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941.
The effective dosage of a chewable formulation of ivermectin was determined in 35 young dogs with induced infections of Ancylostoma caninum and Uncinaria stenocephala. Dogs were inoculated with these parasites and held until the infections were patent. Within each of 7 replicates, dogs were allocated randomly to 1 of 5 treatment groups: vehicle control, or ivermectin at 6, 12, 18, or 24 micrograms/kg. Chewable treatments were tailored to body weight. Seven or 8 days after treatment, parasites were recovered using standard techniques. All 7 controls had adult A. caninum (geometric mean = 35.5) and U. stenocephala (geometric mean = 82.6). Against A. caninum, the efficacy of ivermectin was 52%, 98%, 95%, and 97% at 6, 12, 18, and 24 micrograms/kg, respectively. The statistical model that best described the dose response was linear to 12 micrograms/kg with a plateau thereafter. Using this model, the estimated reduction from the predicted control mean was 97.2%; the estimated dose to eliminate 90% of the worms (ED90) was 8.4 micrograms/kg, and the ED95 was 10.5 micrograms/kg. Against U. stenocephala, the dose response was linear in the range studied, with an ED90 of 20.8 micrograms/kg; it was estimated that 93.2% of the worms would be eliminated.  相似文献   
942.
Various indexes have been proposed to mark when a child is on the verge of acquiring new knowledge. This article described a new method for indexing this point of transition, which is based on the specificity of children's verbal explanations. The degree to which children were specific in their verbal explanations was related to whether they benefited from instruction. In particular, children who were vague in their explanations (i.e., less specific) benefited from instruction more than children who were explicit in their explanations (i.e., more specific). This index provides insights into the child's mental state prior to acquiring new knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
943.
BACKGROUND: Patients with treated diabetes in the randomized-trial segment of the Bypass Angioplasty Revascularization Investigation (BARI) who were randomized to initial revascularization with PTCA had significantly worse 5-year survival than patients assigned to CABG. This treatment difference was not seen among diabetic patients eligible for BARI who opted to select their mode of revascularization. We hypothesized that differences in patient characteristics, assessed and unmeasured, together with the treatment selection in the registry, at least partially account for this discrepancy. METHODS AND RESULTS: Among diabetics taking insulin or oral hypoglycemic drugs at entry, angiographic and clinical presentations were comparable between randomized and registry patients. However, more registry patients were white, and registry diabetics tended to be more educated and more physically active and to report better quality of life. Procedural characteristics and in-hospital complications were comparable. The 5-year all-cause mortality rate was 34.5% in randomized diabetic patients assigned to PTCA versus 19.4% in CABG patients (P=0.0024; relative risk [RR]=1.87); corresponding cardiac mortality rates were 23.4% and 8.2%, respectively (P=0.0002; RR=3.10). The CABG benefit was more apparent among patients requiring insulin. In the registry, all-cause mortality was 14.4% for PTCA versus 14.9% for CABG (P=0.86, RR=1.10), with corresponding cardiac mortality rates of 7.5% and 6. 0%, respectively (P=0.73; RR=1.07). These RRs in the registry increased to 1.29 and 1.41, respectively, after adjustment for all known differences between treatment groups. CONCLUSIONS: BARI registry results are not inconsistent with the finding in the randomized trial that initial CABG is associated with better long-term survival than PTCA in treated diabetic patients with multivessel coronary disease suitable for either surgical or catheter-based revascularization.  相似文献   
944.
945.
The cytoplasmic face of the Golgi contains a variety of proteins with coiled-coil domains. We identified one such protein in a yeast two-hybrid screen, using as bait the peripheral Golgi phosphatidylinositol(4,5)P2 5-phosphatase OCRL1 that is implicated in a human disease, the oculocerebrorenal syndrome. The approximately 2.8-kilobase mRNA is ubiquitously expressed and abundant in testis; it encodes a 731-amino acid protein with a predicted mass of 83 kDa. Antibodies against the sequence detect a novel approximately 84-kDa Golgi protein we termed golgin-84. Golgin-84 is an integral membrane protein with a single transmembrane domain close to its C terminus. In vitro, the protein inserts post-translationally into microsomal membranes with an N-cytoplasmic and C-lumen orientation. Cross-linking indicates that golgin-84 forms dimers, consistent with the prediction of an approximately 400-residue dimerizing coiled-coil domain in its N terminus. The dimerization potential is supported by a data base search that showed that the N-terminal 497 residues of golgin-84 contain a coiled-coil domain that when fused to the RET tyrosine kinase domain had the ability to activate it, forming the RET-II oncogene. Data base searching also indicates golgin-84 is similar in structure and sequence to giantin, a membrane protein that tethers coatamer complex I vesicles to the Golgi.  相似文献   
946.
