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71.
研究了双茂基希夫碱稀土络合物/NaH体系催化1,5-己二烯的异构化反应。异构化反应生成1,4-己二烯、2,4-己二烯、1,3-己二烯、亚甲基环戊烷和甲基环戊烯的混合物。同时研究了异构化反应中不同催化剂、反应温度、催化剂用量和时间对异构化速率及产品组成的影响。产物中线型产物与环状产物的比率取决于所用的催化剂及反应条件。 相似文献
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Stimulation of amylase secretion from parotid glands by beta-adrenergic agonists is mediated by the activation of adenylate cyclase and the resultant increase in cellular cAMP. Since NaF is known to increase adenylate cyclase activity and cAMP accumulation in intact cells, we investigated whether it would stimulate amylase secretion from isolated rat parotid gland cells. The results provide evidence that the addition of NaF (0.01-10 mmol/L) increased cAMP concentration (1.5-2.8-fold) in, and amylase secretion (16-93%) from, isolated parotid gland acinar cells. NaF was found to increase cAMP-dependent protein kinase activity ratios (51-84%) in a concentration- and time-dependent manner. The data suggest that the stimulation of amylase secretion from parotid gland cells by NaF may be mediated by an increase in the cellular cAMP concentration, which exerts its effect, at least in part, by increasing the activity of cAMP-dependent protein kinase. 相似文献
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Stephanie R. Rice Jason K. Molitoris Melissa A.L. Vyfhuis Martin J. Edelman Whitney M. Burrows Josephine Feliciano Elizabeth M. Nichols Mohan Suntharalingam James Donahue Shamus R. Carr Joseph Friedberg Shahed Badiyan Charles B. Simone Steven J. Feigenberg Pranshu Mohindra 《Clinical lung cancer》2019,20(1):e107-e114
Background
We questioned whether the National Comprehensive Cancer Network recommendations for brain magnetic resonance imaging (MRI) for patients with stage ≥ IB non–small-cell lung cancer (NSCLC) was high-yield compared with American College of Clinical Pharmacy and National Institute for Health and Care Excellence guidelines recommending stage III and above NSCLC. We present the prevalence and factors predictive of asymptomatic brain metastases at diagnosis in patients with NSCLC without extracranial metastases.Materials and Methods
A retrospective analysis of 193 consecutive, treatment-naïve patients with NSCLC diagnosed between January 2010 and August 2015 was performed. Exclusion criteria included no brain MRI staging, symptomatic brain metastases, or stage IV based on extracranial disease. Univariate and multivariate logistic regression was performed.Results
The patient characteristics include median age of 65 years (range, 36-90 years), 51% adenocarcinoma/36% squamous carcinoma, and pre-MRI stage grouping of 31% I, 22% II, 34% IIIA, and 13% IIIB. The overall prevalence of brain metastases was 5.7% (n = 11). One (2.4%) stage IA and 1 (5.6%) stage IB patient had asymptomatic brain metastases at diagnosis, both were adenocarcinomas. On univariate analysis, increasing lymph nodal stage (P = .02), lymph nodal size > 2 cm (P = .009), multi-lymph nodal N1/N2 station involvement (P = .027), and overall stage (P = .005) were associated with asymptomatic brain metastases. On multivariate analysis, increasing lymph nodal size remained significant (odds ratio, 1.545; P = .009).Conclusion
Our series shows a 5.7% rate of asymptomatic brain metastasis for patients with stage I to III NSCLC. Increasing lymph nodal size was the only predictor of asymptomatic brain metastases, suggesting over-utilization of MRI in early-stage disease, especially in lymph node-negative patients with NSCLC. Future efforts will explore the utility of baseline MRI in lymph node-positive stage II and all stage IIIA patients. 相似文献76.
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Sanda Alexandrescu James P. Orengo Shahed Toossi Arie Perry Patrick Treseler Christopher Hess Marta Margeta 《Neuropathology》2015,35(2):170-174
Intravascular large cell lymphoma (IVLCL) is a rare disease characterized by proliferation of malignant lymphocytes within the small blood vessel lumens. The association of IVLCL with autoimmune hemolytic anemia (AIHA) has been described in a single case report, but the true prevalence of this co‐occurrence is not known because of declining autopsy rates. Here, we report a case of a 41‐year‐old woman who carried a diagnosis of AIHA for 2 years, with repeated hemolytic episodes that were initially well controlled with immunomodulatory treatment. At her last presentation, the patient developed rapidly progressive neurologic symptoms and leukoencephalopathy on MRI; she died 4 weeks later with a clinical impression of thrombotic microangiopathy, a known complication of AIHA. At autopsy, the brain showed widespread platelet thrombi and intraparenchymal hemorrhages characteristic of this disorder. In addition, there was evidence of a clinically unsuspected IVLCL, most likely of B‐cell lineage. This case illustrates a potential association between IVLCL and AIHA, highlights the need for broad differential diagnosis in cases with atypical disease presentation or progression, and underlines the importance of autopsy in establishing the full cause of morbidity and mortality. 相似文献
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