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141.
Y Zhang HP Hetherington EM Stokely GF Mason DB Twieg 《Canadian Metallurgical Quarterly》1998,39(6):999-1004
OBJECTIVE: To report our experience with erosion of permanent suture or mesh material after abdominal sacrocolpopexy. METHODS: A retrospective chart review was performed to identify patients who underwent sacrocolpopexy by the same surgeon over 8 years. Demographic data, operative notes, hospital records, and office charts were reviewed after sacrocolpopexy. Patients with erosion of either suture or mesh were treated initially with conservative therapy followed by surgical intervention as required. RESULTS: Fifty-seven patients underwent sacrocolpopexy using synthetic mesh during the study period. The mean (range) postoperative follow-up was 19.9 (1.3-50) months. Seven patients (12%) had erosions after abdominal sacrocolpopexy with two suture erosions and five mesh erosions. Patients with suture erosion were asymptomatic compared with patients with mesh erosion, who presented with vaginal bleeding or discharge. The mean (+/-standard deviation) time to erosion was 14.0+/-7.7 (range 4-24) months. Both patients with suture erosion were treated conservatively with estrogen cream. All five patients with mesh erosion required transvaginal removal of the mesh. CONCLUSION: Mesh erosion can follow abdominal sacrocolpopexy over a long time, and usually presents as vaginal bleeding or discharge. Although patients with suture erosion can be managed successfully with conservative treatment, patients with mesh erosion require surgical intervention. Transvaginal removal of the mesh with vaginal advancement appears to be an effective treatment in patients failing conservative management. 相似文献
142.
E Elstner M Linker-Israeli J Le T Umiel P Michl JW Said L Binderup JC Reed HP Koeffler 《Canadian Metallurgical Quarterly》1997,99(2):349-360
Patients with acute promyelocytic leukemia (APL) usually relapse after all-trans retinoic acid (RA) treatment because this therapy fails to eradicate the malignant clone. Our data showed that KH 1060 and other 20-epi vitamin D3 analogs alone were potent inhibitors of clonal growth of NB4 cells, an APL cell line (ED50, approximately 5 x 10(-11) M). The combination of KH 1060 and 9-cis-RA synergistically and irreversibly enhanced this effect. Neither KH 1060 nor 9-cis-RA (10(-6) M, 3 d) were strong inducers of differentiation of NB4 cells. However, 98% of the cells underwent differentiation to a mature phenotype with features of both granulocytes and monocytes after exposure to a combination of both compounds. Apoptosis only increased after incubation of NB4 cells with 9-cis-RA alone (28%) or with a combination of 9-cis-RA plus KH1060 (32%). Immunohistochemistry showed that the bcl-2 protein decreased from nearly 100% of the wild-type NB4 cells to 2% after incubation with a combination of KH 1060 and 9-cis-RA, and the bax protein increased from 50% of wild-type NB4 cells to 92% after culture with both analogs (5 x 10(-7) M, 3 d). Western blot analysis paralleled these results. Studies of APL cells from one untreated individual paralleled our results with NB4 cells. Taken together, the data demonstrated that nearly all of the NB4 cells can be irreversibly induced to differentiate terminally when exposed to the combination of KH 1060 and 9-cis-RA. 相似文献
143.
概述了美国几种较成熟的热煤气脱硫吸附剂的配方、制备技术及吸附剂在若干试验条件下强度、活性、寿命等宏观特性的测试结果。 相似文献
144.
