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991.
目的 分析主观症状及实验检查对早期干眼症患者诊断的意义。方法 对55例(109眼)已确诊的早期干眼症患者(无或仅伴有轻微体征)的临床症状及实验检查进行回顾性分析及比较。结果 患者中主观症状所占比率:干涩感94%,视疲劳感82%,异物感74%,明显高于其他症状(P〈0.05)。实验检查的阳性率:基础泪液分泌试验(Schirmer I test,SIt)35%,泪膜破裂时间检查(break-up time,BUT)85%,角结膜荧光素(fluorescent,FL)染色60%,其中BUT阳性率明显高于SIt和FL(P〈0.05)。结论 主观症状及实验检查可为早期干眼症诊断提供有利依据。  相似文献   
992.
Recently it has been suggested that the Australian snake antivenoms made by CSL Ltd. are in fact not truly monovalent and may contain antibodies to other snake venoms because the horses are injected with multiple snake venoms. It is unclear to what extent various monovalent antivenoms can neutralise the effect of other venoms, whether this is due to a mixture of antibodies or true cross-reactivity, and whether this has any clinical significance. We aimed to study the immunological and functional properties of brown snake (Pseudonaja spp.) antivenom (BSAV) and tiger snake (Notechis spp.) antivenom (TSAV) against their respective venoms using enzyme immunoassays (EIA) and in vitro clotting studies. There was significant overlap between the two antivenoms with both TSAV and BSAV being detected by EIA on brown snake venom (BSV)-coated and tiger snake venom (TSV)-coated wells, respectively. In a competition EIA, increasing amounts of immunoaffinity-purified hen anti-brown antibodies (IgYp) mixed with TSAV reduced TSAV measured on TSV-coated wells. Both BSAV and TSAV prevented the clotting activity of both venoms. IgYp also prevented the clotting activity of TSV, suggesting true cross-reactivity. The cross-reactivity of TSAV and BSAV with BSV and TSV, respectively, was likely due to each being a mixture of anti-brown and anti-tiger antibodies, but there was partial cross-reactivity demonstrated by the effect of IgYp. Single-polyvalent antivenom for brown snake and tiger snake may be feasible in the future.  相似文献   
993.
锰电焊工人某些内分泌功能研究崔金山,王薛君,张玉敏,马明月,李宏革,孙玉强,孔庆芝,窦林松,曹昆,裴秋铭,赵艳萍(沈阳医学院毒理教研室,110031)研究对象选自某建筑机械厂结构车间锰电焊作业工人51人(男42人,女9人),年龄范围21~51岁,平均...  相似文献   
994.
Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning. We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to PTA.  相似文献   
995.
羟甲芬太尼(1)是一个强效的镇痛剂和高亲和、高选择性的阿片μ受体激动剂。通过HPLC和1HNMR分析,cis-A-l被确定为由等量的cis-(+)-(3R,4S,2'S)-l和:cis-(—)-(3S,4R,2'R)-1组成的外消旋体,cis-B-l被确定为由等量的cis-(—)-(3R,4S,2'R)-1和cis-(+)-(3S/,4R,2'S)-1组成的外消旋体。  相似文献   
996.
A new method for monitoring neuromuscular function based on measurement of acceleration is presented. The rationale behind the method is Newton's second law, stating that the acceleration is directly proportional to the force. For measurement of acceleration, a piezo-electric ceramic wafer was used. When this piezo electrode was fixed to the thumb, an electrical signal proportional to the acceleration was produced whenever the thumb moved in response to nerve stimulation. The electrical signal was registered and analysed in a Myograph 2000 neuromuscular transmission monitor. In 35 patients anaesthetized with halothane, train-of-four ratios measured with the accelerometer (ACT-TOF) were compared with simultaneous mechanical train-of-four ratios (FDT-TOF). Control ACT-TOF ratios were significantly higher than control FDT-TOF ratios: 116 +/- 12 and 98 +/- 4 (mean +/- s.d.), respectively. In five patients not given any relaxant during the anaesthetic procedure (20-60 min), both responses were remarkably constant. In 30 patients given vecuronium, a close linear relationship was found during recovery between ACT-TOF and FDT-TOF ratios. It is concluded that the method fulfils the basic requirements for a simple and reliable clinical monitoring tool.  相似文献   
997.
