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941.
钙和鸡冠花黄酮提取物对大鼠废用性骨质疏松的作用 总被引:4,自引:0,他引:4
目的探讨钙和鸡冠花黄酮提取物对废用性骨质疏松大鼠的作用,为骨质疏松的防治提供依据.方法选用健康SD大鼠40只,雄性.随机分为5组,第1、2组分别为正常对照和阳性对照,灌胃蒸馏水5 ml/(kg@d),第2~5组制造废用性骨质疏松大鼠模型,第3、4、5组为预防组,分别灌胃等量鸡冠花提取物,碳酸钙,鸡冠花提取物加钙溶液.实验8周后,测骨密度(BMD),股骨CT值,测血清MDA、SOD及24 h尿钙、羟脯氨酸(HOP)、尿肌酐含量等.结果阳性组与正常对照组比较股骨重、灰分重、CT值、血清钙下降,尿钙、尿HOP升高(P<0.05或0.01),预防组与阳性组比较股骨重、CT值显著增加,碳酸钙组、鸡冠花加钙组灰分重显著增加(P<0.05).与阳性组比较各预防组血清钙增加,尿钙、尿HOP减少(P<0.05或<0.01).鸡冠花组、鸡冠花加钙组与阳性组比较股骨BMD、血清SOD升高,MDA降低,单纯补钙组仅BMD升高(P<0.05或<0.01).结论鸡冠花提取物、钙对废用性骨质疏松大鼠骨质代谢均有促进作用,两者合用具有更好的预防效果,能延缓或减轻废用性骨质疏松的发生. 相似文献
942.
实验性室间隔缺损心肌血管紧张素Ⅱ受体表达的变化 总被引:1,自引:1,他引:0
目的 探讨实验性室间隔缺损 ( VSD)动物左右心室心肌血管紧张素 受体的改变。方法 建立猪实验性室间隔缺损动物模型 ,术后 1月取左右心室组织 ,通过放射性配体受体结合分析法测定每 10 6个细胞上血管紧张素 受体 ( AT1 R、AT2 R)的最大结合量 ( Bmax)和平衡解离常数 ( KD)。结果 假手术组与正常组动物受体的 Bmax和KD改变无统计学意义 ,手术组动物左室 AT1 R、右室 AT1 R和 AT2 R的 Bmax值 (分别为 188.42± 13 3 .97、2 72 .14±2 3 2 .74、40 .42± 3 4.76fmol/ 10 6 ,对照组 AT1 R和 AT2 R的 Bmax值左室为 2 9.2 0± 19.5 0和 2 .90± 0 .64 ,右室为76.72± 5 1.2 1和 9.63± 1.2 7fm ol/ L )增高明显 ( P<0 .0 5 )。结论 心内左向右所引起的心室容量负荷过重 ,导致AT1 R的表达增高 ,是 VSD心室肥厚及重构的重要机制 ;AT2 R在右心室表达增高 ,可能是中等程度容量负荷的VSD容易出现左室肥厚而非右室肥厚的原因 相似文献
943.
P K Woolf E M Lorsung K S Edwards K I Li S J Kanengiser R M Ruddy M H Gewitz 《Pediatric emergency care》1991,7(6):334-336
The incidence of cardiac involvement in Lyme disease (LD) has been estimated to be 4 to 10% in adults, with conduction and rhythm disturbances noted most frequently. To assess the frequency of electrocardiographic abnormalities in children with LD, we prospectively performed 12-lead electrocardiograms in 32 randomly selected children presenting with LD between May and September 1989. No patient had symptoms of cardiac involvement. Using defined diagnostic criteria, combining symptoms, signs, serology, and residence in or travel to an endemic area, 14 patients were classified as having definite LD and 10 were categorized as probable. The incidence of electrocardiographic abnormalities in the definite group was 29% (4/14), including two patients with 1 degree atrioventricular block, one with left axis deviation, and one with ventricular ectopy. Thirty percent (3/10) of the probable group had abnormal ECGs, including one with ST-T wave abnormalities, one with prominent sinus arrhythmia, sinus bradycardia, and wandering atrial pacemaker, and one with ectopic atrial bradycardia. No patient required cardiac therapy. The incidence of abnormal ECG findings in this group of children with either probable or definite LD was thus 29%, with 1 degree atrioventricular block noted most frequently. When the diagnosis of LD is highly suspected, an electrocardiogram may be a useful screening test for cardiac involvement. 相似文献
944.
Head injuries incurred by children and young adults during informal recreation. 总被引:1,自引:1,他引:0
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S P Baker C Fowler G Li M Warner A L Dannenberg 《American journal of public health》1994,84(4):649-652
To examine injuries related to playground equipment, children's vehicles, roller skates, and skateboards, 1991 data on emergency room patients younger than 25 years in the Consumer Product Safety Commission's 91 surveillance hospitals were used. Head injury was the primary diagnosis for an estimated 58,480 patients, exceeding the total number of head injuries to bicyclists younger than 25 years. The head injury rate decreased with age. The large number and high rate of head injuries in children involved in a variety of recreational activities suggests the value of multipurpose helmets. 相似文献
945.
尼莫地平复方丹参注射液治疗新生儿缺氧缺血性脑病疗效观察 总被引:1,自引:0,他引:1
目的观察尼莫地平联合复方丹参注射液治疗新生儿缺氧缺血性脑病(HIE)的疗效.方法 128例HIE患儿随机分为复方丹参注射液组32例,尼莫地平组,尼莫地平加复方丹参注射液,与对照组.结果复方丹参注射液组、尼莫地平组、尼莫地平加复方丹参注射液治疗组总有效率分别为81.3%(26/32)、80.0%(24/30)、97.1%(34/35),对照组总有效率为51.6%(16/31),P<0.05.结论尼莫地平与复方丹参注射液在治疗HIE时有协同作用,疗效显著,未见副作用发生. 相似文献
946.
