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121.
Jeanette J. Chen Erla R. Smith Gary D. Gray Julian M. Davidson 《Primates; journal of primatology》1981,22(2):253-260
Seasonal changes in body weight, plasma testosterone and ejaculatory capacity were observed in five intact and two testosterone-implanted
castrated squirrel monkeys for a total of 13 months. Electroejaculation was employed for obtaining data concerning ejaculation.
In the intact animals, there were significant increases in body weight, ejaculate volume and plasma testosterone during the
breeding season. With the exception of one animal, there was also a decrease in ejaculation latency during the season. Seasonal
differences in the sperm count and sperm motility were not observed. Testosterone-implanted castrates showed changes in both
ejaculate volume and ejaculation latency similar to those seen in intact monkeys during the breeding season. The body weight
and plasma testosterone of the castrates remained quite constant throughout the year.
Supported by NIH grants HD 00778, MH 21178 and MH 23645. 相似文献
122.
Arlette Acoutte-Panvier Julian E. Davies Linda R. Gritz Barbara S. Littlewood 《Molecular & general genetics : MGG》1980,179(2):273-282
Summary The cytoplasmic ribosomal proteins (r-proteins) of seventeen yeast species of the genera Saccharomyces and Kluyveromyces were analyzed by one-dimensional gradient polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. The electrophoretic patterns of cytoplasmic r-proteins from different species display extensive differences in both the 40S and the 60S subunit. Relatedness of species suggested by r-protein patterns correlates well with that based on DNA/DNA homology (Bicknell and Douglas 1970). Immunochemical cross-reactions and antibiotic susceptibility tests were also used to compare different species.Analyses of r-proteins from two different interspecific hybrids showed that their ribosomes were hybrid, containing r-proteins from both parents. These findings are discussed in relation to the evolution of yeast species and the regulation of expression of r-proteins in cucaryotes. 相似文献
123.
Eugenia mcvaughii is described from a forest remnant of the Jardin Botánico of Caracas, Venezuela. Found also in the hills adjacent to Caracas, it may be considered as an endemic species of the Interior Coastal Cordillera. 相似文献
124.
On some commensal Turbellaria of the Canadian East Coast 总被引:2,自引:1,他引:1
The brachyurans Chionoecetes opilio and Hyas araneus collected from the east coast of Canada harbour two species of commensal turbellarians. Ectocotyla hirudo (Levinsen) and E. multitesticulata Fleming & Burt are found on the gills and branchial chambers of male and female crabs. The molluscs Crassostrea virginica and Mytilus edulis collected from several locations where they are cultured along the Northumberland strait carry two commensal eulecithophoran turbellarians, both on the gills, viz., Urasloma cyprinae (Graff) and Paravortex gemellipara (Linton), the latter being a new host record. Aspects of the biology and life-history of these turbellarians are discussed, especially in relationship to the biology of their hosts.Abbreviations in the figures A
Atrium
- An
Antrum
- C
Capsule
- CO
Common Oviduct
- E
Embryo
- Ep
Egg-laying pore
- GP
Genital Pore
- I
Intestine
- O
Ovary
- Od
Oviduct
- Og
Ora-genital Pore
- Ph
Pharynx
- Sp
Sperm
- SV
Seminal Vesicle
- T
Testes
- Va
Vagina
- Y
Yolk 相似文献
125.
Julian A. Steyermark 《Brittonia》1980,32(1):17-23
Three new species,Lubaria szczerbanii (Rutaceae),Croton guaiquinimae (Euphorbiaceae), andStomatochaeta colveei (Asteraceae), are described from the summit of Cerro Guaiquinima, Venezuela. The generic affinities betweenLubaria andMyllanthus, and betweenStomatochaeta andStenopadus are discussed. 相似文献
126.
127.
Julian A. Steyermark 《Brittonia》1978,30(1):39-49
Ten new species (Billbergia manarae, Croizatia naiguatensis, Croton huberi, Rinorea oraria, Anaectocalyx manarae, Linociera avilensis, Cynanchum beatricis, C. manarae, Matelea costanensis, and M. manarae) are described in preparation for the forthcoming Flora of Avila and Naiguatá. 相似文献
128.
The distribution pattern of silver-NORs was studied in cells of six-day blastocysts and kidney fibroblasts of the rabbit using
the Ag-AS technique. At metaphase and interphase there was a binomial distribution of the number of stained sites in both
populations but blastocysts had a greater percentage of cells with larger numbers of stained sites. Up to 7 of the 8 chromosomes
known to bear NORs were stained in cells from blastocysts while a maximum of 6 were stained in fibroblasts. A significant
difference was found between the mean numbers of chromosomal NORs per cell in metaphases from blastocysts and fibroblasts,
where they were 4.2 and 3.3 respectively. Similarly, the mean number of NORs in interphase was significantly greater in cells
from blastocysts. The distribution of staining on chromosome pair 13 was related to cell type. Significantly more cells in
blastocysts than fibroblasts showed staining in this chromosome pair. 相似文献
129.
T. E. Devine C. D. Foy A. L. Fleming C. H. Hanson T. A. Campbell J. E. McMurtrey III J. W. Schwartz 《Plant and Soil》1976,44(1):73-79
Summary Aluminum toxicity limits root growth in acid subsoils that are difficult to lime. An alternative to subsoil liming is the development of plants having greater tolerance to Al. Alfalfa (Medicago sativa L.) is considered an Al-susceptible species. Preliminary studies indicated that alfalfa cultivars differ in Al tolerance, but the extreme plant-to-plant variation within cultivars prevented the establishment of clearcut cultivar differences.Tolerant and susceptible plants were selected from each of six cultivars (DuPuits, Atlantic, Team, Buffalo, Grimm, and Sirsa 9) grown on an Al-toxic Bladen soil at pH 4.1 to 4.3. The tolerant selections were repotted and interpollinated to form one population of polycross seed. Susceptible selections were treated similarly to form a second population. These two populations, tolerant and susceptible, were subjected to an additional cycle of recurrent phenotypic selection for tolerance and susceptibility, respectively, to Al-toxic Bladen soil at pH 4.6.Plants from the population selected for tolerance to the acid Bladen soil were significantly higher in both root and top vigor on Al-toxic Tatum soil than plants from the population selected for susceptibility. The results indicated that Al tolerance is a heritable trait in these alfalfa populations and that recurrent selection can be used effectively to develop strains having differential tolerance to Al-toxic soils. The observation that only 2% of the plants from the tolerant population were in the most tolerant class suggests a good opportunity for more progress in selecting toward Al tolerance. 相似文献
130.
The enzyme tyrosinase (E.G. 1.14.18.1) has been immobilized in a polyacrylamide gel and intermittently assayed for enzyme activity over a period of 19 days using phenol as the substrate. The results of these studies indicate that the immobilized enzyme could be incorporated into a system to detect phenol and related compounds that are found in industrial effluents and as surface water contaminants. 相似文献