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11.
A. W. Asscher M. Sussman W. E. Waters Joy A. S. Evans H. Campbell K. T. Evans J. Edmund Williams 《BMJ (Clinical research ed.)》1969,1(5647):804-806
Short courses of nitrofurantoin and ampicillin produced an immediate cure in 80% of adult non-pregnant bacteriuric women. Of the subjects so treated, 55% remained cured at the end of one year. Over the same follow-up period 36% of untreated bacteriuric women developed a spontaneous remission of bacteriuria. Treatment failed to prevent the development of symptomatic infection, and the reinfections which followed successful treatment were more commonly associated with the development of symptoms than the persistent or relapsing infections in untreated or unsuccessfully treated subjects.It is concluded that a search for bacteriuria in non-pregnant women is unlikely to be of value as a preventive measure, since in many instances it fails to detect urinary tract infection at an early stage and since treatment by methods suitable for large-scale use is ineffective. 相似文献
12.
The carnitine-independent oxidation of palmitate plus malate by moth flight-muscle mitochondria 总被引:2,自引:2,他引:0
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Edmund Stevenson 《The Biochemical journal》1968,110(1):105-110
Mitochondria isolated from the flight muscle of the southern armyworm moth, Prodenia eridania, can oxidize palmitate+malate very rapidly. Added carnitine had no effect on the rate of oxidation of palmitate+malate by flight-muscle mitochondria from two species of moths, and carnitine palmitoyltransferase could not be detected in Prodenia by direct assay. Palmitoylcarnitine was not oxidized by moth mitochondria, but when added in low concentrations it reversibly suppressed the oxidation of palmitate. The evidence indicates that carnitine is not involved in fatty acid degradation by moth flight muscle. Added thiols, including CoA, also suppressed palmitate+malate oxidation. An ATP-dependent fatty acyl-CoA synthetase is present in moth mitochondria. 相似文献
13.
The effect of focused high energy microwave treatment (MW) on brain concentrations and molecular forms of substance P, neurokinin A, neuropeptide Y, neurotensin, galanin and calcitonin gene-related peptide was investigated. Groups of rats were treated as follows: 1) MW, storage for 60 min at 22°C, 2) Decapitation, storage for 60 min at 22°C, 3) Decapitation, storage for 60 min at 22°C, MW treatment, 4) MW, decapitation, storage for 2 min at 22°C and 5) Decapitation, storage for 2 min at 22°C. Peptide concentrations were in all instances highest in the MW sacrificed groups. MW increased the concentration of intact peptides by rapid inhibition of peptidase activity and increase in peptide solubility/extractability. 相似文献
14.
中国蝾螈科动物的反捕行为(正文) 总被引:1,自引:0,他引:1
中国的蝾螈科(Family Salamandridae)动物演化出了卓越的,多种多样的特征,而这些特征往往伴随着强烈的皮肤毒腺存在来保护自己免受捕食者的侵害。这些反捕食行为机制分布列入表1,并以照片解释其反捕行为,来用于已创建的定义和术语是非常重要的。这些定义和术语与不同反捕行为是密切相关的。该科中大多数蝾螈都有鲜艳的腹部色型,有皮肤分泌物毒素存在以警告捕食者。有的蝾螈,象兰尾蝾螈Cynops cyanura和中国瘰螈Paramesotriton chinensis甚至向上翻转显示腹部颜色。 相似文献
15.
In order to advance knowledge of the neural control of feeding,we investigated the cortical representation of the taste oftannic acid, which produces the taste of astringency. It isa dietary component of biological importance particularly toarboreal primates. Recordings were made from 74 taste responsiveneurons in the orbitofrontal cortex. Single neurons were foundthat were tuned to respond to 0.001 M tannic acid, and representeda subpopulation of neurons that was distinct from neurons responsiveto the tastes of glucose (sweet), NaCl (salty), HCI (sour),quinine (bitter) and monosodium glutamate (umami). In addition,across the population of 74 neurons, tannic acid was as wellrepresented as the tastes of NaCI, HCI quinine or monosodiumglutamate. Multidimensional scaling analysis of the neuronalresponses to the tastants indicates that tannic acid lies outsidethe boundaries of the four conventional taste qualities (sweet,sour, bitter and salty). Taken together these data indicatethat the astringent taste of tannic acid should be consideredas a distinct taste quality, which receives a separate representationfrom sweet, salt, bitter and sour in the primate cortical tasteareas. Chem. Senses 21: 135145, 1996. 相似文献
16.
Louis Faso Richard S. Trowbridge Wei Quan Xiu-Lan Yao Edmund C. Jenkins Alma Maciulis Thomas D. Bunch Henry M. Wisniewski 《In vitro cellular & developmental biology. Animal》1994,30(4):226-235
Summary A strain of cerebral endothelial cells was established from isolated cortical microvessels of caprine brain. These cells,
which are referred to as ECl cells, can be routinely subcultured to 32 passages without the loss of differentiated morphologic
and immunologic traits. The ability to routinely subculture ECl cells is an important asset, given that isolated cerebral
endothelial cells in mammals generally lose their differentiated traits after only 2 to 3 passages.
