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1.
2.
Frans P. Houwen Jeannette Plokker Alfons J. M. Stams Alexander J. B. Zehnder 《Archives of microbiology》1990,155(1):52-55
Enzyme measurements were carried out with crude cell-free extracts of the propionate oxidizing coculture of Syntrophobacter wolinii and Desulfovibrio G11. Using cell-free extracts of a pure culture of Desulfovibrio G11 as a blank, most of the enzymes involved in the methylmalonyl-CoA pathway for propionate oxidation, including a propionyl-CoA: oxaloacetate transcarboxylase, were demonstrated in S. wolinii. 相似文献
3.
Mansoor N. Saleh Albert F. LoBuglio Richard H. Wheeler Kimberly J. Rogers Amy Haynes Jeannette Y. Lee M. B. Khazaeli 《Cancer immunology, immunotherapy : CII》1990,32(3):185-190
Summary A group of 15 patients with metastatic colorectal adenocarcinoma received a combination of interferon (0.1 mg/m2, days 1–15) and the murine monoclonal antibody 17-1A (400 mg, days 5, 7, 9 and 12). The treatment was tolerated with minimal toxicity. Of the 14 evaluable patients, 13 developed human antibody to murine 17-1A, with 11 patients demonstrating antibody to the variable region of 17-1A (anti-idiotype). Antibody to the variable region was inhibited by 17-1A but not by mouse immunoglobulin. Sera from patients with substantial anti-idiotype reactivity were capable of inhibiting the binding of murine 17-1A to antigen expressing LS174-T cells thus indicating the presence of antibody directed against the 17-1A combining site (mirror-image anti-idiotype). The median survival of the whole group was 56 weeks and there was no correlation between clinical response/survival and the development of anti-idiotype antibody.Supported by the Veterans Administration Medical Center and by Public Health Services grant CA 45 232 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services 相似文献
4.
The epidermis of Drosophila has a tissue polarity that is manifested by a parallel array of polarized structures (primarily hairs and bristles). The production of normal tissue polarity requires the function of the frizzled (fz) locus. We have isolated a large number of alleles at this locus and have phenotypically characterized more than 25 of them. We have found extensive allelic variation that a previous study failed to detect. Most of the alleles fall into a hypomorphic to amorphic series. Two alleles, however, have unusual properties. These alleles, which in general are moderately strong alleles, fail to produce a rough eye phenotype that is characteristic of all the other moderate or strong fz alleles. Thus, these two alleles are tissue specific in effect. Furthermore, these two alleles also have a neomorphic or antimorphic effect on hair polarity in one region of the wing. 相似文献
5.
Donna K. Stafford Garrett W. Milliken Jeannette P. Ward 《Primates; journal of primatology》1990,31(3):407-414
Lateralized hand use in gibbons was assessed for both food reaching and leading limb in brachiation. Sex and age effects were
found in hand preference for food reaching. Adult females were all very strongly right hand preferent, whereas adult males
had no across group consistent preference. Within the female group there was a strong correlation between age and strength
of right handedness. When compared in terms of absolute strength of hand preference, females were found to be more strongly
lateralized than males. Leading limb preference in brachiation was scored into vocal and non-vocal categories. Three subjects
had a shift in preferred leading limb from the non-vocal brachiation condition to the vocal brachiation condition. This shift
may be influenced by the arousal effects of species typical vocalization. The results of this study underline the importance
of consideration of such factors as sex and age when interpreting behavioral lateralization data. The exploration of laterality
in many different response measures is important to the achievement of a complete understanding of behavioral lateralization
in primates. 相似文献
6.
Jeannette Reinartz Jutta Link Robert F. Todd Michael D. Kramer 《Experimental cell research》1994,214(2)
It is assumed that plasmin participates in pericellular proteolysis in the epidermis. Plasmin is generated by keratinocyte-associated plasminogen activators from the proenzyme plasminogen; plasminogen activation can proceed at the keratinocyte surface. The resultant plasmin interferes with cell to matrix adhesion and does possibly contribute to keratinocyte migration during reepithelialization. Here we describe the receptor for urokinase-type plasminogen activator (uPA-R) in the human keratinocyte cell line HaCaT, which serves to direct plasminogen activation to the cell surface; we relate the receptor to the uPA-R previously described in human myclo-/monocytes. Binding of uPA to the receptor accelerated plasminogen activation by a factor of ≈10, compared to uPA in solution. Receptor-bound uPA was susceptible to inhibition by the plasminogen activator inhibitors 1 and 2. uPA and uPA-R antigen, as well as uPA activity, were localized to the leading front of expanding sheets of HaCaT cells. Exposure of HaCaT cells to plasminogen was followed by detachment of the cells. Detachment was prevented by an anti-catalytic anti-uPA antibody, by the plasmin-specific inhibitor aprotinin, and by the lysine analogue tranexamic acid, the latter of which prevents plasmin(ogen) binding to the cell surface. Our findings support the hypothesis that uPA-mediated plasminogen activation is characteristic of mobile rather than sessile keratinocytes. Moreover, the uPA-R seems to focalize plasminogen activation to the surface of cells at the site of keratinocyte migration. 相似文献
7.
