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31.
The cry genes of Bacillus thuringiensis encode a diverse group of crystal-forming proteins that exhibit insecticidal activity, particularly against the larvae of lepidopteran, coleopteran, and dipteran insects. The efficacy of B. thuringiensis-based biopesticides may be improved through the genetic manipulation of these genes. A gene transfer system has been developed for the introduction and maintenance of cloned insecticidal cry genes on small plasmids in B. thuringiensis. This vector system combines a B. thuringiensis plasmid replicon and an indigenous site-specific recombination system that allows for the selective removal of ancillary or foreign DNA from the recombinant bacterium after introduction of the Cry-encoding plasmid. The site-specific recombination system is useful for engineering strains with unique combinations of cry genes, resulting in new active ingredients with improved insecticidal properties. 相似文献
32.
BACKGROUND AND OBJECTIVE: To evaluate the response of intraocular pressure (IOP) to retrobulbar and peribulbar anesthesia. PATIENTS AND METHODS: Patients were prospectively masked and randomized to receive either 4 cc of retrobulbar anesthesia (X = 29) or 6 cc of peribulbar anesthesia (X = 30), each consisting of a 50:50 mixture of 2% xylocaine and 0.75% bupivacaine with 150 units of hyaluronidase. IOPs were measured pre-anesthesia and 1, 2, and 5 minutes post-anesthesia in nonglaucoma patients undergoing cataract extraction and intraocular lens implantation. RESULTS: Mean IOPs in the retrobulbar group as determined with a tonometer were 18.24, 18.66, 19.14, and 17.86 mm Hg pre-anesthesia and 1, 2, and 5 minutes post-anesthesia, respectively. In the peribulbar group, the mean IOPs were 18.53, 21.20, 20.40, and 19.20 mm Hg, respectively. The 1-minute pressures in the two groups were statistically different (P = .023). Within the peribulbar group, the 1- and 2-minute pressures were statistically different from the pre-anesthesia IOP (P = .001 and P = .018, respectively). CONCLUSION: Peribulbar anesthesia, with its higher volume of anesthetic (6 vs 4 cc), results in a higher initial IOP. This difference was slight and short lived, and occurred in the absence of any external ocular compression. This study may have application in avoiding elevation of IOP in select patients undergoing a local procedure. 相似文献
33.
In this paper an analytical solution for the quasistationary eddy current distribution in a hollow sphere is presented using a divergence free vector potential derived from another spatial vector function by applying the curl operator. The field is excited by a dipole of arbitrary orientation and position. The dissipated power is also considered and hints are given for the analytical treatment of multishield problems excited by current loops 相似文献
34.
35.
IK Temple RJ Gardner DO Robinson MS Kibirige AW Ferguson JD Baum JC Barber RS James JP Shield 《Canadian Metallurgical Quarterly》1996,5(8):1117-1121
Transient neonatal diabetes mellitus (TNDM) is a rare form of childhood diabetes which usually resolves in the first 6 months of life but which predisposes to type 2 diabetes of adult onset. We recently reported paternal uniparental isodisomy of chromosome 6 (UPD6) in two children with TNDM and proposed that there may be an imprinted gene important in the aetiology of diabetes on chromosome 6. We now describe two unrelated families which independently suggest that the gene is imprinted, is paternally expressed and maps to 6q22-q23. One family has a duplication while the other, with familial TNDM, shows linkage to a marker in this region. 相似文献
36.
37.
Chen Y.G. Crumley R. Lloyd S. Baum C.E. Giri D.V. 《Electromagnetic Compatibility, IEEE Transactions on》1988,30(4):449-456
A buried transmission line formed by vertical conductors can function as a wave guiding structure in producing a part of the electromagnetic field distribution caused by a distributed source at the air-earth interface. Such a structure, when excited by an appropriate low-frequency source, is a viable EMP simulation technique for use with underground systems. In the developmental phase of such a technology, there exists a need to artificially elongate the buried line by using lumped element networks. In effect, such networks simulate the simulator plates and earth. The authors address such a network concept and its design considerations. The actual design, fabrication, and testing of an example network are also presented 相似文献
38.
We report the findings of a cross-sectional epidemiologic study of Giardia lamblia and Cryptosporidum infections in Jamaica. Three hundred twenty eight stool samples from patients less than one to 81 years of age were examined using formalin-ether concentration for G. lamblia, Zeihl-Neelsen staining for Cryptosporidium, and the Prospect rapid enzyme immunoassay (EIA; Alexon, Sunnyvale, CA) for parasite diagnosis. The Prospect Giardia rapid assay detected 17 cases of G. lamblia infection compared with six by formalin-ether concentration. However, the Prospect Cryptosporidum EIA did not increase the rate of detection of Cryptosporidum when compared with Zeihl-Neelsen staining. Cryptosporidum infections were most frequently diagnosed in children less than five years old and prevalence decreased with age. In contrast, the prevalence of giardiasis increased as children became older. There were no associations between the infections and stool consistency, clinical manifestations, or sex of the individuals. The contribution of the parasites to childhood morbidity will depend on accurate laboratory diagnosis. 相似文献
39.
Tymchuk Alexander J.; Drapkin Robin; Major-Kingsley Susan; Ackerman Andrea B.; Coffman Elizabeth W.; Baum Maureen S. 《Canadian Metallurgical Quarterly》1982,13(3):412
Discusses the inadequacy of old, and the lack of new guidelines for the protection of the rights of individuals in psychological treatment. A questionnaire containing vignettes of clinical and research situations that required decision-making processes was completed by 113 members of the Division of Clinical Psychology of the American Psychological Association. Data suggest that there is inconsistency in decision making. Suggestions for improving the decision-making process and enhancing consistency are presented. (8 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
L Weing?rtner I Richter R Patsch HH Thiemann W Br?mme W Baum U Vorwald 《Canadian Metallurgical Quarterly》1977,147(2):186-198
Various dates on amoxicillin (resorption, distribution, elimination, tissue passage, urinary excretion) are presented. The bacterial spectrum is more fully discussed. Amoxicillin is compared with ampicillin. Dosage and therapeutical results are presented. Within repeated bronchoscopic examinations necessary on account of bronchopulmonary affections determination of germs were done in 88 children. At the same time examination of ampicillin levels in bronchial secretions were performed after amoxicillin therapy with different high doses (3 x 125 mg to 3 x 750 mg) for 7 days. It could be shown that good antibiotic levels could be found in secretion specimens above all obtained 2 to 4 hours after the last amoxicillin administration. They could be found too, if there did not exist any purulent secretion or stronger inflammation. There are relations between the amount of dosage, the level in secretion as well as the influence on germs. 相似文献