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911.
912.
Absence of antibody production in patients treated with botulinum A toxin   总被引:4,自引:0,他引:4  
To test the possibility of the formation of an antibody to botulinum A toxin after multiple injections of this potent neurotoxin, we collected serum samples from 28 patients who received 57 doses. These injections over a nine-month period with as much as 50 units per injection formed no detectable antibody.  相似文献   
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Vascular disturbance of the anterior visual pathways characterized by monocular visual experiences are sometimes caused by migraine. Retinal or ophthalmic migraine, a variant of complicated migraine, is distinctly rare. Two cases of female patients with ophthalmic migraine are reported. The relationships between the use of oral contraceptives and pregnancy are discussed.  相似文献   
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The bed nucleus of the stria terminalis (BNST) and its adrenergic input are key components in stress-induced reinstatement and maintenance of drug use. Intra-BNST injections of either beta-adrenergic receptor (beta-AR) antagonists or alpha2-adrenergic receptor (alpha2-AR) agonists can inhibit footshock-induced reinstatement and maintenance of cocaine- and morphine-seeking. Using electrophysiological recording methods in an in vitro slice preparation from C57/Bl6j adult male mouse BNST, we have examined the effects of adrenergic receptor activation on excitatory synaptic transmission in the lateral dorsal supracommissural BNST (dBNST) and subcommissural BNST (vBNST). Alpha2-AR activation via UK-14,304 (10 microM) results in a decrease in excitatory transmission in both dBNST and vBNST, an effect predominantly dependent upon the alpha2A-AR subtype. Beta-AR activation via isoproterenol (1 microM) results in an increase in excitatory transmission in dBNST, but not in vBNST. Consistent with the work with receptor subtype specific agonists, application of the endogenous ligand norepinephrine (NE, 100 microM) elicits two distinct effects on glutamatergic transmission. In dBNST, NE elicits an increase in transmission (62% of dBNST NE experiments) or a decrease in transmission (38% of dBNST NE experiments). In vBNST, NE elicits a decrease in transmission in 100% of the experiments. In dBNST, the NE-induced increase in synaptic transmission is blocked by beta1/beta2- and beta2-, but not beta1-specific antagonists. In addition, this increase is also reduced by the alpha2-AR antagonist yohimbine and is absent in the alpha2A-AR knockout mouse. In vBNST, the NE-induced decrease in synaptic transmission is markedly reduced in the alpha2A-AR knockout mouse. Further experiments demonstrate that the actions of NE on glutamatergic transmission can be correlated with beta-AR function.  相似文献   
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OBJECTIVES: To compare the effect of conjugated equine estrogens (CEE) and raloxifene on lipid profile and hemostasis. MATERIALS AND METHODS: A double-blind, randomized and parallel study was performed with 90 healthy postmenopausal women, aged 54 +/- 5 years, divided into three groups and submitted to daily therapy with either CEE 0.625 mg, raloxifene 60 mg or placebo for 4 months. The lipid profile, coagulation and fibrinolytic factors were analyzed. RESULTS: CEE increased the levels of high density lipoprotein cholesterol (HDL-C) from 49.0 to 56.8 mg/dl (p < 0.001), very low density lipoprotein cholesterol (VLDL-C) from 17.2 to 22.3 mg/dl (p < 0.001), and triglycerides from 86.0 to 111.7 mg/dl (p < 0.001), and decreased the levels of low density lipoprotein cholesterol (LDL-C) from 121.0 to 106.5 mg/dl (p < 0.001). The only significant effect of raloxifene was an increase in the levels of HDL-C from 46.0 to 47.8 mg/dl (p = 0.019). There was no significant reduction in LDL-C, from 115.5 to 110.2 mg/dl (p = 0.06), VLDL-C, from 21.7 to 20.0 mg/dl (p = 0.201), and triglycerides, from 108 to 100 mg/dl (p = 0.201). CEE decreased the levels of fibrinogen, from 370.5 to 326.8 g/l (p = 0.039) and the levels of antithrombin III, from 99.5 to 93.2% (p < 0.001). Raloxifene decreased the levels of fibrinogen, from 354.7 to 302.0 g/l (p = 0.009) and the levels of antithrombin III, from 102.4 to 98.5% (p = 0.039). CEE increased levels of protein C from 103.7 to 115.3 mg/l (p < 0.001) and raloxifene did not change the levels of protein C (107.9 to 105.1 mg/l; p = 0.158). CEE decreased the antigen levels of tissue plasminogen activator (t-PA) from 8.8 to 6.8 U/ml (p < 0.001), and of plasminogen activator inhibitor (PAI-1) from 30.8 to 21.6 U/ml (p < 0.010), whereas raloxifene had no significant effect on either t-PA, from 9.6 to 9.2 U/ml (p = 0.235) or PAI-1 antigen levels, from 32.1 to 30.4 U/ml (p = 0.538). CONCLUSION Both CEE and raloxifene exert significant effects on the lipid and coagulation profile. CEE had a more significant effect on fibrinolysis than raloxifene. These effects may have a significant impact on the cardiovascular risk that needs to be confirmed in larger studies.  相似文献   
920.
Gallibacterium anatis (previously named Pasteurella haemolytica-like) is considered a normal inhabitant of genital and upper respiratory tracts of healthy chickens, but it is also associated with different pathological conditions. Secreted metalloproteases from field and reference G. anatis cultures were obtained by methanol precipitation and were characterized. Proteins of molecular mass higher than 100 kDa showing proteolytic activity were observed in 10% polyacrylamide gels copolymerized with 1% bovine casein. They were active at alkaline pH, and inhibited by ethylenediamine tetraacetic acid. Their activity was stable at 50 degrees C, but partially inhibited at 60 degrees C, and totally inhibited at higher temperatures. Secreted proteins were able to degrade chicken IgG after 24 h of incubation, and cross-reacted with a polyclonal antibody against purified protease from Actinobacillus pleuropneumoniae. Secreted metalloproteases could play a role in infections caused by G. anatis.  相似文献   
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