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报道新化合物A-失碳-17β-羟基-17α-乙炔基-Δ3(5),9(10)-雌甾二烯-2-酮2的合成。文中探讨了用炔钾粗品对A-失碳-Δ3(5),9(10)-雌甾二烯-2,17-二酮1和A-失碳-6β,19-环氧-Δ3-雄甾-2,17-二酮3的选择性炔化,分别得标题化合物2(44%)及A-失碳-17β-羟基-17α-乙炔基-6β,19-环氧-Δ3雄甾-2-酮4(65%),4经还原性破开环氧、去羟甲基和去醋酰氧基合成了标题化合物2。四步总收率为34%。 相似文献
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Two modified helical basket extractors are described that have increased the success rate of removing ureteral calculi using fluoroscopy from 63% to 92%. Initially a rather stiff and expandable basket with a 20-cm filiform tip is used with coaxial catheters and sheath (stage 1). If this procedure is unsuccessful, a basket with two long cable ends is passed from the nephrostomy out through the urethra (stage 2). When used with coaxial bladder catheters, this technique allows dilatation of the vesicoureteric junction and retrograde catheterization and injection of fluids or gas to dislodge the stone prior to extraction. In a series of 38 patients, stones were removed in all but three (a success rate of 92%). In five cases small stones (less than 5 mm) were not retrieved but subsequent studies were normal. Ureteral stones were found in the abdominal ureter in 28 cases, in the pelvic ureter in seven cases, and in multiple sites in three cases. Stones were larger than 1 cm in 27.7% of cases. Postextraction mucosal edema with reduced ureteral patency was common but usually cleared in 2-3 days. Occasional complications were related to the nephrostomy. 相似文献
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Retrorenal colon: implications for percutaneous diskectomy 总被引:1,自引:0,他引:1
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary. 相似文献
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C. Calatozzolo A. Salmaggi B. Pollo F.L. Sciacca M. Lorenzetti A. Franzini A. Boiardi G. Broggi C. Marras 《Neurological sciences》2007,28(6):304-310
Recent studies have shown an anti-tumour activity of cannabinoid receptors CB1 and CB2 in gliomas. This effect was mediated
by neurotrophins in breast and prostate carcinoma, while in gliomas this relationship has not yet been considered. The aim
of this study was to investigate the expression of cannabinoid receptors CB1 and CB2, neurotrophin NGF and NT-3 and their
receptors TrkA and TrkC in glioma and endothelial cells. The analysis was performed in 14 gliomas and 2 non-tumour brain specimens
by immunohistochemistry and real-time quantitative-polymerase chain reaction (RTQ-PCR). Gliomas showed a weak immunoreactivity
for CB1 and CB2 in tumour and in endothelial cells, and for NGF/TrkA mainly in tumour cells, while a moderate/diffuse immunoreactivity
was found for NT-3/TrkC. CB2 was expressed on 3 out of 6 low-grade gliomas and in all high-grade gliomas. Non-tumour brain
tissues were weakly positive in astrocytes and endothelium for CB1, CB2, NT-3 and TrkC and negative for NGF and TrkA. By RTQ-PCR,
gliomas showed low mRNA levels of NGF/TrkA and moderate levels of CB1, NT-3 and TrkC. CB2 mRNA expression was low or absent.
A potential role of cannabinoids, particularly of CB2 agonists devoid of psychotropic side effects, in glioma therapy could
have a basis in glioblastomas, because they were all positive, though weakly, to CB2. The presence of neurotrophins and their
receptors, mainly NT-3 and TrkC, suggests a possible role of these pathways in glioma growth/invasion, but further investigations
are required to verify this hypothesis and a potential relationship between cannabinoids and neurotrophins. 相似文献
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A Sgalambro A Marras F Lombardi C Guasconi G Schiavone G Sportelli S Del Giudice C Marinoni 《Giornale italiano di cardiologia》1987,17(8):667-672
Tricuspid regurgitation (TR) is detected by Doppler echocardiography in a high proportion of patients with right ventricle pressure or volume overload. Continuous wave Doppler (CW) provides a noninvasive estimation of the transtricuspid systolic pressure gradient, applying the modified Bernoulli formula to the maximum velocity of the TR jet. The purpose of this study was to test the accuracy of the CW prediction of systolic right ventricular pressure (RVPs), obtained adding a clinical estimate of the mean right atrial pressure (RAPm) to the Doppler derived pressure gradient. The study population consisted of 22 adult patients with Doppler proved TR, undergoing right heart catheterization (cath) for mitral valve disease (12 pts), atrial septal defect (8 pts), dilated cardiomyopathy (1 pt) or pulmonary hypertension (1 pt). Two studies were duplicated after nifedipine administration. TR was graded by pulsed Doppler flow mapping as mild in 7, moderate in 11, severe in 4 pts. RAPm was estimated clinically from the inspection of neck veins pulsatility (mmHg = pulsatility cm+5/1.3). At CATH RVPs ranged from 27 to 80 (46 +/- 17) mmHg, RAPm from 0 to 13 (6 +/- 3) mmHg. RVPs Doppler prediction showed a close correlation with CATH (r .97, SEE 4.2 mmHg), with a slight mean underestimation (-2 +/- 4 mmHg) (Fig. 3, Tab. I). The discrepancies between CW and CATH ranged from -9 to +10 mmHg, almost entirely due to inaccuracy of the RAPm clinical estimate (r .48, see 3.8 mmHg) (Fig. 4, Tab. I).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献