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1.
报道了一个同时测定转化胆甾醇发酵液中雄甾-4烯-3,17二酮(4AD)、雄甾-1,4二烯-3,17二酮(ADD)和胆甾醇的气相色谱内标法。使用FID检测器。玻璃柱长1.6m,内径3mm,内装涂有2%OV-17的60~80目Cromosorb W(AW-DMOS)担体。进样口温度285℃,柱温275℃。以氮作载气,流量50ml/min,用丙酸睾丸酮作内标物。在实验条件下,发酵液中各主要成分和杂质分离良好,便于定量。结果表明,4AD、ADD和胆甾醇的浓度与Ai/As的线性范围:4AD为0.1~1.8mg/ml(γ=0.9993);ADD为0.1~1.8mg/ml(γ=0.9994);胆甾醇为0.2-3.6mg/ml(γ=0.9991)。平均回收率依次为97.91±2.34(SD)%,95.88±1.21(SD)%,100.3±1.93(SD)%。变异系数分别为2.39%、1.26%、1.92%。 相似文献
2.
Ahmed M. Zihni Ikechukwu Ohu Jaime A. Cavallo Jenny Ousley Sohyung Cho Michael M. Awad 《Surgical endoscopy》2014,28(8):2459-2465
Introduction
Robotic surgery may result in ergonomic benefits to surgeons. In this pilot study, we utilize surface electromyography (sEMG) to describe a method for identifying ergonomic differences between laparoscopic and robotic platforms using validated Fundamentals of Laparoscopic Surgery (FLS) tasks. We hypothesize that FLS task performance on laparoscopic and robotic surgical platforms will produce significant differences in mean muscle activation, as quantified by sEMG.Methods
Six right-hand-dominant subjects with varying experience performed FLS peg transfer (PT), pattern cutting (PC), and intracorporeal suturing (IS) tasks on laparoscopic and robotic platforms. sEMG measurements were obtained from each subject’s bilateral bicep, tricep, deltoid, and trapezius muscles. EMG measurements were normalized to the maximum voluntary contraction (MVC) of each muscle of each subject. Subjects repeated each task three times per platform, and mean values used for pooled analysis. Average normalized muscle activation (%MVC) was calculated for each muscle group in all subjects for each FLS task. We compared mean %MVC values with paired t tests and considered differences with a p value less than 0.05 to be statistically significant.Results
Mean activation of right bicep (2.7 %MVC lap, 1.3 %MVC robotic, p = 0.019) and right deltoid muscles (2.4 %MVC lap, 1.0 %MVC robotic, p = 0.019) were significantly elevated during the laparoscopic compared to the robotic IS task. The mean activation of the right trapezius muscle was significantly elevated during robotic compared to the laparoscopic PT (1.6 %MVC lap, 3.5 %MVC robotic, p = 0.040) and PC (1.3 %MVC lap, 3.6 %MVC robotic, p = 0.0018) tasks.Conclusions
FLS tasks are validated, readily available instruments that are feasible for use in demonstrating ergonomic differences between surgical platforms. In this study, we used FLS tasks to compare mean muscle activation of four muscle groups during laparoscopic and robotic task performance. FLS tasks can serve as the basis for larger studies to further describe ergonomic differences between laparoscopic and robotic surgery. 相似文献3.
Ikechukwu R. Obidike Lawrence Okonkwo Aka Valentine U. Omoja Shodeinde Vincent O. Shoyinka Theodore Nkire Kamalu Silvanus Maduka Anika 《Comparative clinical pathology》2012,21(6):1457-1462
This study investigated the testicular morphology as well as the gonadal and extra-gonadal sperm reserves of West African Dwarf (WAD) goats exposed to graded levels of 2,4-dichlorophenoxyacetic acid (2,4-D). Twenty male WAD goats of five goats per group were used for this study. Goats in groups A, B and C received low [75?mg/kg body weight (BW)], medium (100?mg/kg BW) and high (125?mg/kg BW) dose levels of 2,4-D, respectively. The group D goats served as the control. On day?112, goats in the four groups were sacrificed and the testicular and epididymal sperm reserves were determined. Histopathologic changes in the testis of the 2,4-D-exposed and control goats were also assessed. The mean number of spermatozoa in the testes and the various segments of the epididymides decreased significantly (p?<?0.05) in all the treatment groups relative to the control. Combined testicular sperm reserve per millilitre for the treatment groups (group A—19.61?±?2.63?×?108, group B—12.02?±?1.02?×?108 and group C—9.95?±?0.97?×?108) reduced significantly (p?<?0.05) relative to the mean value (23.52?±?4.43?×?108) of the control—group D. The total epididymal sperm reserve per millilitre in the treatment groups (group A—24.25?±?4.19?×?108, group B—17.18?±?2.57?×?108 and group C—17.88?±?2.89?×?108) was also found to be significantly (p?<?0.05) lower than the mean value (40.85?±?11.24?×?108) for the control—group D. This reduction in the testicular and epididymal sperm counts of the 2,4-D-exposed WAD goats in this study suggest disruption in spermatogenic activity, which may lead to low productivity. Variable degrees of circulatory disturbances were observed in the testis sections of 2,4-D-exposed goats. 相似文献
4.
