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91.
Each of SPF chicken (Hi-Line strain, 2-day-old males) was inoculated with 2.5 or 5 x 10(4) oocysts by stomach tube. The oocyst was the medium type of Cryptosporidium previously isolated from Korean chicken origin, and passed in 2-day-old SPF chicken. The patterns of oocyst discharge were monitored daily, and in order to observe the ultrastructure of the developmental stages, the bursa of Fabricius of the chicken was examined by transmission electron microscopy (TEM) on the 12th day postinoculation. The prepatent period for 8 chicken was 5.9 days postinoculation on the average, and the patent period was 12.9 days. The number of oocysts discharged per day for the chicken was reached peak on day 12 postinoculation on the average. A large number of oocysts was found in fecal samples obtained from inoculated chicken on days 8-14 postinoculation. The ultrastructural feature of almost every developmental stage of the medium type from chicken was very similar to that of Cryptosporidium previously isolated from mammalia including human and birds except for the attachment site of C. muris to the mucus cell from mammalia, but dimension of the oocysts from fecal samples of the medium type was different from those of C. meleagridis and mammalia origin. The above results reveal that the medium type of Cryptosporidium of Korean chicken origin is identified as Cryptosporidium baileyi. 相似文献
92.
A case of anisakiasis causing intestinal obstruction 总被引:1,自引:0,他引:1
A 31-year old salesman living in Seoul developed suddenly abdominal pain due to intestinal obstruction. Exploratory laparotomy exhibited segmental jejunal cellulitis caused by penetrating Anisakis larva. The patient had eaten raw fish. The typical history of intestinal anisakiasis was presented with a short review of Korean patients of anisakiasis. 相似文献
93.
Cryptosporidium, a coccidian protozoa, commonly causes a self-limiting diarrheal illness in humans and animals. Fecal samples from various animals in Chonbuk district were observed using Sheather's flotation technique, Kinyoun's modified acid-fast staining, and osmic acid pre-fixed Giemsa staining. The oocysts were detected in 74 cages (29.6%) out of 250 cages of mature mice, 26 (13.3%) out of 195 mature house rats, 75(15.0%) out of 4-week-old 500 fowls, 98(19.9%) out of 6 to 8-month-old 500 pigs, and 111(22.2%) out of 2 to 5-year-old 500 dairy cattle, respectively. The degree of prevalence was slight in general, but actual prevalence was higher than infection rate because the detection rates were higher in repeated-preparation examinations in comparison to the first examination. Meanwhile, large and small types of oocysts were detected from mice, house rats, pigs, and cattle, and medium type from fowls. 相似文献
94.
Martin W. Ganal Meredith W. Bonierbale Marion S. Roeder William D. Park Steven D. Tanksley 《Molecular & general genetics : MGG》1991,225(3):501-509
Summary Genes for the major storage protein of potato, patatin, have been mapped genetically and physically in both the potato and tomato genomes. In potato, all patatin genes detected by the cDNA clone pGM01 map to a single locus at the end of the long arm of chromosome 8. By means of pulsed field gel electrophoresis (PFGE) it was possible further to delimit this locus, containing 10–15 copies of the gene, to a maximum size of 1.4 million base pairs. Hybridizations with class-specific clones suggest that the locus is at least partially divided into domains containing the two major types of patatin genes, class I and II. In tomato, patatin-homologous sequences were found to reside at the orthologous locus at the end of chromosome 8. The approximately three copies in tomato were localized by PFGE to a single fragment of 300 kilobases. Whereas the class II-specific 5 promoter sequences reside in tomato at the same locus as the coding sequences, the single class I-specific copy of the 5 promoter sequences was localized on chromosome 3 with no coding sequence attached to it. A clone from this chromosome 3 locus of tomato was isolated and by restriction fragment length polymorphism mapping it could be further shown that a similar class I-specific sequence also exists on chromosome 3 of potato. As in tomato, this copy on chromosome 3 is not linked to a coding sequence for patatin. The results are discussed with respect to genome evolution and PFGE analysis of complex gene families. 相似文献
95.
Signal peptidase I overproduction results in increased efficiencies of export and maturation of hybrid secretory proteins in Escherichia coli 总被引:4,自引:0,他引:4
Jan Maarten van Dijl Anne de Jong Hilde Smith Sierd Bron Gerard Venema 《Molecular & general genetics : MGG》1991,227(1):40-48
Summary The effects of 25-fold overproduction ofEscherichia coli signal peptidase I (SPase I) on the processing kinetics of various (hybrid) secretory proteins, comprising fusions between
signal sequence functions selected from theBacillus subtilis chromosome and the mature part of TEM-β-lactamase, were studied inE. coli. One precursor (pre[A2d]-β-lactamase) showed an enhanced processing rate, and consequently, a highly improved release of
the mature enzyme into the periplasm. A minor fraction of a second hybrid precursor (pre[Al3i]-β-lactamase), which was not
processed under standard conditions of SPase I synthesis, was shown to be processed under conditions of SPase I overproduction.
