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1.
PurposeOur purpose was to determine the effect of chemoradiotherapy (CRT) on patient-reported quality of life (QOL) for patients with intact pancreas cancer.Methods and MaterialsWe reviewed a prospective QOL registry for patients with intact, clinically localized pancreatic ductal adenocarcinoma treated with CRT between June 2015 and November 2018. QOL was assessed pre-CRT (immediately before CRT, after neoadjuvant chemotherapy) and at the completion of CRT with the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) and its component parts: FACT-General (FACT-G) and hepatobiliary cancer subscore (HCS). A minimally important difference from pre-CRT was defined as ≥ 6, 5, and 8 points for FACT-G, HCS, and FACT-Hep, respectively.ResultsOf 157 patients who underwent CRT, 100 completed both pre- and post-CRT surveys and were included in the primary analysis. Median age at diagnosis was 65 years (range, 23-90). National Comprehensive Cancer Network resectability status was resectable (3%), borderline resectable (40%), or locally advanced (57%). Folinic acid, 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) (75%) or gemcitabine and nab-paclitaxel (42%) were given for a median of 6 cycles (range, 0-42) before CRT. Radiation therapy techniques included 3-dimensional conformal (22%), intensity modulated photon (55%), and intensity modulated proton (23%) radiation therapy to a median dose of 50 Gy (range, 36-62.5). Concurrent chemotherapy was most commonly capecitabine (82%). Sixty-three patients (63%) had surgery after CRT. The mean decline in FACT-G, HCS subscale, and FACT-Hep from pre- to post-CRT was 3.5 (standard deviation [SD], 13.7), 1.7 (SD 7.8), and 5.2 (SD 19.4), respectively. Each of these changes were statistically significant, but did not meet the minimally important difference threshold. Pancreatic head tumor location was associated with decline in FACT-Hep. Nausea was the toxicity with the greatest increase from pre- to post-CRT by both physician-assessment and patient-reported QOL.ConclusionsFor patients with intact pancreatic adenocarcinoma, modern CRT is well tolerated with minimal decline in QOL during treatment.  相似文献   
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神经生长因子对小鼠突触体内Ca^2+水平的调节作用   总被引:4,自引:1,他引:3  
徐晓虹  郭丹 《药学学报》1997,32(10):731-734
观察了多次海马内微注射NGF对小鼠突触体内游离钙水平的影响,并在离体情况下观察NGF对EGTA和CaCl2分别造成突触体内低钙和高钙状态的调节作用。结果如下:(1)在体实验表明,一定剂量的NGF可显著降低老年小鼠海马突触体内游离钙水平(P<005);(2)离体实验表明,当突触体游离钙水平降低时,适当剂量的NGF具有升高游离钙水平的作用;而突触体内游离钙水平升高时,则NGF有降低游离钙水平的作用。提示NGF对游离钙水平的双向调节作用可能是NGF改善老年性记忆衰退的作用机制。  相似文献   
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5-(2-Acylethynyl)-2,4-dimethoxypyrimidines (3-6) were synthesized in excellent yields from 2,4-dimethoxy-5-[2-(trimethylsilyl)ethynyl]pyrimidine (2) by treatment with acid chlorides in the presence of anhydrous aluminum chloride. Compounds 3-6 were deblocked with chlorotrimethylsilane and sodium iodide in acetonitrile to the corresponding 5-[(2-acyl-1-iodo)vinyl]uracils (7-10), which on treatment with potassium hydroxide in dioxane yielded the corresponding 5-(2-acylethynyl)uracils (11-14). The 5-(2-acylethynyl)uracils were found to be active against Ehrlich ascites carcinoma (EAC) cells in vivo, the most active compounds being 5-(2-benzoylethynyl)uracil (11) and 5-(2-p-toluoylethynyl)uracil (12). The T/C values of 281 and 300 were obtained for compounds 11 and 12, respectively, in the case of mice bearing EAC cells. The 5-(2-acylethynyl)uracils have also shown in vitro activity against CCRF-CEM and L1210/0 tumor cell lines. The lead compound 5-(2-p-toluoylethynyl)uracil effectively inhibited thymidylate synthetase.  相似文献   
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Anaphylactoid reaction to syntocinon?   总被引:2,自引:0,他引:2  
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Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.  相似文献   
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Summary Dipyridamole (DP) has previously been studied both in vitro and in vivo in combination with various antimetabolites, including methotrexate and 5-fluorouracil (5FU). We evaluated in vitro and clinically the effects of adding DP to fluorodeoxyuridine (FUDR) in colorectal cancer. Using a human colony-forming assay, we observed that 0.05 M DP increased the cytotoxicity of FUDR by a median of 33.5-fold vs 1.5-fold for 5FU against human colon-cancer cell lines. The mechanism of the DP-enhanced antitumor activity of FUDR is not completely understood but appears to be related to a profound inhibition by DP of thymidine accumulation in and FUDR efflux from colon-cancer cell lines. On the basis of these in vitro results, 28 patients with metastatic colon cancer were entered in a clinical trial of monthly courses of 0.1 mg/kg FUDR daily for 14 days and 75 mg oral DP 5 times daily for 14 days starting on the 3rd day of continuous i.v. FUDR infusion. The pharmacokinetics of DP was studied in three patients; the results showed that 98% of total serum DP was protein-bound and that free DP levels were significantly lower than the concentrations necessary for the expected in vitro DP/FUDR modulation. Treatment was well tolerated, with only 12 patients developing mild to moderate toxicity. Of 27 evaluable patients, 4 achieved a partial response that lasted 2, 3, 5, and 6+ months. This relatively low response rate (15%), which is similar to that achieved with FUDR alone, may be explained by the low steady-state plasma concentrations of free DP achieved in our patients. Other means of DP administration, such as i.v., i.a., and i.p. injection, may be required to achieve free DP concentrations necessary for successful biochemical modulation of FUDR in patients.Supported in part by grants CA17094, CA23074, and CA39629 from the National Institutes of Health, Bethesda, Md 20205, and a grant from the Arizona Chronic Disease Commission. HSG is a recipient of an American Cancer Society Career Development Award  相似文献   
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The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.   相似文献   
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To explore the structural basis of alternative splicing, we have analyzed the splicing of pre-mRNAs containing an optional exon, E4, from the preprotachykinin gene. This gene encodes substance P and related tachykinin peptides by alternative splicing of a common pre-mRNA. We have shown that alternative splicing of preprotachykinin pre-mRNA occurs by preferential skipping of optional E4. The competing mechanism that incorporates E4 into the final spliced RNA is constrained by an initial block to splicing of the immediate upstream intervening sequence (IVS), IVS3. This block is relieved by sequential splicing, in which the immediate downstream IVS4 is removed first. The structural change resulting from the first splicing event is directly responsible for activation of IVS3 splicing. This structural rearrangement replaces IVS4 sequences with E5 and its adjacent IVS5 sequences. To determine how this structural change promoted IVS3 splicing, we asked what structural change(s) would restore activity of IVS3 splicing-defective mutants. The most significant effect was observed by a 2-nucleotide substitution that converted the 5' splice site of E4 to an exact consensus match, GUAAGU. Exon 5 sequences alone were found not to promote splicing when present in one or multiple copies. However, when a 15-nucleotide segment of IVS5 containing GUAAGU was inserted into a splicing-defective mutant just downstream of the hybrid exon segment E4E5, splicing activity was recovered. Curiously, the 72-nucleotide L2 exon of adenovirus, without its associated 5' splice site, activates splicing when juxtaposed to E4. Models for the activation of splicing by an RNA structural change are discussed.  相似文献   
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