ECl cells were shown to contain Factor VIII-related antigen, which is a specific marker for cells of endothelial origin. ECl
cells morphologically demonstrated a scarcity of pinocytotic vesicles on their apical surfaces, a lack of trans-cytoplasmic
vesicles, and the ability to form in culture confluent monolayers with tight junctional complexes. Therefore, ECl cells possess
specific antigenic and ultrastructural features which classify them as being small vessel endothelial cells of the blood-brain
barrier type. Cytogenetic evaluation of ECl cells demonstrated a normal female goat 60,XX karyotype and confirmed the apparent
non-transformed nature of ECl cells due to the lack of chromosome abnormalities or rearrangements. Using scanning electron
microscopy, ECl cells were also shown to form confluent monolayers on mixed nitrocellulose filters, a feature that will enable
the development of an in vitro system to study trans-endothelial transport. Given that ECl cells are readily subcultured and
grow well on nitrocellulose filters, and that they resemble cerebral endothelium in vivo, it seems evident that ECl cells
can be used as a versatile model for the study of blood-brain barrier function, regulation, and pathology. 相似文献
17.
Edmund D. Brodie 《Evolution; international journal of organic evolution》1993,47(3):844-854
Quantitative genetic models of evolution rely on the genetic variance-covariance matrix to predict the phenotypic response to selection. Both prospective and retrospective studies of phenotypic evolution across generations rely on assumptions about the constancy of patterns of genetic covariance through time. In the absence of robust theoretical predictions about the stability of genetic covariances, this assumption must be tested with empirical comparisons of genetic parameters among populations and species. Genetic variance-covariance matrices were estimated for a suite of antipredator traits in two populations of the northwestern garter snake, Thamnophis ordinoides. The characters studied include color pattern and antipredator behaviors that interact to facilitate escape from predators. Significant heritabilities for all traits were detected in both populations. Genetic correlations and covariances were found among behaviors in both populations and between color pattern and behavior in one of the populations. Phenotypic means differed among populations, but pairwise comparisons revealed no heterogeneity of genetic parameters between the populations. The structure of the genetic variance-covariance matrix has apparently not changed significantly during the divergence of these two populations. 相似文献
18.
Jingru Che Thomas J. DePalma Hemamylammal Sivakumar Louisa S. Mezache Miranda M. Tallman Monica Venere Katelyn Swindle-Reilly Rengasayee Veeraraghavan Aleksander Skardal 《Biotechnology and bioengineering》2023,120(4):1108-1119
Glioblastoma (GBM) is the most common form of brain cancer. Even with aggressive treatment, tumor recurrence is almost universal and patient prognosis is poor because many GBM cell subpopulations, especially the mesenchymal and glioma stem cell populations, are resistant to temozolomide (TMZ), the most commonly used chemotherapeutic in GBM. For this reason, there is an urgent need for the development of new therapies that can more effectively treat GBM. Several recent studies have indicated that high expression of connexin 43 (Cx43) in GBM is associated with poor patient outcomes. It has been hypothesized that inhibition of the Cx43 hemichannels could prevent TMZ efflux and sensitize otherwise resistance cells to the treatment. In this study, we use a three-dimensional organoid model of GBM to demonstrate that combinatorial treatment with TMZ and αCT1, a Cx43 mimetic peptide, significantly improves treatment efficacy in certain populations of GBM. Confocal imaging was used to visualize changes in Cx43 expression in response to combinatorial treatment. These results indicate that Cx43 inhibition should be pursued further as an improved treatment for GBM. 相似文献
19.
Darja Fer
ej-Temeljotov Matev Kmet Darko Kocjan Sonja Kotnik Aleksander Resman Uro Urleb Katarina Verhnjak Igor Zver Janko
mitek 《Chirality》1993,5(4):288-292
Structure–interaction relationships, stereoselectivity, and solubility enhancement in inclusion compexation of β-cyclodextrins (CDs) with some racemic and enantiomerically pure 1,4-dihydropyridine derivatives (DHPs) were investigated. 1:1 and 1:2 (mole ratio) complexes were prepared and characterized by X-ray powder diffraction, differential scanning calorimetry (DSC), MS-FAB spectrometry, 1H-NMR spectroscopy, water and phase solubility. The solubility studies have revealed different complexation equilibria for optically pure DHP enantiomers, and corresponding racemic mixtures in water solutions. By means of 1H-NMR chemical shift measurements, the inclusion of aromatic fragments of racemic and enantiomerically pure DHP molecules within the cavities of different CDs was elucidated. Considerable stereoselectivity in complexation interactions was observed. The results indicate the potential use of cyclodextrins as chiral selectors for enantiomeric resolution of 1,4-DHP calcium antagonists. © 1993 Wiley-Liss, Inc. 相似文献
20.
Edmund T. Hamann 《Anthropology & education quarterly》2003,34(4):438-449
The large corpus of scholarship of cultural anthropologist Laura Nader is relevant to the contemporary practice of the anthropology of education. In particular, her work is relevant to contemporary debates about methodology and what constitutes "scientifically based" education research; to the prospect and need for more crossfertilization within the discipline of anthropology; and for the proud assertion of anthropology's distinctive suitability for understanding and responding to many contemporary educational challenges, including how to have anthropologically derived insights more favorably compete in the "marketplace of ideas" against less empirically grounded claims and strategies. 相似文献