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51.
ObjectiveTo elucidate the pharmacological bases of oral administration of Securidaca longepedunculata (S. longepedunculata) root extract as an anthelmintic in folkloric medicine.MethodsAlbino mice were infected with infective third (L3) larval stage of Heligmosomoides polygyrus (H. polygyrus) by esophageal intubation. Following establishment of the adult worms in the intestine, the mice were treated with 0–2 000 mg/kg body weight (bw) of methanolic root extract of S. longepedunculata and 100 mg/kg bw of pyrantel embonate, the reference drug in vivo. Bioactivity and larvicidal effects of the extract were tested by exposing brine shrimps (Artemia salina) to 0.00–1.00 mg/mL and the L3 stage of Heligmosomoides contortus (H. contortus) and H. polygyrus to 0.00–2.50 mg/mL of the extract in vitro.ResultsThe percentage yield of the extract was 7.13% w/w dry matter. The brine shrimps toxicity bioassay resulted in an LC50 of 74.18 μg/mL. The extract had a significant, dose–dependent larvicidal effect on the L3 stage of H. contortus and H. polygyrus with the terminal effect of 75% and 70% at the highest exposure concentrations, respectively. The extract however, did not affect the number of worm eggs per gram (epg) of fecal materials (P<0.05) and total worm burden (twb) of adult H. polygyrus in infected mice. Treatment with pyrantel embonate significant reduced both the fecal egg count and twb to 0 compared to the untreated control (P<0.05).ConclusionsThese results indicate that S. longepedunculata root extract contains potent bioactive compounds and has larvicidal effect on L3 stage of H. contortus and H. polygyrus, substantiating its use as anthelmintic in alternative medicine.  相似文献   
52.
目的:观察脑源性神经营养因子对周围神经损伤修复与再生的作用。方法:实验于2000-06/2002-08在大连医科大学神经解剖研究室完成。取健康SD大鼠24只,体质量180~200g,雌雄各半。腹腔内麻醉后,暴露左、右侧坐骨神经,在距梨状肌出口侧1.0cm处切除5mm长的坐骨神经,两断端用硅胶管桥接形成神经再生室。局部用药右侧再生室内注入0.5mL脑源性神经营养因子作为实验组,左侧再生室内注入生理盐水0.5mL作为对照组,观察局部应用脑源性神经营养因子对神经再生的影响。实验评估:术后9周对动物进行损伤肢体行为功能评价、小腿三头肌湿重测定、轴突计算机图像分析轴突数目及直径。结果:纳入SD大鼠24只,均进入结果分析。①各组动物精神状态及行为变化:对照组大鼠第3~4周时出现脱趾、溃疡加剧至第9周仍无愈合及减轻迹象。实验组于第4~5周时溃疡相继愈合,至9周时基本恢复正常。②小腿三头肌湿重测定:实验组明显重于对照组,差异显著[(0.677±0.112),(0.546±0.155)g,P<0.01]。③轴突计算机图像分析轴突计数及直径:实验组均高于对照组,差异显著[轴突数目:(2.361±0.180)×103,(1.757±0.113)×103个,P<0.01;轴突直径:(0.800±0.120),(0.530±0.170)μm,P<0.01]。结论:局部应用脑源性神经营养因子对周围神经再生有明显的促进作用。  相似文献   
53.
