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131.
132.
133.
Marlowe CK Sinha U Gunn AC Scarborough RM 《Bioorganic & medicinal chemistry letters》2000,10(1):13-16
A series of arginine aldehyde inhibitors was designed as transition state (TS) analogues based on the known factor Xa specific substrate Cbz-D-Arg-Gly-Arg-pNA. BnSO2-(D)Arg-Gly-Arg-H (20) was found to be the most potent and selective inhibitor of factor Xa and prothrombinase activity in this series. 相似文献
134.
135.
Sinha A 《Medical anthropology quarterly》2000,14(3):291-309
This article considers the role of telemedicine in the production of biomedical health care using three specific theoretical constructs as lenses through which to examine this phenomenon: (1) Foucault's medical "gaze"; (2) the political economy of health; and (3) deterritorialization and multisite ethnography. This examination focuses first on the changing corporate structure of health care and changing political attitudes toward telemedicine. Second, it documents the current use of telemedicine in prisons, the military, and in cross-cultural settings. Third, it discusses responses to telemedicine of individual physicians, health care staff, and patients, finding that these responses are broadly conditioned by an individual's mode of articulation with biomedical institutions and that they are mediated by personal experience. 相似文献
136.
Factors determining the midday depression of photosynthesis in trees under monsoon climate 总被引:9,自引:0,他引:9
Field studies of gas exchange of Populus deltoides, Prosopis juliflora and Acacia auriculiformis showed large diurnal changes in net photosynthesis (A) and stomatal conductance (gs) during autumn. P. deltoides and P. juliflora undergo pronounced midday depression in A and gs while A. auriculiformis showed a one-peak response. Several factors indicative of photosynthetic performance were found to be reversibly affected
during afternoon decline. These include (i) decrease in initial slope of the CO2 response curve (carboxylation efficiency), (ii) substantial increase in CO2 compensation point and (iii) decrease in overall quantum yield of photosystem II. The phenomenon can be duplicated in potted
plants by simulating a typical daily pattern of PPFD and VPD. It is found that high VPD induces significant decline in A and
gs at moderate temperature and saturating PPFD (800 μmol m–2 s–1) whereas these parameters are only marginally affected at high PPFD and low VPD. Fluorescence data show that the tree species
under study have a high capacity for safe dissipation of excessive excitation energy. The activation of photorespiration,
as evident from an increase in CO2 compensation point, maintains constant internal CO2 concentration (Ci) which may aid in minimizing photoinhibition during stomatal closure at midday. In case of P. deltoides and P. juliflora the stomata seem to be quite sensitive to the changes in humidity whereas this does not appear to be essential in case of
A. auriculiformis because of its phyllode structure that endows it with mechanisms for conserving water without undergoing large-scale stomatal
changes.
Received: 16 October 1997 / Accepted: 5 March 1998 相似文献
137.
A Sinha 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1998,353(1368):619-631
The pressures of developing and maintaining intricate social relationships may have led to the evolution of enhanced cognitive abilities in many nonhuman primates. Knowledge of the dominance ranks and social relationships of other individuals, in particular, is important in evaluating one''s position in the rank hierarchy and affiliative networks. Triadic interactions offer an excellent opportunity to examine whether decisions are taken by individuals on the basis of such knowledge. Allogrooming supplants among wild female bonnet macaques (macaca radiata) usually involved the subordinate female of a grooming dyad retreating at the approach of a female dominant to both members of the dyad. In a few exceptional cases, however, the dominant member of the dyad retreated; simple non-cognitive hypotheses involving dyadic rank differences and agonistic relationships failed to explain this phenomenon. Instead, retreat by the dominant individual was positively correlated with the social attractiveness of her subordinate companion (as measured by the duration of grooming received by the latter from other females in the troop). This suggests that not only does an individual evaluate relationships among other females, but does so on the basis of the amount of grooming received by them. Similarly, the frequency of approaches received by any female was correlated with her social attractiveness when she was the dominant member of the dyad, but not when she was the subordinate. This indicated that approaching females might be aware of the relative dominance ranks of the two allogrooming individuals. In logistic regression analyses, the probability of any individual retreating was found to be influenced more by her knowledge of her rank difference with both the other interactants, rather than by their absolute ranks. Moreover, information about social attractiveness appeared to be used in terms of correlated dominance ranks. The nature of knowledge acquired by bonnet macaque females may thus be egotistical in that other individuals are evaluated relative to oneself, integrative in that information about all other interactants is used simultaneously, and hierarchical in the ability to preferentially use certain categories of knowledge for the storage of related information from other domains. 相似文献
138.
Uttara Mendiratta Ajith Kumar Charudutt Mishra Anindya Sinha 《American journal of primatology》2009,71(11):939-947
The newly described Arunachal macaque Macaca munzala occurs largely in sub‐tropical to temperate environments at elevations of c. 1,800–3,000 m in Arunachal Pradesh, northeastern India. We studied its over‐wintering strategy by comparing the diet, ranging, and behavior of a troop of 24 individuals during winter and spring (December 2005 to May 2006) through instantaneous scan sampling (3,002 records, 448 scans, 112 hr of observation). We also monitored the phenology of food plants. The macaques spent more time (41–66%) feeding in the winter than in spring (33–51%), whereas time spent moving and resting was greater in spring. The diet composed largely of plants, with animal matter being eaten rarely. The number of plant species in the diet increased from 18 to 25 whereas food types rose from 18 to 36 from winter to spring, respectively. Although only two species formed 75% of the winter diet, seven species comprised this proportion in spring. Availability of fruits and young leaves increased in spring; the troop moved more and utilized a larger part of its range during this time. Seasonal changes in behavior could be explained by the scarcity of food and the costs of thermoregulation in winter. Our study suggests that the Arunachal macaque inhabits a highly seasonal environment and has an over‐wintering strategy that includes subsisting on a high‐fiber diet by increasing the time spent feeding, and minimizing energy expenditure by reducing the time spent moving. Am. J. Primatol. 71:939–947, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
139.
Blunted suppression of acyl‐ghrelin in response to fructose ingestion in obese adolescents: The role of insulin resistance 下载免费PDF全文
140.
Sigamani Ashokkumar Arunai Nambiraj Sujit Nath Sinha Girigesh Yadav Kothanda Raman Manindra Bhushan Rajesh Thiyagarajan 《Reports of Practical Oncology and Radiotherapy》2015,20(3):170-180