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101.
Northern blot analysis was used to demonstrate high levels of hippocampus-derived neurotrophic factor/neurotrophin-3 (HDNF/NT-3) mRNA in the embryonic day (E) 13 - 14 and 15 - 16 spinal cord. The level decreased at E18 - 19 and remained the same until postnatal day (P) 1, after which it decreased further to a level below the detection limit in the adult. In situ hybridization revealed that the NT-3 mRNA detected in the developing spinal cord was derived from motoneurons and the decrease seen at E18 - 19 was caused by a reduction in the number of motoneurons expressing NT-3 mRNA. The distribution of NT-3 mRNA-expressing cells in the E15 spinal cord was very similar to the distribution of cells expressing choline acetyltransferase or nerve growth factor receptor (NGFR) mRNA. Moreover, a striking similarity between the developmentally regulated expression of NT-3 and NGFR mRNA was noted in spinal cord motoneurons. A subpopulation of all neurons in the dorsal root ganglia expressed brain-derived neurotrophic factor (BDNF) mRNA from E13, the earliest time examined, to adulthood. These results are consistent with a trophic role of NT-3 for proprioceptive sensory neurons innervating the ventral horn, and imply a local action of BDNF for developing sensory neurons within the dorsal root ganglia. 相似文献
102.
柴胡、赤芍与醋柴胡、杭白芍对大鼠高脂血症作用的实验研究 总被引:8,自引:0,他引:8
目的观察药对柴胡、赤芍与醋柴胡、杭白芍,对高脂血症大鼠脂质代谢、血小板功能影响,比较它们作用环节的差异.方法本实验采用高脂应激造成大鼠高脂血症血瘀模型方法,观察大鼠血瘀模型脂质代谢、血小板功能的变化.结果醋柴胡、杭白芍、柴胡、赤芍对TC(cholesterol)均有显著降低作用,醋柴胡、杭白芍强于柴胡、赤芍,而两者对LDL-C(low density lipoprotein)、Lp(a)[lipoprotein(a)]也有显著降低作用,但柴胡、赤芍作用较强,和模型组比较有明显差异(P<0.05和P<0.01);醋柴胡、杭白芍对TG (triglyceride)有显著降低作用,和模型组比较有明显差异(P<0.01); 柴胡、赤芍对血小板聚集率和活化阳性率均有显著降低作用(P<0.05).结论柴胡、赤芍与醋柴胡、杭白芍可作用于引起动脉粥样硬化的不同环节,柴胡、赤芍药对在抑制血小板聚集、降低血小板活化率方面优于醋柴胡、杭白芍. 相似文献
103.
葛根提取物对未成熟大鼠乳腺、子宫发育影响的研究 总被引:10,自引:0,他引:10
目的 :研究葛根提取物对大鼠乳腺、子宫发育的影响。方法 :正常Wistar雌性大鼠 4 0只 ,体重为 6 5~85g ,随机分为正常组、雌二醇组、葛根提取物低剂量组、葛根提取物高剂量组 ,每组 10只。各组给药 7d后 ,测血清中激素 ,剥离乳腺与子宫称重。结果 :①葛根提取物能显著提高未成熟大鼠乳腺和子宫重量 ;②葛根提取物能增加大鼠血清促卵泡生成素 (FSH)、促黄体生成素 (LH)、雌二醇 (E2 )含量 ,降低泌乳素 (PRL)含量。结论 :葛根提取物能促进未成熟大鼠乳腺及子宫发育 ,为进一步开发促进青年女性乳腺及子宫发育的新药提供实验依据 ,同时为治疗先天性子宫发育不良患者提供基础资料。 相似文献
104.
正交试验法考察黄芪的提取工艺 总被引:2,自引:0,他引:2
吴立明 《中国中医药信息杂志》2003,10(11):39-40
目的:优选黄芪提取工艺。方法:采用单因素水平试验考察溶媒对黄芪甲苷提取量的影响;采用正交试验,以出膏率和黄芪甲苷含量考察水提工艺条件。结果:以水为溶媒提取最佳。水提取的最佳工艺为药材用8倍量水提取3次,每次1h。3批验证结果,出膏率30.82%,黄芪甲苷含量0.0672mg/g。结论:上述实验结果可为黄芪提取工艺的确定提供实验依据。 相似文献
105.
