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31.
32.
Objective. To evaluate the results of operative treatment of spinal fracture-dislocation without neumlogic deficits. Metods. Eighteen patients with spinal fracture-dislocation were neurologically intact at the time of injury, and all were treated operatively. The fracture sites were:8 cases in cervical spine, 3 cases in thoracic spine, and 7 cases in lumbar spine. Eight patients with cervical injuries had variant degrees of forward slide and kyphotic deformity. Of the 10 thoracic and lumbar fractures, one had lateral dislocation, 4 cases with kyphotic deformities, 5 cases withspinal canal compromise averaged 50% (ranging from 40% to 70% ).Results. The aveiage period of follow-up was 4.4 years with a range of 11 months to 13 years. All the patients returned to full-time work. No patient developed neurologic deterioration. Kyphotic deformity was corrected in the 4 cases, and no progressive kyphosis was noted. There was no operation-related complication. The averaged post-opera-five hospitalization time was 13 days. Conclusions. Despite the rare incidence of spinal fracture-dislocation without neurologic deficits, we suggested that kind of fracture be considered unstable fracture because of its potential risk of delayed neurologic deterioration and kyphotic deformity, and be treated operatively to restore the sagittal alignment and the stability of the spine.  相似文献   
33.
小鼠颗粒子宫腺细胞的组织学与超微结构的研究   总被引:1,自引:0,他引:1  
对昆明种小鼠颗粒子宫腺细胞(GMG细胞)进行光镜及电镜观察,结果显示:GMG细胞以其胞浆中含耐淀粉酶消化的PAS阳性颗粒为特点,而该种颗粒在电镜下为带有帽状结构的膜包颗粒。GMG细胞有特殊的形态,其出现和消失与妊娠过程同步。  相似文献   
34.
N-端融合蛋白对重组HBeAg抗原性的影响   总被引:1,自引:0,他引:1  
目的 研究 N- 末端融合蛋白对大肠杆菌中表达的 H Be Ag 抗原性的影响。方法 用 P C R 法,从抗- H Bc( + ) 血清标本中获得 H B V Pre c - c 基因片段,将其插入质粒 Trc99 A,重组成亚克隆 P H B I。以 P H B I为模板,扩增获得编码乙肝病毒核心蛋白1 ~140 氨基酸的基因片段,加上终止信号,分别插入质粒p G E X- 2 T 和 Trc99 A 中,各自转化后,以 I P T G 诱导,大肠杆菌表达插入基因。以 E L I S A 和 S D S- P A G E 方法测定表达产物的分子量和 H Be Ag 、 H Bc Ag 滴度。结果 在 I P T G 诱导下,大肠杆菌中分别表达 N- 端融合的 G S T- H Be Ag 融合蛋白和非融合 H Be Ag 蛋白。分子量各为41000 D 和15000 D。培养裂解物经 E L I S A 测定,融合蛋白 H Be Ag : H Bc Ag 的滴度比为256 :1 ,非融合蛋白为16 :1 。结论  N- 端融合蛋白 G S T- H Be Ag 抗原性更接近血清 H Be Ag 。  相似文献   
35.
This article describes a new and simplified surgical approach to harvest subepithelial connective tissue grafts from the palate. For this procedure, only a single incision parallel to the gingival margin is used to access the donor site for graft preparation and harvesting. Grafts of variable size and thickness can be obtained. Since no band of epithelium is removed with the connective tissue graft the palatal donor site can heal with primary intention. No stents or hemostatic agents are necessary to cover the donor area postoperatively, and suturing can be reduced to a minimum. The harvesting technique is illustrated step by step, and the clinical application of connective tissue grafts harvested with the proposed method is demonstrated with the coverage of a gingival recession.  相似文献   
36.
BACKGROUND: Hematopoietic growth factors (HGF) can suppress chemotherapy-induced programmed cell death (apoptosis) in hematopoietic cells. Although HGF can modulate the expression of apoptosis-regulatory genes, including bcl-2, bax, and p21WAF1/CIP1 in cell lines, few data address whether HGF regulate the expression of these proteins in primary acute myeloid leukemia (AML). MATERIALS AND METHODS: We evaluated the expression of bcl-2, bax, and p21WAF1/CIP1 in primary samples from patients with AML in the presence and absence of HGF. The potential association of HGF-induced changes in the levels of these proteins with inhibition of chemotherapy-induced apoptosis was further investigated. RESULTS: While a combination of steel factor (SF) and PIXY321 inhibited etoposide-induced apoptosis in 8/11 primary AML samples studied, Bcl-2 and bax protein levels were unaffected by exposure to HGF and/or etoposide. In contrast, HGF enhanced basal and etoposide-induced p21WAF1/CIP1 protein levels in 9/11 and 7/11 of the cases, respectively. In several cases, inhibition of apoptosis by HGF was seen without up-regulation of p21WAF1/CIP1 levels, suggesting that modulation of p21WAF1/CIP1 is not required for HGF-mediated inhibition of apoptosis. CONCLUSIONS: These data indicate that HGF-mediated inhibition of chemotherapy-induced apoptosis in primary AML samples is not mediated through changes in Bcl-2, bax, and p21WAF1/CIP1 protein levels.  相似文献   
37.
