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141.
本文应用核磁共振法(NMR)测定了几种混合体系的 HLB 值与混合体系中各组分的 HLB 值。实验结果表明,混合体系中各组分在核磁共振图谱中的积分曲线高度也具有加和性。混合体系的 HLB 值是体系中各组分 HLB 值的加权平均值。因此,对混合体系的 HLB 值可以应用 NMR 法直接测定,也可应用 NMR 法测定各组分的 HLB值,通过计算求得,计算值与实测值完全一致。  相似文献   
142.
143.
The purpose of this study was to determine the dosimetric impact of a neurosurgical titanium mesh in patients treated with 6- and 18-MV photon beams. The effects of a 0.4-mm-thick titanium mesh on the dose profile at 3 regions within a solid water phantom were measured using extended dose range-2 (EDR2) film for 6- and 18-MV photon beams. All measurements were performed with the titanium mesh placed at a depth of 1.5 cm in the phantom. Films were exposed immediately above the mesh, immediately below the mesh, and at a depth of 5 cm from the surface of the phantom. The films were scanned using a scanning densitometer. In the region directly above the titanium mesh, there was an increase in dose of 7.1% for 6-MV photons and 4.9% for 18-MV photons. Directly below the titanium mesh, there was an average decrease in dose of 1.5% for 6-MV photons and an increase of 1.0% for 18-MV photons. At 5-cm depth, for 6- and 18-MV photons, there was a decrease in dose of 2.2% and 0.6%, respectively. We concluded that for cranial irradiation with high-energy photons, the dosimetric impact of a 0.4-mm titanium mesh is small and does not require modification in treatment parameters.  相似文献   
144.
Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively or on histological examination. We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was immune competent and had no past history of sinusitis. The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype of invasive fungal sinusitis and the degree of tissue invasion.  相似文献   
145.
颈椎病与中医辨证关系的探讨(附100例分析)   总被引:3,自引:0,他引:3  
目的:探讨颈椎病与中医分型的辨证关系。方法:对100例该病的影像表现与中医分型进行系统分析。结果:主要临床表现颈部活动受限,颈、肩、背部疼痛,常伴头痛、头晕、视物模糊、耳鸣等症状。风寒型以软组织所致颈曲改变为主。肝肾亏虚型、痰湿交阻型以骨质增生、椎间隙及椎间孔狭窄为主。结论:X线、CT是本病首选检查方法,能与中医辨证有机结合,对中西医治疗有重要意义。  相似文献   
146.
The general management of patients with chronic obstructive pulmonary disease and asthma is discussed. Pathophysiological mechanisms of bronchial obstruction and inflammation are briefly described. The importance of preventive measures is emphasized. Medicine prescribed in chronic obstructive pulmonary disease and asthma, their relative place in treatment schedules and route of administration are reviewed. Finally, the importance of maximal bronchodilatation in exacerbations is stressed and the few indications for antibiotic treatment are discussed.  相似文献   
147.
The Australian government established the Council on Overseas Professional Qualifications (COPQ) in 1969. In response to approaches by the occupational therapy profession, an Expert Panel in Occupational Therapy was established in 1979 in order to develop a screening examination to be used in assessing the competency of overseas trained occupational therapists. This paper describes the development of the COPQ examination for all overseas qualified occupational therapists wishing to work in Australia; the experience of candidates since its inception in 1983; and the problems associated with achieving recognition of the COPQ examination throughout Australia given the lack of uniform recognition procedures in the various States and Territories. The need for a consistent national approach to the policy of recognition and employment of overseas trained occupational therapists is addressed, with stress placed on the need for all employer groups, in both the public and the private sectors, to cooperate with COPQ's assessment procedures.  相似文献   
148.
Seventeen patients who had undergone extensive small bowel resection were studied for calcium absorption (FACa) and plasma vitamin D metabolites. FACa was measured by a double radio-tracer technique and expressed as percentage of total oral dose. FACa was decreased compared with controls (34%, range: 3-46 v 65%, range: 57-73, P less than 0.01). A positive correlation (r = 0.49, P = 0.05) was found between FACa and the remaining length of small bowel (SBL). As wide variations in both SBL and duration after surgery were observed among the seventeen investigated patients, we were led to individualize less heterogeneous subgroups of patients. Better correlations were found when the patients were divided into two subgroups according to whether the time interval between the resection and the investigation was shorter (r = 0.75, n = 11, P less than 0.02) or longer (r = 0.89, n = 6, P = 0.05) than 2 years. In thirteen patients who had a SBL shorter than 100 cm, a positive correlation was observed between FACa and the time interval after surgery (months): r = 0.65, P less than 0.05. Plasma 1,25 (OH)2D was markedly reduced in the whole group (31 pmol l-1, range: 8-108) compared with controls (103 pmol-1, range: 59-134, P less than 0.01). The present study shows that in extensively small bowel resected patients, calcium absorption is reduced, the alteration being dependent both on the length of the remnant small bowel and on the time after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
149.
氢氧化钙预防根管治疗期间急症的临床观察   总被引:1,自引:1,他引:0  
目的 观察氢氧化钙根管内封药对预防根管治疗期间急症的临床疗效。方法 使用氢氧化钙及传统根管内消毒药物樟脑对氯酚、甲醛甲酚根管内封药,观察疼痛指数并比较其根管治疗期间急症的发生率。结果 氢氧化钙封药后根管治疗期间急症的发生率最低,与传统药物相比,其差异有统计学意义。结论 氢氧化钙根管内封药。对预防根管治疗期间的急症有较好的作用。  相似文献   
150.
良性前列腺增生中医证型与尿动力学参数相关性研究   总被引:1,自引:0,他引:1  
目的:探讨良性前列腺增生(BPH)中医证型与尿动力学参数的相关性。方法:152例BPH患者,中医辨证分为肾阴不足、肾阳虚弱、瘀阻水道、脾气虚弱、肺热气郁、湿热下注、痰浊郁结七型,均进行尿动力学检查。结果:152例BPH患者中,肾阳虚弱型71例(46.71%),瘀阻水道型40例(26.31%),肾阴不足型14例(9.21%)。膀胱出口梗阻为III~VI度肾阳虚弱型有58例,瘀阻水道型有38例,其中严重梗阻(V~VI)26例。膀胱逼尿肌收缩功能极弱中(n=12),肾阳虚弱型4例,占33.33%(4/12),瘀阻水道型7例,占58.33%(7/12);膀胱逼尿肌收缩功能弱者中(n=48),肾阳虚弱型为27例,占56.25%(27/48),瘀阻水道型17例,占35.42%(17/48)。结论:BPH中医各辨证分型与膀胱出口梗阻和膀胱逼尿肌收缩力有一定的相关性,从而为中医证型的量化和客观化提供相应的证据。  相似文献   
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