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41.
A new method for the extraction of bile acids from aqueous solutions, urine, plasma, and bile is described. A buffered solution of decyltrimethylammonium bromide is added to the sample to give a 0.03 m concentration of the counter-ion. The mixture is passed through a bed of Lipidex 1000, which is then washed with the buffered solution of counter-ion followed by water. The decyltrimethylammonium salts of bile acids are sorbed by the Lipidex and are eluted with methanol. Recoveries of unconjugated, taurine- and glycine-conjugated, sulfated, and glucuronidated bile acids are close to 100%. Unconjugated bile acids can also be quantitatively extracted from aqueous solutions and urine after acidification with acetic acid. 相似文献
42.
An-Fei Hsu Dorothy Brower Ronald B. Etskovitz Peter K. Chen Donald D. Bills 《Phytochemistry》1983,22(7):1665-1669
A radioimmunoassay (RIA) procedure for the determination of pmol quantitites of morphine in capsule samples of Papaver somniferum was developed. An antiserum developed against a conjugate of morphine-3-hemisuccinate-BSA was relatively specific for morphine and possessed moderated cross-reactivity with codeine and mild cross-reactivity with thebaine, but none with narceine, papaverine, or noscapine. The standard curve was linear over a range of 0.01–0.20 ng. This assay allows for the rapid, sensitive and precise determination of morphine in unpurified aqueous extracts of capsule samples. The amounts of morphine in the aqueous extracts determined by radioimmunoassay were validated by high performance liquid chromatography (HPLC). The two methods show a high correlation coefficient (r = 0.98) with no significant difference in determinations of morphine content by RIA and HPLC. 相似文献
43.
Esmail Behboodi David F. Katz James W. Overstreet Andrew G. Hendrickx 《Molecular reproduction and development》1989,24(3):333-342
Postcoital (pc) cervical mucus was collected in 73 menstrual cycles of cynomolgus monkeys and in 43 cycles of rhesus monkeys at 2,6,10,30 hr pc. Videomicrography was used to analyze sperm numbers and movement in the mucus. Both cynomolgus and rhesus monkeys had comparable populations of motile sperm in the mucus at 2 hr pc. However, by 6 hr pc, cervical mucus from cynomolgus monkeys contained twice as many total sperm and motile sperm as mucus from rhesus monkeys (P <.05). Mean swimming speeds of the free-swimming cervical sperm were similar for the two species at this time. No motile sperm were recovered in mucus from rhesus monkeys at 30 hr pc. In cynomolgus monkeys, however, 14 of the 26 animals examined at 30 hr pc had motile sperm in their mucus. These sperm exhibited lower percent molility, percent free-swimming sperm, and swimming speed than those sperm observed at 6 hr pc. Uterine sperm were collected by transcervical or transuterine aspiration from cynomolgus monkeys. In the transcervical technique, sperm were successfully obtained in four of nine animals examined at 6 hr and in four of five animals at 30 hr pc. The percentage of motile sperm in the uterine fluid was high, 82% ± 4%, and the swimming speeds (86 ± 2μm/sec) were higher than those observed in cervical mucus. Approximately 5–10% of the uterine sperm exhibited swimming motions similar to the hyperactivated motility seen in most mammals. These findings indicate that the sperm cervical mucus interaction in vivo in cynomolgus monkeys has more similarities to the human situation than does the interaction in rhesus monkeys. 相似文献
44.
Joleen L. Zackowski Patricia A. Martin-DeLeon 《Molecular reproduction and development》1989,22(1):93-107
The meiotic segregants of male mice heterozygous for Rb(6.16)24Lub and Rb(16.17)7Bnr were viewed, for the first time, at first cleavage metaphase. Chromosomes were analyzed after G-banding, C-banding, and karyotyping. To study sperm aging effects, chromosomes of 202 one-cell zygotes derived from males mating at intervals of approximately 3,14, and 21 days were examined. At least 89.6% of sperm-derived complements were products of 2:2 segregation; at most, a possible 6.4% were 3:1 segregants. The six expected types of 2:2 segregants, both balanced and unbalanced, were equifrequent in the total zygote population derived from sperm of all ages. When the data were analyzed according to mating frequency, the 3-day sperm population considered most likely to be fresh showed a deficiency of the segregant nullisomic for chromosome 6 and disomic for chromosome 17, when compared with the reciprocal segregant (P < 0.025) as well as to all other 2:2 segregants (P < 0.05). However, these sperm fertilized in greater numbers (P < 0.01) than their reciprocal segregant (disomic for 6 and nullisomic for 17) in the 14-day sperm population. While sperm with chromosomal abnormalities are capable of fertilization, the competence of segregants nullisomic for 6 and disomic for 17 apparently depends on the prior storage period in the male. Further, the results suggest that the effect of aneuploidy on sperm function is dependent on the specific chromosome(s) involved. 相似文献
45.
