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21.
Understanding the composition of urban wildlife communities is crucial to promote biodiversity, ecosystem function and links between nature and people. Using crowdsourced data from over five million eBird checklists, we examined the influence of urban characteristics on avian richness and function at 8443 sites within and across 137 global cities. Under half of the species from regional pools were recorded in cities, and we found a significant phylogenetic signal for urban tolerance. Site-level avian richness was positively influenced by the extent of open forest, cultivation and wetlands and avian functional diversity by wetlands. Functional diversity co-declined with richness, but groups including granivores and aquatic birds occurred even at species-poor sites. Cities in arid areas held a higher percentage of regional species richness. Our results indicate commonalities in the influence of habitat on richness and function, as well as lower niche availability, and phylogenetic diversity across the world's cities.  相似文献   
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Curcumin has a plethora of biological properties, making this compound potentially effective in the treatment of several diseases, including cancer. However, curcumin clinical use is compromised by its poor pharmacokinetics, being crucial to find novel analogs with better pharmacokinetic and pharmacological properties. Here, we aimed to evaluate the stability, bioavailability and pharmacokinetic profiles of monocarbonyl analogs of curcumin. A small library of monocarbonyl analogs of curcumin 1a–q was synthesized. Lipophilicity and stability in physiological conditions were both assessed by HPLC-UV, while two different methods assessed the electrophilic character of each compound monitored by NMR and by UV-spectroscopy. The potential therapeutic effect of the analogs 1a–q was evaluated in human colon carcinoma cells and toxicity in immortalized hepatocytes. Our results showed that the curcumin analog 1e is a promising agent against colorectal cancer, with improved stability and efficacy/safety profile.  相似文献   
24.
OBJECTIVES--To determine the short and long term outcome of patients admitted to hospital after initially successful resuscitation from cardiac arrest out of hospital. DESIGN--Review of ambulance and hospital records. Follow up of mortality by "flagging" with the registrar general. Cox proportional hazards analysis of predictors of mortality in patients discharged alive from hospital. SETTING--Scottish Ambulance Service and acute hospitals throughout Scotland. SUBJECTS--1476 patients admitted to a hospital ward, of whom 680 (46%) were discharged alive. MAIN OUTCOME MEASURES--Survival to hospital discharge, neurological status at discharge, time to death, and cause of death after discharge. RESULTS--The median duration of hospital stay was 10 days (interquartile range 8-15) in patients discharged alive and 1 (1-4) day in those dying in hospital. Neurological status at discharge in survivors was normal or mildly impaired in 605 (89%), moderately impaired in 58 (8.5%), and severely impaired in 13 (2%); one patient was comatose. Direct discharge to home occurred in 622 (91%) cases. The 680 discharged survivors were followed up for a median of 25 (range 0-68) months. There were 176 deaths, of which 81 were sudden cardiac deaths, 55 were non-sudden cardiac deaths, and 40 were due to other causes. The product limit estimate of 4 year survival after discharge was 68%. The independent predictors of mortality on follow up were increased age, treatment for heart failure, and cardiac arrest not due to definite myocardial infarction. CONCLUSION--About 40% of initial survivors of resuscitation out of hospital are discharged home without major neurological disability. Patients at high risk of subsequent cardiac death can be identified and may benefit from further cardiological evaluation.  相似文献   
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Rats received continuous administration of cis-flupenthixol (0.8-1.2 mg/kg/day) or trans-flupenthixol (0.9-1.2 mg/kg/day) in drinking water for 14 months. The administration of cis-flupenthixol, but not trans-flupenthixol, caused apparent cerebral dopamine receptor supersensitivity. Thus, animals receiving cis-flupenthixol, but not trans-flupenthixol, showed enhanced apo-morphine-induced stereotyped behaviour. Dopamine concentration in striatum was not altered by drug treatment but striatal HVA and DOPAC concentrations were reduced in animals receiving cis-flupenthixol, but not trans-flupenthixol. No consistent change in Bmax of KD for specific striatal 3H-spiperone binding was observed after 14 months drug intake. However, in cis-flupenthixol treated animals a 40% increase in Bmax was observed following 2 weeks drug withdrawal. Continuous cis-flupenthixol intake increased striatal acetylcholine concentrations; trans-flupenthixol was without effect. This suggests the apparent increase in cerebral dopamine receptor supersensitivity caused by continuous long-term cis-flupenthixol administration is of functional importance in the intact animal.  相似文献   
27.
