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41.
目的介绍一种埋线法固定眉,结合重睑成形术治疗中青年上睑皮肤松弛的手术方案。方法应用3-0无损伤线皮内缝合,固定眉于眉骨骨膜上,再结合重睑成形术,去除上睑多余的皮肤,共治疗29例上睑皮肤松弛的患者。结果本组29例患者,术后Ⅰ期愈合。21例患者术后随访6个月至2年,均获得满意效果,上睑明显年轻化,无并发症。结论重睑成形术结合眉埋线固定法治疗上睑皮肤松弛,是一种简单有效的上睑年轻化治疗方案。 相似文献
42.
目的探讨^188Re—Herceptin-磁性纳米微粒在外置磁场下对HER-2/neu癌基因高表达的SKBR-3乳腺癌细胞的靶向结合性及抗癌作用。方法采用戊二醛交联法使人源性单克隆抗体Her—ceptin与磁性纳米微粒交联,用直接标记法制备^188Re—Herceptin及^188Re—Herceptin-磁性纳米微粒,用羰基铼标记法制备^188Re-磁性纳米微粒。肿瘤细胞体外抑制实验设4个组:^188Re—Herceptin-磁性纳米微粒组、^188Re—Herceptin组、^188Re-磁性纳米微粒组和^188ReO4^-组,各组均设3.7×10^4、18.5×10^4、37×10^4、55.5×10^4、74×10^4Bq/ml5个放射性剂量级别;另设生理盐水对照组。采用四甲基偶氮唑蓝(MTT)法测定各组的抑瘤效应,计算相对抑制率,采用半数抑制放射性浓度(IC50)对各组抑瘤作用进行比较和评价。结果^188Re—Herceptin-磁性纳米微粒和^188Re—Herceptin组对SKBR-3细胞均有较强杀伤作用,且呈剂量依赖性;而^188Re-磁性纳米微粒和^188Re04组的杀伤作用较弱0188Re—Herceptin-磁性纳米微粒组的IC50(53.1×10^4Bq/L)明显低于^188Re—Herceptin组(76.1×10^4Bq/L);^188Re一磁性纳米微粒组和^188ReO4组的IC50分别为169×10^4和175×10^4Bq/L,明显高于前2组。结论^188Re—Herceptin-磁性纳米微粒和^188Re—Herceptin均可明显抑制体外培养的SKBR-3乳腺癌细胞增殖,且前者的抑制作用较后者强。 相似文献
43.
Richard Werner Karsten Alfke Tobias Schaeffter Arya Nabavi H Maximilian Mehdorn Olav Jansen 《Magnetic resonance in medicine》2004,52(6):1443-1447
A new method for the selective spin labeling of left- or right-sided supplying arteries of the brain without the need for additional RF coils is demonstrated. A clinical 1.5 T scanner was used. The spatial selectivity of the labeling process is based on the limited coverage of the excitation field of a standard send/receive head coil together with an oblique positioning of the labeling plane. A computer simulation was used to optimize key labeling parameters under the condition of laminar flow. The validity of the computer model results was confirmed by MRI measurements with a flow model. For human studies, a double-inversion continuous arterial spin labeling (CASL) sequence was modified to allow for arbitrary positioning of the labeling plane. The obtained perfusion-weighted images showed a clear delineation of the perfusion territories of the selected arteries in the anterior circulation of the brain and good gray/white matter contrast. 相似文献
44.
目的改进传统的双环法在乳房缩小术、乳房悬吊术术后外形扁平,凸度不足,上极瘪陷,提升不够等缺点。方法采用双环切口。“扇”形分离、切除皮下部分脂肪,“楔”形切除适量的外上象限腺体,螺旋状旋转剩余腺体成圆锥状,将其固定在第2肋软骨膜上,矫正轻中度乳房肥大和下垂。结果术后随访20例患者1~3个月,乳房上极较丰满,形态好,乳头乳晕功能正常,切口瘢痕轻,乳房肥大和下垂的矫正获得了满意的效果。结论双环切口,螺旋状旋转剩余腺体成圆锥状,并固定于第2肋软骨膜上,可较好地塑形并悬吊乳房,其切口相对隐蔽,术后乳房高凸,上极略饱满,乳头微上翘,乳晕形态合适,是矫正轻中度乳房肥大下垂的一种较理想的术式。 相似文献
45.
