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201.
A new simply and effective fractionation method for cylindrospermopsin (CYN) analyses was developed. The extract from cells of Cylindrospermopsis raciborskii was resuspended with 0.1 M carbonate buffer at pH 10.5, and pass through the double-cartridges column which was consisted of a styrene polymer cartridge and an anion exchange cartridge. CYN and deoxy-CYN were adsorbed with the anion exchange cartridge. After separation of the anion exchange cartridge, adsorbed compounds were eluted from the cartridge with 50% methanol containing 1% formic acid solution. CYN and deoxy-CYN were selectively condensed in the eluted solution. When CYN was analyzed by LC-photodiode array or LC/MS, only two peaks of CYN and deoxy-CYN were detected quantitatively. The results suggest that the fractionation method is a useful method for CYN analyses and must be utilized for CYN purification.  相似文献   
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PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B.  相似文献   
203.
We report a very rare case of primary gastric small cell carcinoma (GSCC) that was accompanied with gastric tubular adenocarcinoma. A male in his 60s had an elevated tumor with a central ulceration in the middle stomach. The patient underwent a distal gastrectomy with lymph node dissection. The pathological examination showed two separated lesions of the stomach, which contained the components of primary GSCC and primary gastric tubular adenocarcinoma. Immunohistochemical (IHC) examination demonstrated that the tumor cells in the small cell carcinoma stained positive for synaptophysin, chromogranin A, and neural cell adhesion molecule (NCAM). GSCC cells and adenocarcinoma cells independently metastasized to each regional lymph node. Further studies on the biological behavior of individual tumors may allow the development of new treatment strategies for GSCC.  相似文献   
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Objective We investigated whether available epidemiological and toxicological data suggest an increased risk of mesothelioma among workers exposed to synthetic vitreous fibers (SVF). Methods We conducted a systematic review of epidemiological studies on the risk of mesothelioma among workers exposed to SVF, and toxicological studies on SVF and mesothelioma. Results Seven cohort studies were conducted among workers employed in production of rock/slag wool, glass wool, or continuous glass filament in the United States, Canada, and Europe. Of the six deaths from mesothelioma identified in these studies, three had exposure to asbestos. A review of death certificates in a study of rock wool production workers identified one additional probable death. A formal comparison with expected deaths is not feasible. Four community-based case–control studies were identified, of which three reported an increased risk among SVF-exposed workers. The number of cases not exposed to asbestos was less, and residual confounding from asbestos exposure misclassification may explain the association in these studies. The toxicology review of SVF suggested that they present a low hazard mostly due to their low biopersistence, typically with a half-life in rat studies of tens of days compared to amphibole asbestos which has a half-life of 400–500 days. Conclusions The combined evidence from epidemiology and toxicology provide little evidence that exposure to SVF increases the risk of mesothelioma.  相似文献   
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This study investigated the ability of negatively versus positively perceived stress to predict outcome of treatment for binge eating disorder (BED). Participants were 62 obese women satisfying the DSMIV research criteria for BED. Stress was measured using an instrument based on the Recent Life Change Questionnaire (RLCQ). Participants experiencing high negative stress during the study period reported a binge eating frequency three times greater than that reported by subjects experiencing low negative stress (2.14 vs. 0.65 binge-days/week). Negative stress predicted how fast an individual would reduce binge eating and demonstrated more predictive power than positive stress.  相似文献   
208.
Abstract

A highly specific and sensitive competitive radioimmunoassay was developed for caerulein (CLN), an analogue of cholecystokinin-8 (CCK-8), in plasma and brain. Antiserum was produced in rabbit by immunization with Nδ-[CLN-(1-6)]-ornithine amide conjugated with bovine serum albumin by the glutaraldehyde method. Nα-[CLN-(1-6)]-lysine amide was labelled with 125I-Bolton & Hunter reagent and used as a labelled antigen after purification by high-performance liquid chromerography. This assay was highly specific for CLN, and cross reactivities for other related peptides, CCK-4, CCK-8, gastrin-I, and gastrin-(14–17), were not observed (<0.01%). The limits of determination in biological specimens after CLN administration were 11 pg/ml in human plasma and rat plasma and 80 pg/g in rat brain. This study showed that the slight structure difference between hapten and 125I-labelled antigen is important to the assay performance.  相似文献   
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