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81.
加热法人心肌钙蛋白T的提取与纯化   总被引:4,自引:2,他引:2  
目的以加热法从人左心室肌组织中提取并纯化心肌肌钙蛋白T(CTnT)。方法取新鲜人左心室肌经捣碎、淬取、加热、透析后提取CTnT,以DEAE52柱层析纯化。结果经SDS-PAGE凝胶电泳初步鉴定,每100g左心室肌经此法可得11.79mgCTnT纯品,纯化后的cTnT为单一条带,分子量为37KD。结论本法提取CTnT步骤简单,纯度尚可,可做抗原使用。  相似文献   
82.
1993年7月~1998年1月为103例(106只眼)难治性青光眼患者施行国产房水引流物(HAD)置入术。术后平均随访328月。术后1年时平均眼压22±1.4kPa。术后1~5年的手术成功率分别为838%,804%,771%,710%及643%。术中联合应用丝裂霉素C的病例,其术后1年时的成功率为895%。术后常见的并发症有持续性浅前房,局限性脉络膜脱离及眼压升高等。认为HAD可用于治疗难治性青光眼。  相似文献   
83.
Before the introduction of modern ophthalmic surgical technology following World War II, cataract extraction was easier and safer to perform if the cataract was far advanced (mature) and both eyes were involved. The surgeon was constrained from early surgery by the frequency of severe complications, the long convalescent period, and the distortions of aphakic glasses. Now it is easier to perform phacoemulsification and implant lenses in the early stages of cataract formation when the nucleus is soft and the posterior lens capsule has not been weakened with age. Also, modern small-incision extracapsular cataract extraction has a low rate of complications and a short convalescent period. It is feasible to extract a clear lens or one with minimal opacifications and have a grateful patient. The surgeon is capable of improving the refractive state of the eye by selecting the power of the intraocular lens. These facts have led to instances where cataracts have been extracted that were responsible for minimal or no symptoms. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
84.
对白内障术后3个月裸眼视力≥0.8者466例,包括术后第一天裸眼视力≥0.8者199例进行统计分析,发现在同等条件下,3.5mm小切口PHACO术优于6mm切口PHACO术,更优于ECCE术;术前视力与术后裸眼视力正相关,患者年龄与术后视力负相关。  相似文献   
85.
超声乳化白内障手术中小瞳孔的处理   总被引:4,自引:0,他引:4  
朱晓青  宋旭东  施玉英 《眼科》1999,8(1):12-14
探讨超声乳化白内障手术中处理小瞳孔的方式。采用粘弹剂或非切开方式的瞳孔成形术扩大瞳孔。20例小瞳孔术中均得到扩大,且成功地行前囊连续环形撕囊和超声乳化手术。采用粘弹剂或非切开方式的瞳孔成形术扩大瞳孔,是有效的经济的手术方法,几乎适用于所有的小瞳孔白内障手术。  相似文献   
86.
高度近视白内障小切口超声乳化摘除术   总被引:14,自引:0,他引:14  
目的:探讨经透明角膜隧道对高度近视白内障患者行超声乳化摘除术的可行性及手术技巧。方法:对216例高度近视合并白内障患者,经角膜缘隧道切口行超声乳化吸出,并植入软性或硬性人工晶体。对超声乳化能量、时间、负压及术后视力、散光及并发症进行观察。结果:采用较低能量、中度真空压力及中低档流速行超声乳化吸出,术后视力≥0.8者143例,≥0.5者49例。术前近视力≥0.8者,术后远视力常较佳。术前及术后散光3.0mm切口组无统计学差异,5.5mm切口组有统计学差异。未见明显严重并发症。结论:透明角膜超声乳化联合软性或硬性人工晶体植入,是高度近视白内障较理想的手术方式。  相似文献   
87.
目的:探讨白内障超乳化摘除,睫状体平坦部下班体切割及人工晶体囊袋内植入联合手术的疗效及安全性。方法:对玻璃体视网膜病普合并白内障18例(18眼)施行该联合手术。其中糖尿病性视网膜病变,玻璃体出血伴白内障10例;视网膜分枝静脉阻塞,玻璃体出血伴白内障4例;视网膜静脉周围炎,玻璃体出血伴白内障3例及特发性视网膜1例,术后随访2~13个月(平均9月)。结果:术后视力均有不同程度提高。12眼(67%)术后  相似文献   
88.
