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141.
Gu Leo C. Erdös Elizabeth A. Chiang Hi-Shi Calderwood Thomas Tsai Kelly Visor Gary C. Duffy Jane Hsu Wen.-C. Foster Linda C. 《Pharmaceutical research》1991,8(4):485-490
The thermal stability of IL-1 in aqueous solution as a function of temperature (5–60°C), pH (2–9), buffer (acetate, citrate, tris, and phosphate), and cyroprotectants (sugars, HSA) was investigated in this study. The analytical methodologies included RP-HPLC, SEC, ELISA, IEF-PAGE, SDS-PAGE, and bioassay. The degradation and inactivation of IL-1 at or above 39°C were attributed to autoxidation of the two cysteine residues in the denatured protein, followed by hydrophobic/covalent aggregation and precipitation. At or below 30°C, IEF- and SDS-PAGE results suggest a possible deamidation reaction. The difference in mechanism of degradation precludes the prediction of formulation shelf life from accelerated temperature data. Nonetheless, the good stability observed at 5°C suggests that a solution formulation may be feasible for IL-1. 相似文献
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143.
A new method is described for recording the emotion-induced decrease in skin resistance area, which is known as the skin-resistance response (SRR). The method employs a simple current source and a new type of tetrapolar electrode in which the SRR is measured with the non-current-carrying electrodes. The signal produced can be recorded with a standard electrocardiograph. Typical SRRs from two subjects are presented. 相似文献
144.
The effects of aging on the responsiveness of hippocampal neurons to iontophoretic application of L-glutamate and AMPA were studied in vitro. There were no effects of age on neuronal responses to L-glutamate; however, CA1 pyramidal cells of old rats, but not granule cells in the fascia dentata, showed both a smaller reduction in extracellularly-recorded synaptic responses following application of AMPA (presumably mediated by depolarization), and smaller extracellular "DC" fields (measured by subtracting the DC potentials at the dendrite and soma following AMPA application in the dendrites). To examine the cellular bases of this age-related alteration in AMPA sensitivity, two additional electrophysiological approaches were used: (1) measurement of the amplitude ratios of extracellular EPSP and fiber potential components of the Schaffer collateral-CA1 response; (2) measurement of intracellularly recorded unitary EPSPs and quantal analysis of their fluctuations. The interpretations that would be placed on four hypothetical possible outcomes of such experiments are outlined and assessed in relation to the experimental data. The pattern of results obtained in the present experiments supports the following conclusions: In old rats, individual Schaffer collateral synapses do not appear to have altered AMPA receptor properties, as neither the mean size of the unitary synaptic response nor the apparent quantal size differs between age groups; however, the data do support the conclusion that there are fewer synapses per Schaffer collateral branch in old versus young CA1 pyramidal cells. 相似文献
145.
The Colorado Client Assessment Record (CCAR) is a problem checklist and level of functioning rating instrument used to describe admission to a public mental health system. A brief, non-technical summary of recent research and administrative applications involving this instrument is presented. A stable factor structure, generalizable to several diverse client populations, is reported. Scaling procedures for measuring these procedures and a client typology based on this scaling are described. The client typology is differentially related to the types of services received and the costs of treatment episodes. The typology is also used to understand differences in case mixes and lengths of stay at two state hospitals. 相似文献
146.
The addition of supplementary cytosolic fraction greatly enhancesthe activation of 2-acetylamlnofluorene (AAF) by uninduced 9,000x g supernatant fraction (S9) in the Ames test. Uninduced S9is poor at activating AAF in the Ames test (although it is effectivein the liquid based fluctuation test) probably because cytosolizmaterial diffuses into the bottom agar. An enhancing effectof cytosol supplementation was also observed with 2-aminoanthracene(AA) and 2-aminofluorene (AF) with uninduced S9. Using Aroclor-inducedpreparations, supplementation with cytosol enhanced the activationof benzo[a]pyrene and ethidium bromide. With AAF and Aroclor-inducedpreparations, supplementation with cytosol produces a slightbut significant increase in activation, but interpretation iscomplicated by the fact that Aroclor 105,000 x g supernatantfraction (S105) alone efficiently activates AAF, AF and AA.Norharman potentiated the enhancing effect of Arodor S105 onArodor-S9 activation of AAF but inhibited the activation ofAAF by S105 fraction alone. The enhancing effect of S105 fractionmay explain some, but not all, of the differences between liquidbased and agar overlay based activation. 相似文献
147.
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149.