上尿路梗阻性急性肾功能不全内、外引流的选择 总被引:1,自引:1,他引:0
目的探讨内、外引流在上尿路梗阻急性肾功能不全时的选择和效果。方法25例各种原因引起的上尿路梗阻(15例肿瘤性梗阻,10例非肿瘤性梗阻)合并急性肾功能不全,分别或先后对12例行输尿管内置双J管(doub le J,D J)内引流15次,对19例行经皮肾穿刺造瘘(percutaneous nephrectomy,PCN)外引流23次。结果引流成功23例,PCN外引流成功率86.9%(20/23),双J管内引流成功率60.0%(9/15),PCN术后继发出血1例。结论对于盆腹腔进展期或广泛转移肿瘤导致的梗阻,PCN解除梗阻优于输尿管支架内引流;非肿瘤性梗阻宜先尝试D J内引流。 相似文献
46.
Magnetically-labeled sensitized splenocytes to identify glioma by MRI: a preliminary study. 总被引:1,自引:0,他引:1
Ali S Arbab Ali M Rad A S M Iskander Kourosh Jafari-Khouzani Stephen L Brown Jamie L Churchman Guangliang Ding Quan Jiang Joseph A Frank Hamid Soltanian-Zadeh Donald J Peck 《Magnetic resonance in medicine》2007,58(3):519-526
This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells. 相似文献
47.
改进的内眦赘皮矫治术联合重睑成形术Ⅰ期成形 总被引:7,自引:2,他引:5
目的 探讨改进的内眦赘皮矫治术联合切开法重睑成形术的方法及临床效果。方法 根据内眦赘皮的轻重程度及方向,采用改良的“Z”成形术,切除或切断内眦部形成赘皮的异位眼轮匝肌及皮下筋膜组织,联合切开法重睑成形术行Ⅰ期成形。结果 本组68例患者,术后赘皮消失,泪阜显露适中,内眦间距缩短,重睑外形美观自然。其中,36例随访3个月至3年,术后皮肤切口无可见瘢痕,形态稳定,内眦赘皮无复发,效果满意。结论 该手术方法能够充分矫正内眦赘皮的异常结构,而与重睑成形术同期施术效果稳定,具有一定的临床应用价值。 相似文献
48.
《Journal of labelled compounds & radiopharmaceuticals》2003,46(13):1241-1247
Tritium was introduced into the new orally active, selective phosphodiesterase type V (PDE V) inhibitor vardenafil (Levitra®), by reduction of a suitable amide precursor with freshly prepared lithium aluminum tritide. A specific activity of 52.7 Ci/mmol (1.95 TBq/mmol) was achieved. In order to overcome the usual technical difficulties during the preparation of complex tritides a new and easy labeling technique which has considerable potential for various tritia‐tion procedures, was developed. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
49.
Hy De Lee Euy Young Soh Hoon Sang Chi Byong Ro Kim Kyong Sik Lee Kyung Soon Song Hyun Joo Jung 《Surgery today》1990,20(2):180-185
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in
relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed
significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02
per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer
patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic
nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis
in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05)
than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without
axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy. 相似文献
50.
The most commonly used photoaffinity labeling probes are compared, which are aryl azides, aryl diazirines, α-diazocarbonyls and benzophenone-derivatives. The compounds were used under identical conditions and crosslinking efficiency, influence of water, irradiation requirements, and by-products were investigated. Using the pentapeptide thymopentin (TP5) as a model system, we synthesized four analogues by solid-phase peptide synthesis and partially N-terminal modification to obtain [p-(3-trifluoromethyl)diazirinophenylalanine5] TP5, [p-benzoylphenylalanine5] TP5, 4-azidobenzoyl-TP5 and 2-diazo-3, 3, 3-trifluoropropionyl-TP5. The peptides were characterized by HPLC and ion-spray mass spectroscopy. Irradiation of the peptides with two different ultraviolet sources was carried out in water, n-propanol and water/n-propanol to imitate both hydrophobic and hydrophilic peptide/protein-interactions as well as the influence of the aqueous environment. Analysis of the products with HPLC, ion-spray MS, HPLC-MS and HPLC-CID-MS revealed that (Tmd)Phe is a highly potent carbene-precursor, which can be transformed easily into uniform crosslinking products by smooth photolysis. However, the electrophilic nature of the intermediate causes a high tendency to react with water molecules. The 4-azidobenzoyl group showed comparable crosslinking efficiency, but the probability to create non-uniform irradiation products (e.g. through rearrangement) is higher, whereas the reaction with water is less dominant. In contrast, Bpa was found to have an extremely low affinity to react with water, whereas prolonged UV irradiation is needed to get complete rearrangement into a variety of products. As the absorption band of α-diazocarbonyls at around 350 nm possesses a low extinction coefficient, 2-diazo-3, 3, 3-trifluoropropionyl-TP5 could not be activated at all with the optimized irradiation conditions that we have chosen for our comparative studies. © Munksgaard 1997. 相似文献