed improvement of the parameters studied (+7.5±2.1% mean change in vital capacity, +4.7±1.6% mean change in total lung capacity, +5.4±2% mean change in forced expiratory volume in one second and +6.2±1.5% mean change in diffusing capacity). In addition none of the treated patients deteriorated functionally and 9 of the 10 patients improved more than 10% in at least one parameter. These results indicate that daily oral prednisone therapy is effective in suppressing the alveolitis in pulmonary sarcoidosis and that it is able to preserve lung functions in patients who, without treatment, would be likely to deteriorate. Supported by C.N.R. grants no 82.00200.04 and 82.02057.56  相似文献   
106.
107.
This article is a retrospective study comparing the efficacy of Regnauld arthroplasty to first ray osteotomies for the treatment of hallux valgus. One hundred consecutive cases of Regnauld arthroplasties were compared with 100 consecutive first ray osteotomies. One hundred fourty-one patients were available for follow-up, and based on clinical/radiographic examinations, 72 were treated with the osteotomy protocol (group A) and 69 with Regnauld arthroplasty (group B). Age at surgery, clinical symptoms, and preoperative radiologic findings were similar for the 2 groups; there was a preponderance of female patients (90%). The average follow-up was 49 months in group A and 51 months in group B. Clinical evaluation showed in the osteotomy group a more stable correction (79% v 49%), greater pain reduction (measured in a visual analog scale from 0 = pain free to 10 = deep intolerable pain), increased residual articular excursion of the first metatarsophalangeal joint (27 degrees of active dorsiflexion from neutral position v 8 degrees ), and less presence of central metatarsalgia (15% v 34%) (P <.05). The radiographic evaluation expressed more stable correction values in group A for the following parameters: joint preservation, sesamoid position, intermetatarsal angle (7 degrees v 12 degrees ), abduction angle of the hallux (14 degrees v 20 degrees ), and proximal articular set angle (8 degrees v 18 degrees ) (P <.05).  相似文献   
108.
Bello L  Lucini V  Giussani C  Carrabba G  Pluderi M  Scaglione F  Tomei G  Villani R  Black PM  Bikfalvi A  Carroll RS 《Neurosurgery》2003,52(1):177-85; discussion 185-6
OBJECTIVE: The biological features of malignant gliomas include high cell proliferation, extensive local infiltration of tumor cells into normal brain, and marked neovascularization. alphavbeta3 integrin is highly expressed in malignant gliomas and plays a role in glioma growth. This article investigates the in vitro and in vivo effects of a synthetic alphavbeta3 integrin inhibitor called IS20I on human malignant gliomas. METHODS: The in vitro effects of IS20I were studied by performing adhesion assays, competition studies, semi-in vivo angiogenic assays, and migration and proliferation assays. For the in vivo experiments, IS20I was administered systemically in nude mouse intracranial and subcutaneous malignant glioma models. RESULTS: IS20I reacted selectively to alphavbeta3 integrin in glioma cells and tissues. In vitro, IS20I strongly inhibited angiogenesis and simultaneously exhibited potent antimitotic and antimigratory effects on numerous tumor and endothelial cell lines. In addition, at high concentrations, IS20I induced endothelial and tumor cell apoptosis. In vivo, when IS20I was administered intraperitoneally in subcutaneous and intracranial nude mouse glioma models, it potently reduced malignant glioma growth. Inhibition levels of 76 and 82% were observed at concentrations of 1 and 5 mg/kg, respectively, in the U87 intracranial model. The suppression of tumor growth is associated with a decrease in tumor vascularity, an increase in apoptosis, and a decrease in tumor cell proliferation. CONCLUSION: This work expands the understanding of the effects of anti-alphavbeta3 integrin inhibitors on malignant gliomas. In addition to direct proapoptotic and antiangiogenic effects, IS20I inhibits tumor and endothelial cell proliferation and migration, resulting in a potent inhibition of glioma growth in vivo.  相似文献   
109.
110.
Well-differentiated thyroid neoplasms may be included among the most frequently occurring thyroid carcinomas. Papillary ca. is without doubt the best behaved type. The aim of the present work is to perform a retrospective case history study to assess patients with con papillary ca. who have been treated surgically over the last 17 years and have been subjected to periodic checks. A sample of patients was therefore extrapolated who had all undergone total thyroidectomy for papillary ca. of the thyroid. The incidence of local recurrence of the disease was verified, together with the results at distance. Furthermore, the assessments performed were evaluated and compared. From the sample of patients observed we inferred that papillary carcinoma of the thyroid can have a good prognosis over time provided periodic random checks are carried out.  相似文献   
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