Steven R Alberts Mark Schroeder Charles Erlichman Preston D Steen Nathan R Foster Dennis F Moore Kendrith M Rowland Suresh Nair Loren K Tschetter Tom R Fitch 《Journal of clinical oncology》2004,22(24):4944-4950
PURPOSE: Gemcitabine remains the standard therapy for metastatic pancreatic adenocarcinoma (ACA), but has limited activity. ISIS-2503 is an antisense compound directed against H-ras with preclinical activity against pancreatic ACA in tumor models. The combination of ISIS-2503 and gemcitabine has been evaluated in a prior phase I study. METHODS: Patients with metastatic or locally advanced pancreatic ACA not amenable to surgery or local radiation received gemcitabine 1,000 mg/m(2) intravenously over 30 minutes on days 1 and 8 and ISIS-2503 6 mg/kg/d as a continuous intravenous infusion over 14 days of an every-3-weeks cycle. Responses were monitored by radiologic imaging every 6 weeks. RESULTS: Forty-eight eligible patients were enrolled, 43 with metastatic disease. Median follow-up was 12.6 months (range, 2.2 to 16.8 months) for living patients. A median of four cycles of treatment was given (range, 1 to 18 cycles). All patients were assessable for response and toxicity. The 6-month survival percentage was 57.5% (95% CI, 44.9% to 73.5%) and the median survival was 6.6 months. The response rate was 10.4% (one complete response, four partial responses). Clinically significant toxicity was limited except for one fatal pulmonary embolism. CONCLUSION: This study shows a promising response rate to the combination of gemcitabine and ISIS-2503 in patients with pancreatic ACA. The observed 6-month survival rate in these patients met our protocol-defined criteria for success. This regimen is tolerable, but is of unclear benefit. Additional studies evaluating the role of gemcitabine and ISIS-2503 in the treatment of pancreatic ACA should be considered. 相似文献
150.
The pathology of late recurrence of testicular germ cell tumors 总被引:16,自引:0,他引:16
Michael H Lucia J Foster RS Ulbright TM 《The American journal of surgical pathology》2000,24(2):257-273
A total of 91 men had histologically documented late recurrences of testicular germ cell tumors characterized by a complete response to treatment with a subsequent disease-free interval of at least 2 years and no evidence of a second primary lesion. Ninety percent of the patients for whom information was available received chemotherapy shortly after their initial diagnosis of testicular germ cell tumors; most of the other patients were known to have stage I disease initially. Overall, 60% of patients had teratoma in their late recurrences, including 20 patients (22%) in whom teratoma was the only element. Thus, teratoma was the most common type of neoplasm in late recurrences. Excluding teratoma coexisting with other types of neoplasms, yolk sac tumor was the most frequent type of tumor in patients with late recurrence. It occurred in 47% of patients, either alone or with teratoma, another nonteratomatous germ cell tumor type, or a "nongerm cell malignant tumor." Unusual types of yolk sac tumor, including glandular, parietal, clear cell, and pleomorphic patterns, were seen frequently in late recurrences and often raised differential diagnostic problems with "nongerm cell" carcinomas. A smaller number of late recurrences consisted of other types of neoplasms. Twenty percent of patients with late recurrence had a nonteratomatous germ cell tumor other than yolk sac tumor, either alone, with yolk sac tumor, or with a "nongerm cell malignant tumor." Most of these nonteratomatous germ cell tumors other than yolk sac tumor were embryonal carcinoma, although rarely seminoma and choriocarcinoma were encountered. "Nongerm cell malignant tumors," including both sarcomas and carcinomas of various types, occurred in 23% of late-recurrence patients, either alone or with a nonteratomatous germ cell tumor. Late recurrences were seen in many different sites in these patients, including the retroperitoneum, abdomen, pelvis, liver, mediastinum, lung, bone (femur, vertebra, and rib), lymph nodes outside the retroperitoneum and mediastinum (supraclavicular, neck, and axillary regions), scrotum and inguinal regions, adrenal gland, chest wall, and buttocks. Follow-up data were available for 79 of the 91 patients studied. Duration of follow-up ranged from 2 months to 13 years after the patient's first late recurrences; the mean length of follow-up was 4.8 years. Patients whose late recurrences consisted of teratoma only had the most favorable outcomes, with 79% having no evidence of disease at last follow-up. Patients whose late recurrences consisted of pure "nongerm cell malignant tumor" or pure germ cell tumor (yolk sac tumor or other types) had a much worse prognosis: Only 36% to 37% were alive with no evidence of disease. Patients with two different types of nonteratomatous malignancies in their late recurrences had a dismal clinical course: Only 17% with both yolk sac tumor and other nonteratomatous germ cell tumor had no evidence of disease, whereas no patient with both nonteratomatous germ cell tumor and "nongerm cell malignant tumor" was disease free. Late recurrences consisting of teratoma alone often have a favorable outcome, but the prognosis in all other patients is poor. Furthermore, late recurrence is not likely to respond to chemotherapy and is best treated by surgical excision when possible. 相似文献