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11.
自Messerldinger 1972年开始采用鼻内镜手术治疗慢性鼻窦炎至今已近40年[1],在我国也已经有20年的历史.1995年Kennedy将其命名为功能性内镜鼻窦手术(functional endoscopic sinus surgery,FESS)[2].时至今日,FESS仍然是慢性鼻窦炎最重要的治疗手段之一. 相似文献
12.
Transforming growth factor beta effects on expression of G1 cyclins and cyclin-dependent protein kinases. 总被引:18,自引:7,他引:11 下载免费PDF全文
Y Geng R A Weinberg 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(21):10315-10319
Transforming growth factor beta 1 (TGF-beta 1) is a potent growth-inhibitory polypeptide. The mechanism of TGF-beta 1 inhibition has been related to its ability to prevent the hyperphosphorylation of retinoblastoma protein (pRb). Several lines of evidence have suggested that cell cycle-regulated protein kinases are responsible for the hyperphosphorylation of pRb. We demonstrate here that TGF-beta 1 has profound effects on the expression of genes encoding certain G1 cyclins and their associated kinases, which provides one explanation of TGF-beta 1 effects on pRb hyperphosphorylation. These results also suggest that the growth-inhibitory effects of TGF-beta 1 in many cells are attributable to its effects on the cell cycle apparatus involved in programming G1 transit. 相似文献
13.
Multiple-bandwidth photoacoustic tomography 总被引:3,自引:0,他引:3
Photoacoustic tomography, also referred to as optoacoustic tomography, employs short laser pulses to generate ultrasonic waves in biological tissues. The reconstructed images can be characterized by the convolution of the structure of samples, the laser pulse and the impulse response of the ultrasonic transducer used for detection. Although the laser-induced ultrasonic waves cover a wide spectral range, a single transducer can receive only part of the spectrum because of its limited bandwidth. To systematically analyse this problem, we constructed a photoacoustic tomographic system that uses multiple ultrasonic transducers simultaneously, each at a different central frequency. The photoacoustic images associated with the different transducers were compared and analysed. The system was tested by imaging both mouse brains and phantom samples. The vascular vessels in the brain were revealed by all of the transducers, but the image resolutions differed. The higher frequency detectors provided better image resolution while the lower frequency detectors delineated the major structural traits with a higher signal-noise ratio. 相似文献
14.
Iwasaki M Kobayashi K Suzuki H Anan K Ohno S Geng Z Li G Inoko H 《Tissue antigens》2000,56(2):136-142
Genetic polymorphism in the ABO blood group gene of Han, Kazak and Uygur populations inhabiting the most northwestern part of China was investigated using polymerase chain reaction-based techniques. The present study enrolled 43 healthy unrelated Han, 37 Kazak and 59 Uygur volunteers. The allele in A1 blood group is distinguished A0101 and A0102 in difference of nucleotide position 467. The A0101 allele is more frequent in Caucasian and the A0102 allele is characteristic in Mongoloid. It must be notable that A0201 in the A2 group (with a single base deletion at nucleotides 1059 to 1061) which was characteristic of Caucasian was observed in Kazak and Uygur populations but not in Han. Further, 00201 (with no nucleotide deletion at 261 and three nucleotide differences), which is frequent in different races including Caucasian except for Mongoloid, was detected also in Kazak and Uygur populations. The frequencies of B0101 in Kazak, Uygur and Han were comparable to those of other Asian populations but higher than those of Caucasian populations. Collectively, these results reveal that the allele frequencies of Kazak and Uygur at the ABO blood group locus are an intermediate between those of Mongoloid and Caucasian, suggesting the admixed feature of Kazak and Uygur with Mongoloid and Caucasian. 相似文献
15.
肝尾状叶的外科解剖及其临床应用 总被引:1,自引:0,他引:1
在42例成人肝脏标本上,研究了肝尾状叶的形态,动脉、静脉和肝管的分布特征;尾状叶常有3个突起,即尾状突、乳头突和下腔静脉后突,且变异较大;尾状叶有两个恒定的蒂,其结构排列由浅入深分别是门静脉支、肝动脉支和肝管。尾状叶静脉有2~5支,其中以3支居多,主要汇入下腔静脉肝后段的中、下1/3部的左前壁。中结合解剖学研究总结了施行肝尾状叶肿瘤切除术的方法和经验。 相似文献
16.
