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21.
Alicia A. Gil de Pertierra 《Zoologischer Anzeiger》2005,243(4):307-304
The surface of the tegument of the scolex and the immature proglottides of Monticellia belavistensis, M. ventrei, Nomimoscolex chubbi, and N. lopesi is described using scanning electron microscopy. Only blade-like spiniform microtriches and filiform microtriches were observed in the species studied. The types, size and density of microtriches on the apical region surface of the scolex, central cavity surface of suckers, marginal ring surface of suckers, non-adherent surface of suckers, proliferation zone surface, and immature proglottis surface were compared among these species. The distribution pattern of the microtriches was not a reliable feature to discriminate among the genera considered in this study. It varied in each of the species of Monticellia examined, and did not permit to split the heterogeneous genus Nomimoscolex. However, the microthrix pattern can be regarded as an additional diagnostic feature to distinguish among species of proteocephalideans. Further comparative research involving other species of proteocephalid taxa is needed to elucidate the systematic value of the tegumental morphology. 相似文献
22.
C A Kappel M C Dal Canto R W Melvold B S Kim 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(12):4322-4326
Intracerebral inoculation of susceptible mice with Theiler's murine encephalomyelitis virus induces a demyelinating disease that is similar to human multiple sclerosis. This murine model for human multiple sclerosis is apparently immune-mediated and the genes involved in the immune response influence the outcome of disease susceptibility as observed with human multiple sclerosis. These genes include the MHC and TCR genes. However, the functional relationships among these genes on the disease susceptibility has not yet been studied. In this study, we demonstrate that the effect of the H-2s genotype from susceptible SJL/J mice overrides the resistant effect of the BALB/c TCR beta-chain gene in CXJ recombinant-inbred and BALB.S congenic mice. These results strongly suggest the presence of a hierarchy of genes involved in the immune response in Theiler's murine encephalomyelitis virus-induced demyelinating disease. 相似文献
23.
Serum proteins [molecular weight (MW) > 10,000] are essential for increased insulin-stimulated glucose transport after in vitro muscle contractions. We investigated the role of the kallikrein-kininogen system, including bradykinin, which is derived from kallikrein (MW > 10,000)-catalyzed degradation of serum protein kininogen (MW > 10,000), on this contraction effect. In vitro electrical stimulation of rat epitrochlearis muscles was performed in 1) rat serum +/- kallikrein inhibitors; 2) human plasma (normal or kallikrein-deficient); 3) rat serum +/- bradykinin receptor-2 inhibitors; or 4) serum-free buffer +/- bradykinin. 3-O-methylglucose transport (3-MGT) was measured 3.5 h later. Serum +/- kallikrein inhibitors tended (P = 0.08) to diminish postcontraction insulin-stimulated 3-MGT. Contractions in normal plasma enhanced insulin-stimulated 3-MGT vs. controls, but contractions in kallikrein-deficient plasma did not. Supplementing rat serum with bradykinin receptor antagonist HOE-140 during contraction did not alter insulin-stimulated 3-MGT. Muscles stimulated to contract in serum-free buffer plus bradykinin did not have enhanced insulin-stimulated 3-MGT. Bradykinin was insufficient for postcontraction-enhanced insulin sensitivity. However, results with kallikrein inhibitors and kallikrein-deficient plasma suggest kallikrein plays a role in this improved insulin action. 相似文献
24.
We have compared the species richness of medicinal plants and the differential patterns of use amongst settlements in the
Andean communities of Northwest Argentina which have differing levels of isolation. About 259 ethnoespecies, belonging to
74 plant families, were included, representing between 70 and 80% of the total estimate. The results indicate that Coronopus didymus is the most relevant and important species. The method of use of medicinal plants and the ailments treated by rural doctors compared to those of the layperson is different. Native and exotic plants are used differently according to the body system
treated. There are some relationships between internal and external use and body systems and recipes. The greater medicinal
species richness found in the less isolated locations is due to external enriching cultural influences. 相似文献
25.
W J Allard C D Cheli D L Morris J Goldblatt Y Pierre L Kish Y Chen J Dai R L Vessella D W Chan M K Schwartz Z Zhou K K Yeung 《The International journal of biological markers》1999,14(2):73-83
We conducted a multicenter evaluation of the analytical and clinical performance of the automated Bayer Immuno 1 complexed PSA (cPSA) assay, and compared assay performance to the Bayer Immuno 1 PSA assay. We sought to determine whether measurements of cPSA could be of clinical utility in the management of patients with prostate cancer. Results of the 10-day imprecision across three evaluation sites produced total CV < 2.50% and an analytical sensitivity of 0.02 microgram/L. There was an increased trend in clinical sensitivity for prostate cancer with increasing stage of disease (71-86%). Clinical specificity for patients with benign urogenital disease was 74.8%, and for other nonprostate diseases ranged from 91.1-100%. Retrospective serial monitoring of 155 patients with prostate cancer demonstrated concordance of cPSA measurements to clinical status for 97% of the patients analyzed. Results from the clinical studies using the Bayer Immuno 1 cPSA assay were comparable to results obtained with the Bayer Immuno 1 PSA assay. The Bayer Immuno 1 cPSA assay demonstrates analytical performance and clinical effectiveness in the management of prostate cancer patients during the course of disease and therapy. 相似文献
26.
