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991.
George K. Morris Arnold Steigerwalt James C. Feeley Edward S. Wong William T. Martin Charlotte M. Patton Don J. Brenner 《Journal of clinical microbiology》1980,12(5):718-721
A new species of Legionella was isolated from soil collected from a creek bank. The name Legionella gormanii sp. nov. is proposed. 相似文献
992.
Mice were injected intraperitoneally (i.p.) with 300 mg of cyclophosphamide (CY)/kg of body weight, and 24 h later were injected i.p. with varying dosages of yeast-phase cells of Histoplasma capsulatum. At specific time intervals organs were removed, ground, and cultured to determine the number of viable organisms contained in the spleen, liver, and lungs. Injection of mice with CY was found to cause a dramatic increase in the numbers of parasites isolated from these organs when compared with non-drug-treated controls. Mice given 10(7) yeast cells showed the largest increase in colony numbers. A greater than fivefold increase in the numbers of organisms isolated from the spleens of CY and 10(3) yeast cell-treated mice, as compared with non-drug-treated animals, was observed at all time periods. The general trend for infected control animals was a decrease in colony numbers. All mice given CY plus 10(7) yeast cells intravenously (i.v.) died by day 20 postinfection. Mice given CY and 10(7) yeast cells i.p. showed no evidence of fatal Histoplasma infection. Deaths occurring by day 5 in CY-treated animals injected with H. capsulatum yeast cells i.v. or i.p. were considered due to bacterial infection or toxicity, or both. Hepatosplenomegaly was observed in mice treated with CY and 10(7) yeast cells of H. capsulatum. Enlarged lungs were also noted. CY control mouse spleens weighed 30% less than normal spleens. Organs of animals injected with H. capsulatum alone did not vary significantly from those of normal mice. Complete drug-induced suppression of humoral antibody response was achieved for 10 days, as determined by hemagglutination titrations. 相似文献
993.
994.
Reda M. El-S. Hassanine Mohammed O. Al-Jahdali 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(3):289-295
During June and July of 2007, a total of 130 specimens of the fish Rastrelliger kanagurta Cuvier (Teleostei, Scombridae), ranging between 19–31 cm in total length, were caught in the Red Sea off the coast of Sharm
El-Sheikh, South Sinai, Egypt, and examined for infections by acanthocephalans (65 fish/month). Of this number, 29 (22.30%)
were slightly or heavily parasitized by the acanthocephalan Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 (Cavisomidae); no other helminth parasites were found in the intestine of R. kanagurta. Twenty-nine infrapopulations of D. nudus, ranging from 23–218 individuals were collected from the infected fishes. These infrapopulations were distributed in a well-defined
fundamental niche along the intestine of R. kanagurta, where the distribution of male worms was not random with respect to female worms size and position and suggests that the
male-male competition for access to female may be intense and may select for large males. No correlation between fish size
and infrapopulation size was observed. Correlations between female-to-male sex ratio and infrapopulation size, numbers of
females and their mean lengths, numbers of males and their mean lengths, mean female length and mean male length within infrapopulation
were very strong, and clearly suggest that as the infrapopulation size increased, the number of females and their mean lengths
decreased and the number of males and their mean lengths increased. Combination of these results strongly suggests density-dependent
effects and competition between male worms. The relationship between the mean female length or size and the number of eggs
within its pseudocoel was strongly positive; egg production by female worm significantly decreases as the infrapopulation
size increases, suggesting density-dependent reduction in female worm fecundity. Tendency for the variability in male testes
size was not significant in infrapopulations of D. nudus. All of these results are discussed. 相似文献
995.
Juan Tentoni Nélida Nora Polini Emma Beatriz Casanave 《Comparative clinical pathology》2008,17(3):193-196
The fibrinolytic mechanism in the armadillo Chaetophractus villosus (Mammalia, Xenarthra, Dasypodidae) quite unknown until now was studied. Results were compared with those corresponding to
healthy adult human beings. Whole blood lysis time and diluted blood lysis time were not detectable in armadillos. Euglobulin
clot lysis time and plasminogen activity (Plg) were lower than in healthy humans. We established the presence of the fibrinolytic
system in Ch. villosus through the measurement of fibrin fibrinogen degradation products. The activity of the plasminogen activator inhibitor was
two to four times greater than in healthy humans. The activity of the alpha 2 anti-plasmin (α2AP) was similar and displaced
toward lower values. The Plg/α2AP relation was lower. The results obtained suggest that Ch. villosus has a hypercoagulable and hypofibrinolytic profile. Our findings are not only the first contribution to elucidate the physiology
of the fibrinolytic system in Xenarthra but also contribute to develop an animal model for studies in haemostasis and thrombosis. 相似文献
996.
Attila Patocs Peter Gergics Katalin Balogh Miklos Toth Ferenc Fazakas Istvan Liko Karoly Racz 《BMC medical genetics》2008,9(1):29
Von Hippel-Lindau disease (VHL) is a rare autosomal dominant disease characterized by development of cystic and tumorous lesions
at multiple sites, including the brain, spinal cord, kidneys, adrenals, pancreas, epididymis and eyes. The clinical phenotype
results from molecular abnormalities of the VHL tumor suppressor gene, mapped to human chromosome 3p25-26. The VHL gene encodes two functionally active VHL proteins due to the presence of two translational initiation sites separated by
53 codons. The majority of disease-causing mutations have been detected downstream of the second translational initiation
site, but there are conflicting data as to whether few mutations located in the first 53 codons, such as the Pro25Leu could
have a pathogenic role. In this paper we report a large Hungarian VHL type 2 family consisting of 32 members in whom a disease-causing
AGT80AAT (Ser80Ile) c.239G>A, p.Ser80Ile mutation, but not the concurrent CCT25CTT (Pro25Leu) c.74C>T, p.Pro25Leu variant
co-segregated with the disease. To our knowledge, the Ser80Ile mutation has not been previously described in VHL type 2 patients
with high risk of pheochromocytoma and renal cell cancer. Therefore, this finding represents a novel genotype-phenotype association
and VHL kindreds with Ser80Ile mutation will require careful surveillance for pheochromocytoma. We concluded that the Pro25Leu
variant is a rare, neutral variant, but the presence such a rare gene variant may make genetic counseling difficult. 相似文献
997.
