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991.
992.
Pronounced differences in pharmacokinetic parameters of antipyrine have been found in the 20-day pregnant hooded Wistar rat when compared with nonpregnant controls. Total body clearance falls significantly from 5.93 to 3.5 ml/min/kg in the pregnant rat whereas no significant increase in antipyrine volume of distribution occurs. These changes result in an increase in antipyrine half-life from 109 to 223 min in the pregnant rat. This study demonstrates that reduced hepatic mono-oxygenase capacity exists in the pregnant rat and that this can markedly affect drug clearance in there animals. 相似文献
993.
目的分析胃肠系统淋巴瘤的CT、胃肠造影表现。材料与方法回顾性分析了20例胃肠系统淋巴瘤的胃肠道造影及CT影像资料,其中男16例,女4例,年龄25~71岁。20例均行胃肠道造影检查,15例行腹部CT检查。所有病例均经病理证实。结果1.胃肠道气钡造影检查①浸润型胃8例,小肠1例;②肿块型胃5例;③溃疡型胃2例;④息肉型近端空肠1例,末端回肠及盲肠3例。2.CT表现向心性壁厚20~25mm局限性肿块,脾大,脾内低密度灶2例;淋巴结增大。结论1.气钡双重造影是诊断胃肠系统淋巴瘤的首选方法,CT检查可以补充其他器官及淋巴结情况。2.胃肠系统淋巴瘤应与其他疾病相鉴别。 相似文献
994.
995.
In the present experiment we used immobilized progesterone linked to bovine serum albumin (P4-3-BSA) as a probe to examine whether the effects of a direct in vitro infusion of progesterone upon dopamine (DA) release from corpus striatal (CS) tissue fragments from ovariectomized estrogen-treated rats may be attributable to a surface membrane site of action. In Expt. I, a direct in vitro pulsatile infusion of P4-3-BSA resulted in two discrete episodes of stimulated DA release which were not observed in superfusions receiving a continuous infusion of P4-3-BSA or compared to data of control superfusions. In contrast to that of a pulsatile administration, a continuous infusion of P4-3-BSA completely abolished the amphetamine-stimulated response from these tissue preparations with significantly lower DA release rates compared to the pulsatile P4-3-BSA (P less than 0.02) and control (P less than 0.04) conditions. In Expt. II, the addition of tetrodotoxin (TTX, 1 microM) to the superfusion medium abolished the discriminatory response between pulsatile and continuous administration of immobilized progesterone. These results indicate that the action of progesterone on DA release from the CS is mediated primarily through a surface membrane site of an interneuron(s) which can discriminately respond to a specific infusion mode of this steroid. 相似文献
996.
997.
In the moth Manduca sexta, intersegmental muscles (ISMs) undergo rapid programmed cell death (PCD) within 48 hr of adult emergence. ISM PCD involves ubiquitin-dependent proteasomal degradation accompanied by the down-regulation of expression of actin genes and the up-regulation of degradative gene expression such as ubiquitin. Hemin chloride and N-acetyl-leu-leu-norleucinal (ALLN), both inhibitors of proteasomal activity, administered before adult emergence delayed PCD for up to 5 days in ISMs maintained from the larval stage, such as the dorsal internal medial muscle in abdominal segment 4 (DIM-A4). ISMs that developed during metamorphosis from respecified larval muscles such as the DIM-A2 were less dramatically affected. The increase in polyubiquitinated proteins and the decrease in actin mRNA expression accompanying maintained ISM PCD were delayed after inhibitor application. No changes were detected in respecified ISMs. These results reveal a regulatory role for proteasomal activity in an early stage of maintained ISM cell death. 相似文献
998.
Dr. Thomas N. Vahey MD Dr. Dean D. T. Maglinte MD Stanley M. Chernish MD 《Digestive diseases and sciences》1986,31(11):1192-1195
This report presents a comparison of state-of-the-art esophagography and endoscopy in the diagnosis of pathologically proven esophagitis. The modern multiphasic esophagogram is shown to have a sensitivity of 92% for the detection of opportunistic esophagitis in the immunocompromised patient. State-of-the-art esophagography provides a sensitive and inexpensive method for investigating patients in whom opportunistic esophagitis is suspected and for monitoring their response to therapy. 相似文献
999.
Warren C. Bogard Jr. Richard T. Dean Yashwant Deo Renato Fuchs Jeffrey A. Mattis Arlene A. McLean Harvey J. Berger 《Seminars in nuclear medicine》1989,19(3):202-220
Issues associated with the large-scale production of monoclonal antibodies for pharmaceutical applications are examined. The development of a commercial monoclonal antibody production process involves much more than just scaling-up the laboratory process and making it cost-effective. It involves establishing the hybridoma cell bank with cells that are free of adventitious agents such as viruses and mycoplasma, that have stability in continuous culture for antibody-production rate and cell viability, and that do not have unusual or expensive media requirements. The style and mode of operation of the bioreactor used to produce the antibody must be explored. The antibody-based product must be processed to high levels of purity, and specific contaminants such as DNA and endotoxin must be reduced to extremely low levels. Appropriate labeling or drug conjugation chemistries must also be developed. The product must be formulated so that it has performance characteristics that are stable over a reasonable period of time. Adequate test procedures must be developed to assure product purity, activity, stability, and safety on a lot-to-lot-basis. Compliance with federal regulations, guidelines, and procedures must be guaranteed. In the coming decade, it is likely that the two arms of biotechnology, hybridoma technology and recombinant DNA technology, will be used together to generate unique protein molecules. These new reagents will face the same practical considerations summarized in this review. 相似文献
1000.
Prophylactic closed suction drainage has been advocated in a variety of surgical wounds, but its use in wounds involving vascular anastomoses has not been studied. Fifty patients undergoing lower extremity revascularization that required bilateral groin incisions were randomly assigned to have either the right or left side of the groin drained with a closed suction catheter. The contralateral wound was closed without drainage. Statistically there was no difference between wound closed with drains and undrained wounds in the occurrence of hematomas, seromas, lymphoceles, superficial infections, subcutaneous infections, or graft infections; although serious complications were more frequent in the drained wounds. Prophylactic closed suction drainage appears to offer no advantage over closure without drainage in wounds of the groin resulting from elective vascular operations. 相似文献