Stefan Schoombie Janine Schoombie Christiaan W. Brink Kim L. Stevens Christopher W. Jones Michelle M. Risi Peter G. Ryan 《Journal of Field Ornithology》2019,90(4):361-372
The use of miniaturized video cameras to study the at‐sea behavior of flying seabirds has increased in recent years. These cameras allow researchers to record several behaviors that were not previously possible to observe. However, video recorders produce large amounts of data and videos can often be time‐consuming to analyze. We present a new technique using open‐source software to extract bank angles from bird‐borne video footage. Bank angle is a key facet of dynamic soaring, which allows albatrosses and petrels to efficiently search vast areas of ocean for food. Miniaturized video cameras were deployed on 28 Wandering Albatrosses (Diomedea exulans) on Marion Island (one of the two Prince Edward Islands) from 2016 to 2018. The OpenCV library for the Python programming language was used to extract the angle of the horizon relative to the bird’s body (= bank angle) from footage when the birds were flying using a series of steps focused on edge detection. The extracted angles were not significantly different from angles measured manually by three independent observers, thus being a valid method to measure bank angles. Image quality, high wind speeds, and sunlight all influenced the accuracy of angle estimates, but post‐processing eliminated most of these errors. Birds flew most often with cross‐winds (58%) and tailwinds (39%), resulting in skewed distributions of bank angles when birds turned into the wind more often. Higher wind speeds resulted in extreme bank angles (maximum observed was 94°). We present a novel method for measuring postural data from seabirds that can be used to describe the fine‐scale movements of the dynamic‐soaring cycle. Birds appeared to alter their bank angle in response to varying wind conditions to counter wind drift associated with the prevailing westerly winds in the Southern Ocean. These data, in combination with fine‐scale positional data, may lead to new insights into dynamic‐soaring flight. 相似文献
27.
Gaute W. Seljestad María Quintela Ellika Faust Kim T. Halvorsen Franois Besnier Eeva Jansson Geir Dahle Halvor Knutsen Carl Andr Arild Folkvord Kevin A. Glover 《Ecology and evolution》2020,10(12):6120-6135
Capture and long‐distance translocation of cleaner fish to control lice infestations on marine salmonid farms has the potential to influence wild populations via overexploitation in source regions, and introgression in recipient regions. Knowledge of population genetic structure is therefore required. We studied the genetic structure of ballan wrasse, a phenotypically diverse and extensively used cleaner fish, from 18 locations in Norway and Sweden, and from Galicia, Spain, using 82 SNP markers. We detected two very distinct genetic groups in Scandinavia, northwestern and southeastern. These groups were split by a stretch of sandy beaches in southwest Norway, representing a habitat discontinuity for this rocky shore associated benthic egg‐laying species. Wrasse from Galicia were highly differentiated from all Scandinavian locations, but more similar to northwestern than southeastern locations. Distinct genetic differences were observed between sympatric spotty and plain phenotypes in Galicia, but not in Scandinavia. The mechanisms underlying the geographic patterns between phenotypes are discussed, but not identified. We conclude that extensive aquaculture‐mediated translocation of ballan wrasse from Sweden and southern Norway to western and middle Norway has the potential to mix genetically distinct populations. These results question the sustainability of the current cleaner fish practice. 相似文献
28.
29.
Blocking of acidosis-mediated apoptosis by a reduction of lactate dehydrogenase activity through antisense mRNA expression. 总被引:3,自引:0,他引:3
D Jeong T S Kim J W Lee K T Kim H J Kim I H Kim I Y Kim 《Biochemical and biophysical research communications》2001,289(5):1141-1149
Lactic acid produced from the cells is a potential cause of extra- and intracellular acidification. Due to scarce technical tools, lactic acid that leads to acidification could not be reduced and direct evidence of the relationship between metabolic lactate and apoptosis has not yet been elucidated. In this study, we designed a cellular pH regulation system in CHO cells by a reduction of lactate dehydrogenase (LDH) activity through LDH antisense mRNA expression. This inhibited lactate production and, therefore, acidification of the cytosol. Under HCO3(-)-buffered growth conditions, both the parent CHO cells and the engineered CHO cells maintained their extracellular pH and intracellular pH fairly well. However, upon acidification of the cytosol, only the parent CHO cells underwent apoptosis under HCO3(-)-free conditions. In fact, we observed a number of apoptosis-related events only in control cells, including mitochondrial dysfunction, cytochrome c release, and an increase in caspase-3 enzymatic activity. 相似文献
30.