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61.
Carbohydrates have been suggested to account for some IgE cross- reactions
between various plant, insect, and mollusk extracts, while some IgG
antibodies have been successfully raised against plant glycoproteins. A rat
monoclonal antibody raised against elderberry abscission tissue (YZ1/2.23)
and rabbit polyclonal antiserum against horseradish peroxidase were
screened for reactivity in enzyme-linked immunosorbent assay against a
range of plant glycoproteins and extracts as well as neoglycoproteins, bee
venom phospholipase, and several animal glycoproteins. Of the
oligosaccharides tested, Man3XylFucGlcNAc2(MMXF3) derived from horseradish
peroxidase was the most potent inhibitor of the reactivity of both YZ1/2.23
and anti- horseradish peroxidase to native horseradish peroxidase
glycoprotein. The reactivity of YZ1/2. 23 and anti-horseradish peroxidase
against Sophora japonica lectin was most inhibited by a neoglycoconjugate
of bromelain glycopeptide cross-linked to bovine serum albumin, while the
defucosylated form of this conjugate was inactive as an inhibitor. A wide
range of plant extracts was found to react against YZ1/2.23 and
anti-horseradish peroxidase, with particularly high reactivities recorded
for grass pollen and nut extracts. All these reactivities were inhibitable
with the bromelain glycopeptide/bovine serum albumin conjugate. Bee venom
phospholipase and whole bee venom reacted weakly with YZ1/2.23 but more
strongly with anti-horseradish peroxidase in a manner inhibitable with the
bromelain glycopeptide/bovine serum albumin conjugate, while hemocyanin
from Helix pomatia reacted poorly with YZ1/2.23 but did react with
anti-horseradish peroxidase. It is concluded that the alpha1, 3-fucose
residue linked to the chitobiose core of plant glycoproteins is the most
important residue in the epitope recognized by the two antibodies studied,
but that the polyclonal anti-horseradish peroxidase antiserum also contains
antibody populations that recognize the xylose linked to the core mannose
of many plant and gastropod N-linked oligosaccharides.
相似文献
62.
63.
Single-copy nuclear DNAs (scnDNAs) of eight species of arvicoline and six
species of murine rodents were compared using DNA-DNA hybridization. The
branching pattern derived from the DNA comparisons is congruent with the
fossil evidence and supported by comparative biochemical, chromosomal, and
morphological studies. The recently improved fossil record for these
lineages provides seven approximate divergence dates, which were used to
calibrate the DNA-hybridization data. The average rate of scnDNA divergence
was estimated as 2.5%/Myr. This is approximately 10 times the rate in the
hominoid primates. These results agree with previous reports of accelerated
DNA evolution in muroid rodents and extend the DNA-DNA hybridization data
set of Brownell.
相似文献
64.
Dogs, in the age range 1–3 years old, were randomly selected from the largest animal insurance database in Sweden for inclusion in the study. The study was performed in 1997, and a total of 680 dog owners were selected for the study. A total of 461 dog owners completed the survey, at an overall response rate of 68%. Data was compared to a recent gallup performed on a sample of all dogs in Sweden. The demographic statistics of the insured dog population were in many aspects similar to the total dog population of Sweden. Typical for both insured dogs and the total population of dogs were a low proportion of neutered dogs, that many dogs were bought at an early age, that many dogs were in contact with a "breeder" when sold, and a similar profile of health status. However, "dog breeders" seemed to have their dogs insured to a higher extent than the general dog owner. It was concluded that as the populations were alike in many respects, it is reasonable to use the insurance database for epidemiological studies on diet and exercise in Swedish dogs. 相似文献
65.
