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971.
972.
973.
W M Dell 《Journal of the American Optometric Association》1985,56(2):113-119
The pseudo-exfoliation syndrome is characterized by the deposition of light gray or white dandruff-like flakes on various intraocular structures, most clinically apparent on the anterior lens capsule and pupillary margin but more significantly on the trabecular meshwork and ciliary processes. Its prevalence in various populations and relationship to age, sex, geography, heredity, and particularly to glaucoma have been the subject of numerous studies. Its prevalence is generally variable (depending on the subject population) and ranges from 1 to 8 percent, increasing with age. It is positively associated with higher levels of intraocular pressure and open-angle glaucoma. Although further carefully-controlled studies of prevalence and their relationship with glaucoma are desirable, patients with evidence of pseudo-exfoliation should be treated as glaucoma suspects. 相似文献
974.
Topology and order of formation of interchain disulfide bonds in von Willebrand factor 总被引:9,自引:3,他引:6
Interchain disulfide bonds between the subunits in von Willebrand factor (vWf) dimers and in vWf multimers have been studied using some unique features of the cultured human umbilical vein endothelial cell system. Ammonium chloride inhibition of multimerization of vWf allowed selective examination of vWf dimeric molecules, and monoclonal antibody against the vWf propolypeptide was used to separate pro-vWf dimers from mature dimers. After cleavage of dimers and multimers with Staphylococcus aureus V-8 protease, the location of interchain disulfide bonds in amino (N)-terminal or carboxyl (C)-terminal fragments was determined by gel electrophoresis under reduced and nonreduced conditions. The first interchain disulfide bonds formed during dimerization are in the C-terminal region of the subunits, whereas interdimer disulfide bonds are located in the N-terminal portion. These data confirm recent electron microscopic projections of disulfide bond locations and provide support to the hypothetical role of the propolypeptide in the multimerization process. 相似文献
975.
976.
Reynolds HN Sheinfeld G Chang J Tabatabai A Simmons D 《Telemedicine journal and e-health》2011,17(9):746-749
Disaster plans, during the actual disaster, often do not function as conceived and designed. Disaster or emergency situations may not present as anticipated in planning sessions confounding the intent of disaster planners. Systems that are created and shelved awaiting the disaster may be dysfunctional when needed due to problems such as failed batteries, forgotten training, misplaced equipment, the retraining curve, or software that has not been updated. We report here the smooth and seamless transition to disaster mode from a system in daily use and therefore operational when needed. 相似文献
977.
Hugo A. Tejeda Luis A. Natividad James E. Orfila Oscar V. Torres Laura E. O’Dell 《Psychopharmacology》2012,224(2):289-301
Rationale
Mechanisms that mediate age differences during nicotine withdrawal are unclear.Objective
This study compared kappa-opioid receptor (KOR) activation in na?ve and nicotine-treated adolescent and adult rats using behavioral and neurochemical approaches to study withdrawal.Methods
The behavioral models used to assess withdrawal included conditioned place and elevated plus maze procedures. Deficits in dopamine transmission in the nucleus accumbens (NAcc) were examined using microdialysis procedures. Lastly, the effects of KOR stimulation and blockade on physical signs produced upon removal of nicotine were examined in adults.Results
Nicotine-treated adults displayed a robust aversion to an environment paired with a KOR agonist versus na?ve adults. Neither of the adolescent groups displayed a place aversion. KOR activation produced an increase in anxiety-like behavior that was highest in nicotine-treated adults versus all other groups. KOR activation produced a decrease in NAcc dopamine that was largest in nicotine-treated adults versus all other groups. Lastly, KOR activation facilitated physical signs of withdrawal upon removal of nicotine and KOR blockade reduced this effect.Conclusion
Chronic nicotine enhanced the affective, anxiogenic, and neurochemical effects produced by KOR activation in adult rats. Our data suggest that chronic nicotine elicits an increase in KOR function, and this may contribute to nicotine withdrawal since KOR activation facilitated and KOR blockade prevented withdrawal signs upon removal of nicotine. Given that chronic nicotine facilitated the neurochemical effects of KOR agonists in adults but not in adolescents, it is suggested that KOR regulation of mesolimbic dopamine may contribute to age differences in nicotine withdrawal. 相似文献978.
V Gambaro P Minghetti S Arnoldi ML Colombo L Dellʼacqua A Casiraghi K Guerrini F Farè G Roda 《Planta medica》2012,78(12):1395-1398
In this paper, we report a case of misidentification of medicinal plants involving dried petals of Papaver rhoeas (red poppy) contaminated with Papaver bracteatum (scarlet poppy) petals. Preliminary TLC analysis indicated the presence of thebaine either in the fluid extracts or in the petals. It was therefore necessary to carry out an accurate botanic examination of the plant material, which revealed contamination of the red poppy petals with scarlet poppy petals. Moreover, to confirm the adulteration, we developed and validated an efficient, reversed-phase ion pair HPLC method for determination of the alkaloids specific for the Papaver species. Six petal batches and five commercial fluid extracts were analyzed. Only one petal batch from Iran contained thebaine and its analogue oripavine while the alkaloids typical for the Papaver bracteatum species were identified in all fluid extracts, meaning that they were all prepared with contaminated petals. 相似文献
979.
Background
To control avian coccidiosis with drug-independent strategy effectively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY) was prepared and its ability to protect against Eimeria tenella infection was evaluated.Methods
Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophilized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oocysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed.Results
The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG), reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P<0.05). No significant difference was observed at dosage ≥ 0.5% and 1.0% when BWG and caecal lesion were compared with the sodium salinomycin control group, respectively (P>0.05).Conclusion
Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis. 相似文献980.