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101.
J. M. Vega M. Blanca J. J. Garcia M. J. Carmona A. Miranda M. Perez-Estrada S. Fernandez J. M. Acebes S. Terrados 《Allergy》1994,49(5):317-322
A large group of patients with suspected allergic reactions to (β-lactam antibiotics was evaluated. A detailed clinical history, together with skin tests, RAST (radioallergosorbent test), and controlled challenge tests, was used to establish whether patients allergic to β-lactam antibiotics had selective immediate allergic responses to amoxicillin (AX) or were cross-reacting with other penicillin derivatives. Skin tests were performed with benzylpenicilloyl-poly-L-lysine (BPO-PLL), benzylpenicilloate, benzylpenicillin (PG), ampicillin (AMP), and AX. RAST for BPO-PLL and AX-PLL was done. When both skin test and RAST for BPO were negative, single-blind, placebo-controlled challenge tests were done to ensure tolerance of PG or sensitivity to AX. A total of 177 patients were diagnosed as allergic to β-lactam antibiotics. We selected the 54 (30.5%) cases of immediate AX allergy with good tolerance of PG. Anaphylaxis was seen in 37 patients (69%), the other 17 (31%) having urticaria and/or angioedema. All the patients were skin test negative to BPO; 49 of 51 (96%) were also negative to MDM, and 44 of 46 (96%) to PG. Skin tests with AX were positive in 34 (63%) patients. RAST was positive for AX in 22 patients (41%) and to BPO in just 5 (9%). None of the sera with negative RAST for AX were positive to BPO. Challenge tests with AX were performed in 23 subjects (43%) to establish the diagnosis of immediate allergic reaction to AX, and in 15 cases (28%) both skin test and RAST for AX were negative. PG was well tolerated by all 54 patients. We describe the largest group of AX-allergic patients who have tolerated PG reported so far. Diagnosis of these patients can be achieved only if specific AX-related reagents are employed. Further studies are necessary to determine the exact extent of this problem and to improve the efficacy of diagnostic methods. 相似文献
102.
Controlled administration of penicillin to patients with a positive history but negative skin and specific serum IgE tests 总被引:3,自引:0,他引:3
M. J. Torres C. Mayorga L. Leyva A. E. Guzman J. A. Cornejo-García C. Juarez M. Blanca 《Clinical and experimental allergy》2002,32(2):270-276
BACKGROUND: Although subjects with a positive history of immediate allergy to penicillin and negative skin test are traditionally considered to tolerate penicillin, current evidence indicates that they may develop an immediate reaction despite negative skin and serum specific IgE tests. It is thought that these patients require additional tests to confirm the diagnosis. OBJECTIVE: To assess in a large group of patients with a history of immediate allergy to penicillins but with both skin test and CAP-FEIA-negative to classical and side chain penicillin determinants, the role of controlled administration of betalactams as a diagnostic test. METHODS: A group of 330 patients with a history of immediate allergic reactions to penicillins was studied by two evaluators from the same allergy unit using the following protocol: skin tests with major and minor determinants of benzylpenicillin (benzylpenicilloyl-poly l-lysine and minor determinant mixture), amoxicillin and ampicillin, and determination of specific IgE antibodies to penicillins, by CAP-FEIA, in serum. If both tests proved negative, a controlled administration of the drug was then carried out. RESULTS: A total of 89 (27%) patients were skin test and CAP-FEIA-negative and therefore required controlled administration of the drug. Of these, 49 developed an immediate response and were therefore considered allergic, and the remainder had good tolerance after administration of both benzylpenicillin and amoxicillin. The clinical characteristics of this group were similar to the other allergic patients who were skin test or CAP-FEIA-positive, except that they were younger (P < 0.01). Twenty-two (45%) developed a response to benzylpenicillin and 27 (55%) had a selective response to amoxicillin. Although all reactions appeared within 1 h, a positive correlation was found between the dose inducing the response and the time elapsed from drug administration, for both benzylpenicillin and amoxicillin (P < 0.001). CONCLUSION: These data indicate that an important number of subjects are not correctly identified if only skin tests and/or CAP-FEIA are used and that this is particularly relevant for side chain-specific reactions and younger subjects. This suggests that new diagnostic tests are required so as to limit the use of controlled administration. 相似文献
103.
