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51.
Adrenal incidentalomas   总被引:7,自引:0,他引:7  
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53.
Six new cadinene sesquiterpenoids, xenitorins A-F (1-6), were isolated from the methylene chloride solubles of the Formosan soft coral Xenia puerto-galerae. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.  相似文献   
54.
Background: Although patients with differentiated thyroid cancer (DTC) of follicular cell origin usually have an excellent prognosis, some patients die from progressive tumor. Numerous postoperative criteria have been used to predict prognosis in patients with DTC. The purpose of this investigation was to determine whether the TNM and metastases, age, completeness of resection, invasion, size (MACIS) classifications predicted survival time and why patients died from DTC. The extent of initial treatment and causes of death were also evaluated in these patients who died from thyroid cancer.

Study Design: Between 1965 and 1995, 102 of 1,224 patients with DTC treated at the University of California at San Francisco (UCSF) and UCSF/Mount Zion Medical Centers died from DTC. Risk factors including age at diagnosis, gender, histologic characteristics, TNM and MACIS classifications, the intervals among initial treatment, recurrence, and death, and the initial and subsequent treatments were documented in these 102 patients.

Results: Among the 102 patients who died of DTC 50% were men and 50% were women. The mean age of patients with DTC at diagnosis was 58 years at recurrence, 62 and 65 years at death. Thirty percent of these patients initially had unilateral thyroid operations and 70% had a bilateral operation. Tumors at presentation ranged from 0.6 to 13.0 cm (mean 4.4 cm); 46% of patients presented with late-stage tumors (TNM stage III, IV; MACIS score > 8). At presentation 46% of the patients had locally recurrent disease or regional metastases and 18% had distant metastases. Patients with persistent disease had a significantly shorter survival time than those with recurrent disease (p < 0.001). Both TNM and MACIS classifications were good predictors of survival time. Reoperations were performed in 51% of papillary, 26% of follicular, and 67% of Hürthle cell thyroid cancer patients. Fifty percent of patients with papillary thyroid cancer, 50% of patients with Hürthle cell thyroid cancer, and 11% of patients with follicular cell thyroid cancer died of locally advanced disease.

Conclusions: As expected, patients with local or regional recurrence and those with TNM stage I or MACIS score < 6 survived longer than patients with distant metastasis and TNM stage III or IV, MACIS score > 6, but some patients thought to be at low risk (TNM stage I; MACIS < 6) also died from thyroid cancer.  相似文献   

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A new cytotoxic lobane diterpene, ineleganene (1), was isolated from the Formosan soft coral Sinularia inelegans. The structure of compound 1 was determined by 1D and 2D spectral analysis.  相似文献   
57.
1. Magnolol is an active component of Magnolia officinalis. It is 1000-times more potent than α-tocopherol in inhibiting lipid peroxidation in rat heart mitochondira. In the present study, the in vivo antiarrhythmic and anti-ischaemic effects of magnolol in coronary ligated rats were investigated. 2. Male Sprague-Dawley rats were anaesthetized with urethane. Magnolol, at dosages of 10?7, 10?8 and 10?9 g/kg, was adminstered intravenously 15 min before ligation of the coronary artery. 3. The incidence and duration of ventricular tachycardia and ventricular fibrillation during 30 min coronary ligation were significantly reduced by magnolol. Ventricular arrhythmias during 10 min reperfusion after the relief of coronary ligation were also reduced. 4. In rats subjected to 4h coronary ligation, 10?7 and 10?8 g/kg magnolol significantly reduced infarct size. 5. We conclude that magnolol may protect the myocardium against ischaemic injury and suppress ventricular arrhythmia during ischaemia and reperfusion.  相似文献   
58.
A new experimental model for secondary hyperparathyroidism   总被引:2,自引:0,他引:2  
We have developed an animal model to study the pathogenesis of secondary hyperparathyroidism by inducing stable uremia in Sprague-Dawley rats by selective microligation of terminal branches of the left renal artery, followed by right nephrectomy. After 4 weeks the animals were killed, the parathyroid glands were removed and weighed, and blood samples were obtained. Of 30 rats, uremia developed in 22 (73%; uremic group) and eight (27%) died or did not become uremic. A sham-operated group of 15 rats served as control (control group). Creatinine levels were 1.8 +/- 0.5 mg/dl in the uremic group versus 0.5 +/- 0.1 mg/dl in the control group (p less than 0.0001). Parathyroid glands were hyperplastic in all rats with uremia and were heavier than parathyroid glands of control animals (70.3 +/- 26 vs 19.1 +/- 8 micrograms; p less than 0.0001). In the group with uremia, parathyroid hormone levels were increased over those of the control group (112.6 +/- 13 vs 28.9 +/- 6.2 pg/ml; p less than 0.0001), whereas osteocalcin levels were similar (36.6 +/- 11 vs 37.5 +/- 1 ng/ml). Serum calcium, phosphate, and alkaline phosphatase levels were similar in both groups. Our model can be used to test hypotheses concerning the treatment of secondary hyperparathyroidism and the relative pathogenetic relevance of vitamin D deficiency and phosphate retention.  相似文献   
59.
Chou HC  Chen JJ  Duh CY  Huang TF  Chen IS 《Planta medica》2005,71(11):1078-1081
A new acetophenone derivative, melicopone, along with twenty-nine known compounds has been isolated from the root wood of Melicope semecarpifolia. The structure of this new compound was determined using spectral analyses. The compound oxynitidine isolated in this study adds the Melicope genus to the benzo[c]phenanthridine-containing members chemotaxonomically. Three isolates were cytotoxic in P-388 and HT-29 cell lines, and anti-platelet aggregation activities were shown for 10 known compounds.  相似文献   
60.
Chen JJ  Lee HH  Duh CY  Chen IS 《Planta medica》2005,71(10):970-973
Two new dihydrochalcones, 2',4'-dihydroxy-3'-methoxydihydrochalcone, (-)-3'-methoxy-2',4',beta-trihydroxydihydrochalcone, a new flavanone, (2 S)-(-)-5'-hydroxy-7,3',4'-trimethoxyflavanone, and a new flavonol derivative, muntingone, along with sixteen known compounds, were isolated from the leaves of Muntingia calabura. The structures of these new compounds were determined using spectral analyses including extensive 2D NMR data. Among the isolates, (2 S)-5'-hydroxy-7,3',4'-trimethoxyflavanone, 4'-hydroxy-7-methoxyflavanone, 2',4'-dihydroxychalcone, and 2',4'-dihydroxy-3'-methoxychalcone exhibited cytotoxicity (IC (50) values < 4 microg/mL) against P-388 and/or HT-29 cell lines in vitro.  相似文献   
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