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1.
The purpose of this study was to evaluate the effects of pegfilgrastim, a long-acting granulocyte colony-stimulating factor, on the normal biodistribution of (18)F-FDG in an animal model and in humans. METHODS: Two groups of 12 rats received a single subcutaneous injection of either normal saline or pegfilgrastim. One, 7, 14, and 21 d after injection, biodistribution studies were performed 1 h after (18)F-FDG injection. Sixteen breast cancer patients underwent baseline (18)F-FDG PET/CT and, approximately 1 wk after receiving 1 dose of docetaxel and adjunctive pegfilgrastim, follow-up (18)F-FDG PET/CT (scan 2). Standardized uptake values corrected for lean body mass (SUL) were determined for several normal organs before and after therapy. RESULTS: In rats, bone marrow (18)F-FDG uptake (standardized uptake value) was higher in the pegfilgrastim group 1 d after injection (mean +/- SD, 8.3 +/- 4.1 vs. 2.5 +/- 0.2, P < 0.05), whereas (18)F-FDG uptake in blood was lower (0.41 +/- 0.06 vs. 0.49 +/- 0.01, P < 0.05). In patients, mean SUL was higher in bone marrow (4.49 +/- 1.50 vs. 1.33 +/- 0.22, P < 0.0001), spleen (3.29 +/- 0.83 vs. 1.23 +/- 0.23, P < 0.0001), and liver (1.45 +/- 0.25 vs. 1.31 +/- 0.23, P = 0.01) but lower in brain (4.18 +/- 0.76 vs. 5.14 +/- 1.44, P < 0.01) on scan 2 than on the baseline scan. CONCLUSION: In both the animal model and humans, pegfilgrastim markedly increased bone marrow uptake of (18)F-FDG and reduced (18)F-FDG uptake in some normal tissues. These profound alterations in (18)F-FDG biodistribution induced by pegfilgrastim must be considered when one is evaluating quantitative (18)F-FDG PET scans for tumor response to therapy.  相似文献   
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Antigenic characterization of urothelial cells cultured from normal adult ureter was performed. These cells were cultured using a simplified isolation and culture technique and a commercially available serum-free medium. The cells growing in these cultures had epithelioid morphology and normal quantities of DNA. The antigen expression on these cultured normal urothelial cells was evaluated using a panel of monoclonal antibodies: 5G6.4, AN43, URO-5, anti-keratin and anti-blood group antibodies, and 425 (anti-epidermal growth factor receptor). Lower levels of anti-A and AN43 binding on cultured cells were observed than are seen on urothelial cells in sections of normal ureter, while the binding of anti-blood group H, 5G6.4, and URO-5 was unchanged. Binding of anti-epidermal growth factor receptor antibody 425 was improved if the cells were grown in medium lacking epidermal growth factor. These results confirm the urothelial origin of these cultured urothelial cells but indicate that some antigenic differences between cultured normal urothelial cells and urothelial cells in situ in the normal ureter exist.  相似文献   
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As natural rubber latex (latex) has become more widespread in our environment, physicians have become increasingly aware of the problem of possible allergic reactions. Many fatal and near-fatal incidents have been reported (mainly during surgery) (1—3) and data has been published on groups frequently exposed to latex, such as patients with spina bifida (4—9), healthcare professionals (10—12) and occupationally exposed persons (13). The incidence of latex allergy in children seems to be increasing (14). Tests are therefore needed which can reliably detect sensitization to latex. Our aim was to compare the diagnostic accuracy of three commercial immunoassays for measuring specific IgE in serum to latex.  相似文献   
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Modulation of spinal systems activated by N-methyl-D-aspartate (NMDA) and substance P administered IT have been an area of interest in several laboratories. In the present investigations, behavior induced by the excitatory amino acid kainic acid, but not quisqualate, is demonstrated to be modulated in a manner similar to that previously observed for NMDA. Biting, scratching and licking behavior was induced by IT injections of excitatory amino acids or substance P in mice. Behavior induced by kainic acid (IT) injection was inhibited in a dose-dependent manner by coadministration of morphine (ICV), norepinephrine (IT), N-ethyl carboxamidoadenosine (NECA) (IT) and agonists interacting at PCP receptors (IT). Kainic acid and NMDA differed, however, in that a dopaminergic agonist, apomorphine, inhibited kainic acid-, but not NMDA-induced behavior and a selective NMDA receptor antagonist inhibits NMDA-, but not kainic acid-induced behavior. Behavior induced by quisqualate (IT) was not inhibited by any treatment and may have nonspecific actions in this type of assay. Our observations support independent spinal sites of action for behavior induced by kainic acid and NMDA, but several similarities were observed in the modulation of spinal systems activated by these agents.  相似文献   
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T B?ttger  S St?rkel  M St?ckle  W Wahl  A Heintz  M Jugenheimer  O Effenberger-Kim  T Vinh  T Junginger 《Der Chirurg》1991,62(6):467-72; discussion 472-3
Esophagus cancer is a heterogeneous disease with considerable differences in malignant behaviour. Some relevant factors for prognosis are known. In this study we analyzed DNA-ploidy as a potential prognostic parameter in esophagus carcinoma. Paraffin embedded histological material from 50 patients with an esophagus cancer, obtained by resection, were selected for analysis. Tumor areas within the paraffin material were identified by HE-stained reference sections. One 50 microns section was dewaxed, rehydrated and mechanically and enzymatically treated to a suspension of 10,000 cells/ml. 1 ml of the suspension, containing bare nuclei with small rests of cytoplasma was centrifuged on glass slides. The fixed nuclei were air-dried and stained by Feulgen-SITS technique, which allows quantitative measurement of DNA. The DNA analysis was carried out with a computer-controlled single cell cytophotometry (Leytas 2, Leitz, Wetzlar). In contrast to the flow cytometry with image cytometry only tumors cells were measured. Overlapping nuclei, dirt and other artefacts as well as inflammatory cells were efficiently eliminated. With the DNA image cytometry we could differentiate between diploid and hypotriploid, hypertriploid aneuploid tumors. Best prognosis had diploid and hypotriploid tumors, the worst hypertriploid carcinomas. In the multivariate analysis the DNA-content of the tumor cells in esophagus cancer was the only prognostic parameter. DNA-content of tumor cells may become considerably clinical relevant in esophagus cancer for the decision to perform a resection or palliative treatment. In patients with hypertriploid tumors an adjuvant oncological therapy may increase the prognosis.  相似文献   
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We performed a prospective, double-masked, placebo-controlled, six-period, cross-over study in which normal subjects were randomly assigned to treatment and compared three different formulations of apraclonidine hydrochloride (the present commercially available formulation, and formulations with hydroxypropylmethylcellulose or lysolecithin). We also evaluated the efficacy of a 16-microliters and 30-microliters drop size. The magnitude and duration of decrease in intraocular pressure was comparable for all formulations. Most subjects tolerated all formulations well with only a few reporting any side effects. The best-tolerated formulation was 0.5% apraclonidine hydrochloride delivered with a 16-microliters drop size. Dry mouth developed frequently with the commercially available 1% apraclonidine solution. Blurred vision complicated the use of the formulation containing hydroxypropylmethylcellulose. Both dry mouth (P less than .05) and blurred vision (P = .004) were statistically significant side effects.  相似文献   
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