F Ito E F Hunter R W George B L Swisher S A Larsen 《Journal of clinical microbiology》1991,29(3):444-448
To date, tissue sections prepared from Formalin-fixed tissues have not been successfully stained with Treponema pallidum subspecies-specific antibody in a direct fluorescent-antibody assay. While current methods stain T. pallidum, they do not distinguish T. pallidum from other spirochetes such as Borrelia burgdorferi (E. F. Hunter, P. W. Greer, B. L. Swisher, A. R. Simons, C. E. Farshy, J. A. Crawford, and K. R. Sulzer, Arch. Pathol. Lab. Med. 108:878-880, 1984). Because trypsin pretreatment of tissue sections has enhanced other immunofluorescent-antibody (IFA) applications, we compared the use of the trypsin digestion method with the current 1% ammonium hydroxide (NH4OH) method as a means to obtain specific staining of T. pallidum in tissues by both direct and indirect IFA techniques. Pretreated T. pallidum-infected tissues sections from rabbits, hamsters, and humans were quantitatively examined with the direct fluorescent-antibody-T. pallidum test conjugate absorbed with Treponema phagedenis, the Reiter treponeme. For indirect staining, a serum specimen from a patients with syphilis absorbed by affinity chromatography with T. phagedenis was used as the primary reagent, and a fluorescein isothiocyanate-labeled rabbit anti-human globulin was used as the secondary reagent. Serum specificity was established first by examining antigen smears of T. pallidum subsp. pallidum, T. pallidum subsp. pertenue, B. burgdorferi, T. phagedenis, and Treponema denticola MRB and then by examining tissues infected with these pathogens plus those infected with four Leptospira serovars. When we stained tissue using the direct IFA method that is currently a standard method for the examination of chancre smears, we found it to be unsuitable for use with tissue. Trypsin digestion did not offer an improvement over the NH4OH pretreatment method in the specific identification of T. pallidum by direct IFA. However, specific identification of T. pallidum in tissue sections was obtained by the indirect IFA technique after either trypsin or NH4OH pretreatment. 相似文献
998.
Efficient genetic analysis of large exonic regions containing heterozygous mutations and common polymorphisms can be difficult. We have analyzed 30 patients for inherited susceptibility mutations (ISM) within exon 11 of the BRCA1 gene as part of an ongoing genetic epidemiological study of high-risk breast cancer (HRBC). A novel combination of restriction endonuclease fingerprinting (REF) and conformation sensitive gel electrophoresis (CSGE) was developed for rapid and efficient screening of mutations. This method (REF-CSGE) was compared side-by-side with standard CSGE and evaluated for both efficiency and sensitivity of detection. REF-CSGE detected 100% of the alterations found by CSGE. However, one variant was only detectable by REF-CSGE. All samples with variant bands were sequenced to confirm the nature of the alteration. In total, two small deletions (frameshifts) and 62 point mutations (60 known polymorphisms and two variants of unknown significance) were found in our cohort. The majority of the exon 11 polymorphisms detected are inherited as a linked haplotype. Point mutations that comprise these haplotypes could be simultaneously detected on a single gel by REF-CSGE, thereby decreasing the number of sequencing reactions necessary to elucidate heteroduplex patterns seen on CSGE gels. An analysis of the overall efficiency of both techniques revealed that REF-CSGE required 67% fewer confirmatory sequencing reactions, resulting in savings in both reagents and technician time. 相似文献
999.
Jamie Dollahite Wene George M. Barnwell Daniel S. Mitchell 《Physiology & behavior》1982,28(3):569-573
To evaluate the influence of flavor on ad lib consumption and on associated changes in body weight, female baboons, 7–15 years of age, served in two experiments with seven monkey chows which were identical except for flavor: lemon, orange, apple, sugar, fruit punch, chocolate, and unflavored. In the first experiment, two groups of animals (n=7 and 4) received five of the seven flavors, presented in daily pair-wise combinations. Analysis of quantities consumed demonstrated marked and consistent flavor preferences in individual baboons. Although specific preference varied between animals, total amounts consumed of the various flavors differed significantly, with rank ordering clearly evident. Overall food intake and body weights increased significantly over baseline values obtained with a standard, unflavored chow. In the second experiment, three baboons received chow of a preferred flavor for nine weeks. Amounts consumed and body weights increased significantly over baseline. These results indicate that flavored chows may be useful for producing a nonhuman primate behavioral model of obesity and for inducing animals to eat otherwise unpalatable diets. 相似文献
1000.
In order to establish referential hematological parameters, blood samples were taken from 100 healthy specimens of the Argentine
tegu lizard (Tupinambis merianae) by means of venipuncture of ventral coccigeal vein. The determination of red blood cells, leukocyte and thrombocyte count,
hematocrit, hemoglobin concentration, hematometric index and differential leukocyte count were performed, and compared with
other saurian species. No statistically significant changes were observed as function as sex and age (p > 0.01). During winter, high values of red blood cell counts, hematocrit and hemoglobin were observed (p < 0.01), while in summer significantly increased leukocyte and thrombocyte counts were observed (p < 0.01). The differential leukocyte counts were not affected by the studied factors. 相似文献