Responses of pulmonary platelet-derived growth factor peptides and receptors to hyperoxia and nitric oxide in piglet lungs 总被引:2,自引:0,他引:2
Zhang X Reinsvold P Thibeault DW Ekekezie II Rezaiekhaligh M Mabry SM Buch S Truog WE 《Pediatric research》2005,57(4):523-529
The peptides platelet-derived growth factor-A (PDGF-A) and especially -B have important roles in lung development. The effect of hyperoxic exposure with and without inhaled nitric oxide (iNO) on lung expression of PDGF and its receptors is unknown. We hypothesized that hyperoxia exposure would suppress mRNA expression and protein production of these ligands and their receptors. The addition of iNO to hyperoxia may further aggravate the effects of hyperoxia. Thirteen-day-old piglets were randomized to breathe 1) room air (RA); 2) 0.96 fraction of inspired oxygen (O2), or 3) 0.96 fraction of inspired oxygen plus 50 ppm of NO (O2+NO), for 5 d. Lungs were preserved for mRNA, Western immunoblot, and immunohistochemical analyses for PDGF-A and -B and their receptors PDGFR-alpha and -beta. PDGF-B mRNA expression was greater than that of PDGF-A or PDGFR-alpha and -beta in RA piglet lungs (p<0.05). Hyperoxia with or without iNO reduced lung PDGF-B mRNA and protein expression relative to the RA group lungs (p<0.01). PDGF-B immunostain intensity was significantly increased in the alveolar macrophages, which were present in greater numbers in the hyperoxia-exposed piglet lungs, with or without NO (p<0.01). PDGFR-beta immunostaining was significantly increased in airway epithelial cells in O2- and O2+NO-exposed piglets. PDGF-A and PDGFR-alpha immunostain intensity and distribution pattern were unchanged relative to the RA group. Sublethal hyperoxia decreases PDGF-B mRNA and protein expression but not PDGF-A or their receptors in piglet lungs. iNO neither aggravates nor ameliorates this effect. 相似文献
5.
Ekekezie II Thibeault DW Simon SD Norberg M Merrill JD Ballard RA Ballard PL Truog WE 《Pediatrics》2004,113(6):1709-1714
6.
Endostatin and vascular endothelial cell growth factor (VEGF) in piglet lungs: effect of inhaled nitric oxide and hyperoxia 总被引:4,自引:0,他引:4
Ekekezie II Thibeault DW Rezaiekhaligh MH Norberg M Mabry S Zhang X Truog WE 《Pediatric research》2003,53(3):440-446
Pulmonary hyperoxic injury manifests as widespread alveolar-epithelial and microvascular endothelial cell necrosis, resolution of which requires angiogenesis. We investigated the hypothesis that inhaled nitric oxide (iNO) and hyperoxia each decreases lung vascular endothelial growth factor (VEGF) expression but increases endostatin and that concurrent administration of both gases will show a greater effect. Piglets were randomized to breathe for 5 d room air (RA); RA + NO (RA + 50 ppm NO), O(2) (hyperoxia, F(I)O(2) >0.96), O(2) + NO, or O(2) + NO + REC (O(2) + NO plus recovery in 50% O(2) for 72 h. After the piglets were killed, we measured lung capillary leak, VEGF mRNA, VEGF, and endostatin protein in homogenates, plasma, and lavage. VEGF mRNA decreased significantly with O(2) and O(2) + NO compared with breathing RA (p < or = 0.05). VEGF protein declined in the experimental groups with a significant reduction in the recovery group compared with the RA group (p < or = 0.05). Similar but more dramatic, endostatin declined in all groups relative to the RA group (p < 0.001). Lavage fluid VEGF protein and lung capillary leak rose significantly with O(2) and O(2) + NO compared with RA, but endostatin was unchanged. At 72 h of recovery from hyperoxia, VEGF mRNA and lavage fluid VEGF but not lung VEGF protein had normalized. Hyperoxia and iNO suppresses lung endostatin expression, but iNO unlike hyperoxia alone does not alter lung VEGF production. Hyperoxia paradoxically raises lavageable VEGF levels. This latter effect and that on VEGF mRNA level but not protein is abrogated by recovery in reduced F(I)O(2) for 72 h. 相似文献
7.
