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51.
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of age diagnosed with low-grade astrocytoma. Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy. Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008). Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the outcome.  相似文献   
52.
Ganciclovir (GCV) prophylaxis or pre-emptive therapy significantly reduce the rate of cytomegalovirus (CMV) disease and viremia, but increase the potential for emergence of ganciclovir-resistant CMV strains. The inhibitor concentration at 50% (IC(50)) of GCV from 156 CMV isolates from 59 renal or heart transplant recipients was calculated by means of a rapid phenotypic susceptibility assay. Twenty-seven strains were from 14 patients undergoing GCV therapy. The IC(50) was higher in patients under the prophylaxis regimen. One CMV strain, from a heart transplant recipient, became GCV-resistant after 1 month of therapy (IC(50)=13.7 micromol/l). These data, together with clinical and virological markers, suggested that a switch to foscarnet was necessary, and good evolution was observed. Thus, assay of CMV susceptibility to GCV could be helpful in clinical management.  相似文献   
53.
54.
Lung cancer is the most prevalent malignancy in western countries and most of the patients present at advanced stages, but single splenic metastasis is exceptional instead. We report on a case of a seventy-three-year old male presenting with non-hemoptoic productive cough, constitutional syndrome and pain in the left lower quadrant. Physical examination and complementary radiological and hystologycal procedures revealed the presence of an adenocarcinoma of the left lung with probable splenic metastasis. The patient underwent splenectomy, which confirmed the diagnose of splenic metastasis of lung adenocarcinoma and, secondly, lung resection was performed. Topics about lung cancer metastasis are discussed.  相似文献   
55.
Development of a "leak-proof," knitted Dacron vascular prosthesis   总被引:2,自引:0,他引:2  
We have developed a technique to render knitted Dacron prostheses totally impervious to blood leak by impregnating the cloth with collagen. These grafts were prepared by the manufacturer, sterilized, and have an indefinite shelf life. The objective of this study was to determine whether collagen impregnation has a deleterious effect on surface thrombogenicity and graft healing. The infrarenal aortas of 30 mongrel dogs were replaced with 6 cm X 6 mm Dacron grafts (15 collagen-impregnated and 15 control). The collagen-impregnated prostheses were visibly indistinguishable from the control. After blood flow was restored, no interstitial bleeding occurred in the collagen grafts, in contrast to the control grafts that initially leaked profusely. When they recovered, the dogs were divided into three groups: group I (five collagen, five control), group II (five collagen, four control), and group III (five collagen, three control). The grafts were harvested at 3, 6, and 9 months, respectively. Retroperitoneal healing response, capsular thickness and adherence, completeness of neointimal healing, surface fibrinolytic activator activity, and sections taken for light and scanning electron microscopy were studied and compared in a blinded fashion. In a separate set of experiments, experimental and control grafts were compared for in vivo surface thrombogenicity. The healing data were identical in the experimental and control prostheses in all parameters. Of particular interest was that initial capsule adherence was better and surface thrombogenicity less in the collagen-impregnated prosthesis. We conclude that collagen impregnation of a knitted Dacron prosthesis has no deleterious effect for the term of observation of this experiment.  相似文献   
56.
Histomorphometric study was made on a series of sections of undecalcified epiphyseal femoral specimens from rats with experimental fluorosis. The results revealed osteosclerosis in Group A (5 ppm) being more severe than that in Group B (25 ppm) With the increase of fluoride dose, the parameters fell down instead of increased in parallel. There is seemingly a threshold over which osteosclerosis in fluorosis becomes less severe. In contrast to Bely's conclusion the authors proposed that, fluoride toxi- city, besides decreasing the number of osteoblasts, may also activate the osteoblasts. The number of osteoblasts may be increased with relative lower dose of fluoride also. The net outcome is the in crement in bone volume. When toxic dose of fluoride is higher enough (higher than the proposed threshold), however, the number of osteoblasts and its activity are inhibited. So are the osteocytes. This interpretation may be the cytological basis for osteosclerosis in the experimental fluorosis.  相似文献   
57.
The purpose of this study was to evaluate the ability of helical computed tomography (CT) to detect arterial injuries in gunshot wounds to the neck. In a blinded retrospective review, 54 helical CT scans of the cervical spine were evaluated for bullet/bone fragments, subcutaneous air, bullet path, hematoma, spine fractures, and pharyngoesophageal compromise. The distance of fragments to a major vessel was calculated. CT findings that correlated significantly with major arterial injury included the presence of fragments (bullet/bone) close to a major vessel (2.5 mm) and spine fractures. Visualizing fragments <5 mm from a vessel or a transcervical bullet trajectory predicted 12 of 13 major arterial injuries. We conclude that CT clearly depicts anatomic damage. Specific findings, such as the location of fragments and bullet trajectory adjacent to a vessel and spine fractures, indicate a higher probability of vascular damage, thus directing more definitive evaluation.  相似文献   
58.
