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1.
BACKGROUND AND PURPOSE: Although indomethacin has been demonstrated to prevent germinal matrix and intraventricular hemorrhage in clinical and animal studies, the mechanism of action of this agent to prevent hemorrhage remains unclear. Previous studies have demonstrated both that the microvessels in the germinal matrix of newborn beagle pups undergo basement membrane maturation during the first 4 postnatal days and that indomethacin may promote laminin deposition in tumor cell culture systems. METHODS: We employed the newborn beagle pup model to test the hypothesis that indomethacin may stimulate laminin deposition in germinal matrix microvessels. Newborn pups were randomized to receive either 0.1 mg/kg/dose i.p. indomethacin or an equal volume of saline diluent. Pups received doses of study medication once a day for 1, 2, or 3 days and were studied on postnatal days 1, 2, 3, or 4. Pups were anesthetized and systemically perfused with buffered formalin; the brains were removed and prepared for immunohistochemical study. RESULTS: Sections stained with Bandeiraea lectin demonstrated that there was no difference in germinal matrix vessel density among the postnatal ages studied; similarly, there were no differences in vessel density between saline- and indomethacin-treated animals at any postnatal age. Quantification of germinal matrix stained intensity by confocal microscopy demonstrated significant increases in indomethacin-treated pups for both laminin staining at postnatal days 2 (p = 0.05) and 3 (p = 0.0009) and type V collagen staining at postnatal day 2 (p = 0.011). Although staining for beta 1 integrins increased across postnatal ages, there were no differences between saline- and indomethacin-treated animals. CONCLUSIONS: These data suggest that indomethacin may stimulate basement membrane deposition in the germinal matrix microvessels of newborn beagle pups to prevent germinal matrix and/or intraventricular hemorrhage.  相似文献   
2.
酞丁安对映体合成及其抗单纯疱疹病毒活性评价   总被引:1,自引:0,他引:1  
酞丁安(3-酞酰亚胺-2-氧-正丁醛双缩氨硫脲,TDA)是药物研究所创制的抗病毒新药。为了研究其对映异构体(R),(S)-TDA对病毒活性及毒性是否有差异,并与消旋酞丁安(RS)-TDA的抗病毒活性及毒性进行比较,本文分别用已知构型的(R)-与(S)-丙氨酸为原料,通过缩合等6步反应,得到光学活性的(R)-,(S)-TDA,并与外消旋酞丁安比较其抗病毒活性及毒性。三者的抗单纯疱疹病毒活性与对细胞的毒性差别不大,说明消旋酞丁安临床使用是安全有效的。  相似文献   
3.
Cystic lesions of the thyroid are common findings. Although many thyroid cysts are of benign, some cases of hemorrhagic degenerative changes occur in neoplastic nodules, mostly follicular neoplasms and papillary carcinomas. The occurrence of hemorrhagic changes in medullary carcinomas has never been documented with aspirative cytological and histological pictures to the best of our knowledge. A case of medullary thyroid carcinoma with a large central hemorrhagic cyst is described, and the literature regarding the pathogenesis of this regression and the occurrence of cystic neoplasms in the thyroid is reviewed.  相似文献   
4.
We evaluated the efficacy of a PCR-reverse cross-blot hybridization assay, a test which permits identification of mycobacteria by means of species-specific probes and a Mycobacterium-specific probe, for early detection of negative BACTEC MGIT 960 mycobacterial cultures. Aliquots of 549 cultures were collected 7 days after the culture media were inoculated with various clinical specimens and tested with the molecular assay. PCR results were compared to those obtained at the end times with the BACTEC MGIT 960 system. Of the 549 specimens analyzed, 484 were found to be negative and 64 were found positive by both methods; one specimen, found to be positive by the BACTEC MGIT 960 system, was identified as negative by the molecular assay. In view of its high negative predictive value (99.8%), the PCR-reverse cross-blot hybridization assay appears to be a valid tool for early detection of negative BACTEC MGIT 960 cultures.  相似文献   
5.
This study was carried out to evaluate the rate of recovery and time required for detection of mycobacteria from pulmonary and extrapulmonary human clinical samples, by using a fluorescence-quenching-based oxygen sensor (BACTEC 9000 MB; Becton Dickinson Microbiology Systems, Sparks, Md.). The results were compared with those obtained by microscopy, conventional culture in Lowenstein-Jensen (LJ) medium, and a BACTEC radiometric system (BACTEC 460 TB; Becton Dickinson). Of the 779 clinical samples processed, 364 from pulmonary sites and 415 from extrapulmonary sites, 62 (7.9%) were positive for mycobacterial isolates; of the positive samples, 59 (95.1%) were detected with the fluorescent BACTEC 9000 MB system, 57 (91.9%) were detected with the radiometric system (BACTEC 460 TB), and 43 (69.3%) were detected with LJ conventional culture. The mean times to detection of all mycobacteria with BACTEC 9000 MB and BACTEC 460 TB were similar (10.3 and 10.0 days, respectively). The results obtained indicate that the nonradiometric BACTEC (BACTEC 9000 MB) system is as efficient as Bactec 460 TB and significantly more efficient than LJ for the rapid recovery of mycobacteria from both pulmonary and extrapulmonary clinical specimens. Though the BACTEC 9000 MB system is recommended for respiratory specimens, we demonstrated that it can be successfully used also for recovery of mycobacteria from clinical specimens from various extrapulmonary sites.  相似文献   
6.
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
7.
李陕区  闫小君 《医学争鸣》2000,21(7):F002-F002
0 引言 转化生长因子 β1(TGFβ1)可抑制肝细胞增生 ,抑制肝细胞生长因子 (HGF)对肝细胞有丝分裂的促进作用 .肝炎患者肝组织中 TGFβ1和 HGF的 m RNA表达明显增加 ,它能表达乙型肝炎病毒 (HBV) X基因 (HBX)的转基因小鼠中HBX基因可激活 TGFβ1基因的转录 [1 ,2 ] .我们对急慢性乙型肝炎和肝硬化患者血清进行 TGFβ1和 HBX蛋白测定 ,并研究它们的变化及意义 .1 对象和方法1.1 对象 急性乙型肝炎 (AHB)患者 19(男 13,女 6 )例 ,年龄 18~ 45岁 ;慢性乙型肝炎患者 2 2 (男 15 ,女 7)例 ,年龄 2 2~48岁 ;肝硬化 (L C) 2 …  相似文献   
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A molecular analysis of drug-resistant isolates of Mycobacterium tuberculosis was done in a population with a high prevalence of human immunodeficiency virus infection. Seventy-one consecutive isolates were tested for genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol by polymerase chain reaction-single strand conformation polymorphism analysis and automated sequencing of target regions. Phenotypic and genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol were detected in 23.4%, 11.2%, 7%, and 5.6% of isolates and in 87%, 88%, 40%, and 100% of resistant isolates, respectively. Specificity was 100% for all target regions. When rpoB, katG, and ahpC mutation analysis were combined, 86% of resistant isolates to any drug were identified. No mutations in inhA were found in isoniazid-resistant isolates. Molecular detection of drug resistance, particularly for isoniazid and rifampicin, may represent a sensitive and very specific technique. The strategy of selecting rpoB, katG, and ahpC to quickly identify most resistant isolates, with a relevant saving of resources, is warranted.  相似文献   
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