DP Berry KG Harding MR Stanton B Jasani HP Ehrlich 《Canadian Metallurgical Quarterly》1998,102(1):124-31; discussion 132-4
The closure of ungrafted sacrococcygeal pilonidal sinus excisional wounds was studied in 15 patients. Wound punch biopsies were taken on a regular basis, and histologic sections were made. To document changes, computer-assisted morphometric image analysis was employed. Initial average wound depth was 37.8 +/- 4.6 mm, and complete closure (0 wound depth) was reached by 68 days. Wound contraction contributed 88 percent to wound closure, whereas the deposition of scar only contributed 12 percent. Maximum cells density within granulation tissue was reached by day 18. Myofibroblasts, identified by alpha-smooth muscle actin immunostaining, first appeared on day 11. Unlike those observed in laboratory animals, myofibroblasts were a minor cell population of granulation tissue, never exceeding 10 percent of the cells. The pattern of collagen fiber organization was documented by polarized light microscopy of Sirius red-stained sections. Early granulation tissue collagen fibers demonstrated a fine greenish birefringence, whereas more mature granulation tissue collagen fibers were thicker, displaying orange-yellowish birefringence. Myofibroblasts were associated exclusively with thicker collagen fibers, whereas fibroblasts were associated with both fine and thick collagen fibers. It is proposed that human wound contraction involves a volume change whereby normal dermal and adipose tissues are pulled into the defect by forces generated within fibroblasts. 相似文献
145.
Q Wang S Zhong J Ouyang L Jiang Z Zhang Y Xie S Luo 《Canadian Metallurgical Quarterly》1998,(348):259-268
Culture selected and expanded osteoblastic cells may be able to be reintroduced into massive skeletal defects to accelerate cell mediated regeneration of skeletal tissues, especially in bone ingrowth in total joint replacement, fracture healing, and osteoporosis. In vitro osteogenic cell culture is a useful model in studying the mechanism of bone metabolism under direct current stimulation. In this study, an osteoblastlike cell line was isolated from newborn rat calvaria. The osteogenic processes of the in vitro cultured cell line were studied by cytochemical, electron microscopic, and energy dispersive x-ray analysis techniques that resembled those observed in membrane bone ossification centers in vivo. Direct current stimulation of 100 microA/cm2 accelerated greatly the proliferation and calcification of the in vitro cultured cells. Intracellular free calcium ion metabolism was measured with an Adherent Cell Analysis and Sorting Machine. Under direct current stimulation, intracellular free calcium ion concentration increased an average of 2.3 times of the original level, which may play a key role in regulating osteogenesis and bone metabolism. 相似文献
146.
根据冲天炉的冶金还原反应原理,在炉后加入廉价的硼矿石,代替昂贵的硼铁合金生产气缸套,取得显著的经济效益。 相似文献
147.
Immunological identification of candidate proteins involved in regulating active shape changes of outer hair cells 总被引:1,自引:0,他引:1
M Knipper U Zimmermann I K?pschall K Rohbock S Jüngling HP Zenner 《Canadian Metallurgical Quarterly》1995,86(1-2):100-110
By employing immunological methods, it has been demonstrated that myosin, myosin light chain (MLC) and myosin light chain kinase (MLCK) proteins in outer hair cells (OHC) are immunologically different from isoforms in platelets, smooth muscle and heart muscle, and are probably more related to isoforms found in red blood cells (RBC). Moreover, proteins related to band 3 protein (b3p) and protein 4.1 (p 4.1), ankyrin as well as fodrin and spectrin, but not glycophorin, have been identified in isolated OHCs. Both OHCs and RBC differ from other motile non-muscle cells in their lack of smooth muscle isoforms of actin, their common high levels of spectrin-, ankyrin- and band 3-like proteins, as well as the expression of the 80 kDa protein 4.1 isoform. The data support the notion that motility of OHC may be based upon regulation of the b3p/p 4.1/ankyrin complex, and thus may be reminiscent to the active shape changes in RBC. 相似文献
148.
Coating of Silicon Nitride and its Colloidal Behavior 总被引:2,自引:0,他引:2
Qiang Tang Zhipeng Xie Jinglong Yang Yong Huang 《Journal of Materials Science Letters》1998,17(14):1239-1241
149.
150.
研究了温度及气体压力对漂移室(工作于正比区)气体放大倍数的影响,温度和气体压力的变化范围分别是5 ̄40℃及90 ̄105kPa。用实验数据拟合得到了函数关系并测量了几种饱和度下函数中的参数值。 相似文献