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111.
有机氮源对红霉素发酵影响的具体分析   总被引:2,自引:1,他引:1  
红色糖多孢菌的摇瓶培养基中使用不同有机氮源时红霉素的效价明显不同。通过对不同有机氮源所含营养成分的逐步回归分析,我们得到有机氮源中的苏氨酸为影响红霉素效价的主要因子。最后向对照培养基中添加苏氨酸,则使红霉素的效价比对照培养基提高了22.85%。  相似文献   
112.
目的 探讨1 31 Ⅰ治疗Graves病时 ,不同的剂量计算方法与治愈率以及治疗后并发症的关系。方法 在计算治疗Graves病所需1 31 Ⅰ时 ,分别采取不同的两种计算方法 ,观察两者治愈率及并发症的发生情况 ,并做多因素对比分析。结果 治疗组较对照组 1次治愈率提高约 12 % ,近期甲状腺功能减退延续为永久性甲状腺功能减退者亦明显减少 ,治疗效果明显优于后者。结论 1 31 Ⅰ治疗剂量计算时 ,既要有公式的规范性 ,又要有根据具体情况调节的灵活性 ,即可明显提高治疗效果  相似文献   
113.
探讨小儿短暂性滑膜炎与病毒感染 ,特别是柯萨奇B组病毒 (CVB)感染的关系。方法 :采用酶联免疫吸附试验 (ELISA)对 16 2例小儿髋关节短暂性滑膜炎患儿静脉血和其中的 2 1例关节腔液进行病毒IgM抗体检测 ,柯萨奇病毒B组 (CVB)阳性者进行血清学分型及病毒分离。结果 :在 16 2例静脉血样本中病毒IgM阳性 6 2例 ,占总检数的 38.2 7% ,CVB -IgM2 6例占 16 .0 5 % ,AdV -IgM 19例占 11.73% ,CMV -IgM 10例占 6 .17% ,RSV -IgM 4例占 2 .4 7% ;在关节腔液中检出 9例CVB阳性 ,血清学分型 8例为CVB3,1例为CVB4 ,并分离出 1例CVB3。结论 :CVB和腺病毒 (AdV)是小儿髋关节短暂性滑膜炎感染的主要病毒 ,而且以CVB3为主。  相似文献   
114.
Plasma testosterone and estradiol are determined in 72 patients with abnormal high density lipoprotein. cholesterol (HDL-C) and high density lipoprotein cholesterol/total cholesterol (H/T) ratio values, and in 72 randomly chosen males with normal HDLC and H/T values. The results showed that plasma testosterone levels in the groups with abnormal HDL-C and H/T were obviously lower than those in the controls. Statistically significant differences were found in all the abnormal groups in comparison with the controls (P0.20). Testosterone levels lowered further with increasing age in the groups with abnormal HDL-C and H/T., the most obvious drops were in the groups around 56 years of age (P<0.005). The data indicate that male hormone deficiency may reduce HDL-C and H.'T and facilitate the process of atherosclero_is. Therefore, it seems rational to treat such patients with male sex hormone preparations or to use the traditional Chinese medicines which strengthen Yang (maleness) in a new attempt to treat and prevent CHD.  相似文献   
115.
四种口服头孢菌素的体外抗菌活性的比较研究   总被引:2,自引:0,他引:2  
本文报道口服Cefixime对900株需氧菌和厌氧菌的体外抗菌作用,并与其它口服的头孢克罗、头孢羟氨苄和头孢氨苄进行了比较。Cefixime对链球菌具较强作用,但对葡萄球菌的作用较差;对肠球菌无效。对肠杆菌科细菌的抗菌活性四者之中以Cefixime最强。Cefixime对头孢氨苄耐药株仍具高度活性,其MIC均值可降低60~1200倍以上。绿脓杆菌、硝酸盐阴性杆菌、鲁氏不动杆菌和产碱杆菌对Cefixime和其它3种头孢菌素的敏感性均较差。四者对厌氧菌的作用除厌氧球菌外其抗菌活性都很弱。Cefixime对β-内酰胺酶稳定,口服吸收良好,抗菌作用强,是一个值得进行临床研究的口服头孢菌素。  相似文献   
116.
A new DRB1 allele, DRB1*0902, has been identified in an individual of the Jing ethnic minority. Its sequence was confirmed by sequencing of PCR products and clones. This allele differed by three nucleotides from DRB1*09012 at positions 157, 161 and 166, and resulted in amino acid motif substitution from VAES to DAEY.  相似文献   
117.
Functional anatomy and biomechanics of the meniscus   总被引:2,自引:0,他引:2  
The meniscus is no longer considered the evolutionary remnant in the knee joint.Rather, it is now well established as an important structure that is integral to the complex biomechanics and proper functioning of the knee. The medial and lateral menisci form two crescent-shaped wedges of fibrocartilage between the femoral condyles and tibial plateaus.The knee joint biomechanics are based on a complex interaction of these intra-articular structures. The functions ascribed to the menisci include load transmission, shock absorption, stability, proprioception, joint lubrication, and joint nutrition. Load transmission generally is accepted as one of its primary functions. The menisci transmit a portion of the axial forces across the knee joint by converting this load into “hoop stresses.” This is accomplished by their unique shape, composition, and anatomic attachments. The menisci are relatively mobile structures and their motion during knee flexion also is determined by their shape and soft tissue attachments/constraints. Preservation of the meniscal functions is essential, and the authors review the basic anatomic and biomechanical concepts necessary to understand techniques for repair and restoration of these functions.  相似文献   
118.
同型半胱氨酸对胚胎海马神经元细胞的影响   总被引:1,自引:1,他引:0  
目的 观察同型半胱氨酸(homocysteine,HCY)对海马神经元细胞分化和增殖的作用机理。方法 采用大鼠胚胎海马神经元细胞进行体外培养。观察不同浓度的HCY(0.01、0.1、1.0、10.0、100.0)mmol/L对细胞分化和增殖的影响。结果 随着剂量的增加.同型半胱氨酸对胚胎海马神经元细胞分化和增殖具有抑制作用,并用流式细胞术分析证明对脂质过氧化(LPO)的影响而使得神经元蛋白质含量增高。结论 同型半胱氨酸可抑制胚胎海马神经元细胞分化和增殖的影响,HCY可能在导致神经管畸形的过程起着重要作用。  相似文献   
119.
During a 26-year period (1961-1987), a total of 18 patients with primary non-Hodgkin's lymphoma (NHL) of the paranasal sinuses and nasal cavity received radiation therapy at (University of California at Los Angeles) UCLA Medical Center. At the time of diagnosis and using the available diagnostic methods, none of these patients had clinically detectable disease beyond the paranasal sinuses. All 18 patients were staged IE by the Ann-Arbor system. When the patients were staged according to the AJC staging system from epithelial tumors, half presented with advanced T3-4 disease. Diffuse histiocytic lymphoma was the most common histology (eight cases) and maxillary sinus, the most common site of origin (11 cases). All nine T1-2 tumors received radiation therapy alone, while radiation and chemotherapy was used in seven of nine advanced T3-4 staged tumors. The mean follow-up was 71 months. At last follow-up, eight of nine T1-2 patients were rendered disease-free. In contrast, only four of nine T3-4 patients had long-term disease-free survival. Seventy-five percent of the failure occurred within 2 years. Radiation therapy alone achieves high local control in small tumors (T1-2), while large tumors (T3-4) require aggressive combined treatment, i.e., radiation and chemotherapy.  相似文献   
120.
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   
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