Kuo HK Sorond F Iloputaife I Gagnon M Milberg W Lipsitz LA 《The journals of gerontology. Series A, Biological sciences and medical sciences》2004,59(11):1191-1194
BACKGROUND: Little is known about what specific cognitive functions are affected by elevated blood pressure (BP) and how orthostatic BP change is related to cognitive impairment. The aim of this study was to determine the effect of BP and its postural change on cognitive functions in otherwise healthy elders. METHODS: In 70 healthy persons (mean age, 72 +/- 4 years), supine systolic BP (SBP) was assessed 3 times using a sphygmomanometer, and the average values were obtained for the analysis. After 1, 3, and 5 minutes of standing, 3 BP measurements were obtained and the orthostatic SBP changes were determined by subtracting these values from the supine average. Neuropsychological tests were administered to assess short-term and long-term verbal and visual memory, visuospatial skills, and frontal-executive functions. Participants were considered impaired in the specific cognitive performance if their scores fell below the 25th percentile of the study population. Multiple logistic regression models were used to evaluate the relation of SBP and the magnitude of orthostatic SBP decline to risk for impairment in each of the cognitive tests. RESULTS: Controlling for potential confounders, each 10 mmHg increase in supine SBP was associated with a 2.31-fold increase (95% confidence interval, 1.14 to 4.66) in risk for impairment in psychomotor speed and set shifting as measured using the Trailmaking Part-B test. There was no significant association between cognitive functions and orthostatic SBP decline at 1, 3, and 5 minutes of standing. CONCLUSION: Elevation of BP is associated with a selective impairment in executive function in otherwise healthy community-dwelling elders. 相似文献
8.
9.
Olutobi A. Sanuade MPHIL PhD Boni M. Ale MD MSc MPH Abigail S. Baldridge MS Ikechukwu A. Orji MBBS MPH PhD Gabriel L. Shedul MD MPH Tunde M. Ojo MD MSc Grace Shedul PharmD Eugenia N. Ugwuneji MSc FPCPharm Nonye Egenti MD MPH Kasarachi Omitiran MBBS FWACP Rosemary Okoli PhD Helen Eze MBBS Ada Nwankwo MBBCh Lisa R. Hirschhorn MD MPH Aashima Chopra MPH Jiancheng Ye MS Priya Tripathi MS Bolanle Banigbe MD MPH DrPH Namratha R. Kandula MD MPH Mark D. Huffman MD MPH Dike B. Ojji MD PhD the Hypertension Treatment in Nigeria Program Investigators 《Journal of clinical hypertension (Greenwich, Conn.)》2023,25(2):127-136
Fixed-dose combination (FDC) therapy is recommended for hypertension management in Nigeria based on randomized trials at the individual level. This cluster-randomized trial evaluates effectiveness and safety of a treatment protocol that used two-drug FDC therapy as the second and third steps for hypertension control compared with a protocol that used free pill combinations. From January 2021 to June 2021, 60 primary healthcare centers in the Federal Capital Territory of Nigeria were randomized to a protocol using FDC therapy as second and third steps compared with a protocol that used the same medications in free pill combination therapy for these steps. Eligible patients were adults (≥18 years) with hypertension. The primary outcome was the odds of a patient being controlled at their last visit between baseline to 6-month follow-up in the FDC group compared to the free pill group. 4427 patients (mean [SD] age: 49.0 [12.4] years, 70.5% female) were registered with mean (SD) baseline systolic/diastolic blood pressure 155 (20.6)/96 (13.1) mm Hg. Baseline characteristics of groups were similar. After 6-months, hypertension control rate improved in the two treatment protocols, but there were no differences between the groups after adjustment (FDC = 53.9% versus free pill combination = 47.9%, cluster-adjusted p = .29). Adverse events were similarly low (<1%) in both groups. Both protocols improved hypertension control rates at 6-months in comparison to baseline, though no differences were observed between groups. Further work is needed to determine if upfront FDC therapy is more effective and efficient to improve hypertension control rates. 相似文献
10.