心钠素免疫反应在豚鼠耳蜗中的整体分布 总被引:9,自引:0,他引:9
目的 :研究豚鼠耳蜗中心钠素 (ANP)免疫反应的分布状态 ,为探讨ANP在耳蜗中的作用提供形态学基础。方法 :采用免疫组织化学ABC法检测ANP在正常豚鼠耳蜗各组织中的分布特征。结果 :在耳蜗 1~ 4回的血管纹、螺旋缘、Corti’s器、螺旋神经节和中间阶外壁的螺旋韧带均发现有ANP反应 (ANP IR)阳性产物 ;而耳蜗骨壁、前庭膜、鼓阶外壁的螺旋韧带和鼓阶的下壁ANP IR为阴性。结论 :耳蜗中的ANP在内耳淋巴液的生成和声信号的传导以及耳蜗血流量的调节等方面可能担负着重要的作用 相似文献
17.
γδ cells are attractive candidates for mediators of autoimmune disease. They can expand in germ-free mice, probably through recognition of autoantigens, and γδ-cell-deficient mice, unlike mice deficient in αβ T cells or B cells, show no severe defects in the immune response to foreign antigen challenge. A capacity of γδ cells to effect or regulate tissue damage is also plausible, given their ready localization to tissues, and their myriad of effector functions. Added to this, attempts to reconstruct the physiological course of autoimmune diseases with only autoreactive αβ T cells seem invariably to fall short for lack of other unidentified players. γδ cells and their putative ligands have been linked to autoimmune conditions, and recent experiments confirm that γδ cells play a significant role in autoimmune disease in vivo. 相似文献
18.
急性上颌窦炎实验动物模型的建立 总被引:1,自引:1,他引:1
目的:拟建立急性上颌窦炎的实验动物模型,并探讨窦口的阻塞和致病菌的毒力在急性上颌窦炎的发病机制中的地位。方法:第一天,阻塞单侧窦口,对侧做假手术。次日,注入0.5ml108CFU/ml肺炎链球菌悬浮液。第五天处死动物、观察、分离培养细胞、取材和制作切片。结果:阻塞上颌窦口和注入肺炎链球菌的联合组,鼻部症状明显;进食量减少;鼻窦粘膜水肿、微红,具有较多脓性分泌物,微血管扩张,白细胞浸润;肺炎链球菌的重新分离培养率为100%(与其余组比较具有显著意义P<0.01)。而仅阻塞上颌窦口或仅注入肺炎链球菌或假手术均无明显临床症状及组织病理学改变,细胞培养率也低。结论:窦口的阻塞和致病菌的毒力是上颌窦炎发生发展的重要的条件,其中,窦口的阻塞起着关键性作用;联合阻塞窦口并注入有荚膜的肺炎链球菌能较理想地建立急性上颌窦炎实验动物模型。 相似文献
19.
Shuo Dong Jie-Ping Geng Jia-Hua Tong Yu Wu Jin-Ren Cai Guan-Lin Sun Shu-Rong Chen Zhen-Yi Wang Christian-Jacques Larsen Roland Berger Sai-Juan Chen Zhu Chen 《Genes, chromosomes & cancer》1993,6(3):133-139
DNA studies of the translocation t(15;17) in acute promyelocytic leukemia (APL) have shown that the retinoic acid receptor alpha (RARA) gene on chromosome 17 is juxtaposed to the promyelocytic leukemia (PML) gene on chromosome 15. The PML breakpoints have been mapped to 3 clusters: bcr1, bcr2, and bcr3. We have examined the PML breakpoint distribution in a series of 33 Chinese patients with APL Twenty-two patients fell within bcr1, 2 within bcr2, and 9 within bcr3. The primary structure of the reciprocal chromosome translocation joints of one patient and that of their normal counterparts have been determined and compared to those of 2 previously reported cases. These studies revealed possible topoisomerase II cleavage sites close to the breakpoints and suggested implications of DNA attachment sites to nuclear matrix. We propose that these features are relevant to the process of illegitimate recombination generating the translocation. © 1993 Wiley-Liss, Inc. 相似文献
20.
作者探讨了鸡蛋过敏特应性皮炎(AD)患儿外周血单个核细胞(PBMCs)对卵白蛋白(OA)刺激的增殖反应并观察了酮替酚(KF)对此反应的影响.结果提示AD患儿的PBMCs增殖反应显著高于健康儿童;KF可剂量依赖性地抑制鸡蛋过敏AD患儿PBMCs对OA刺激的增殖反应,且这一效应可通过KF抑制T细胞的作用而得以实现.KF对植物血凝素(PHA)和破伤风类毒素(TT)诱导的PBMCs增殖反应无抑制作用.这说明KF只抑制食物过敏AD患者PBMCs对食物抗原的特异性增殖反应. 相似文献