Brian P Halliday Richard JE Skipworth Lucy Wall Hamish A Phillips Graeme W Couper Andrew C de Beaux Simon Paterson-Brown 《International Seminars in Surgical Oncology : ISSO》2007,4(1):24
Background
Oesophageal cancer is a major clinical problem with a generally poor prognosis. As a result there has been interest in combining surgery with neoadjuvant chemotherapy to try and improve outcomes, although the current evidence for benefit is inconsistent. We aimed to compare, in a non-randomised study, the post-operative complication rate and short and long-term survival of patients who underwent surgical resection for carcinoma of the oesophagus and types I and II carcinoma of the oesophago-gastric junction with or without neo-adjuvant chemotherapy.Methods
Details of all resections for oesophageal/junctional (types I and II) adenocarcinoma or squamous cell carcinoma between April 2000 and July 2006 were collected prospectively. Data from patients with T3 and/or N1 disease who underwent either neoadjuvant chemotherapy (NAC) or not (non-NAC) were compared. Data were analysed using Kaplan-Meier plots, Mann-Whitney U-test, Cox Regression modelling, and Chi-squared test with Yates' correction where sample sizes <10.Results
167 patients were included (89 NAC and 78 non-NAC). The in-hospital post-operative mortality rate of the NAC group (n = 2 deaths; 2.2%) was significantly lower (p = 0.045) than the non-NAC group (n = 6 deaths; 7.7%). Most deaths were due to cardio-respiratory complications; however, there was no significant difference in rates of chest infections, anastomotic leaks, wound infections, re-operations, readmission to ITU or overall complications between the two groups. Although both the two-year survival rate (60.7%) and long-term survival of NAC patients (median survival = 793 days; 95% CI = 390–1196) was greater than non-NAC patients (two-year survival rate = 48.7%; median survival = 554 days; 95% CI = 246–862 respectively), these differences were not statistically significant.Conclusion
This non-randomised study demonstrated that NAC was associated with a significant reduction in post-operative inpatient mortality rate. Whether this can be explained by a decreased co-morbidity in NAC patients or a protective phenomenon associated with NAC remains unclear. This study also demonstrated a greater two-year survival rate and overall median survival time following NAC but this was not statistically significant.66.
Background
Like other vertebrates, primates recognize their relatives, primarily to minimize inbreeding, but also to facilitate nepotism. Although associative, social learning is typically credited for discrimination of familiar kin, discrimination of unfamiliar kin remains unexplained. As sex-biased dispersal in long-lived species cannot consistently prevent encounters between unfamiliar kin, inbreeding remains a threat and mechanisms to avoid it beg explanation. Using a molecular approach that combined analyses of biochemical and microsatellite markers in 17 female and 19 male ring-tailed lemurs (Lemur catta), we describe odor-gene covariance to establish the feasibility of olfactory-mediated kin recognition. 相似文献67.
68.
69.
Debra J. Hazen-Martin Betty I. Tarnowski John H. Todd Mary Ann Sens John E. Bylander Brendan J. Smyth A. Julian Garvin Donald A. Sens 《In vitro cellular & developmental biology. Animal》1994,30(6):356-365
Summary Cell cultures were initiated from seven human fetal kidneys that varied in gestational age from 90 days to newborn. The growth
medium utilized was a 1:1 mixture of Dulbecco’s modified Eagle’s and Ham’s F12 supplemented with selenium (5 ng/ml), insulin
(5μg/ml), transferrin (5μg/ml), hydrocortisone (36 ng/ml), triiodothyronine (4 pg/ml), and epidermal growth factor (10 ng/ml). For all the kidney isolates,
initial cell attachment occurred within 12 h through multicell spheroids, and by 24 h a rapidly growing population of cells
was obtained. Confluency was reached within 3 to 6 days. A combination of light microscopy, immunohistochemistry, and ultrastructural
evaluation was utilized to characterize the resulting cultures as epithelial and homogeneous within each isolate and among
the isolates. That is, regardless of gestational age of the fetal kidney used as starting material, an identical or highly
similar population of cells was obtained. By light microscopy, the cultures were noted to form very few domes, the number
being an indication of transport activity. However, ultrastructural examination revealed that the cells were noted to form
domes composed of only a few cells or “micro-domes” that would not be visible by light microscopy. Within the micro-domes
as well as other areas of the monolayer an apparent absence of tight junctions was noted by routine transmission electron
microscopy. However, by freeze fracture analysis cells were shown to possess sealing strands, the structural component of
tight junctions. It is postulated that the tight junctions of fetal epithelial cells are structurally altered as compared
to tight junctions in adult renal epithelial cell cultures. 相似文献
70.
Cyclins are indispensable elements of the cell cycle and derangement of their function can lead to cancer formation. Recent studies have also revealed more mechanisms through which cyclins can express their oncogenic potential. This review focuses on the aberrant expression of G1/S cyclins and especially cyclin D and cyclin E; the pathways through which they lead to tumour formation and their involvement in different types of cancer. These elements indicate the mechanisms that could act as targets for cancer therapy. 相似文献