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1.
Begum S  Hassan SI  Siddiqui BS 《Planta medica》2002,68(12):1149-1152
Two new triterpenoids, guajavolide (2 alpha,3 beta,6 beta,23-tetrahydroxyurs-12-en-28,20 beta-olide; 1) and guavenoic acid (2 alpha,3 beta,6 beta,23-tetrahydroxyurs-12,20(30)-dien-28-oic acid; 2) along with one known triterpene oleanolic acid (3) were isolated from the fresh leaves of Psidium guajava. Their structure elucidation and stereochemistry were determined by spectroscopic experiments, including 2D-NMR techniques.  相似文献   
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Purpose of Review

Rectal cancer is predominantly a disease of older adults but current guidelines do not incorporate the associated specific challenges leading to wide variation in the delivery of cancer care to this subset of population. Here, we will review the current data available regarding the management of rectal cancer in older adults.

Recent Findings

The greatest challenge arises in the management of stage II/III disease as it involves tri-modality treatment that can be harder to tolerate by frail older patients. Response to neoadjuvant treatment is being used as a new marker to tailor further therapy and possibly avoid surgery. Oxaliplatin can be omitted from the adjuvant treatment without compromising outcomes.

Summary

Physicians should perform geriatric assessment utilizing many validated tools available to help predict treatment tolerability and outcomes in older adults that can help personalize subsequent management. Most older adults can undergo standard therapy for stages I, II, or III rectal cancer with curative intent. Increasing evidence suggests that patients with a clinical complete response to neoadjuvant treatment may be observed closely with the possibility of avoiding surgery. Studies are evaluating alternate systemic treatments for advanced metastatic disease with the hope of maintaining quality of life without compromising cancer outcomes.
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Pleomorphic adenoma, or chondroid syringoma (CS), is a rare, benign, skin appendageal tumour. Because of the unremarkable clinical presentation of this rare tumour, the diagnosis is made on microscopic examination. The usual presentation is of an asymptomatic, slowly-growing mass, typically located in the head and neck region. We present a case of a CS located over the forehead of a 32-year-old man. In the evaluation of a middle-aged male patient with a small cutaneous nodule in the head and neck region, chondroid syringoma should also be considered in the differential diagnosis. For such a lesion, excisional biopsy, without destroying the aesthetic and functional structures, is the preferred diagnostic, as well as therapeutic approach.  相似文献   
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The current study was aimed at investigating the potential antidepressant activity of Areca catechu nut ethanol extract and its various fractions using behavioral (acute and sub‐chronic forced swim tests) and biochemical (monoamines and their metabolite levels using high performance liquid chromatography) tests. The areca nut ethanol extract and its aqueous fraction exhibited antidepressant activity in both acute and sub‐chronic forced swim tests (IC50 ~ 50 and 20 mg/kg, respectively), which was further confirmed by unaltered locomotor (horizontal and vertical) activities of rats in the activity cage. Phytochemical analysis revealed that saponins of areca nut may be the active component in its antidepressant action. The rats treated sub‐chronically with areca nut extract displayed toxic effects, whereas its active aqueous fraction was non‐toxic, indicating the presence of different constituents for antidepressant and toxic effects. In the hippocampus of rats, the areca nut extract (50 mg/kg) and aqueous fraction (20 mg/kg) caused a significant elevation of serotonin (around 35%) and noradrenaline (around 30%) compared with the control (261 ± 25 and 512 ± 29 ng/g, respectively). In conclusion, the areca nut possesses potential antidepressant effect via the elevation of serotonin and noradrenaline. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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Family environment plays a very important role in early child development and the availability of stimulating material in the early years of a child's life is crucial for optimising development. The Home Observation for Measurement of the Environment (HOME) inventory is one of the most widely used measures to assess the quality and quantity of support and stimulation provided for children at home. This cross-sectional study aims to measure the existing situation of home environment with respect to child development using the HOME scale in two communities of Pakistan: TandoJam (Sindh) and Mastung (Baluchistan). From December 2009 until May 2010, all mothers with children from birth to age three were recruited for the study. Data on the home environment were collected from a cohort of 1,097 children using the Infant and Toddler HOME (IT-HOME) scale, further