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ABSTRACT: A Male rabbit was immunized with rat testicular cytochrome (Cyt) ct and mated with normal, unimmunized females. The matings resulted in abnormal pregnancies: no offspring or stillborn or undersized liveborn offspring weighing 25–30 gm each. Another unusual observation was that fur-pulling behavior, normally exhibited by pregnant female rabbits at the end of the gestational period, was absent in all of these pregnancies. Therefore, immunization of a normal rabbit with testicular cyt ct appeared to interfere with physiological and behavioral aspects of pregnancy in normal female rabbits. The immunological basis of these findings remains to be determined.  相似文献   
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We determined the distribution of DR4 subtypes in 309 DQB1*0302-positive haplotypes found in insulin-dependent diabetes mellitus (IDDM) patients and 70 control haplotypes present only in healthy family members. An increased frequency of DRB1*0401 allele (74.4% vs. 55.7%, P = 0.003) and a decrease of DRB1*0404 allele (23.6% vs. 40.0%, P = 0.0064) was revealed. A further analysis of extended haplotypes demonstrated strong linkages between various B alleles and DRB1*04 subtypes. HLA-B39 was more frequent in DRB1*0404–DQB1*0302-positive IDDM haplotypes compared with control ones (37.0% vs. 14.3%, P = 0.049), suggesting an involvement of the region telomeric to HLA-DRB1 in the susceptibility to IDDM.  相似文献   
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delta-Hexachlorocyclohexane (delta-HCH) interacts with cardiac ryanodine-sensitive Ca2+ channels (RyR2), accounting in part for altered Ca2+ transients and contractility (reported in companion report). Analysis of channel gating kinetics in the presence of delta-HCH also revealed a nonfluctuating membrane current that remained even after RyR2 channels were blocked. We further elucidated the nature of a direct interaction between delta-HCH and biological membranes by measuring ionic currents across planar lipid bilayers made from defined lipids lacking cellular protein using voltage-clamp. Dimethyl sulfoxide, in the presence or absence of 50 microM gamma-HCH (lindane) or delta-HCH, produced negligible steady-state current with symmetric 100 mM CsCl in the range of +/-50 mV. However, the addition of 50 microM Ca2+ to the bilayer chamber in the presence of delta-HCH induced a profound increase in ionic permeability that was not seen in the presence of gamma-HCH or dimethyl sulfoxide control. Significantly, the permeability increase 1) was proportional with increasing Ca2+ to approximately 600 microM and saturated between 1 and 2 mM Ca2+ regardless of holding potential, 2) occurred only when delta-HCH and Ca2+ were added to the same side of the membrane, and 3) was independent of the order of addition or of the side of the membrane to which delta-HCH and Ca2+ was added. The Ca2+-dependent current produced by delta-HCH was highly selective for monovalent cations (K+ > Cs+ > Na+), with negligible conductance for Ca2+ or Cl-. In symmetric 100 mM K+, the conductance induced with 50 microM concentration each of delta-HCH and Ca2+ was 4.25 pA/mV. The results show that delta-HCH increases the ionic permeability of phospholipid membranes by two distinct Ca2+-dependent mechanisms: one mediated through RyR and the other mediated by a unique ionophore activity.  相似文献   
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目的:研究国产美罗培南用于抗感染治疗的临床疗效和安全性.方法:将30例中、重度急性细菌性感染患者按随机对照平行法分成2组,治疗组14例,给予美罗培南0.5g,q8h,静脉滴注;对照组16例,给予泰能(亚胺培南/西司他丁)1.0g,q8h,静脉滴注.两药疗程均为7~10d.结果:两组的临床痊愈率均为50%;临床有效率治疗组和对照组分别为85.7%和87.5%;细菌清除率分别为84.6%和85.7%;不良反应发生率分别为14.3%和18.8%.以上指标两组差异均无显著性(P>0.05).结论:国产新药美罗培南用于抗感染治疗安全有效.  相似文献   
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The aim of this trial was to compare the efficacy of combinationantithrombotic therapy with a prostacyclin-sparing aspirin plusanticoagulation versus conventional aspirin plus anticoagulation,when added to antianginal therapy, in patients with unstableangina or non-Q wave myocardial infarction already being treatedwith aspirin. In a double-blind (for the aspirin) study, 144prior aspirin users were randomized; 72 patients received controiled-release,prostacyclin-sparing aspirin 75 mg daily plus anticoagulation(intravenous heparin followed by warfarin to maintain the internationalnormalized ratio at 2–3), and 72 patients received conventionalaspirin 75 mg daily plus the same anticoagulation. Controlled-releaseaspirin was formulated to preserve endothelial cell prostacyclinsynthesis. Trial therapy was begun by 13.2 ± 12.3 h ofqualifying pain, and continued for 12 weeks. The frequency of recurrent angina with electrocardiographicchanges, myocardial infarction, or death, was analysed by intentionto treat. At 12 weeks, events were  相似文献   
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目的:探讨肺隔离症的手术治疗方法和效果。方法回顾性分析该院在2003年3月-2014年3月间收治的17例肺隔离症患者的临床资料。结果①该组17例患者中,术前确诊者13例;术中确诊4例;②采用肺叶切除术对患者进行治疗,全部痊愈,无1例死亡;③术后并发症的发生率为17.64豫(3/17),经对症处理后均缓解;④术后随访6个月~10年,复查X线胸片和CT,结果显示均正常。结论肺隔离症是临床中比较少见的肺先天性畸形,临床表现无特异性,易发生误诊和漏诊,临床中以肺叶切除术治疗为主,效果良好,值得临床推广。  相似文献   
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A familial study of four cases with hypobetalipoproteinemia is reported. Three members are heterozygous and one is homozygous. This congenital fat malabsorption in homozygous state is commonly associated with an absence of serum apoprotein B and LDL. Neuromuscular and ophthalmological signs are absent in this case. The major role of upper digestive endoscopy in the diagnostic procedure is emphasized. Histochemical and immunoenzymatic stains of enterocytes and intestinal organ culture show defective synthesis apo B in the homozygous patient. Studies of DNA polymorphism in the homozygous patient have shown that the apo B gene doesn't certain major insertions or deletions. These results are discussed.  相似文献   
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