Hume  R; Burchell  A; Allan  BB; Wolf  CR; Kelly  RW; Hallas  A; Burchell  B 《Blood》1996,87(2):762-770
Recently, using immunohistochemical methods, we surprisingly found that endoplasmic reticulum glucose-6-phosphatase is present in human embryonic and fetal red blood cells (RBCs) but not in adult RBCs. The fact that an endoplasmic reticulum enzyme, whose major site of expression in adults is the liver, is present in human embryonic and fetal RBCs, particularly nucleated cells, indicated that it would be sensible to determine whether these cells also contain other endoplasmic reticulum enzyme systems normally found in adult liver. Therefore, we have studied the expression of other endoplasmic reticulum proteins and found that human embryonic and fetal RBC precursors contain other protein components of the glucose-6- phosphatase system, ie, the phosphate and glucose transport proteins as well as other enzymes (eg, uridine diphosphate- glucuronosyltransferases, cytochrome P450 isozymes, nicotinamide adenine dinucleotide phosphate cytochrome P450 oxidoreductase, and prostaglandin H synthase). In addition, we also found the predominantly cytosolic markers 15-hydroxyprostaglandin dehydrogenase, prostaglandins PGE2 and 13,14-dihydro-15-keto-PGE2. The expression of key enzymes that control glucose production, detoxification of endobiotics and xenobiotics, and the regulation of prostaglandin levels in embryonic and early fetal RBCs means that these cells may have an important role in protecting the developing conceptus before it establishes an efficient circulation and before all tissues fully express their normal complement of these enzymes.  相似文献   
54.
Higuchi  M; Singh  S; Chan  H; Aggarwal  BB 《Blood》1995,86(6):2248-2256
We investigated the effect of various protease inhibitors on several tumor necrosis factor (TNF)-mediated cellular responses. Treatment of a human myelogenous leukemia cell line, ML-1a, with TNF in the presence of cycloheximide triggers endonucleolytic activity and apoptotic cell death within 90 minutes. The general serine protease inhibitor diisopropyl fluorophosphate (DFP) and the chymotrypsin-like protease inhibitor N-tosyl-L-lysyl chloromethyl ketone (TPCK) completely abrogated TNF-induced DNA fragmentation and the formation of apoptotic bodies. However, 13 other protease inhibitors, including serine protease inhibitors, did not. The addition of TPCK to cells 30 minutes after TNF treatment completely inhibited the cytokine action, indicating that TPCK-sensitive proteases are not involved in the early stages of signal transduction. TNF is cytotoxic and induces differentiation in ML-1a cells after a 3-day incubation. TPCK had no effect on the TNF-induced cytotoxicity and differentiation, indicating that TPCK-sensitive proteases are specific for DNA fragmentation. TPCK also blocked TNF-induced activation of nuclear factor (NF)-kappa B. The dose-response and the time-course of the inhibitor, however, indicated that the site of action of TPCK for NF-kappa B activation and for DNA fragmentation are quite distinct. Therefore, we conclude that TNF activates two distinct TPCK-sensitive pathways, one leading to apoptosis and the other to NF-kappa B activation.  相似文献   
55.
Little is known about the development of dietary patterns during toddlerhood and the relation to growth and health. The study objective was to characterise the development of dietary patterns from 9–36 mo of age and investigate the association to body size, body composition and metabolic risk markers at 36 mo. Food records were filled out at 9, 18 and 36 mo of age (n = 229). Dietary patterns were identified by principal component analysis (PCA). Three dietary patterns were identified: Transition Food, Healthy Food and Traditional Food. The course of development in dietary patterns from 9–36 mo indicated tracking for a relatively large group of participants in the three patterns. Transition Food and Healthy Food were associated with some of the investigated outcomes. Children with lower adherence to the Transition Food pattern than average at 18 and 36 mo irrespectively of intake at 9 mo had higher BMI z-scores at 36 mo. Similar trend was identified for higher fat mass indices. Children with lower adherence to the Healthy Food pattern than average at all three ages compared to children with higher adherence to the Healthy Food pattern at the first two registrations, 9 and 18 mo had higher total cholesterol and LDL. Hence, this could represent undesirable development of dietary patterns in toddlers. In conclusion, development of dietary patterns can be exploratory characterised by PCA and related to potential cardiovascular risk markers in toddlers even within a relatively homogeneous population with a high socioeconomic status. The tracking of dietary patterns from 9 mo of age indicates a need for early and sustained promotion of healthy diets.  相似文献   
56.