Physical mapping of herpes simplex virus-induced polypeptides.   总被引:86,自引:73,他引:13       下载免费PDF全文
Analysis of the polypeptides induced by 29 herpes simplex virus type 1/type 2 intertypic recombinants and correlation of the data with the crossover points in the recombinant DNAs have enabled the map positions of many polypeptides to be deduced. These include 25 polypeptides which label with [35S]methionine, 11 which label with [32P]orthophosphate, and 4 which label with [14C]glucosamine. Together with the data of Preston et al. (J. Virol., in press) on the mapping of five immediate-early polypeptides, the results show that representatives of four groups of proteins--immediate-early, late, phosphorylated, and glycosylated--map in both long and short regions. The functional organization of the herpes simplex virus genome does not therefore restrict any of these four groups to either the long or the short region.  相似文献   
28.
Rats treated continually and chronically with trifluoperazine (ca 3 mg/kg/day) for six months initially developed mild catalepsy and an inhibition of spontaneous locomotor activity; both effects disappeared by three months. An initial increase in dopamine turnover (as measured by levels of homovanillic acid and dihydroxyphenylacetic acid) also disappeared by three months. Apomorphine-induced stereotypy was completely inhibited in drug-treated animals at two weeks, but progressively returned to normal after three months of drug intake. An exaggerated response to apomorphine developed in animals after six months of drug administration. Inhibition of striatal dopamine-stimulated adenylate cyclase found during the first month of drug intake was reversed at three months, a trend exaggerated after continuous drug administration for six months. Specific striatal 3H-spiperone binding affinity decreased acutely, but was increased after six months drug intake; no change in number of receptor sites occurred.These changes suggest that at least striatal dopamine receptors may become “supersensitive” during chronic neuroleptic treatment.  相似文献   
29.
Mitogen-activated protein kinase (p42mapk) becomes transiently activated after treatment of serum-starved murine Swiss 3T3 cells or EL4 thymocytes with a diversity of mitogens. Similarly, a meiosis-activated protein kinase (p44mpk) becomes stimulated during maturation of sea star oocytes induced by 1-methyladenine. Both p42mapk and p44mpk have been identified as protein-serine/threonine kinases that are activated as a consequence of their phosphorylation. Because homologous protein kinases may play essential roles in both mitogenesis and oogenesis, we have compared in detail the biochemical properties of these two kinases. We find that these kinases are highly related based on their in vitro substrate specificities, sensitivity to inhibitors, and immunological cross-reactivity. However, they differ in apparent molecular weight and can be separated chromatographically, indicating that the two enzymes are distinct. Furthermore, in the course of this investigation, we have identified a 44-kDa protein kinase in mitogen-stimulated Swiss mouse 3T3 cells and EL4 thymocytes that co-purifies with p44mpk and thus appears to be a closer homolog of the sea star enzyme. Analysis of these protein kinases clarifies the relationships between a set of tyrosine-phosphorylated 41-45-kDa proteins present in mitogen-stimulated cells (Martinez, R., Nakamura., K. D., and Weber, M. J. (1982) Mol. Cell. Biol. 2, 653-655; Cooper, J. A., and Hunter, T. (1984) Mol. Cell. Biol. 4, 30-37), two myelin basic protein kinases identified in epidermal growth factor-treated Swiss mouse 3T3 cells (Ahn, N. G., Weiel, J. E., Chan, C. P., and Krebs, E. G. (1990) J. Biol. Chem. 265, 11487-11494), and p42mapk. Our work points to the existence of a group of related serine/threonine protein kinases, regulated by tyrosine phosphorylation and functioning at different stages of the cell cycle.  相似文献   
30.
The Duchenne muscular dystrophy locus is remarkable in that it shows a high mutation rate and the majority of mutations found are deletions. These deletions are generated as meiotic as well as mitotic events and occur preferentially in the central region of the gene. Nothing is known so far about the mechanisms involved. This paper reports the first sequencing of deletion junctions in the dystrophin gene. The data from a study of two patients with deletions in the central region of dystrophin show the breakpoints to lie in regions of introns in which stretches of dA-dT are seen. The relationship between these observations and possible mechanisms for the mutations is discussed.  相似文献   
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