From March to July 1989, nine patients at risk for peripheral artery disease underwent intraoperative Nd:YAG laser angioplasty using angioscopy at the Veterans General Hospital (Taipei, Taiwan, Republic of China). Following the laser angioplasty, balloon dilatation was performed in all cases. Eight men and one woman at an average age of 68 were included in the study (range: 58 to 78 years old). Ischemic symptoms included five patients with disabling claudication, four with pain at rest and one with gangrene on the toes. Eight of the nine patients had complete occlusions ranging from 2 to 19 cm in length. Two patients had high degree multiple segmental stenosis of the superficial femoral artery from 1 to 2 cm in length. Initial clinical success (indicated by relief of symptoms and increase in Doppler ankle pressure and index) and improvement in the angiographic luminal diameter was noted in 9 of 10 occluded vessels (90%) that underwent Nd:YAG laser treatment which was delivered at 10 to 12 watts through laser probes. Prelaser intraluminal diameter increased from 0.05 +/- 0.07 to 0.53 +/- 0.07 mm, Doppler ankle pressure index rose from 0.51 +/- 0.12 to 0.81 +/- 0.12, Doppler ankle pressure increased from 62.44 +/- 16.10 to 104 +/- 21.21 mmHg and the amplitude of pulse volume recorder at ankle level rose from 5.77 +/- 2.80 to 12.11 +/- 2.77 mm as compared with prelaser therapy (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
38.
瘤内注射重组人p53腺病毒治疗晚期肺癌临床试验观察   总被引:1,自引:0,他引:1  
目的 观察重组人p53腺病毒注射液(rAd-p53)在晚期肺癌治疗中的疗效和毒副反应。方法 12例IIIb-IV期肺癌及3例肺转移癌,CT定位经皮肺穿刺瘤内注射rAd-p53,1 次/周×4/疗程;通过临床观察、CT及病理对照及短期随访进行评价。结果 治疗后2 月观察肿瘤缩小5例(33.3%),无变化7例(46.7%),增大3例(20%);治疗后病理观察:癌组织坏死,癌细胞稀少(6/11,54.5%);除自限性发热外,无明显毒副反应。结论rAd-p53瘤内注射治疗肺癌,无明显毒副作用,能较好地抑制局部肿瘤的发展,尤其对失去手术机会,不能耐受放化疗的患者,是一种可行的有前景的方法。  相似文献   
39.
Three experiments were conducted to study the uptake of oral beta-carotene by blood plasma and leukocytes in domestic cats. In Experiment 1, mature female Tabby cats (12 mo old) were given once orally 0, 10, 20 or 50 mg of beta-carotene and blood taken at 0, 12, 24, 30, 36, 42, 48 and 72 h after dosing. Concentrations of plasma beta-carotene increased in a dose-dependent manner. Peak concentrations were observed at 12-24 h and declined gradually thereafter. The half-life of plasma beta-carotene was 12-30 h. In Experiment 2, cats were dosed daily for six consecutive days with 0, 1, 2, 5 or 10 mg beta-carotene. Blood was sampled once daily at 12 h after each feeding. Daily dosing of cats with beta-carotene for 6 d resulted in a dose-dependent increase in circulating beta-carotene. Experiment 3 was designed to study the uptake of beta-carotene by blood leukocytes. Cats were fed 0, 5 or 10 mg of beta-carotene daily for 14 d. Blood leukocytes were obtained on d 7 and 14 to determine beta-carotene content in whole lymphocytes and in subcellular fractions. Blood lymphocytes took up large amounts of beta-carotene by d 7 of feeding. Furthermore, beta-carotene accumulated mainly in the mitochondria (40-52%), with lower amounts accumulating in the microsomes (20-35%), cytosol (15-34%), and nuclei (1.5-6%). Therefore, domestic cats readily absorb beta-carotene across the intestinal mucosa and transfer the beta-carotene into peripheral blood leukocytes and their subcellular organelles. beta-Carotene uptake kinetics show that some aspects of beta-carotene absorption and metabolism in cats are similar to those of humans.  相似文献   
40.
止痛活血化瘀药实验研究   总被引:5,自引:0,他引:5  
本文研究了止痛活血化瘀药对血液流变性的影响。两类止痛活血化瘀药在改善红细胞聚集性、变形性等血液流变性诸参数的作用是明显不同的。结果表明活血散瘀类药可明显改善四项红细胞流变性参数,即通过降低红细胞表明电荷以增加细胞间的排斥力,防止红细胞聚集,改善变形性,降低纤维蛋白元含量,降低血液粘度,改善血液流变性。另一方面,祛风行气类药则可降低血小板聚集性和粘附性。因此,止痛活血化瘀药的作用机理是不同的  相似文献   
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