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141.
Kozhiparambil K. Purushothaman Ayyappath Sarada Ariyamuthu Saraswathy Joseph D. Connolly 《Phytochemistry》1983,22(4):1042-1043
Sempervirenic acid, a new diterpene has been isolated from Solidago sempervirens and its structure determined by spectroscopic methods and chemical conversions to be 3β-acetoxy-labda-7,13-diene-15-oic acid. 相似文献
142.
A power supply has been designed to improve liquid isoelectric focusing by automatically maintaining constant power applied to the column. The main advantages are (a) a reduced exposure time which is particularly important when sensitive proteins are being resolved; (b) a reduction in the loss of resolution due to diffusion or denaturation of the proteins; and (c) a considerable increase in efficiency of the use of the equipment for preparative purposes. 相似文献
143.
Topographical control of cell behaviour. I. Simple step cues 总被引:5,自引:0,他引:5
P Clark P Connolly A S Curtis J A Dow C D Wilkinson 《Development (Cambridge, England)》1987,99(3):439-448
The photolithographic techniques of the microelectronics industry have allowed us to fabricate patterned plastic substrata to investigate contact guidance of animal tissue cells. The reactions of cells to single steps on a substratum were examined using time-lapse videorecording and scanning electron microscopy. BHK cells and chick embryonic neural cell processes exhibited gradual inhibition of crossing steps with a concomitant increase in alignment at steps dependent on increasing step height. Comparison of these cells' reactions, with those of chick heart fibroblasts and rabbit neutrophils, at a 5 micron step revealed that the influence of topography is also dependent on cell type, the neutrophils being relatively unaffected. The presence of an adhesive difference at a series of steps altered BHK cells' reactions such that the frequency of crossing was dependent on the direction of approach to a step. Although our data are consistent with Dunn & Heath's proposal (1976) that the inflexibility of the cytoskeleton of a moving cell's protrusion is the cellular property determining such reactions to topography, we have found that, on encountering a topographical feature, the response of a cell may be predictable on a probabilistic basis, i.e. the topographical feature reduces the probability of a cell making a successful protrusion and contact in a given direction, that even the largest features tested did not act as absolute barriers to cell locomotion since a small proportion of a population of cells were able to overcome them, and that other guidance cues could significantly alter a cell's response. Even in situations where it is not the primary cue in directing cell locomotion, topographical control may be an important factor during morphogenesis since it must, at the very least, influence the efficiency of other cues. 相似文献
144.
145.
OBJECTIVE--To compare the efficacy of home based care with standard hospital care in treating serious mental illness. DESIGN--Randomised controlled trial. SETTING--South Southwark, London. PATIENTS--189 patients aged 18-64 living in catchment area. 92 were randomised to home based care (daily living programme) and 97 to standard hospital care. At three months'' follow up 68 home care and 60 hospital patients were evaluated. MAIN OUTCOME MEASURES--Use of hospital beds, psychiatric diagnosis, social functioning, patients'' and relatives'' satisfaction, and activity of daily living programme staff. RESULTS--Home care reduced hospital stay by 80% (median stay six days in home care group, 53 days in hospital group) and did not increase the number of admissions compared with hospital care. On clinical and social outcome there was a non-significant trend in favour of home care, but both groups showed big improvements. On the global adjustment scale home care patients improved by 26.8 points and the hospital group by 21.6 points (difference 5.2; 95% confidence interval -1.5 to 12). Other rating scales showed similar trends. Home care patients required a wide range of support in areas such as housing, finance, and work. Only three patients dropped out from the programme. CONCLUSIONS--Home based care may offer some slight advantages over hospital based care for patients with serious mental illness and their relatives. The care is intensive, but the low drop out rate suggests appreciation. Changes to traditional training for mental health workers are required. 相似文献
146.
147.
Tracking elusive cargo: Illuminating spatio‐temporal Type 3 effector protein dynamics using reporters 下载免费PDF全文
Type 3 secretion systems form an integral part of the arsenal of many pathogenic bacteria. These injection machines, together with their cargo of subversive effector proteins, are capable of manipulating the cellular environment of the host in order to ensure persistence of the pathogen. In order to fully appreciate the functions of Type 3 effectors, it is necessary to gain spatio‐temporal knowledge of each effector during the process of infection. A number of genetic modifications have been exploited in order to reveal effector protein secretion, translocation and subsequent activity, and localisation within host cells. In this review, we will discuss the many available approaches for tracking effector protein dynamics and discuss the challenges faced to improve the current technologies and gain a clearer picture of effector protein function. 相似文献
148.
Nine adult leafy seadragons Phycodurus eques were tracked using ultrasonic telemetry for between 2-10 days around West Island, Australia. All fish except one moved within well-defined home ranges of up to 5 ha (using minimum convex polygon method). Short bursts of movement (at average velocities of 2-17 m h−1 ) punctuated long periods (up to 68 h) without movement. The exceptional fish moved almost in a straight line away from its tagging location near the end of the tracking period, at a maximum velocity of 146 m h−1 . There was no constant diel pattern in movements; some fish moved more at night, others during the day. The time leafy seadragons spent over particular habitats compared to the area of those habitats available at the study site was greater for Posidonia seagrass, about as expected for kelp-covered reefs and bare sand patches, and less than expected for Amphibolis seagrass and boulders covered with brown algae. In searching for tagging effects, a comparison of movement immediately after tagging showed no difference with subsequent movements for most fish. The lack of tagging effect may be because the transmitter can be attached to the bony appendages away from the body of the fish. There was no sign of damage to fish upon removal of transmitters after tracking. 相似文献
149.
Triploidy (69,XXY) in a liveborn infant 总被引:1,自引:0,他引:1
150.
Four isomeric sesquiterpenoid lactones have been isolated from the liverwort Frullania tamarisci They have been identified as the simple eudesmanolides (I–III) and costunolide (IV). 相似文献