Moderate increases in ``classical' biochemical markers of bone turnover have been described only in some patients with Camurati–Engelmann disease. However, the determination of the following ``new' markers has not been previously performed: serum osteocalcin (BGP), bone alkaline phosphatase (BAP), carboxyterminal propeptide of type I procollagen (PICP), aminoterminal propeptide of type I procollagen (PINP), tartrate-resistant acid phosphatase (TRAP), telopeptide carboxyterminal of type I collagen (ICTP), urinary pyridinoline (PYR), crosslinked N-telopeptides of type I collagen (NTX), and Crosslaps (CL). Such a determination may improve the evaluation of the disease activity. To evaluate the usefulness of biochemical markers of bone turnover reflecting Camurati–Engelmann disease activity we measured the levels of all these markers in four affected patients. The results were compared with bone scintigraphic indices of disease activity. Except for PICP and TRAP, bone formation and resorption markers were abnormal in all patients and were related to bone scan indices of disease activity. Among the markers of bone formation PINP, BAP, and BGP showed the highest values, whereas NTX and CL were the most sensitive markers of bone resorption. These results suggest that the determination of NTX or CL, and PINP or either BAP and BGP, associated with bone scan evaluation, provides the best assessment of Camurati–Engelmann disease activity. Received: 14 June 1996 / Accepted: 31 December 1996  相似文献   
59.
Pleural effusion in patients infected with the human immunodeficiency virus   总被引:1,自引:0,他引:1  
In order to analyze the etiology, cytological and biochemical characteristics, and outcome of pleural disease in patients infected with HIV, the medical records of 86 HIV-positive patients with pleural effusion were reviewed. Controls were 106 HIV-negative patients with parapneumonic or tuberculous effusion. Most HIV-positive patients were intravenous drug abusers (95.3%). Pleural effusions in HIV-positive patients were caused by infections in 76 (89.4%) cases. Parapneumonic effusion was diagnosed in 59 patients and tuberculous pleuritis in 15 patients.Staphylococcus aureus was the most frequently isolated bacteria. Parameters for differentiating complicated cases of parapneumonic exudate from uncomplicated cases, such as pleural fluid pH<7.20 (sensitivity 80% vs. 84.3%), pleural fluid glucose<35 mg/dl (sensitivity 45% vs. 56.25%) pleural fluid LDH > 1600 Ul/l (sensitivity 85% vs. 62.50%), showed similar sensitivity in HIV-positive and HIV-negative patients. Monocytes in pleural fluid were significantly decreased in tuberculous pleuritis in HIV-positive patients (506±425 vs. 1014±1196 monocytes/ml, p<0.05). No significant differences were detected in the outcome of HIV-positive and HIV-negative patients with pleural disease. It can be concluded that the pleural effusion was of predominantly infectious etiology in HIV-positive patients from populations with a high prevalence of intravenous drug abuse. Neither the biochemical parameters in pleural fluid nor the outcome differed significantly between HIV-positive and HIV-negative patients.  相似文献   
60.
AIMS: To estimate the prevalence of diabetes mellitus with three diagnostic criteria (WHO-1985 and 1999 and ADA-1997), evaluate their concordance and analyse the sensitivity and specificity of the different screening strategies for diabetes. METHODS: A cross-sectional population study with two-step sampling. One thousand and 34 people were selected randomly. A 75-g oral glucose tolerance test (OGTT) was performed and venous blood samples were obtained fasting and at 2 h. RESULTS: The prevalence of known Type 2 diabetes mellitus (DM-2) is 4%[95% confidence interval (CI) 2.8, 5.1]. By WHO-1985 criteria the prevalence of unknown DM-2 is 5.9% (4.5, 7.4); by ADA-1997 criteria 3.5% (2.5, 4.6) and by WHO-1999 criteria 7.3% (5.8, 8.8). Diagnostic overlap and statistical concordance (coefficient K) are WHO-1985/ADA-1997 29.3%, K=0.42; WHO-1985/WHO-1999 80%, K=0.88; ADA-1997/WHO-1999 48%, K=0.63. If only fasting glucose was used (following ADA-1997), 36.3% of those with diabetes (2-h glucose > or =11.1 mmol/l) would be diagnosed. If OGTT was performed (i) in those with a fasting glucose between 6.1 mmol/l and 6.9 mmol/l (9.8% of the population) we would diagnose 66.6%, and (ii) in all those between 5.7 mmol/l and 6.9 mmol/l (18.9% of the population) 81.8% would be diagnosed. CONCLUSIONS: The ADA criteria decrease the prevalence of DM in the adult population of Asturias by 2.4% and concordance with the classical criteria (WHO-1985) was only 29.3%. Using fasting glucose only (ADA-1997) diagnoses 36.3% of those with diabetes. The recent recommendations of the WHO-1999 increases this to 66.6%. To improve the diagnostic strategy for diabetes and detect up to 81.8% of patients, we propose the use of OGTT for all those with a fasting glucose between 5.7 mmol/l and 6.9 mmol/l.  相似文献   
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