丹参根腐病及其微生物防治研究 总被引:5,自引:0,他引:5
丹参根腐病是由腐皮镰刀菌浸染所致的一种土传病害,近年来在四川的田间发病株率达10%-30%,导致丹参产量下降,品质变劣。对丹参根腐病的防治,一般化学农药难于有效,而且滥用化学农药合造成农药残留污染。利用有益微生物控制病原菌是一种可行的措施,本研究从生长在不同生态环境的丹参根际土样中分离了一批木霉菌株,通过室内拮抗试验和田问防病增产试验,筛选出了对腐皮镰刀菌有较强拮抗作用的哈茨木霉T23、桔绿木霉T56等菌株。田间试验结果,T23、T56对丹参根腐病的防效分别为52.3%和55.7%,与常用化学杀菌剂多菌灵的防效相当,表明木霉防治丹参根病病具有较好的应用前景。 相似文献
106.
目的 探讨残根残冠修复的临床效果。方法 对285例321颗前后牙残根残冠经过完善的根管治疗后进行铸造桩核全冠修复,并进行2年至6年的临床观察。结果 285例321颗患牙修复后成功310颗,失败11颗,成功率96.6%。结论 残根残冠经过完善的根管治疗后铸造桩核全冠修复是其目前得以保留并发挥功能的理想方法。 相似文献
107.
Absent pulmonary valve syndrome (APVS) is a rare congenital cardiac lesion. The lesion includes ventricular septal defect,
overriding aorta, and absence of the pulmonary valve, with resultant pulmonary incompetence. It has been suggested that the
pulmonary incompetence induces intrauterine dilatation of the pulmonary artery, which leads to tracheobronchial compression.
One of the presenting features in infants with APVS is severe airway obstruction, which may be difficult to manage. We report
an infant who benefited from bilateral endobronchial endoscopic stent placement. 相似文献
108.
Vascular compression of the airway: Indications for and results of surgical management 总被引:1,自引:0,他引:1
Elizabeth A. Erwin Mark E. Gerber Robin T. Cotton 《International journal of pediatric otorhinolaryngology》1997,40(2-3):155-162
Vascular compression of the airway is a significant cause of respiratory compromise in children. While the indications for surgical repair are sometimes life threatening, they can also be subtle. This retrospective study examines 45 surgical cases of tracheobronchial compromise secondary to vascular compression at a large children's hospital between July 1983 and February 1996. A total of 34 were diagnosed with innominate artery compression, ten with a double aortic arch and one with an anomalous right subclavian artery. The 45 patients, 25 male and 20 female, ranged in age from 12 days to 11 years at surgery (average 13 months). A total of 21 (47%) presented with proven or suspected episodes of cyanosis or apnea. All 45 patients had evidence of vascular compression during microlaryngoscopy and bronchoscopy. The diagnosis was confirmed by magnetic resonance imaging (MRI) in 23/45 (51%), barium swallow in 22/45 (49%) and aortogram in 3/45 (7%). There was one death. One patient had a tracheotomy before surgery and continues to require it after surgery. Complete resolution of symptoms was achieved in 39/45 (87%) with five requiring more than one operation before their symptoms resolved completely. A total of four patients experienced a recurrence of symptoms within a variable length of time after surgery. Surgical indications and treatment alternatives will be discussed. 相似文献
109.
P. Dervanian L. Macé T.A. Folliguet A. di Virgilio J.M. Grinda J.F. Fuzellier B. De Geeter P. Morville J.Y. Neveux 《Pediatric cardiology》1998,19(4):369-373
The prognosis of Marfan syndrome in both adult and pediatric patients is primarily related to the cardiovascular complications.
In infantile Marfan syndrome, although involvement of the mitral valve is the most frequently encountered cardiovascular lesion,
the aortic root can be more worrisome because of its excessive dilatation, leading to aortic insufficiency or dissection.
If the role of elective surgery is relatively well defined for adult patients, it is still debated during childhood. We report
two patients, aged 22 months and 5 years, each presenting an aortic root aneurysm related to Marfan syndrome, and each treated
with the Bentall procedure without specific age-related mortality or morbidity. These two patients experienced normal growth
and were free of any complication for a follow-up period of 8 and 2 years, respectively. More than an absolute value of the
aortic root dimension, it is the conjunction of the rate of progression of the aortic root dilatation, the degree and the
duration of the aortic valve regurgitation, and its resulting left ventricular dysfunction that must be taken into consideration
in choosing the surgical option. 相似文献
110.
M. McCullagh J. Harper M. C. Pitt D. Jones L. Spitz 《Pediatric surgery international》1998,13(5-6):449-450
Proteus syndrome is a multi–organ disorder, a prime feature of which is localized gigantism, usually clinically obvious.
Symptoms secondary to hypertrophy of nerves has not been previously recognized as a part of the syndrome.
Accepted: 16 May 1997 相似文献