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41.
42.
Neisseria gonorrhoeae was identified by the Phadebact gonococcus test, a rapid slide coagglutination technique, and the results obtained were compared with those obtained by conventional methods (Gram stain morphology, oxidase reaction, and carbohydrate utilization tests) for the confirmatory identification of gonococci. Of 308 clinical isolates examined, the coagglutination procedure correctly identified 97.8% of the isolates tested as N. gonorrhoeae and 93.9% of other bacteria as not N. gonorrhoeae. The coagglutination procedure also identified 29 laboratory strains correctly as not N. gonorrhoeae. The slide coagglutination test is easy to perform and offers a valuable alternative to other techniques for the confirmatory identification of N. gonorrhoeae.  相似文献   
43.
The neonatal administration of testosterone propionate to Wistar rats resulted in anovulatory adults in persistent vaginal oestrus. Clomiphene citrate had a similar effect. In both groups of adults, hyperplasia of the uterine epithelium and occasional metaplasia was observed. The uterine nuclear and cytosol oestrogen and progestin receptors of these anovulatory rats were found to have affinities for their respective ligands similar to those of normal females. The nuclear oestrogen receptor comprised occupied and unoccupied components, as in normal females. The content of the nuclear oestrogen receptor was comparable with that of females in the late dioestrous or pro-oestrous phase. This content was higher in the clomiphene-treated group. Despite the relatively high nuclear oestrogen receptor content the content of progestin receptors, a putative index of the oestrogenic response, was lower in the treated rats than in normal adult females throughout the cycle. Administration of oestradiol to both treatment groups resulted in depletion of cytosol oestrogen receptor content 1 h later, which, however, was not reflected by an increase in the content of nuclear oestrogen receptors. There was no measurable increase in progesterone receptor content in treated rats after daily administration of oestrogen (5 microgram/rat) for 3 days. These changes in sex-hormone-receptor interactions involving an impairment of the normal oestrogenic response may be associated with the abnormal differentiation of the uterus in these sterile, anovulatory animals.  相似文献   
44.
A number of bacterial strains have been isolated and investigated in our search for a promising organism in the production of single-cell protein from methanol. Strain L3 among these isolates was identified as an obligate methylotroph which grew only on methanol and formaldehyde as the sole sources of carbon and energy. The organism also grew well in batch and chemostat mixed-substrate cultures containing methanol, formaldehyde, and formate. Although formate was not utilized as a sole carbon and energy source, it was readily taken up and oxidized by either formaldehyde- or methanol-grown cells. The organism incorporated carbon by means of the ribulose monophosphate pathway when growing on either methanol, formaldehyde, or various mixtures of C1 compounds. Its C1-oxidation enzymes included phenazine methosulfate-linked methanol and formaldehyde dehydrogenase and a nicotinamide adenine dinucleotide-linked formate dehydrogenase. Identical inhibition by formaldehyde of the first two dehydrogenases suggested that they are actually the same enzyme. The organism had a rapid growth rate, a high cell yield in the chemostat, a high protein content, and a favorable amino acid distribution for use as a source of single-cell protein. Of special interest was the ability of the organism to utilize formaldehyde via the ribulose monophosphate cycle.  相似文献   
45.
46.
Summary The immunohistochemical expression of MAM-3 and MAM-6 antigens was studied in developing human fetal salivary gland removed at autopsy of 22 normal fetuses of varying maturity (10–40 weeks of gestation). The onset of functional maturation in the fetal gland was seen at 21 weeks of gestational maturity. The acini and ducts then underwent distinct alterations in antigen expression with growth and maturation until the late developmental stage (33–40 weeks of gestation) when they resemble the adult salivary gland. The role of maturing duct cells in histogenesis of salivary gland tumours is discussed.  相似文献   
47.