947.
本研究应用层粘连蛋白(LN)抗体,对27例乳腺癌、5例乳腺良性病变进行了免疫组织化学研究。结果发现乳腺良性病变时,LN以均匀完整的线型阳性反应显示在乳腺导管及小叶基膜处。乳腺癌时,LN的染色表现为癌细胞胞浆内弥漫状阳性反应。27例乳腺癌中,癌细胞LN染色强度不同,伴有转移的乳腺癌LN染色多数较强,强度在++~的为7/12(58.3%);不伴有转移的病例,LN染色多数较浅或为阴性,强度在++~+++的病例为3/15(20%)。说明癌细胞内源性LN染色强弱与肿瘤转移密切相关,内源性LN的合成可能改变肿瘤细胞的浸润活性。 相似文献
948.
内镜鼻胆管引流术在腹腔镜和开腹胆总管探查术中的应用 总被引:10,自引:7,他引:3
目的 评价内镜鼻胆管引流术 (Endoscopicnasobiliarydrainage ,ENBD)配合腹腔镜和常规开腹手术治疗胆总管结石的疗效。 方法 回顾分析 1997年 1月~ 2 0 0 1年 7月应用ENBD配合完成腹腔镜胆总管探查、I期缝合术 4 4例及开腹胆总管探查、I期缝合术 34例。 结果 78例均手术成功 ,术后无胆漏、胆道出血、胆管炎等并发症。术中结石取净率 10 0 % (78 78)。术后住院时间 :腹腔镜组为 (6 2±1 3)d ,开腹组为 (7 4± 2 1)d。随访 5 7例 ,时间 (1~ 4 5 )年 ,平均 2 6年 ,腹部彩色B超检查无胆管狭窄及结石复发。 结论 ENBD配合腹腔镜和开腹胆总管探查取石、胆总管I期缝合术安全、可靠。 相似文献
949.
Masataka Sakane Ross J. Fox Savio L-Y. Woo Glen A. Livesay Guoan Li Freddie H. Fu 《Journal of orthopaedic research》1997,15(2):285-293
The anterior cruciate ligament has a complex fiber anatomy and is not considered to be a uniform structure. Current anterior cruciate ligament reconstructions succeed in stabilizing the knee, but they neither fully restore normal knee kinematics nor reproduce normal ligament, function. To improve the outcome of the reconstruction, it may be necessary to reproduce the complex function of the intact anterior cruciate ligament in the replacement graft. We examined the in situ forces in nine human anterior cruciate ligaments as well as the force distribution between the anteromedial and posterolateral bundles of the ligament in response to applied anterioi tibial loads ranging from 22 to 110 N at knee flexion angles of 0–90°. The analysis was performed using a robotic manipulator in conjunction with a universal force-moment sensor. The in situ forces were determined with no device attached to the ligament, while the knee was permitted to move freely in response to the applied loads. We found that the in situ forces in the anterior cruciate ligament ranged from 12.8 ± 7.3 N under 22 N of anterior tibial load applied at 90° of knee flexion to 110.6 ± 14.8 N under 110 N of applied load at 15° of flexion. The magnitude of the in situ force in the posterolateral bundle was larger than that in the anteromedial bundle at knee flexion angles between 0 and 45°, reaching a maximum of 75.2 ± 18.3 N at 15° of knee flexion under an anterior tibial load of 110 N. The magnitude of the in situ force in the posterolateral bundle was significantly affected by knee flexion angle and anterior tibial load in a fashion remarkably similar to that seen in the anterior cruciate ligament. The magnitude of the in situ force in the anteromedial bundle, in contrast, remained relatively constant, not changing with flexion angle. Significant differences in the direction of the in situ force between the anteromedial bundle and the posterolateral bundle were found only at flexion angles of 0 and 60° and only under applied anterior tibial loads greater than 66 N. We have demonstrated the nonuniformity of the anterior cruciate ligament under unconstrained anterior tibial loads. Our data further suggest that in order for the anterior cruciate ligament replacement graft to reproduce the in situ forces of the normal anterior cruciate ligament, reconstruction techniques should take into account the role of the posterolateral bundle in addition to that of the anteromedial bundle. 相似文献
950.
It is documented that alkaline phosphatase (AP) plays an important role in bone mineralization. Considering that TN-AP is
expressed in periodontal ligament fibroblasts, renal epithelial cells, and vascular endothelial cells, and that TN-AP is both
a calcium-/phosphate-binding protein and a phosphohydrolytic enzyme, we hypothesize that membrane-bound AP also plays an important
role in the initiation of physiological and pathological mineralizations in tissues other than bone and cartilage. To test
this hypothesis, nonosteoblast cell lines, including a fibroblast line, a renal epithelial line, and a capillary endothelial
line, were stably transfected to express high levels of rat bone AP on their cell surfaces. These rat bone AP-expressing cells
were then cultured on filter membranes in the presence or absence of β-glycerol phosphate. von Kossa staining for calcium
phosphate and transmission electron microscopy with electron diffraction analysis for minerals were employed to investigate
the effect of membrane AP on extracellular calcium phosphate mineralization. Our results indicated that AP expression on these
nonosteoblast-like cell surfaces have induced extracellular hydroxyapatite (HAP) mineralization. Our findings support the
concept that membrane-bound AP contributes to extracellular apatitic mineralization by mechanisms that do not necessarily
involve its hydrolase activity. They also suggest that AP might be important for the initiation of pathological mineralization
in nonosteogenic tissues.
Received: 11 January 1996 / Accepted: 31 October 1996 相似文献