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41.
MP Lisovoi NM Lesovoy GI Vasechko 《Archives Of Phytopathology And Plant Protection》2013,46(2):123-127
A new method of selection of the winter wheat varieties has been tested for resistance to the pest insects' complex by the traits of plants that are the markers of plant resistance. It makes it possible to use this method from year to year independently of the pests' density. 相似文献
42.
TD Smith KP Bhatnagar CJ Bonar KL Shimp MP Mooney MI Siegel 《American journal of physical anthropology》2003,122(3):301-301
43.
The aim of this experiment was to evaluate the effects of an intracerebroventricular (icv) injection of prostaglandin E1 (PGE1) on the sympathetic activation and the thermogenic changes in rats with acute lesions of the ventromedial hypothalamus (VMH). Four groups of six Sprague-Dawley male rats were anesthetized with ethyl-urethane. The firing rate of the sympathetic nerves innervating the interscapular brown adipose tissue (IBAT) and the colonic and IBAT temperatures were monitored both before and after one of the following treatments: 1) VMH lesion plus icv injection of PGE1 (500 ng); 2) VMH lesion plus icv injection of saline; 3) sham lesion plus icv injection of PGE1; and 4) sham lesion plus icv injection of saline. PGE1 induced an increase in the firing rate of IBAT nerves and the colonic and IBAT temperatures. These effects were reduced by VMH lesion. The findings indicate that acute lesions of the VMH reduce the effects of PGE1 and seem to suggest a possible role played by the VMH in the control of the sympathetic activation and the thermogenic changes during PGE1 hyperthermia. 相似文献
44.
Joanne T. Emerman Eveline E. Fiedler Anthony W. Tolcher Patricia M. Rebbeck 《In vitro cellular & developmental biology. Plant》1987,23(2):134-140
Summary We compared the effects of defined medium, fetal bovine serum (FBS) and human serum (HuS) on the growth and responses to chemotherapeutic
agents of human breast cancer cells in primary culture. Normal and tumor tissues were dissociated to small aggregates and
single cells and seeded onto collagen-gel-coated wells in defined medium or medium supplemented with 5% FBS or 5% HuS. In
all cases examined, defined medium and medium containing HuS were superior to medium containing FBS in supporting growth of
both normal and tumor cell cultures. However, cultures in defined medium showed an initial cell loss. Cells from the same
tumor cultured in different media varied in their responses to chemotherapeutic agents. In light of these results, medium
supplemented with HuS, which promoted attachment of these cells in culture and stimulated their growth, should be the most
appropriate nutrient environment for determining the effects of therapeutic agents on cells as it most closely resembles the
in vivo situation. Because there were also variations in growth rates and chemosensitivities of tumor cells cultured in different
human serum samples, we suggest that optimal conditions in which to culture these cells include the serum of the patient whose
tumor is removed. This serum may provide host factors that influence cell growth and interact with exogenous factors.
This work was supported by a grant from the National Cancer Institute of Canada and funds contributed by Mr. B. T. Wharton
in memory of his wife, Nadia. J. T. Emerman is a research scholar of the National Cancer Institute of Canada. 相似文献
45.
Multiple haplotypes from each of three nuclear loci were isolated and
sequenced from geographic populations of the American oyster, Crassostrea
virginica. In tests of alternative phylogeographic hypotheses for this
species, nuclear gene genealogies constructed for these haplotypes were
compared to one another, to a mitochondrial gene tree, and to patterns of
allele frequency variation in nuclear restriction site polymorphisms
(RFLPs) and allozymes. Oyster populations from the Atlantic versus the Gulf
of Mexico are not reciprocally monophyletic in any of the nuclear gene
trees, despite considerable genetic variation and despite large allele
frequency differences previously reported in several other genetic assays.
If these populations were separated vicariantly in the past, either
insufficient time has elapsed for neutral lineage sorting to have achieved
monophyly at most nuclear loci, or balancing selection may have inhibited
lineage extinction, or secondary gene flow may have moved haplotypes
between regions. These and other possibilities are examined in light of
available genetic evidence, and it is concluded that no simple explanation
can account for the great variety of population genetic patterns across
loci displayed by American oysters. Regardless of the source of this
heterogeneity, this study provides an empirical demonstration that
different sequences of DNA within the same organismal pedigree can have
quite different phylogeographic histories.
相似文献
46.
47.
Crustacean and cheliceratan hemocyanins (oxygen-transport proteins) and
insect hexamerins (storage proteins) are homologous gene products, although
the latter do not bind oxygen and do not possess the copper- binding
histidines present in the hemocyanins. An alignment of 19 amino acid
sequences of hemocyanin subunits and insect hexamerins was made, based on
the conservation of elements of secondary structure observed in X-ray
structures of two hemocyanin subunits. The alignment was analyzed using
parsimony and neighbor-joining methods. Results provide strong indications
for grouping together the sequences of the 2 crustacean hemocyanin
subunits, the 5 cheliceratan hemocyanin subunits, and the 12 insect
hexamerins. Within the insect clade, four methionine- rich proteins, four
arylphorins, and two juvenile hormone-suppressible proteins from
Lepidoptera, as well as two dipteran proteins, form four separate groups.
In the absence of an outgroup sequence, it is not possible to present
information about the ancestral state from which these proteins are
derived. Although this family of proteins clearly consists of homologous
gene products, there remain striking differences in gene organization and
site of biosynthesis of the proteins within the cell. Because studies on
18S and 12S rRNA sequences indicate a rather close relationship between
insects and crustaceans, we propose that hemocyanin is the ancestral
arthropod protein and that insect hexamerins lost their copper-binding
capability after divergence of the insects from the crustaceans.
相似文献
48.
This paper looked at the leaf architecture characteristics of Vachellia tortilis to determine if either there is or not an effect of the tropic line on plants. Vachellia tortilis leaves were sampled along a national road (N1) in Limpopo province. Sampling points were set 10 km apart away from the Tropic of Capricon in opposite directions. Leaf morphology revealed that leaves of V. tortilis are bipinnately compound with alternate arrangement. The venation pattern of the pinnules was eucamptodromus and brochidodromous with imperfect reticulation. Areoles were imperfect and pentagonal or irregular in shape. 相似文献
49.
Julieta Ramos-Elorduy José MP Moreno Adolfo I Vázquez Ivonne Landero Héctor Oliva-Rivera Víctor HM Camacho 《Journal of ethnobiology and ethnomedicine》2011,7(1):1-22
In this paper, we reported the butterflies and moths that are consumed in Mexico. We identified 67 species of Lepidoptera that are eaten principally in their larval stage in 17 states of Mexico. These species belong to 16 families: Arctiidae, Bombycidae, Castniidae, Cossidae, Geometridae, Hepialidae, Hesperiidae, Lasiocampidae, Noctuidae, Nymphalidae, Papilionidae, Pieridae, Pyralidae, Saturniidae, Sesiidae, and Sphingidae. Saturniidae, Pieridae, Noctuidae and Nymphalidae were the more species consumed with 16, 11, 9, and 8 species, respectively. The genera with the largest numbers of species were: Phassus, Phoebis, Hylesia and Spodoptera, with three species. Their local distribution, corresponding to each state of Mexico, is also presented. 相似文献
50.
Jasmin Ana Luiza M Torres Henrique MP Nunes Juliana A Passipieri Linda A Jelicks Emerson L Gasparetto David C Spray Antonio C Campos de Carvalho Rosalia Mendez-Otero 《Journal of nanobiotechnology》2011,9(1):4