Varicocele: effect on sperm functions 总被引:2,自引:0,他引:2
Despite the numerous studies published over the past decade, the role of varicocele in male infertility is still controversial. Although more frequent in infertile men, its influence on sperm production or function has not, as yet, been determined. Moreover, the exact mechanism of varicocele action is not clear. We have surveyed the literature, the correlation of varicocele to sperm parameters and to sperm function tests, such as binding capacity, hypo-osmotic swelling test, presence of reactive oxygen species, and in particular, the correlation to fertility potential. Almost every subject examined had contradictory results. Larger control studies may possibly elucidate and clarify the cases in which varicocele is associated to sperm function, and where treatment may improve fertility. 相似文献
104.
In the event of smallpox bioterrorism, widespread vaccination may be required. Vaccinia immune globulin (VIG) has been used to treat complications from the smallpox vaccine. While the potency of VIG was defined by its ability to neutralize intracellular mature virus, a second form of vaccinia called the extracellular enveloped virus (EEV) is critical for virus spread in the host. The B5R-protein is one of many EEV-specific proteins. Immunoprecipitation and ELISA revealed that VIG recognizes the B5R-protein. An EEV plaque-reduction assay using a recombinant vaccinia that lacks the majority of the extracellular domain of B5R showed that the ability of VIG to neutralize EEV is principally directed at B5R. In addition, absorbing out the anti-B5R antibody present in VIG through the addition of recombinant B5R protein abrogated VIG's ability to significantly neutralize wild-type EEV. This work demonstrates the prominent role of B5R as a target of EEV-neutralizing activity of human antibodies. 相似文献
105.
目的:修订Griffith精神发育量表(0~7岁),并建立适合中国国情的常模。方法:采用对城市级别、年龄、性别、父亲职业等因素按比例分层随机抽样的方法,从山西省十二个城市共抽取了2022例0~7岁儿童,样本人群中上述几个因素的构成与山西省人口资料相吻合,由经过专门培训的测试员对抽样点当地的每个儿童进行单独测试,并填写测查量表。结果:年龄分组样本和总样本各分测验以及总发育商的均数都在100上下浮动,总发育商服从正态分布;项目分析显示,各分测验及总量表平均难度在0.5左右,鉴别指数0.62~0.78;对原量表个别项目的排序进行调整;测试者信度0.953,重测信度0.798~0.948,各分测验之间及分测验与总发育商之间相关系数在0.481~0.854之间,探索性因素分析的结果得到思维推理、知觉组织、意动因子三个因素,解释方差比率总计79.8%。结论:引进和修订后的Griffith量表具有较好的信度和效度,可用于评定儿童的智力水平,可以在山西省应用。 相似文献
106.
A variety of adverse reactions to local anesthetics has been described, some of which are thought to be allergic. Different protocols of prick and intradermal skin tests as well as subcutaneous challenge tests are used to select a local anesthetic which can safely be used. Their long-term effectiveness has not yet been assessed. Twenty-eight patients with a history of adverse reaction to local anesthetics were evaluated over a 3-year period. Loss of consciousness occurred in eight patients, skin reaction in nine, and vagal symptoms in eight. Various reactions were recorded in the remaining three patients. Rapid spontaneous recovery was the rule, suggesting that immediate allergic reaction and, in particular, anaphylactic reaction were unlikely. Investigation allowed the selection of a tolerated anesthetic in all cases. Reexposure occurred in 19 patients 16–50 months after evaluation and 6.8 ± 5.5 years after the first reaction. No patient presented a second reaction. In conclusion, adverse reactions to local anesthetics seem to be, in most cases, not allergic in nature. Evaluation protocols are effective in selecting an agent susceptible to tolerance, but are time consuming. However, they probably contribute to an important reassurance effect that is likely to increase tolerance to subsequent local anesthetic administration. Simplification of the protocols and better patient selection are proposed. 相似文献
107.