The effects of endurance run training on Na+-dependent Ca2+ regulation in rat left ventricular myocytes were examined. Myocytes were isolated from sedentary and trained rats and loaded with fura 2. Contractile dynamics and fluorescence ratio transients were recorded during electrical pacing at 0.5 Hz, 2 mM extracellular Ca2+ concentration, and 29 degreesC. Resting and peak cytosolic Ca2+ concentration ([Ca2+]c) did not change with exercise training. However, resting and peak [Ca2+]c increased significantly in both groups during 5 min of continuous pacing, although diastolic [Ca2+]c in the trained group was less susceptible to this elevation of intracellular Ca2+. Run training also significantly reduced the rate of [Ca2+]c decay during relaxation. Myocytes were then exposed to 10 mM caffeine in the absence of external Na+ or Ca2+ to trigger sarcoplasmic reticular Ca2+ release and to suppress cellular Ca2+ efflux. This maneuver elicited an elevated steady-state [Ca2+]c. External Na+ was then added, and the rate of [Ca2+]c clearance was determined. Run training significantly reduced the rate of Na+-dependent clearance of [Ca2+]c during the caffeine-induced contractures. These data demonstrate that the removal of cytosolic Ca2+ was depressed with exercise training under these experimental conditions and may be specifically reflective of a training-induced decrease in the rate of cytosolic Ca2+ removal via Na+/Ca2+ exchange and/or in the amount of Ca2+ moved across the sarcolemma during a contraction.  相似文献   
947.
BACKGROUND: Increased expression of Ca2+-sensitive protein kinase C (PKC) isoforms may be important markers of heart failure. Our aim was to determine the relative expression of PKC-beta1, -beta2, and -alpha in failed and nonfailed myocardium. METHODS AND RESULTS: Explanted hearts of patients in whom dilated cardiomyopathy or ischemic cardiomyopathy was diagnosed were examined for PKC isoform content by Western blot, immunohistochemistry, enzymatic activity, and in situ hybridization and compared with nonfailed left ventricle. Quantitative immunoblotting revealed significant increases of >40% in PKC-beta1 (P<0.05) and -beta2 (P<0.04) membrane expression in failed hearts compared with nonfailed; PKC-alpha expression was significantly elevated by 70% in membrane fractions (P<0.03). PKC-epsilon expression was not significantly changed. In failed left ventricle, PKC-beta1 and -beta2 immunostaining was intense throughout myocytes, compared with slight, scattered staining in nonfailed myocytes. PKC-alpha immunostaining was also more evident in cardiomyocytes from failed hearts with staining primarily localized to intercalated disks. In situ hybridization revealed increased PKC-beta1 and -beta2 mRNA expression in cardiomyocytes of failed heart tissue. PKC activity was significantly increased in membrane fractions from failed hearts compared with nonfailed (1021+/-189 versus 261+/-89 pmol. mg-1. min-1, P<0.01). LY333531, a selective PKC-beta inhibitor, significantly decreased PKC activity in membrane fractions from failed hearts by 209 pmol. min-1. mg-1 (versus 42.5 pmol. min-1. mg-1 in nonfailed, P<0.04), indicating a greater contribution of PKC-beta to total PKC activity in failed hearts. CONCLUSIONS: In failed human heart, PKC-beta1 and -beta2 expression and contribution to total PKC activity are significantly increased. This may signal a role for Ca2+-sensitive PKC isoforms in cardiac mechanisms involved in heart failure.  相似文献   
948.
Professional nursing associations, unions, state regulatory boards, and even Congress are hotly debating the topic of multistate licensure. This article discusses several hurdles to implementing a multistate licensure model and explains how technology can help to overcome them.  相似文献   
949.
950.
This study examined whether the distribution of tobacco use and related psychosocial risk factors among youth in urban India vary by socioeconomic status (SES). Data were derived from a cross-sectional survey of students enrolled in the 6th and 8th grades in 32 schools in Delhi and Chennai (N = 11,642). The survey was conducted in 2004, before the implementation of a program designed to prevent and reduce tobacco use (MYTRI). Mixed-effect regression models were used (a) to determine the prevalence of tobacco use among private (higher SES) and government (lower SES) school students, (b) to investigate whether certain psychosocial factors were associated with increased tobacco use, and (c) to determine how these factors varied by school type. Ever-use of multiple forms of tobacco (e.g., gutkha, bidis, and cigarettes) was more prevalent among government school students than private school students. After adjusting for city, gender, grade, and age, we found the prevalence rate for ever-use of any tobacco product to be 18.9% for government school students, compared with 12.2% for private school students (p<.01). Students in government schools scored lower than private school students on most psychosocial risk factors for tobacco use studied here, indicating higher risk. Government school students scored the lowest for refusal skills, self-efficacy, and reasons not to use tobacco. Social susceptibility to chewing tobacco and social susceptibility to smoking were strong correlates of current tobacco use among government school students. Exposure to tobacco advertising was also a strong correlate of current tobacco use for government school students but not private school students. In two large cities of India, students attending government schools are using many forms of tobacco at higher rates than private school students. The psychosocial risk profile of government school students suggests they are more vulnerable to initiation and use and to outside influences that encourage use.  相似文献   
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