在过去的20年,金属及其代谢过程对神经疾病的影响引起了神经科学家的极大兴趣。近年来大量文献报道,铁、铜、锰和锌作为重要的神经化学因子与目的蛋白相互作用导致了与疾病病理生理密切相关的反应。  相似文献   
57.
Autism Spectrum Disorders (ASDs) are characterized by the presence of impaired development in social interaction and communication and the presence of a restricted repertoire of activity and interests. While numerous treatments for ASDs have been proposed, very few have been subjected to rigorous scientific investigation. Hyperbaric oxygen therapy (HBOT) has been recently popularized as a treatment for the symptoms of ASDs. The purpose of this study was to test the hypothesis that HBOT would have a beneficial effect on ASD symptoms in the context of a double-blind placebo-controlled trial. This randomized double-blind placebo-controlled trial compared HBOT used to deliver 24% oxygen at 1.3 atmospheric pressure (n = 18) to placebo (n = 16) in children with Autistic Disorder. Both direct observational measures of behaviors symptomatic of autism and standardized psychological assessments were used to evaluate the effects of the treatment. No differences were detected between HBOT and placebo groups across any of the outcome measures. The present study demonstrates that HBOT delivered at 24% oxygen at 1.3 atmospheric pressure does not result in a clinically significant improvement of the symptoms of Autistic Disorder.  相似文献   
58.
Burns is a preventable tragedy, which is unfortunately still common in India. The possibility of disfigurement, death and emotional trauma as a result of burns is a shattering experience to the victim as well as his/her family. Proper initial management can salvage many such unfortunate victims. Burns patients require close monitoring, barrier nursing and sympathetic attitude of medical and paramedical staff in a burns ICU to have a reasonable chance of survival.Key Words: Burns, Inhalation injury, Resuscitation, Wound management  相似文献   
59.
This study is a retrospective review of the clinical results of patients treated with thoracic pedicle screws using the "funnel technique." The objective is to report the clinical results of patients treated with thoracic pedicle screws using the funnel technique for screw placement. A total of 115 patients treated with the use of at least one thoracic pedicle screw were retrospectively identified. All patients were treated at a single medical center, under the senior author's supervision. Twenty-five different residents were responsible for placing 50-60% of these screws, and five different fellows and the senior author placed the remainder. The accuracy of screw placement and the complications related to the use of thoracic pedicle screws were analyzed by assessing intraoperative and postoperative charts and radiographs. There were 115 patients (age range 9-82 years) with the average follow-up period of 17 months. The total number of screws used was 348; the screw diameter ranged from 4.0 to 7.75 mm. There were no vascular or pulmonary complications. There was no iatrogenic neurologic injury, except for one patient who developed a transient anterior thigh numbness from intraoperative positioning. In fracture patients, 35% (10 of 28) had documented neurologic improvement postoperatively. There were no obviously misplaced pedicle screws on detailed review of intraoperative and postoperative radiographs. No screws had to be electively removed for complications related to misplacement. There were four broken screws, one broken rod, two loose screws, and three connector disengagements. Two patients had deep infections and four patients had pseudarthrosis requiring additional surgery. The clinical results proved that thoracic pedicle screws can be safely placed with the funnel technique.  相似文献   
60.
High-resolution real-time ultrasonography of thyroid nodules   总被引:2,自引:0,他引:2  
Scheible  W; Leopold  GR; Woo  VL; Gosink  BB 《Radiology》1979,133(2):413-417
High-resolution real-time ultrasonography was used to evaluate 98 patients with palpable abnormalities of the thyroid and positive isotopic studies. It confirmed 37 of 73 (51%) suspected solitary nodules. Of 25 patients thought to have multinodular goiter, sonography was supportive in 21 (84%). In patients with adenoma or adenomatous nodules, characteristic features included a sonolucent "halo". Colloid nodules tended to be more sonolucent than normal thyroid tissue, whereas Hashimoto thyroiditis was characterized by an enlarged gland and decreased echogenicity.  相似文献   
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