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91.
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93.
Magnetic resonance (MR) imaging and computed tomography (CT) were compared in a prospective study of 48 patients for the detection of metastatic mediastinal lymphadenopathy from bronchogenic carcinoma. The images were interpreted by three experienced radiologists using a five-point rating scale, enabling receiver operating characteristic (ROC) analysis. Imaging results were evaluated against "truth" data based on analysis of surgical specimens from mediastinoscopy and thoracotomy. All MR images were cardiac gated to reduce cardiac motion artifacts in the mediastinum. MR and CT both performed well, as indicated by similar areas under the ROC curves of 0.779 +/- 0.039 for MR imaging and 0.781 +/- 0.038 for CT scanning. No strong correlation between nodal size and metastatic involvement could be found for either MR or CT results. As long as nodal size remains the sole criterion in the detection of metastatic mediastinal lymphadenopathy, MR imaging is unlikely to enable better interpretations than CT scanning.  相似文献   
94.
The purpose of the study was to analyse the frequency of sex-chromosome numerical abnormalities in human spermatozoa of infertile men by using a standardized experimental protocol of double target in-situ hybridization (ISH). The experiments were performed on decondensed sperm heads from 15 infertile patients (six cases of unexplained infertility and nine cases of severe oligoasthenoteratozoospermia). Three men of proven fertility were used as controls. The probes employed recognized the centromeric regions of human X chromosome and the long arm of the Y chromosome. In a smaller number of cases, additional experiments of double ISH were performed using centromeric probes for chromosomes 1 and 17. Signal detection was based on protocols of enzymatic cytochemical reactions. A total of 24,508, 24,679 and 42,285 cells were scored in the control, unexplained infertility and severe male factor groups of patients respectively. In all the patients in the ISH efficiency result was approximately 98%. In controls, unexplained infertility and severe male factor patients, the frequency of morphologically normal sperm cells carrying an abnormal chromosome constitution (XX or YY or XY or > 2 sex chromosomes signals) was 0.86, 0.75 and 1.35% respectively. The value of this last group of patients (severe male factor) was significantly higher than in the other two groups of patients (P < 0.008). The same findings were made using the autosomic probes. Our preliminary data support the possibility of an increased risk from paternal origin sex chromosome aneuploidies in children born after intracytoplasmic sperm injection (ICSI). Further investigations of the cytogenetic constitution of spermatozoa from severe male factor patients is warranted.   相似文献   
95.
目的:新山地明给药后,个体间吸收变异相当明显,血药浓度监测管理对减少急性排斥反应发生及降低肝肾毒性十分重要。比较传统的服药前血药浓度(谷值)、服药后2h血药浓度(峰值)监测的临床意义。方法:选择2005-01/2006-04在中山大学附属第一医院行首次同种异体尸肾移植的受者60例,均知情同意。按随机数字表法分成服药前血药浓度组和服药后2h血药浓度组,各30例。两组患者肾移植后前3个月均接受新山地明5~7mg/(kg·d)、霉酚酸酯1.0~1.5g/d和皮质激素三联治疗。采用荧光偏振法测定患者新山地明服药前和服药后2h血药浓度,比较服药前血药浓度与服药后2h血药浓度监测方法预测肾移植急性排斥反应和不良反应(肝毒性、肾毒性)的有效性。结果:60例患者全部进入结果分析。①60例患者在术后3个月内急性排斥反应发生率为13.3%(8/60);不良反应发生率为28.3%(17/60),肝毒性发生率为20.0%(12/60),肾毒性发生率为8.3%(5/60)。②急性排斥反应发生时与非急性排斥反应时服药前血药浓度差异无显著性意义(P=0.08);急性排斥反应发生时服药后2h血药浓度显著低于非急性排斥反应时服药后2h血药浓度(P<0.01)。③发生肝肾毒性1周内的服药前血药浓度与未发生时服药前血药浓度差异无显著性意义(P=0.15);发生肝肾毒性1周内的服药后2h血药浓度显著高于肝肾毒性未发生时(P<0.01)。结论:在肾移植术后早期,与服药前血药浓度相比,服药后2h血药浓度能更敏感的反映急性排斥反应和不良反应的发生。  相似文献   
96.
CCU病房患者应激状态下发生精神异常2例   总被引:2,自引:0,他引:2  
1 临床资料 患者,A,男,81岁,西安市人,农民,主因间断胸闷、气短、双下肢浮肿8mo余,加重10d于1999-12-10急诊收住西京医院心内科CCU病房.入院查体:BP19.3/13.3kPa,神志清,端坐位呼吸,查体合作,口唇紫绀,肝颈反流征(+),双肺布满干湿罗音,以中下肺野中小水泡音为主,心界左扩,心率75次·min-1,律齐,心前区可闻及级收缩期杂音,肝大肋下2指,生理反射存在,病理反射未引出.入院后心电图示:心肌供血不足.胸片提示:心影大,心胸比0.69,肺瘀血.入院诊断:1高血压病级、高心病、急性左心衰.2冠心病.1999-12-12因目睹邻床青年患者病危抢救全过程,于当…  相似文献   
97.
