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61.
From acetone extracts of the exudate of the tree BURSERA ARIENSIS, a new bilignan, named ariensin, has been isolated and characterized as (2R,3R)-bis-2.3-(3.4-methylenedioxybenzyl-)-1.4-butanediol diacetate. The structure has been determined from UV, IR, (1)H-NMR and (13)C-NMR data of the natural product, the dibromo derivative and the hydrolysis product. The optical rotation of the latter allowed the determination of the absolute configuration.  相似文献   
62.
Presentation of one case of hyporreflexic bladder like a first step of neurotoxicity due to Vinca alkaloids. These drugs produces peripheral neuropathies as usual, but in some rare occasions they may affect to the autonomic nervous system with its effects in the bladder producing hyporreflexic. This disease reverts spontaneously after suppressing drugs.  相似文献   
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Contribution of a retrospective series of 16 patients with type II absorptive hypercalciuria over a total of 1.041 patients undergoing metabolic study due to relapsing renal lithiasis. Clinical history of lithiasis, biochemistry prior to treatment and instituted therapy were examined in all cases. Stones composition, radiologic appearance of lithiasis and evolution of biochemical parameters after medical treatment with a mixture of phosphates were also studied.  相似文献   
64.
The schwannoma is a tumor resulting from the Schwann cells of neural shwath, being its retroperitoneal localization quite unusual. This tumor is clinically unspecified and in most of the cases it originates symptoms coming from the compression of the close structures when its localization is retroperitoneal. Its diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. The treatment is surgical radical exeresis with subsequent followup. We report a new case of this uncommon retroperitoneal pathology in a female patient showing a nonspecific clinic. Two years after the surgery she remains asymptomatic without any radiological evidence of recidive.  相似文献   
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PURPOSE: Neurofibromatosis type 1 (NF1) is characterized by systemic development of neurofibromas. Early clinical diagnosis can be ambiguous, and genetic diagnosis can be prohibitively difficult. Dysregulation of a number of growth factors has been suggested to be a mechanism of pathogenesis. This study was performed to assess the contribution of circulating growth factors for diffuse tumorigenesis and the diagnostic value of circulating growth factor identification in serum. EXPERIMENTAL DESIGN: The growth stimulation of neurofibroma-derived cells by serum from NF1 patients was tested, and serum growth factor levels in a cohort of NF1 patients (n = 39) between the ages of 7 and 70 years were analyzed. RESULTS: Concentrations of midkine (MK) and stem cell factor, but not epidermal growth factor, were substantially increased in serum of NF1 patients when compared with healthy controls. Within the NF1 group, MK levels increased dramatically at puberty from an average of 0.79 ng/mL in patients <18 years to 1.18 ng/mL in patients >18 years old. Stem cell factor and MK concentrations above a defined threshold in serum of NF1 patients are of diagnostic benefit for 96% of patients in the cohort tested. Furthermore, serum from NF1 patients enhanced proliferation of human neurofibroma-derived primary Schwann cells and endothelial cells substantially better than normal serum. CONCLUSIONS: Enhanced circulating growth factor levels contribute to diffuse tumorigenesis in NF1 and may provide the basis for molecular diagnosis.  相似文献   
67.
Prostatic carcinoma may be diagnosed by the clinic manifestations or by the symptoms for locoregional disemination and distance metastasis. The lymphatic system is the first metastatic station, which is affected in a high percentage of cases. Event it may simulate lymphoproliferatives process and it si uncommon the lymphatic macroaffectation at first. In theses cases, the histologic and immunohistochemical study by the determination of prostatic specific antigen in lymph nodes can provice the diagnosis. Treatment of these tumors is palliative with hormonotherapy. Prognosis is bad with a low survival at five years.  相似文献   
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BACKGROUND: Some patients develop proteinuria and progressive renal failure after unilateral nephrectomy, although the majority of patients maintain normal renal function. Reasons to explain this different evolution are not known. METHODS: A cross-sectional study was performed in 73 patients who had undergone unilateral nephrectomy 13.6 +/- 8.6 years before. Patients with morphologic abnormalities in the remaining kidney, systemic disorders, or abnormal renal function at the time of nephrectomy were excluded. All of the 73 included patients showed normal renal function and negative proteinuria at nephrectomy. The patient's medical records were reviewed, and clinical and analytical data throughout follow-up were obtained. RESULTS: Fifty-three out of the 73 patients (group I) showed a normal renal function and negative proteinuria at the cross-sectional study. The remaining 20 patients (group II) showed proteinuria (3.4 +/- 3.1 g/day). The time elapsed between nephrectomy and proteinuria appearance was 10.1 +/- 6.1 years. Thirteen patients of group II had developed renal insufficiency (serum creatinine at the cross-sectional study of 3.9 + 3.2 mg/dL) in addition to proteinuria. The time elapsed between proteinuria appearance and the onset of renal insufficiency was 4.1 +/- 4.3 years. Renal insufficiency showed a slowly progressive course in most of these patients. There were no significant differences between group I and group II patients in age, gender, renal function, or blood pressure at the time of nephrectomy. In contrast, group II patients showed a body mass index (BMI) that was significantly higher than group I at nephrectomy (31.6 +/- 5.6 vs. 24.3 +/- 3.7 kg/m(2), P < 0.001), at cross-sectional study (33.3 +/- 6.6 vs. 25.1 +/- 3.5 kg/m(2), P < 0.001), and throughout follow-up. Among the 14 obese (BMI > 30 kg/m(2)) patients at the time of nephrectomy, 13 (92%) developed proteinuria/renal insufficiency. In contrast, among the 59 patients with BMI < 30 kg/m(2), only 7 (12%) developed these complications (P < 0.001). Kaplan-Meier estimated probability of negative proteinuria and normal renal function 10 years after nephrectomy was 40 and 70%, respectively, in obese patients at nephrectomy. At 20 years after nephrectomy, these percentages were 8 and 35%, respectively. In contrast, in nonobese patients, the probability of negative proteinuria and normal renal function was 93 and 98%, respectively, at 10 years (P < 0.001) and 77 and 91%, respectively, at 20 years (P < 0.001). Multiple logistic regression analysis showed that the risk of developing renal disease was only statistically correlated with BMI at the time of unilateral nephrectomy (odds ratio 1.34, 1.03 to 1.76 CI). CONCLUSIONS: Obese patients are at risk for developing proteinuria and chronic renal failure after unilateral nephrectomy. Regular and long-term follow-up are recommended in these patients.  相似文献   
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