The diaphragm of the pituitary intact rat is insensitive to the insulin-like effects of growth hormone unless weanling animals are used, and even then these effects are not achieved reliably. We report here that an intraperitoneal injection of reserpine is able to induce consistent responsiveness to ovine growth horomone (oGH) in hemidiaphragms from 20-27 day old rats as assessed by stimulation of 3H-AIB transport and 14C-phenylalanine incorporation into protein. Maximal stimulation of 3H-AIB transport (approximately 40%) can be elicited by addition of oGH (5 micrograms/ml) to hemidiaphragms after a 2 mg/kg injection of reserpine given 5 h prior to sacrifice. The degree of stimulation does not alter significantly if the rats are sacrificed 3, 5 or 12 h after administration of reserpine, although it decreases by 24 h. Administration of reserpine 3 h before sacrifice also leads to a 50% increase in 14C-phenylalanine incorporation into protein in rat diaphragms in response to the addition of oGH (5 micrograms/ml). The induced sensitivity to oGH is not due to inhibition of GH secretion by reserpine as demonstrated by RIA of plasma GH. Addition of a monoclonal antibody to the GH receptor (MAb263) did not result in a stimulation or inhibition of 3H-AIB uptake or stimulation of protein synthesis in reserpinized rat hemidiaphragms. These results suggest that reserpine can induce tissue responsiveness in rats 20-27 d.o. independent of plasma GH levels. Our results also imply that the type 1 GH receptor of Barnard, Bundesen, Rylatt and Waters (1985) does not mediate the insulin like actions of GH on rat diaphragm.  相似文献   
48.
The interaction of rat uterine cytosol oestrogen-receptor complexes with the synthetic acceptor oligo(dT)--cellulose was studied. Differences in the stability of receptor complexes and their ability to bind to oligo(dT)--cellulose on storage at 4 degrees C or when exposed to increased temperatures indicated heterogeneity of steroid- and oligonucleotide-binding sites. Dilution, dialysis and (NH4)2SO4 precipitation increased the interaction of receptor complexes with oligo(dT)--cellulose (a step termed activation). This increase may be the result of the removal of low-molecular-weight cytosol components which inhibit receptor activation, dimerization to the 5 S form, which binds to oligo(dT)--cellulose, or interaction of 5 S receptor with the oligonucleotide. Cytosol oestradiol--receptor complexes exhibited biphasic dissociation kinetics. All these manipulations resulted in an increase in the proportion of the slow-dissociating component equivalent to the increase in receptor binding to oligo(dT)--cellulose. In contrast, addition of 10mM-sodium molybdate to cytosol decreased both oligo(dT)--cellulose binding and the proportion of receptor with slow dissociation kinetics. The inclusion of proteinase inhibitors did not affect interactions of receptor with oligo(dT)--cellulose nor the dissociation kinetics. These results suggest that oligo(dT)--cellulose binding may serve to quantify the proportion of cytosol receptor in an active form capable of nuclear interaction and to help to ascertain whether a receptor system is fully functional. This binding procedure could prove useful in the evaluation of oestrogen responsivity under normal and pathological conditions.  相似文献   
49.
Breinlia booliati exhibited nocturnal subperiodicity in its natural host, Rattus sabanus in contrast to experimentally infected laboratory-reared albine rats which showed irregular fluctuations of microfilariae throughout the 24 hour cycle. All the infected albino rats showed a prepatent period between 11-14 weeks postinoculation. Three patterns of microfilaraemia were discerned during the course of infection 38/49 rats displayed a single peak, 4/49 displayed 2 peaks about 12-15 weeks apart and 7/49 showed a sustained high plateau-like pattern of microfilaraemia. Cortisone had no effect on microfilarial levels when administered to rats near postpatency and some at postpatency.  相似文献   
50.
Penicillium species have been actively studied in various fields, and many new and unrecorded species continue to be reported in Korea. Moreover, unidentified and misidentified Korean Penicillium species still exist in GenBank. Therefore, it is necessary to revise the Korean Penicillium inventory based on accurate identification. We collected Korean Penicillium nucleotide sequence records from GenBank using the newly developed software, GenMine, and re-identified Korean Penicillium based on the maximum likelihood trees. A total of 1681 Korean Penicillium GenBank nucleotide sequence records were collected from GenBank. In these records, 1208 strains with four major genes (Internal Transcribed Spacer rDNA region, β-tubulin, Calmodulin and RNA polymerase II) were selected for Penicillium re-identification. Among 1208 strains, 927 were identified, 82 were identified as other genera, the rest remained undetermined due to low phylogenetic resolution. Identified strains consisted of 206 Penicillium species, including 156 recorded species and 50 new species candidates. However, 37 species recorded in the national list of species in Korea were not found in GenBank. Further studies on the presence or absence of these species are required through literature investigation, additional sampling, and sequencing. Our study can be the basis for updating the Korean Penicillium inventory.  相似文献   
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