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41.
Intermediates of adeno-associated virus type 2 (AAV) DNA replication in an in vitro assay have been characterized. The assay involves rescue and replication of an AAV insert in pBR322. Intermediates were shown to be duplex molecules in which at least one terminus was in the extended configuration, in contrast to the hairpinned ends seen after rescue in the absence of AAV DNA replication. Also present were linear double-stranded dimers, which were characterized as either head-to-head or tail-to-tail tandems; no head-to-tail dimers were detected. The results are in accord with the current model of AAV DNA replication. 相似文献
42.
43.
44.
An electrophoretic study of genetic variation at 11 loci was performedfor a population of European minnows, Phoxinus phoxinus (L.). Ten loci, EST-1
*, EST-2
*
EST-3
*,GPD-1
*,GPD-2
*,GPI-1
*,GPI-2
*,MPI
*,6PGD
* and PGM
* were polymorphic. IDH
*wasmonomorphic. The mean number of heterozygotic loci over all 176 fish was 3.05 ± 0.104(SE). Observed mean heterozygosity was 0.28±0.058(SE) and expected mean heterozygosity was 0.27±0.054(SE). EST-2
*, EST-3
* andPGM
* were not in Hardy-Weinberg equilibrium. Length,condition, parasite numbers or male breeding characters, i.e. red colorationand tubercles, were not influenced by single enzyme loci. 相似文献
45.
46.
Lightbody James J. Peterson Ward D. Poulik M. D. 《In vitro cellular & developmental biology. Plant》1978,14(5):465-468
Summary The DAUDI lymphoblast cell line derived from a patient with Burkitt lymphoma was obtained from two different sources. One
of these (DAUDI-I) produced a factor that inhibited lymphocyte proliferation in both human and mouse regardless of the stimulator,
i.e. allogeneic lymphocytes or mitogens. Glutaraldehyde treatment eliminated production of the factor and demonstrated that
DAUDI-I was capable of stimulating normal lymphocytes in MLR. A second DAUDI cell line (DAUDI-S) did not produce the inhibitory
factor and was capable of MLR stimulation.
Supported by the Children's Leukemia Foundation of Michigan, NIH Grants AI 11013 and AI 11335, and the Kidney Foundation of
Michigan. 相似文献
47.
C M Ward 《Plastic and reconstructive surgery》1979,64(1):68-75
A system for subjective and objective clinical analysis of the lower third of the nose before and after lengthening the columella was devised, and used the study of photographs of 77 patients who had had lengthening done by one of 4 approaches. It was found that each method was equally effective in lengthening the columella and in restoring a normal relationship between the structures in the tip of triangle (the basal view of the nose). However, there were certain peculiar advantages and disadvantages of each surgical technique, and these are discussed. 相似文献
48.
Evolution of the Hong Kong influenza A sub-type. Structural relationships between the haemagglutinin from A/duck/Ukraine/1/63 (Hav 7) and the Hong Kong (H3) haemagglutinins. 总被引:3,自引:0,他引:3 下载免费PDF全文
The relationship between the haemagglutinin from the influenza virus A/duck/Ukraine/1/63 (Hav 7) and the human Hong Kong variants (H3) has been investigated. Amino-acid-sequence analysis shows that the Hav 7 haemagglutinin closely resembles the 1968 human H3 haemagglutinin in structure. However, the number of amino-acid-sequence differences (23) suggest that the Hong Kong haemagglutinin gene did not come directly from A/duck/Ukraine/1/63 but from a virus derived from it by antigenic drift during the period 1963-1968. 相似文献
49.
Richard L. Rapport II George A. Ojemann Allen R. Wyler Arthur A. Ward Jr. 《The Western journal of medicine》1977,127(3):185-189
Therapy with anticonvulsant drugs reduces the frequency and severity of seizures in many but not all epileptic patients. Unfortunately, in a significant number control remains poor even when maximal doses of multiple anticonvulsant drugs are given. Some of these patients are candidates for surgical treatment of epilepsy. The operative management of convulsive disorders is a well-established technique and is available in some centers. In selected cases, such operations are both safe and effective, with good longterm improvement or complete control in 76 percent of patients. We have summarized the 24-year experience with surgical operation for epilepsy at the University of Washington Medical Center. 相似文献
50.
The origin of protein and fatty yolk in Rana pipiens. III. Intramitochondrial and primary vesicular yolk formation in frog oocytes. 总被引:1,自引:0,他引:1
R T Ward 《Tissue & cell》1978,10(3):515-524
The precise origin of the primary yolk precursor complex or primary vesicular yolk is obscure but in its earliest recognizable stage it is a typical multivesicular body which first acquires a moderately electron-dark matrix. Following this, an extremely electron-dark amorphous material, the yolk protein, appears within the precursor. This yolk protein increases in amount as the yolk vesicle grows and by the time the precursors are about 1 micrometer in diameter this protein is partly to almost completely crystalline. Yolk originating within mitochondrial cristae unlike that in the yolk precursor complexes is crystalline from its earliest appearance. Intracristae mitochondrial yolk crystals have a spacing of 70--85 A. Their molecular organization appears in some sections as electron-dark lamellae and in others as light cylinders surrounded by an electron-dark matrix. 相似文献