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51.
The development of intestinal failure-associated liver disease (IFALD) in pediatric and adult patients on parenteral nutrition is usually multifactorial in nature due to nutritional and non-nutritional causes. The role of lipid therapy as a contributing cause is well-established with the pathophysiological pathways now better understood. The review focuses on risk factors for IFALD development, biological effects of lipids, lipid emulsions and the mechanisms of lipid toxicity observed in laboratory animals followed by a synopsis of clinical studies in pediatric and adult patients. The introduction of fish oil-based lipid emulsions that provide partial or complete lipid replacement therapy has resulted in resolution of IFALD that had been associated with soybean oil-based therapy. Based on case reports and cohort studies in pediatric and adult patients who were at risk or developed overt liver disease, we now have more evidence that an early switch to partial or complete fish oil–based lipid therapy should be implemented in order to successfully halt and reverse IFALD.  相似文献   
52.
Mixed tumour of the skin is a rare adnexal tumour of sweat gland origin, which can be benign or malignant. Histologically, it is defined by the presence of epithelial, myoepithelial and mesenchymal elements. The latter can take several forms, but both bone formation and cartilage formation are independently rare features. We present three rare cases of mixed tumour of the skin. Two of these displayed both mature bone and cartilaginous mesenchymal elements, while the third displayed mature bone formation without cartilage.  相似文献   
53.
IntroductionPleomorphic adenoma is the most common benign salivary gland neoplasm. The majority of cases occur in the major salivary glands; however, they can also originate from the minor salivary glands. The nasopharynx is an uncommon site, but it has been reported in the literature. The characteristic difference of our report from the literature is the young age of our patient and his previous unremarkable medical or surgical history.The objective of this report is to present a case of salivary gland pleomorphic adenoma, discuss radiological and histopathological findings and treatment options.Case presentationHerein we report a case of a 25-year-old male patient presenting with a long-term history of snoring, mouth breathing, and progressive left nasal obstruction. After examining the patient and confirming the diagnosis, patient successfully underwent tumor resection using a combined transnasal/transoral endoscopic approach with no complications following surgery and significant improvement of the previously reported symptoms.DiscussionPleomorphic adenoma of the minor salivary glands can occur anywhere throughout the distribution sites of these glands such as: along the upper aerodigestive tract, parapharyngeal fat spaces, soft palate, the sinonasal, and nasopharyngeal areas.ConclusionThe occurrence of pleomorphic adenoma in uncommon sites has been reported in the literature, and the nasopharynx is considered to be one of these uncommon sites. The mainstay of treatment for nasopharyngeal pleomorphic adenoma is surgical excision as they can grow to giant sizes if left untreated.  相似文献   
54.
55.
Natriuretic peptides have not only natriuretic/diuretic but also hypotensive activities, and the decreased renal perfusion caused by the excessive hypotension is known to attenuate the diuretic actions. The present study was designed to examine the relationship between the dosing (intravenous constant infusion) rates and the diuretic actions of -rat atrial natriuretic peptide (-rANP) and rat brain natriuretic peptide (rBNP) in rats, and population (nonlinear mixed effect model) analysis was applied to these complicated diuretic actions. The intrinsic diuretic activities of -rANP and rBNP could be analyzed, and the effects of blood pressure, heart rate, and also inhibition of degradation enzyme on the diuresis of natriuretic peptides were estimated simultaneously. The population analysis was useful for analyzing such pharmacodynamic data for which the individual analysis could not be applied easily.  相似文献   
56.
Bile salts and synthetic surfactants have been used to promote nasal absorption of peptide drugs. Although a marked increase in nasal absorption has been achieved, this may not be adequate and the possibility of adjuvant-induced membrane toxicity exists. The present study employs a rat in situ nasal perfusion technique and mixed micelles between sodium glycocholate (NaGC) and various lipids as potential nasal absorption enhancers of a stable model dipeptide, [D-Arg2]kyotorphin. NaGC alone enhanced the nasal absorption of the dipeptide in a concentration-dependent manner. When linoleic acid was added to form mixed micelles with NaGC, the absorption was further enhanced (P < 0.01). The effect of mixed micelles was synergistic and much greater than with single adjuvants. Increasing ionic strength was found to increase the adjuvant activity of both NaGC and NaGC–lipid mixed micelles. Structure of the lipid component of the mixed micelles also affected the adjuvant potency. Oleic acid, a cis-unsaturated fatty acid, was more effective than elaidic acid, the trans-isomer, whereas cis-linoleic acid and trans-linolelaidic acid were equally effective ( = 0.05). Mixed micelles of mono-glycerides such as monoolein and monolinolein were also more effective than NaGC alone ( = 0.05). Micellar solubilization of these polar lipids by NaGC appears to be important for nasal absorption enhancement to occur. Reversal of the membrane permeability was also observed within approximately 20–40 min after removal of the adjuvants from the rat nasal cavity. These observations are similar to the effects of mixed micelles on the rectal mucosa and may involve the same mechanism.  相似文献   
57.
目的 了解混配农药中氰戊菊酯在小鼠体内的代谢和分布。方法 以14 C -氰戊菊酯为示踪剂 ,静脉注射给药。给药后 0 .5~ 12 0min之间采 9次血样 ,8~ 96 0min之间分别对脑、心脏、肝脏和肺脏采 8次样品。样品用 β闪烁计数仪测量 ,并换算成化学浓度。用残数法计算毒代动力学参数。结果 混配农药中的氰戊菊酯的代谢符合二室开放模型。分布相T1/ 2 α为 2 .7min ,消除相T1/ 2 β为 10 6 .6min ,表观分布容积为 2 .9L/kg ,正向扩散系数k12 (0 .17min-1)大于逆向扩散系数k2 1(0 .0 77min-1)。分布浓度肺脏中最高 ,其次为肝脏、心脏、脑。结论 肺脏优势参与了氰戊菊酯的代谢过程 ,应重视此类农药的肺脏毒性。  相似文献   
58.
哈楠林 《河北医学》2000,6(3):211-213
目的:介绍新的更有效的内痔注射方式。方法:用多普勒血流仪引导注射治疗内痔出血与脱出,与单纯注射治疗对照观察。结果:一年后出血复发率治疗组为10%,对照组为119.17%(P〈0.05);内痔脱出复发率治疗组为18.25%,对照组为25%。结论:用多普勒血流仪引导注射治疗内痔能更有效的闭塞痔动脉。  相似文献   
59.
探讨环状混合痔的手术治疗方法。方法:采用交叉排列结扎术并尽量保留肛管移行区(ATZ)治疗环状混合痔,选择16例进行式探讨及疗效观察。肛门麻醉后用胃幽门螺杆菌美蓝「(HP)MB」染色液对肛缘至齿线上5.0cm处染色,ATZ呈淡蓝色,直肠粘膜深蓝色,肛管皮肤不染色。对内外痔各分为3-5个部位交叉排列式贯穿结扎,结扎点在不同平面上,术中尽量保留淡蓝色的ATZ,使痔结扎点是保保留的粘膜桥与皮桥呈网状。结果  相似文献   
60.
目的 探讨心脏直视术后危重患氧供需平衡的重要性和临床价值。指导救治,三疗效及预后,预防多器功能衰竭(MOF)的发生,使ICU监测水平跨跃到细胞水平。方法 对148例,心脏直视术后危重入ICU后,分阶段动态监测动脉,混合静脉血气,心输出量,胃粘膜PH值,对代谢这各项监测值之间相关关系进行分析。结果 动静脉血气及其差值的变化与循环,呼吸功能变化呈正在关系;APACHEⅡ评分高,SvO2低的极重患  相似文献   
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