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91.
Christopher C Perry Monique Weatherly Tiffany Beale Alexandrine Randriamahefa 《Journal of the science of food and agriculture》2009,89(6):958-964
BACKGROUND: In this study the effects of ampicillin and aqueous garlic extract on Escherichia coli (ATCC 9637) and Staphylococcus aureus (ATCC 25923) were compared. Atomic force microscopy (AFM) was used to study the possible mechanisms of membrane disruption. RESULTS: Ampicillin disrupted the cell membrane of E. coli, inducing pores and cell leakage. Aqueous garlic extract also induced leakage from the cell membrane in E. coli, but no pores were observed. The trend in Young's modulus for E. coli was Enative ≈ Eage > Eamp. In contrast, S. aureus incubated with low ampicillin (≤50µg mL?1) and garlic (≤50 mg mL?1) concentrations showed no significant changes in surface morphology compared with the untreated bacterium. The trend in Young's modulus for S. aureus was Enative ≈ Eage ≈ Eamp. CONCLUSION: The trend Enative ≈ Eage for E. coli and S. aureus supports the hypothesis that the compounds in garlic show intracellular activity. This proof‐of‐concept study of the aqueous crude isolate of garlic points to the feasibility of further AFM investigations to compare the antimicrobial properties of various pure thiosulfinate isolates found in garlic. Copyright © 2009 Society of Chemical Industry 相似文献
92.
The velocities of granular solids in a mass-flow bunker have been derived from a series of uninterrupted passages of a miniature radio pill transmitter which followed closely the solids flow lines. The increased accuracy inherent in this technique, as compared with more usual “stopped flow” observations, has confirmed the presence of a dynamic arch in the upper region of the hopper, corresponding to the surface of initial acceleration of the solids. However, below the dynamic arch the solids velocity does not remain constant until the free-fall arch near the outlet from the hopper is attained, as assumed earlier; the velocity increases towards the outlet, and at any height in the hopper decreases towards the wall.A velocity discontinuity observed near the axis of the hopper suggests that the assumption that the stress distribution converges to a radial stress distribution near the outlet can only be valid for less than 3% of the solids in the hopper. 相似文献
93.
Titus S. Seilheimer Patrick L. Zimmerman Kirk M. Stueve Charles H. Perry 《Journal of Great Lakes research》2013
The Great Lakes watersheds have an important influence on the water quality of the nearshore environment, therefore, watershed characteristics can be used to predict what will be observed in the streams. We used novel landscape information describing the forest cover change, along with forest census data and established land cover data to predict total phosphorus and turbidity in Great Lakes streams. In Lake Superior, we modeled increased phosphorus as a function of the increase in the proportion of persisting forest, forest disturbed during 2000–2009, and agricultural land, and we modeled increased turbidity as a function of the increase in the proportion of persisting forest, forest disturbed during 2000–2009, agricultural land, and urban land. In Lake Michigan, we modeled increased phosphorus as a function of ecoregion, decrease in the proportion of forest disturbed during 1984–1999 and watershed storage, and increase in the proportion of urban land, and we modeled increased turbidity as a function of ecoregion, increase in the proportion of forest disturbed during 2000–2009, and decrease in the proportion softwood forest. We used these relationships to identify priority areas for restoration in the Lake Superior basin in the southwestern watersheds, and in west central and southwest watersheds of the Lake Michigan basin. We then used the models to estimate water quality in watersheds without observed instream data to prioritize those areas for management. Prioritizing watersheds will aid effective management of the Great Lakes watershed and result in efficient use of restoration funds, which will lead to improved nearshore water quality. 相似文献
94.
Oncocytic lesions of the caruncle and other ocular adnexa 总被引:2,自引:0,他引:2
This is a clinicopathologic study of 18 oncocytic lesions involving the ocular adnexa. These lesions most commonly occur in elderly patients (median age 73), and there is a striking predilection for women. The broad spectrum of lesions included oncocytic adenomatous hyperplasia, oncocytomas, and oncocytic carcinoma. Ten lesions, all of which were oncocytomas, involved the caruncle, four the conjunctiva, and one the mucocutaneous junction of the eyelid. Two tumors involved the lacrimal sac and one the lacrimal gland. A review of the literature disclosed only 17 previously reported oncocytic lesions of the ocular adnexa. A small yellowish-tan or reddish caruncular mass, especially in an elderly woman, should alert the ophthalmologist to consider the possibility of oncocytoma in his differential diagnosis. 相似文献
95.
Physical training is associated with a reduction of intrinsic sinoatrial activity; the present study examined the role of the parasympathetic nervous system in this reduction. Six groups of rats were studied for 10 weeks: inactive control; treadmill exercised; parasympathetic receptor blockade with atropine; exercise plus atropine; parasympathetic receptor stimulation with carbachol; and exercise plus carbachol. In vivo ISF (cardiac frequency 20 min after injection of propranolol and atropine) was measured at 3-week intervals. At the end of 10 weeks the right atrium was excised, in vitro measurements were made of ISF, and chronotropic dose-response curves to acetylcholine and norepinephrine were established. In vivo, ISF was reduced with time, the greatest reduction being found in the exercise plus atropine group; the treadmill-exercised and the atropine-treated groups also had a greater reduction than the control group. In vitro, no differences were observed in acetylcholine responses. The maximum norepinephrine chronotropic response was reduced in the treadmill-exercised and the exercise plus atropine groups. The maximum norepinephrine-induced frequency correlated with the in vitro ISF (r = 0.75). Thus, ISF was reduced with training, but this effect was independent of parasympathetic activity. The properties of the sinoatrial node which set ISF also influenced the maximum norepinephrine response. 相似文献
96.
In the experiment reported in this paper, 22 of 35 neurons in the gustatory NTS were found to respond to odorant as well as taste stimuli. This odorant response was apparently mediated by the ethmoid nerve and at least one other odorant-responsive system, possibly other nasal trigeminal afferents. These gustatory neurons responded to odorants, as they did to taste stimuli, in a manner consistent with an encoding of stimulus quality information. Thus at least some of the neurons of the gustatory NTS carry information concerning several of the senses involved in ingestion. 相似文献
97.
98.
Sinus histiocytosis is a newly recognized benign disease affecting mainly children and young adults and usually having a protracted clinical course that is relatively unaffected by therapy. This paper describes four additional patients who had orbital involvement initially and reviews the salient clinical and histopathologic features of this entity. The outstanding clinical feature is cervical lymphadenopathy. Associated findings include low-grade fever, anemia, leukocytosis, and elevated IgG levels. A small percentage of patients develop proptosis with palpable orbital tumors. Such patients may not have appreciable lymphadenopathy. Progressive proptosis may lead to exposure keratitis, corneal ulceration, endophthalmitis, and loss of the eye. Histopathologically, the lymph nodes and orbital mass show a proliferation of large histiocytes intermixed with a variable proportion of lymphocytes and plasma cells. Lymphocytes and occasionally other cells derived from the hematopoietic system are commonly seen within the cytoplasm of the histiocytes. 相似文献
99.
Interactions of lectins with glycolipids in liposomes 总被引:2,自引:0,他引:2
100.
FH Shen DJ Baylink RL Nielsen DJ Sherrard JL Ivey MR Haussler 《Canadian Metallurgical Quarterly》1977,90(6):955-962