A case is reported of fatal acute cerebral oedema occurring in a 15-year-old child suffering diabetic ketoacidosis. He had severe gastro-enteritis, with a weight lose of 8 kg over a period of 8 days (initial weight = 50 kg). He was admitted in a stupor with pH 7.15, 129 mmol.l-1 natraemia, and 31 mmol.l-1 blood glucose concentration. Blood osmolaity was calculated to be 310 mosmol.l-1. He was rehydrated with 416 ml.h-1 normal saline and 416 ml.h-1 of 1.4% sodium bicarbonate. At the same time a total dose of 75 i.u. of ordinary insulin was given. After 2 h, the patient's condition suddenly worsened with unreactive coma, bilateral fixed mydriasis, respiratory pauses, and impairment of haemodynamic state (heart rate 150 b.min-1, blood pressure 80/50 mmHg). The diagnosis of cerebral oedema with severe intracranial hypertension was confirmed by different investigations. Despite ventilatory support and continued intensive care, the patient died a few hours later. It is concluded that some degree of subclinical brain swelling could be common occurrence during diabetic ketoacidosis, present maybe even before the start of treatment. Such cases of cerebral oedema are often reported, but the pathophysiological mechanisms remain unclear. However, unlike this case, rehydration must be moderate (less than 41.m-2.day-1), especially in case of hyponatraemia. Insulin and sodium bicarbonate must be used with care. Early rigorous clinical and biological monitoring is essential. Treatment should aim at a progressive correction of the metabolic disturbances.  相似文献   
998.
Summary Optical isomers (d and l) and racemic compounds (dl) of methamphetamine (MAMP) and amphetamine (AMP), and biologic materials including those substances, could be analyzed by high performance liquid chromatography. Examining the temperature for the analysis, 40°C was the optimal condition in the reproducibility of separated MAMP-isomers. The reproducibility at the temperature did not vary significantly. The measured values of optical isomers were 0.116±0.012, 1.082±0.070 and 8.984±0.136 for the mixing ratios (l/d) of 0.111, 1.000, and 9.000, respectively. The detection limit for both d- and l-isomers was 25 ng.The analytic result of hair specimens from two stimulant abusers by the present method indicates that they contained only d-MAMP and d-AMP, which is believed to have the strongest pharmacologic effect among the optical isomers of MAMP. The coefficient of variation in the analysis of five replicate standards, prepared by adding 1,000 ng each of racemate MAMP and AMP to hair, was less than 4%. The measured value against l/d=1.000 was 1.040±0.040 in MAMP and 0.980±0.030 in AMP. The detection limit for both racemate MAMP and AMP accumulated in hair was 250 ng.The analysis of the optical isomers by our method would contribute to identifying the smuggling routes or the illicit method.  相似文献   
999.
Branhamella catarrhalis is being isolated with increasing frequency from patients with symptoms and signs of respiratory tract infection. Records of 77 patients were reviewed to define the spectrum of respiratory illness and to compare clinical and laboratory features with those of respiratory infection due to Haemophilus influenzae. Both B catarrhalis and H influenzae caused respiratory infection predominantly in elderly males with underlying heart or lung disease. There were no clinical or laboratory features aside from sputum Gram stain and culture which differentiated the two groups. Although fewer than one-half of each group received antibiotics, no patient developed progressive respiratory disease.  相似文献   
1000.
Investigation was carried out in ten children aged between one month and six years, who were anaesthetized by the T-piece circuit. The volume of the reservoir tubing of the T-piece was 250 ml. Ventilation was controlled automatically by oxygen jets which were delivered via an injector attached to the reservoir tubing. The oxygen jets were regulated by an electronically-controlled solenoid valve. The children were ventilated by a tidal volume about 12 ml±kg?1 at a rate of 12-20 per min depending on their age, while the FGF varied between 3 and 6 l min?1 depending on their body weight. The resulting FIO2 ranged between 0.32 and 0.34 which was expected from the oxygen:nitrous oxide mixture (1:2), denoting no mixing of the oxygen jets with the anaesthetic mixture. The PAco2 was ventilation-dependent, and ranged between 4±6-5±3 kPa (35-41 mmHg). The results suggest that automatic jet ventilation facilitates controlled ventilation in children anaesthetized by the T-piece circuit, while maintaining the original simplicity of the T-piece.;  相似文献   
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