Our objective was to examine the ability of nucleate and anucleate fragments of artificially activated mouse eggs to transform sperm nucleus into male pronucleus. To this end, zona-free oocytes in metaphase II were activated by ethanol and bisected into halves (one with the spindle, the other anucleate) either within 10 to 20 min (series A) or 3 or 5 hr later (series B). In series A, the fragments were inseminated 3,5, and 8 h after activation, and in series B. 3 and 5 h after activation. Both nucleate and anucleate fragments lose the capability of transforming sperm nucleus into fully formed pronucleus sometime between 3 and 5 h after activation. In 8 h old parthenogenetic fragments, the majority of sperm nuclei remain unchanged or begin decondensation but never reach the stage of an early pronucleus. In over 1/3 of anucleate fragments of this age group, sperm nuclei develop defectively: chromatin decondenses inside the persisting nuclear envelope. In other experimental groups, the incidence of these abnormal sperm nuclei varies between 0 and 10%. In general, the anuclcate fragments retain the capability to transform sperm nuclei (fully or partially) longer than their nuclear counterparts. This difference may be accounted for by a different level of substances required for pronuclcar growth (extrachromosomal constituents of the germinal vesicle and nuclear lamins): high and constant in the cytoplasm of anucleate egg halves and low and progressively decreasing in the nucleate halves because of their putative uptake by the female pronucleus. However, the cytoplasmic factors responsible for the initial stages of transformation (nuclear envelope breakdown, chromatin decondensation) become eventually inactivated both in the presence and in the absence of a female pronucleus. 相似文献
46.
Scott K. Sakaluk Anne-Katrin Eggert 《Evolution; international journal of organic evolution》1996,50(2):694-703
Manipulation of ejaculates is believed to be an important avenue of female choice throughout the animal kingdom, but evidence of its importance to sexual selection remains scarce. In crickets, such manipulation is manifest in the premature removal of the externally attached spermatophore, which may afford females an important means of postcopulatory mate choice. We tested the hypothesis that premature spermatophore removal contributes significantly to intraspecific variation in sperm precedence by (1) experimentally manipulating spermatophore attachment durations of competing male Gryllodes sigillatus and (2) employing protein electrophoresis to determine the paternity of doubly mated females. The relative spermatophore attachment durations of competing males had a significant influence on male paternity, but the pattern of sperm precedence deviated significantly from the predictions of an ideal lottery. Instead, paternity data and morphological evidence accorded best with a model of partial sperm displacement derived here. Our model is similar to a displacement model of Parker et al. in that sperm of the second male mixes instantaneously with that of the first throughout the displacement process, but the novel feature of our model is that the number of sperm displaced is only a fraction of the number of sperm transferred by the second male. Regardless of the underlying mechanism, female G. sigillatus can clearly alter the paternity of their offspring through their spermatophore-removal behavior, and employ such cryptic choice in favoring larger males and those providing larger courtship food gifts. We discuss how female control of sperm transfer and intraspecific variation in sperm precedence may be important precursors to the evolution of gift giving in insects. 相似文献
47.
Frederick J. Griffin Carol A. Vines Murali C. Pillai Ryuzo Yanagimachi Gary N. Cherr 《Development, growth & differentiation》1996,38(2):193-202
Polyclonal antibodies were generated to the 105 kDa herring sperm motility initiation factor (SMIF) and used to explore the role of SMIF in sperm-egg interaction. Using sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting with SMIF antibodies, it was demonstrated that SMIF is present as a minor (4–7% of total chorion protein) component of the chorion. The major polypeptides in the chorion migrated at 117 kDa and in a grouping between 48–54 kDa, with other minor bands above and below. The only detectable glycosylated component was the 105 kDa band, which was resolved at two isoelectric points (8.22 and 8.31) after isoelectric focusing gel electrophoresis. Using antibodies to SMIF, fertilization was blocked, sperm motility was inhibited in vitro in the presence of solubilized SMIF and SMIF binding sites on sperm were localized. Lastly, SMIF was localized to the region of the herring egg that encircles the micropyle. 相似文献
48.
