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排序方式: 共有993条查询结果,搜索用时 15 毫秒
31.
目的利用4种不同支架材料构建复合式口腔黏膜,并比较其组织结构特点。方法体外培养人口腔黏膜的成纤维细胞和角质形成细胞,在4种支架材料中加入成纤维细胞,培养7d后,在支架表面加入角质形成细胞,培养4d后,移至气-液界面继续培养7d。苏木精-伊红染色镜下观察构建的复合式口腔黏膜的组织形态学特点。结果 4种支架均可构建形成复层上皮。其中,上皮层与脱细胞真皮基质材料(de-epidermised dermis,DED)结合紧密,形成的人工黏膜有明显的上皮钉突。不同于以往报道,上皮层与Alloderm结合并不十分紧密。以胶原凝胶为基质形成的人工口腔黏膜最厚,有明显分层。以胶原海绵-胶原凝胶为基质形成的复层上皮在部分区域长入至胶原海绵的空隙中。结论以DED和胶原凝胶为支架构建的口腔黏膜更接近于天然结构,而后者脆性较大,限制了其临床应用的可能。 相似文献
32.
肠息肉发生的细胞和分子生物学研究进展 总被引:1,自引:0,他引:1
肠息肉是一类从黏膜表面突出到肠腔内的隆起状病变的临床诊断.在最近的研究中陆续证实,其发生和发展的原因和机制,是由于Bmprla,APC,SMAD4,PTEN,STK11等基强突变而使各种细胞信号分子通过影响BMP信号通路,PTEN信号通路及Wnt信号通路所组成的生长信号调控网络,造成β-catenin在肠干细胞中的过度积聚,使得肠干细胞功能紊乱,导致其自我更新、克隆增殖、分化和凋亡失去平衡的结果. 相似文献
33.
34.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
35.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
36.
37.
Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
38.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions. 相似文献
39.
Occlusion of varicoceles wih detachable balloons 总被引:1,自引:0,他引:1
40.
J. William Charboneau R. R. Hattery B. Williamson L. H. Weiland D. M. Barrett 《Urologic radiology》1981,2(1):89-93
Malacoplakia is a distinct pathologic lesion usually involving the urinary bladder. The lesions consist of smooth, yellowish brown plaques in the mucosa varying from 0.1 to 0.3 cm in diameter. The lesion was first described by Michaelis and Gutmann in 1902, and was subsequently named malacoplakia (“soft plaque”) by von Hansemann in 1903. This report describes a case of renal parenchymal malacoplakia presenting on excretory urography as a cystic renal mass associated with malacoplakia involving the ureter and bladder. The usual urographic differential diagnoses of a cystic renal mass include cystic renal cell carcinoma, mutilocular cyst, benign cystic nephroma, hemorrhagic cyst, hematoma, and renal abscess. In patients, especially females, with a renal mass associated with a history of repeated urinary tract infections, altered immune syndromes, abnormal cystoscopic findings, or filling defects in the collecting system or urter, renal parenchymal malacoplakia should be included in the differential diagnosis. 相似文献