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Deoxycholic acid (DA) caused a dose-related release of histamine (HR) from mast cells of rat peritoneum (RPMC) and mucosal cells of guinea pig rectocolon (RCMC). In both cell populations, DA-induced HR was: (1) accompared by a parallel release of lactate dehydrogenase (LDH), (2) not affected by metabolic inhibitors, (3) dependent on time of incubation, temperature and pH, and affected by Ca++ concentration in RPMC but not in RCMC. DA-induced HR from RCMC may be involved in certain functional disorders of the colon.  相似文献   
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Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis, but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer, with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations (275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment of suramin’s activity in hormone-refractory prostate cancer. Received: 9 June 1995/Accepted: 18 March 1996  相似文献   
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Automobile air bag inflation-caused injuries to the chest, neck, and face, in particular the orbital contents, are infrequent but recognized. We report the occurrence of multiple digital fractures in the left hand of a 30-yearold male driver as a result of sudden air bag inflation. Continued monitoring of the potential hazards of this device is suggested.  相似文献   
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The Association of American Medical Colleges publishes an enormous database each year, which encompasses every conceivable category of medical education. This information covers high-school student premedical activities, medical school/student data, demographics of residents and fellows in training, a profile of medical school faculty according to academic rank and the enrollment of each medical school in the country. It is all categorized according to race, ethnicity and gender. Furthermore, it is a longitudinal survey and, therefore, valid comparisons can be made over long periods of time. The extensive coverage of African-American involvement in the system at all levels allows for healthcare planners, administrators, politicians and students/parents at all levels to use this as a roadmap for planning purposes. Much of the data is broken down according to individual states, thus enabling students to make better decisions about selecting private versus public institutions for their training. The data on residents in training and medical school faculty provides very useful information for healthcare planners, state and federal government officials, and medical school deans and university administrators interested in addressing diversity issues within their respective domains.  相似文献   
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Peh SC  Shaminie J  Tai YC  Tan J  Gan SS 《Histopathology》2004,45(5):501-510
AIMS: Follicular lymphoma is frequently associated with t(14;18)(q32;q21) translocation. This study was undertaken to determine the pattern of Bcl-2, CD10 and Bcl-6 expression in relation to t(14;18) translocation in follicular lymphoma from a cohort of a multi-ethnic Asian population. METHODS AND RESULTS: Sixty-two cases of follicular lymphoma were retrieved for immunohistochemistry, and t(14;18) translocation analysis by polymerase chain reaction and fluorescent in-situ hybridization techniques. Bcl-2 expression was present in 74% of the cases. CD10 expression was also relatively low (61%), with decreasing frequency of expression in high-grade tumours. Bcl-6 protein was expressed in most of the tumours (88%) regardless of the tumour grade. The t(14;18) translocation was detected in 46 cases (74%) with an extremely high rate of t(14;18) translocation in ethnic Indian cases (100%). CONCLUSION: The frequency of t(14;18) translocation in this series of follicular lymphomas was higher when compared with previous Asian reports, but in accordance with European and North American findings. CD10 expression is strongly associated with a t(14;18) translocation event, but the overall CD10 expression was relatively low, possibly due to the high proportion of high-grade tumours in the series. t(14;18) translocation was not associated with Bcl-2 or Bcl-6 expression.  相似文献   
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Background: A previous study of piglet lung growth (Mansell et. al. 1989. J. Appl. Physiol., 67:1422–1427) showed transient stiffness to changes in shape and volume immediately after birth. Later, elastic recoil was found to increase as the lung grew in weight and volume. The present study uses morphometry to test possible structural correlates of these two mechanical changes. Methods: Piglet lungs were fixed near full inflation via the airways during the immediate newborn period (6–12 hours, n=3), at 3–5 days (n=6), 25–30 days (n=5), and 80–85 days (n=3). Morphometry comprised arithmetic and harmonic mean thicknesses of alveolar septae and average mean surface curvature. Measurements of curvature and airspace volume were combined to differentiate alveolar expansion from septal proliferation as mechanisms for volumetric growth. Results: The unique mechanical behavior of the newborn lungs was associated with relatively thick alveolar septae. Marked thinning of the septae and resolution of the stiffness to shape and volume change had occurred by 3–5 days. An increase in elastic recoil during the first postnatal month was found to be associated with simple airspace expansion. The second and third months were characterized by septal proliferation and increase in arithmetic mean septal thickness but elastic recoil did not increase further. Harmonic mean septal thickness and airspace volume per gram of lung tissue did not change over the course of the study. Conclusions: 1) A relative stiffness to shape and volume change in freshly newborn piglet lung is associated with relatively thick alveolar septal walls; 2) postnatal development of piglet lung parenchyma involves septal lengthening and thinning followed by septal proliferation; 3) the initial phase of septal lengthening, rather than the later phase of septal proliferation, is associated with increase in parenchymal recoil. © 1995 Wiley-Liss, Inc.  相似文献   
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