细胞周期素依赖激酶4在颌骨软骨肉瘤的表达及意义   总被引:1,自引:2,他引:1  
目的:分析细胞周期素依赖激酶4(CDK4)在颌骨软骨肉瘤的表达及意义。方法利用免疫组化法检测CDK4在20例颌骨软骨肉瘤、8例骨软骨瘤和8例骨质增生中的表达。结果65.0%(13/20)的软骨肉瘤中CDK4呈阳性表达CDK4表达率随病理学分级的升高呈增高趋势,但未见统计学差异(P〉0.05);CDK4在骨软骨瘤和骨质增生中的阳性表达率分别为12.5%(1/8)和0(0/8),且均与软骨肉瘤有显性  相似文献   
98.
A family showing inheritance of the Inab phenotype   总被引:2,自引:0,他引:2  
An 86-year-old white American woman was found to have a very rare red cell phenotype, the Inab phenotype. Her cells were Cr(a-), Tc(a-b-c-), Dr(a-), Es(a-), WES(a-b-), and IFC-. Unlike the two other Inab phenotype patients, she has no history of protein-losing enteropathy or any similar intestinal disorder. One of her four siblings also has the Inab phenotype, providing the first evidence that this phenotype may be inherited. Serum inhibitions showed that anit-Cra, -TCa, -Dra, -WESb, and -IFC are partially inhibited by sera from three siblings with the common red cell phenotype but not by serum from the Inab phenotype sibling. The serum of the proposita contained an antibody to a high-frequency antigen that showed characteristics of being a Cromer-related antibody.  相似文献   
99.
To examine whether enhanced in vivo proteolysis of von Willebrand factor (vWF) would account for the reported loss of larger multimers in acute thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS), we studied eight patients with acute TTP/HUS whose blood samples were collected into an anticoagulant containing a cocktail of protease inhibitors to impede in vitro proteolysis. In all, enhanced proteolytic degradation of vWF was expressed as a relative decrease in the intact 225-Kd subunit of vWF and a relative increase in the 176-Kd fragment. However, instead of the loss of larger forms of normal multimers reported by other investigators, the plasma of all but one of our patients (whether they had TTP or HUS) contained a set of larger than normal (supranormal) multimers. Hence, although proteolytic fragmentation of vWF was enhanced during acute TTP/HUS, this phenomenon was not associated with the loss of larger multimers. In the five patients who survived the acute disease and underwent plasma exchange (three with HUS and two with chronic relapsing TTP), subunits and fragments returned to normal values, and supranormal multimers were no longer detected in plasma. In conclusion, even though vWF proteolysis is enhanced in acute TTP/HUS, it does not lead to loss of larger multimers.  相似文献   
100.
OBJECTIVE: To evaluate whether treatment with prasterone (dehydroepiandrosterone [DHEA]) would allow the dosage of prednisone (or an equivalent corticosteroid) to be reduced to < or = 7.5 mg/day for 2 months or longer while maintaining stable or reduced disease activity in steroid-dependent women with systemic lupus erythematosus (SLE). METHODS: In a double-blind, randomized trial, 191 female SLE patients receiving prednisone (10-30 mg/day) were treated daily with either placebo, 100 mg of oral prasterone (an adrenal androgen), or 200 mg of oral prasterone for 7-9-months. At monthly intervals, corticosteroid dosages were reduced by algorithm in patients whose SLE Disease Activity Index (SLEDAI) score was stable or improved. Patients for whom a sustained reduction in the dosage of prednisone (< or = 7.5 mg/day) was achieved for at least the last 2 months of the 7-9-month treatment period were classified as responders. RESULTS: Response rates were 41% in the placebo group, 44% in the 100-mg prasterone group, and 55% in the 200-mg group (P = 0.110, 200 mg versus placebo). Among the 137 subjects (45 in the placebo group, 47 in the 100-mg group, and 45 in the 200-mg group) who had active disease at baseline (defined as SLEDAI score >2), 29%, 38%, and 51%, respectively, were responders (P = 0.031 for 200 mg prasterone versus placebo). Acne was the most common adverse event but was generally mild. Clinical and laboratory changes primarily reflected androgenic effects of prasterone. CONCLUSION: Among women with lupus disease activity, reducing the dosage of prednisone to < or = 7.5 mg/day for a sustained period of time while maintaining stabilization or a reduction of disease activity was possible in a significantly greater proportion of patients treated with oral prasterone, 200 mg once daily, compared with patients treated with placebo.  相似文献   
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