目的 比较分析单纯急性戊型肝炎与重叠感染患者的肝功能指标和临床特点.方法 以40例单纯急性戊型肝炎为对照,回顾性分析了122例重叠感染戊型肝炎患者的肝功能指标、临床资料.结果 单纯戊肝组、甲戊重叠感染组、乙戊重叠感染组,三组之间ALT、AST、TBIL、DBIL差异均无统计学意义(P0.05),急性戊肝组与乙戊重叠感染组,甲戊重叠感染组与乙戊重叠感染组的白蛋白、球蛋白有统计学差异(P<0.01);甲戊重叠感染、乙戊重叠感染与单纯戊肝相比较临床合并症多、并发症重.结论 戊型肝炎重叠感染,特别是乙戊重叠感染患者,要加强临床监测,提高早期预防并发症的意识,以降低病死率. 相似文献
108.
大鼠再生肝对二乙基亚硝胺启动作用的敏感性 总被引:2,自引:0,他引:2
目的比较再生肝和正常肝对二乙基亚硝胺(DEN)启动作用的敏感性。方法以2/3肝叶切除后8周末的大鼠为实验组,正常大鼠为对照组,作如下比较:肝重、常规组织学检查及3H-TdR掺入试验;用修改的Solt-Farber模型,通过对GGT阳性癌前病灶的体视学测量,观察肝脏对DEN的启动效应;在体内和体外(无血清原代培养肝细胞)经DEN攻击后,以核酸原位缺口标记方法观察肝细胞DNA的损伤程度。结果2/3肝叶切除后8周末的实验组肝脏的修复过程已完成,未见肝细胞继续增生的表现;经DEN攻击后,实验组肝癌前病灶在数密度和体积密度上都显著高于对照组;无论在体内或体外接受DEN攻击后,实验组肝细胞DNA的损伤程度都显著大于对照组。结论即使再生过程已经完成,再生肝仍比正常肝具有较高的致癌敏感性,这与再生肝肝细胞在DEN攻击后其DNA损伤较重相关。 相似文献
109.
目的 比较分析单纯急性戊型肝炎与重叠感染患者的肝功能指标和临床特点.方法 以40例单纯急性戊型肝炎为对照,回顾性分析了122例重叠感染戊型肝炎患者的肝功能指标、临床资料.结果 单纯戊肝组、甲戊重叠感染组、乙戊重叠感染组,三组之间ALT、AST、TBIL、DBIL差异均无统计学意义(P0.05),急性戊肝组与乙戊重叠感染组,甲戊重叠感染组与乙戊重叠感染组的白蛋白、球蛋白有统计学差异(P<0.01);甲戊重叠感染、乙戊重叠感染与单纯戊肝相比较临床合并症多、并发症重.结论 戊型肝炎重叠感染,特别是乙戊重叠感染患者,要加强临床监测,提高早期预防并发症的意识,以降低病死率. 相似文献
110.
目的:观察肝门阻断(HVO)及再开放(HVR)后胰腺内外分泌功能的改变。方法:选择健康日本大耳白兔25只,体重2.3-3.0 kg,分别于HVO前、HVO 10、20 min及HVR后(10、30、60、120 min)不同时点取血,并在HVO前、HVO 20 min、HVR后120 min 3个时点取胰腺组织,电镜下观察其超微结构的变化。结果:HVO时,血浆葡萄糖、胰岛素水平及一氧化氮代谢产物(NO2-/NO3-)含量均明显低于阻断前,胰高血糖素/胰岛素及丙二醛(MDA)浓度显著高于阻断前(P<0.05或P<0.01),并随阻断时间延长而加重;血浆淀粉酶、脂肪酶、游离脂肪酸水平则无明显差异(P>0.05);胰岛细胞的线粒体肿胀、粗面内质网扩张,细胞核形态、结构基本正常,而胰腺腺泡细胞变化则不明显。HVR后上述差异逐渐不明显,至120min才接近阻断前水平。结论:急性肝门阻断和再开放对胰腺内分泌功能有较大的影响。 相似文献