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181.
The leaf essential oil of Eugenia zuchowskiae from Monteverde, Costa Rica, has been obtained by hydrodistillation and analyzed by GC–MS. The principal constituents of E. zuchowskiae leaf oil were α-pinene (28.3%), β-caryophyllene (13.2%), α-humulene (13.1%), and α-copaene (8.1%). The leaf essential oil of E. zuchowskiae showed pronounced in-vitro cytotoxic activity against MCF-7, MDA-MB-468, and UACC-257 human tumor cell lines. The major components showed cytotoxic activities comparable to doxorubicin (LC50 14–70 μg/ml).  相似文献   
182.
Objective: To evaluate the effect and safety of clinical use of zoledronic acid in the treatment of malignant hypercalcemia. Methods: A multi-center, open phase II clinical trial was conducted in 15 cases with malignant hypercalcemia who received zoledronic acid intravenously for 15 min. The level of blood calcium and side effects were recorded regularly within 28 days after injection. Results: One case was dropped out due to bad compliance. The complete response rate (the corrected serum calcium was reduced to normal level) was 100.00% (14/14). The medium time of complete response rate was 5.07 days. The medium maintain time was 22.30 days. Slight, or moderate fever was observed. Conclusion: Zoledronic acid can effectively reduce the malignant hypercalcemia. The use of zoledronic acid appears to be safety and convenient.  相似文献   
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Dehydrochlorinated poly(vinylidene chloride) proved to be a conjugated polyene-polyene polymer. Shock compression of the polymer formed a large portion of graphite and trace amounts of diamond and of an unknown carbon. The unknown carbon belongs to the hexagonal crystal system and possesses the cell dimension α0 = 0.338 nm. A comparison with known carbynes was made in terms of the crystalline parameters.  相似文献   
185.
One hundred and thirty-four patients with vasoocclusive diseases were retrospectively tested for three kinds of antiphospholipid antibody (aPL). The mean age at onset of the disease in 58 patients with aPL was 43 years old. Seventeen, 11, and 9 patients were positive for the aCL IgA, IgM, and IgG isotypes, respectively. The rates of anti-phospholipid syndrome (APS) in patients with arterial (n=94), venous (n= 31), or both arterial and venous (n=9) occlusion were 45%, 29%, and 78%, respectively.The rates of APS in patients with autoimmune disease (n=13), thromboangiitis obliterans (TAO) (n= 36), arteriosclerosis obliterans (ASO) with lower leg involvement (n=8) or aortic arch syndrome (n=5), Raynaud's syndrome (n=15), aortitis syndrome (n= 13), ischemic heart disease (IHD) with young onset (n =12), and bilateral leg deep venous thrombosis (DVT) (n=10) were 77%, 46%, 13%, 80%, 40%, 62%, 33%, and 70%, respectively. The cumulative patency rate for reconstructive surgery in patients (n=13) with aCL was found to be considerably lower than that in those without aCL (n=13). From these results it was concluded that IgA was the most valuable aCL isotype for the diagnosis of APS and that aPL should be examined in patients with double-vessel occlusion, autoimmune disease, bilateral leg DVT, aortic arch syndrome, TAO, Raynaud's syndrome, or IHD with young onset. Furthermore, prophylaxis for graft failure is more strongly recommended for patients with aCL than for those without it.  相似文献   
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Ocular allergic reactions and inflammatory cascades in the eye involve various arachidonic acid metabolites. One such metabolite, leukotriene B4 (LTB4) was detected in bovine lenses after incubation in Tyrode's solution and analyzed by reverse phase and normal phase high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). LTB4, a product of the lipoxygenase pathway has a chemotactic potency, and may play an important role in the inflammatory cascade. Our results demonstrate the capacity of the bovine lens to synthesize LTB4. It is possible that LTB4 synthesized in lenses under some conditions plays an important role in ocular inflammatory and allergic reactions.  相似文献   
188.
The ontogeny of the behavioral effects of acute cocaine administration and behavioral sensitization to cocaine in rat pups was investigated. Acute behavior stimulating effects of cocaine were observed in pups as young as 7 postnatal days (PND) old, although they needed a higher dose of cocaine than adult rats to evoke the same motor effects. An adult dose-response curve pattern of stereotypy and locomotion to acute cocaine treatment was observed at PND 21, and of rearing at PND 28. Rats aged PND 7, 14, 21, 28, and 56 received repeated injections of saline or cocaine (15 mg/kg) twice a day for 5 consecutive days. After a 3-week period of abstinence, sensitization to a challenge dose of cocaine was assessed. Cocaine-induced stereotyped behavior was enhanced significantly only in rats in which cocaine pretreatment was initiated on PND 21, 28, and 56, but not earlier on PND 7 and 14. Adult female rats given repeated cocaine injections on PND 56–60 showed significantly greater sensitization than males, but no such sex difference was observed in pups given cocaine repeatedly on PND 21–25 or 28–32. These results show clearly that cocaine-induced behavioral sensitization in rats occurred only when subchronic cocaine administration was commenced on PND 21 or later.  相似文献   
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