Objective To determine the role of cerebral vasoconstriction in the delayed hypoperfusion phase in comatose patients after cardiac arrest.Design Prospective study.Setting Medical intensive care unit in a university hospital.Patients 10 comatose patients (Glasgow Coma Score 6) successfully resuscitated from a cardiac arrest occurring outside the hospital.Measurements We measured the pulsatility index (PI) and mean blood flow velocity (MFV) of the middle cerebral artery, the cerebral oxygen extraction ratio and jugular bulb levels of endothelin, nitrate, and cGMP during the first 24 h after cardiac arrest.Results The PI decreased significantly from 1.86±1.02 to 1.05±0.22 (p=0.03). The MFV increased significantly from 29±10 to 62±25 cm/s (p=0.003). Cerebral oxygen extraction ratio decreased also from 0.39±0.13 to 0.24±0.11 (p=0.015). Endothelin levels were high but did not change during the study period. Nitrate levels varied widely and showed a slight but significant decrease from 37.1 mol/l (median; 25th–75th percentiles: 26.8–61.6) to 31.3 mol/l (22.1–39.6) (p=0.04). Cyclic guanosine monophosphate levels increased significantly from 2.95 nmol/l (median; 25th–75th percentiles: 2.48–5.43) to 7.5 nmol/l (6.2–14.0) (p=0.02).Conclusions We found evidence of increased cerebrovascular resistance during the first 24 h after cardiac arrest with persistent high endothelin levels, gradually decreasing nitrate levels, and gradually increasing cGMP levels. This suggests that active cerebral vasoconstriction due to an imbalance between local vasodilators and vasoconstrictors plays a role in the delayed hypoperfusion phase.  相似文献   
89.
Objectives To compare the effects of inhaled nitric oxide and aerosolized prostacyclin (PGI2) on hemodynamics and gas exchange as well as on the indocyanine-green plasma disappearance rate and gastric intramucosal pH in patients with septic shock.Design Prospective, randomized, interventional clinical study.Setting Intensive care unit in a university hospital.Patients Sixteen patients with pulmonary hypertension and septic shock according to the criteria of the ACCP/SCCM consensus conference all requiring norepinephrine and/or epinephrine to maintain mean arterial blood pressure above 65 mmHg.Methods and interventions Patients were randomly assigned to receive either nitric oxide or aerosolized prostacyclin. Nitric oxide was inhaled using a commercially available delivery system, prostacyclin was administered with a modified ultrasound nebulizer. Both nitric oxide and prostacyclin were incrementally adjusted to obtain a 15% decrease of mean pulmonary artery pressure. Hemodynamics and gas exchange as well as indocyaninegreen plasma disappearance rate and gastric intramucosal pH were determined at baseline after 90 min in steady state, after 90 min of nitric oxide inhalation or prostacyclin aerosol administration had elapsed in stable conditions, and after 90 min in stable conditions after nitric oxide or prostacyclin with-drawal.Results Both inhaled nitric oxide and aerosolized prostacyclin selectively reduced the mean pulmonary artery pressure from 35±4, 30±4 mmHg (p<0.05) and 34±4 to 30±3 mmHg (p<0.05) respectively; after removal of nitric oxide and prostacyclin, the mean pulmonary artery pressure returned to the baseline values. Systemic hemodynamics remained unaltered during the vasodilator treatment. While the mean PaO2 was not significantly influenced, it increased in 4/8 of the NO- and 3/8 of the PGI2 — treated patients. Neither of the drugs influenced indocyanine-green plasma disappearance rate, but prostacyclin — unlike nitric oxide — significantly increased gastric intramucosal pH (from 7.26±0.07 to 7.30±0.05,p<0.05) which remained elevated in four of these patients after prostacyclin removal, and decreased the arterial-gastric mucosal pressure of carbon dioxide gap from 19±6 to 15±4 mmHg (p<0.05).Conclusions Our data suggest that aerosolized prostacyclin — unlike nitric oxide — has similar beneficial effects on splanchnic perfusion and oxygenation as intravenous prostacyclin without detrimental effects on systemic hemodynamics. The different effects of prostacyclin and nitric oxide might be explained by the longer half-life of prostacyclin associated with a certain spillover into the systemic circulation.Presented in part at the Masterclass Symposium Sepsis in the ICU, Maastricht, June 27–29, 1995  相似文献   
90.
A new flow cytometric method was developed to detect apoptotic cells with fragmented DNA and to determine cell cycle distribution of viable cells, in the same sample, by propidium iodide staining. Apoptosis, in HT58 human B lymphoma cells, was induced by etoposide and/or by staurosporine. Using appropriate alkaline solutions (between 1-10 mN NaOH in 150 mM saline) followed by neutralization with buffer solution, the fragmented DNA can be extracted quantitatively from ethanol fixed cells. Further, good resolution of the cell cycle distribution can be obtained in unimpaired cells without RNase treatment. Furthermore, unlike the widely used hypotonic-detergent extraction of unfixed cells, the suggested extraction method can prevent drug-induced disintegration of dead cells when karyorrhexis occurs. This work was supported by Hungarian National Research Foundation (OTKA I/352 and OTKA II/2622).  相似文献   
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