Effects of modeling and lineage on fishing behavior in the small-eared bushbaby (otolemur garnettii)
Sheree L. Watson Martha Schiff Jeannette P. Ward 《International journal of primatology》1994,15(4):507-519
Thirty-eight bushbabies(Otolemur garnettii)were subjects in an observational learning study. We exposed them to one of three modeling conditions: (1) fishing model—one
that actually performed fishing behavior; (2) nonfishing model—one that performed as a model in every way except performance
of fishing behavior; and (3) no model. We assessed them with regard to latency to approach the fishbowl, latency to make an
initial fishing attempt, duration of time spent in the vicinity of the fishbowls, and number of actual fishing attempts. Results
indicate that subjects that were exposed to either fishing or nonfishing models were faster to approach the fishbowls and
spent more time in the vicinity of the fishbowls than animals in the no-model condition Lineage, i.e., whether or not the
animals’ parents fished, rather than modeling condition, was the best predictor of the latency to initial fishing attempt
and the number of attempts made. 相似文献
8.
Submaximal,aerobic exercise training exacerbates the cardiomyopathy of postweanling Cu-depleted rats
Jeannette Davidson Denis M. Medeiros Robert L. Hamlin James E. Jenkins 《Biological trace element research》1993,38(3):251-272
To determine the dual effect of exercise training and copper depletion on myocardial function and ultrastructure, postweanling
rats were either trained or sedentary while fed copper-adequate or copper-deficient diets for 8 wk. Rats developed characteristic
myocardial subcellular degeneration and increased cardiac mitochondrial volume density when copper depleted, despite lack
of overt cardiac hypertrophy, hypertension, or anemia. Training combined with copper depletion induced mild left ventricular
hypertrophy. Basal laminae appeared fractionated in areas at capillary-myocyte interface, with focal pericapillary and interstitial
collagen accumulation, where-as overt fibrosis was absent or minimal. Electrocardiograms revealed increased QRS wave and QT
duration and notching of QRS complex with copper depletion, consistent with intraventricular conductance disturbances. The
oxidative capacity of soleus muscle increased with training in copper-adequate rats, but was reduced with progressive copper
depletion. These data suggest that copper depletion and training are synergistic in effecting focal accumulation of collagen,
with deleterious effect on exercise capacity. 相似文献
9.
Martin Gael Oyono Sebastien Kenmoe Ngu Njei Abanda Guy Roussel Takuissu Jean Thierry Ebogo-Belobo Raoul Kenfack-Momo Cyprien Kengne-Nde Donatien Serge Mbaga Serges Tchatchouang Josiane Kenfack-Zanguim Robertine Lontuo Fogang Elisabeth Zeukoo Menkem Juliette Laure Ndzie Ondigui Ginette Irma Kame-Ngasse Jeannette Nina Magoudjou-Pekam Arnol Bowo-Ngandji Seraphine Nkie Esemu Lucy Ndip 《PLoS neglected tropical diseases》2022,16(7)
Yellow fever (YF) has re-emerged in the last two decades causing several outbreaks in endemic countries and spreading to new receptive regions. This changing epidemiology of YF creates new challenges for global public health efforts. Yellow fever is caused by the yellow fever virus (YFV) that circulates between humans, the mosquito vector, and non-human primates (NHP). In this systematic review and meta-analysis, we review and analyse data on the case fatality rate (CFR) and prevalence of YFV in humans, and on the prevalence of YFV in arthropods, and NHP in sub-Saharan Africa (SSA). We performed a comprehensive literature search in PubMed, Web of Science, African Journal Online, and African Index Medicus databases. We included studies reporting data on the CFR and/or prevalence of YFV. Extracted data was verified and analysed using the random effect meta-analysis. We conducted subgroup, sensitivity analysis, and publication bias analyses using the random effect meta-analysis while I2 statistic was employed to determine heterogeneity. This review was registered with PROSPERO under the identification CRD42021242444. The final meta-analysis included 55 studies. The overall case fatality rate due to YFV was 31.1% (18.3–45.4) in humans and pooled prevalence of YFV infection was 9.4% (6.9–12.2) in humans. Only five studies in West and East Africa detected the YFV in mosquito species of the genus Aedes and in Anopheles funestus. In NHP, YFV antibodies were found only in members of the Cercopithecidae family. Our analysis provides evidence on the ongoing circulation of the YFV in humans, Aedes mosquitoes and NHP in SSA. These observations highlight the ongoing transmission of the YFV and its potential to cause large outbreaks in SSA. As such, strategies such as those proposed by the WHO’s Eliminate Yellow Fever Epidemics (EYE) initiative are urgently needed to control and prevent yellow fever outbreaks in SSA. 相似文献
10.
Jeannette C. Miller 《Journal of neurochemistry》1990,54(4):1453-1455
The effect of selective dopamine D2 receptor-acting drugs on striatal c-fos mRNA expression in the rat has been investigated by Northern hybridization and autoradiography to determine a possible role for c-fos in the initiation of adaptive changes in D2 receptor number by neuroleptic drugs. The neuroleptic drug haloperidol, a D2 receptor antagonist, was found to produce a rapid and transient induction of c-fos mRNA expression as compared with the expression in animals treated with saline. This induction by haloperidol was found to be dose dependent and D2 receptor mediated, inasmuch as a D2 agonist completely reversed the induction and the inactive isomer of the neuroleptic butaclamol, which does not produce an increase in D2 receptors, had no effect on c-fos mRNA expression. From these data, it can be concluded that c-fos expression in striatum is under dopamine D2 receptor-mediated inhibitory control. It is suggested that c-fos may play a role in the initiation of the increase in D2 receptor number produced by chronic neuroleptic drug treatment. 相似文献