ANDREAS TADLER 《Zoological Journal of the Linnean Society》1996,118(1):83-97
The functional anatomy of the genitalia of Nemasoma varicorne (Nemasomatidae), Brachyiulus lusitanus, Unciger foehdus and Cylindroiulus boleti (Julidae) was investigated by shock freezing of animals in copula followed by serial semithin sectioning of the engaged genitalia. The species show conspicuous differences in the functional mechanism of their genitalia. In M varicorne and B. lusitanus the vulvae remain within the vulval sac during copulation while in U.foetidus and C. boleti parts of the gonopods (promerite and mesomerite) form clasper-like structures that pull out the vulvae from the vulval sacs. With the exception of C. boleti all investigated species have a 'central funnel' on the vulva which leads into the receptaculum seminis. The sperm-transferring part of the male gonopods (solenomerite) is introduced into this funnel during copulation. In B. lusitanus and C. boleti a projection of the posterior gonopods (end-projection, brachite) fits into a slit anterior to the openings of the receptacula. The results are discussed with regard to sexual selection theory and a hypothesis is proposed that explains the evolutionary change of millipede genitalia by a combination of female choice and sperm competition phenomena. 相似文献
49.
Abstract: Possible effects on the physiological activity and culturability of soil microorganisms by different soil dispersion procedures, and effects on activity caused by extracting bacteria from soil, were investigated. There was no apparent difference in cfu's with dispersion of a silty loam soil and a loamy sand soil with pyrophosphate as compared to dispersion in NaCl. Substrate-induced respiration was reduced in the silty loam soil, and methanol oxidation was reduced in the loamy sand soil with dispersion in pyrophosphate, and the soil pH was irreversibly increased by the treatment. Extracted bacterial fractions had lower numbers of culturable cells as percentage of the total number of bacteria in each fraction, lower respiration rates and no methanol oxidation activity as compared to the soil slurry both before and after extraction. The physiological activity was apparently not affected by the number of cells extracted. This indicates that the increased extraction rate of indigenous soil bacteria obtained by effective disruption of aggregates and detachment of cells from surfaces, only results in increased extraction of cells that have been physiologically changed as a result of the extraction process. 相似文献
50.
Yuzuru Hamada Toshifumi Udono Migaku Teramoto Tsutomu Sugawara 《Primates; journal of primatology》1996,37(3):279-295
Growth of chimpanzees reared at the Kumamoto Primates Park of Sanwa Kagaku Kenkyusho Co. Ltd. was studied cross-sectionally
from the viewpoints of somatic growth and reproductive maturation. Distance and velocity curves were expressed using spline
function method. Males showed adolescent growth acceleration in body weight, with a peak at 7.86 yrs of age, but not in trunk
length. Females showed continuous rapid growth from mid-juvenile to adolescent phase in both body weight and trunk length,
but no isolated adolescent spurt. The Sanwa chimpanzees matured at about 12.5 yrs of age for females and 15.0 yrs for males.
The mean adult weights and trunk lengths were 53.2 kg and 507.8 mm for males and 42.7 kg and 481.6 mm for females. The Sanwa
chimpanzees had similar growth patterns to those of the Yerkes chimpanzees, although they showed a slight delay in infancy,
and a higher growth rate from the early juvenile phase onwards. Growth patterns in these two laboratories may be regarded
as “normative” for laboratory-reared chimpanzees. They matured earlier than wild chimpanzees by more than two years. The major
reason for the retarded maturation in wild chimpanzees is the delay of growth from infant to the early juvenile phases (0–4
yrs of age), probably owing to a limited nutritional supply from the mother. Development of the testes comprised three phases:
slow growth from infant to juvenile (until 6.4 yrs); rapid growth around adolescence (until 9.2 yrs); and adult (mean testicular
volume, 187 cm3). Setting the nutritional standard at 2,000–2,600 Cal/day (= Kcal/day) per adult, calories were considered for captive chimpanzees
in each age class. 相似文献