However, this did not result in efficient release of the mature β-lactamase into the periplasm. In contrast, the processing
rates of wild-type pre-β-lactamase and pre(A2)-β-lactamase, already high under standard conditions, were not detectably altered
by SPase I overproduction. These results demonstrate that the availability of SPase I can be a limiting factor in protein
export inE. coli, in particular with respect to (hybrid) precursor proteins showing low (SPase I) processing efficiencies. 相似文献
96.
A single-stage two-flap method of total ear reconstruction 总被引:2,自引:0,他引:2
A single-stage two-flap method of total ear reconstruction in congenital microtia is reported. This method was derived from the one-stage reconstruction described by Song and Song. Two flaps defined by vascular basis were elevated on the mastoid area: the superficial skin flap supplied mainly by subcutaneous pedicled arteriole perforators from the posterior auricular artery and the deeper axial-pattern fascial flap including the posterior auricular artery itself. The ear framework, exaggeratedly carved using autologous rib cartilage, could be inserted easily between the two flaps, simultaneously producing the auriculocephalic angle and the conchal wall. Intraoperative expansion of the skin flap and postoperative external ear molding also were performed to create aesthetically pleasing ears. 相似文献
97.
Kyung Hwan Jung Mahn Hoon Park Hong Mo Moon Joon Shick Rhee 《Biotechnology letters》1991,13(12):857-862
Summary In the hepatitis B surface antigen (HBsAg)-producing recombinant yeast culture medium, the supply of Bacto-yeast nitrogen base without amino acids was found to be inadequate due to the lack of the several kinds of vitamins and trace elements. When the culture medium for this recombinant yeast was supplemented with sufficient vitamins and trace elements, its growth, HBsAg production and the stability of plasmid were improved. 相似文献
98.
Although the principles and the necessity for good laboratory practice (GLP) guidelines to confirm the credibility, integrity, and quality of non-clinical laboratory studies have been known for more than a decade, culture collection activities are not subject to them. Because of recent advances in biotechnology, culture collections face increased demands not only for quality cultures but also current information. When applied in culture collections, GLP guidelines prove to be an excellent management tool as well as a cost-effective system of providing authentic and reliable microbial and cell cultures and associated data. 相似文献
99.
S W Lamberts J W Koper F H de Jong 《The Journal of steroid biochemistry and molecular biology》1992,43(5):385-388
Primary cortisol receptor resistance has been reported in 6 patients and 14 asymptomatic family members. We observed an additional 6 patients (2 males and 4 females). The male patients presented with hypertension. The female patients presented with acne, hirsutism and irregular menstruations. Dexamethasone therapy (1-1.5 mg/day) was of considerable clinical benefit. All 6 patients showed insufficient suppression of cortisol after 1 mg dexamethasone. The diurnal rhythm of ACTH and cortisol was intact, albeit at an elevated level. There was a normal increase of ACTH, cortisol, and GH to insulin-induced hypoglycemia, while cortisol production was (slightly) elevated. Adrenal androgen levels were increased in all patients. Glucocorticoid receptors measured in a whole cell dexamethasone binding assay in mononuclear leukocytes showed a lowered affinity in 1, and lowered numbers of receptors in 4 patients. In 1 patient no abnormalities were found. As a "bioassay" for glucocorticoid action dexamethasone suppressibility of mitogen-stimulated incorporation of [3H]thymidine in mononuclear leukocytes was measured. In this last patient dexamethasone suppressibility of [3H]thymidine incorporation was significantly lowered. Twelve months' treatment with 200 mg RU 486 per day in meningioma patients induced a similar biochemical picture as observed in primary cortisol receptor resistance. Partial cortisol receptor resistance might be less rare than previously thought. In the 6 patients presented at least 3 different forms can be recognized. Therapy with dexamethasone was successful in female patients with acne and hirsutism, as the secondary overproduction of adrenal androgens was effectively controlled. Chronic therapy with RU 486 causes a biochemical picture similar to primary cortisol receptor resistance. 相似文献
100.
D. -L. Wei S. -C. Chang Y. -H. Wei Y. -W. Lin C. -L. Chuang S. -C. Jong 《World journal of microbiology & biotechnology》1992,8(2):141-146
Eighteen strains of xylariaceous fungi have been screened for higher activities of cellulolytic enzymes,Trichoderma reesei QM 9414 was also examined for comparison. Strains ofXylaria anisopleura andX. regalis had higher endocellulase (CMCase) and exocellulase (Avicelase) activities after 2 weeks' incubation.Hypoxylon stygium produced the highest activity of -glucosidase 3 days after inoculation. The optimum pH for these cellulolytic enzymes was approx. 5.0 and the optimum temperatures ranged from 37 to 50°C. A mixed culture process usingT. reesei QM 9414 andH. stygium was developed to obtain enhanced synthesis of cellulase. -Glucosidase activities in the mixed culture increased within 48h whenH. stygium was introduced after 24h. 相似文献