distributed over six subscales. Frequency distributions of all responses and mean and standard deviation for all subscales were calculated. The mean ± standard deviation age of study children was 16.6 ± 12.1 months. Overall, the mean score on the HOME scale was 31.7 ± 7.2 and 29.7 ± 6.9 in TandoJam and Mastung respectively. On a subscale level, about one-half of the families in TandoJam and three-quarters in Mastung scored in the lowest quarter category on the Learning Material subscale, whereas 41% of families in Mastung and 18% of families in TandoJam were in the lowest quarter on the Organization subscale. On the remaining three scales (Responsivity, Involvement and Variety) at least 50% of families scored in the upper quarter category. In conclusion, considerable evidence is available showing that poor home environment retards intellectual growth. The HOME inventory identified up to 23% of young children in the lowest quarter category who are potentially at risk of developmental delays. There is a need to develop culturally acceptable, evidence-based parenting interventions to improve the home environment.  相似文献   
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This study describes the spasmolytic, antidiarrhoeal, antisecretory, bronchodilatory and urinary bladder relaxant properties of Hyoscyamus niger to rationalize some of its medicinal uses. The crude extract of H. niger seeds (Hn.Cr) caused a complete concentration-dependent relaxation of spontaneous contractions of rabbit jejunum, similar to that caused by verapamil, whereas atropine produced partial inhibition. Hn.Cr inhibited contractions induced by carbachol (1 microM) and K(+) (80 mM) in a pattern similar to that of dicyclomine, but different from verapamil and atropine. Hn.Cr shifted the Ca(2+) concentration-response curves to the right, similar to that caused by verapamil and dicyclomine, suggesting a Ca(2+) channel-blocking mechanism in addition to an anticholinergic effect. In the guinea-pig ileum, Hn.Cr produced a rightward parallel shift of the acetylcholine curves, followed by a non-parallel shift with suppression of the maximum response at a higher concentration, similar to that caused by dicyclomine, but different from that of verapamil and atropine. Hn.Cr exhibited antidiarrhoeal and antisecretory effects against castor oil-induced diarrhoea and intestinal fluid accumulation in mice. In guinea-pig trachea and rabbit urinary bladder tissues, Hn.Cr caused relaxation of carbachol (1 microM) and K(+) (80 mM) induced contractions at around 10 and 25 times lower concentrations than in gut, respectively, and shifted carbachol curves to the right. Only the organic fractions of the extract had a Ca(2+) antagonist effect, whereas both organic and aqueous fractions had anticholinergic effect. A constituent, beta-sitosterol exhibited Ca(2+) channel-blocking action. These results suggest that the antispasmodic effect of H. niger is mediated through a combination of anticholinergic and Ca(2+) antagonist mechanisms. The relaxant effects of Hn.Cr occur at much lower concentrations in the trachea and bladder. This study offers explanations for the medicinal use of H. niger in treating gastrointestinal and respiratory disorders and bladder hyperactivity.  相似文献   
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Studies on the chemical constituents of the stems of Morinda citrifolia, Linn. have led to the isolation of two new compounds, morindicone (9-hydroxy-2-methoxy-4-methyl-3,10-anthracenedione, 1) and morinthone (4-methoxy-3-heptadecylxanthone, 2), as well as two known constituents, 1-hydroxy-2-methylanthraquinone (3) and 2-hydroxymethylanthraquinone (4). Their structures were elucidated by spectral analysis including 2D NMR techniques.  相似文献   
10.
The functional-neuroanatomic relationship that describes the involvement of the parietal cortex in visual search was investigated using repetitive transcranial magnetic stimulation (rTMS; 10 Hz, 500 ms in duration). Twelve adult participants performed feature-based visual search for a unique letter-without eye movements-under conditions that involved manipulations of search efficiency (efficient versus inefficient) and target-selection demands (set-size: 4 versus 10). rTMS was applied over the right posterior parietal cortex at the onset of the search array for all factorial conditions (0-500 ms); stimulation was additionally administered at 500 ms post-array onset (500-1000 ms) during inefficient search (set-size 10). Stimulation over the primary sensorimotor cortex served as a within-subjects control condition, and eye movements were monitored continuously. Significant increases in reaction time were restricted to parietal stimulation during inefficient search (set-size 10), with interference observed when rTMS was administered at the onset of the search array and at 500 ms post-array onset. The early effect was confined to target-present trials and the late effect was confined to target-absent trials, which may indicate temporally dissociable parietal involvement in target detection and response-based selection and/or search termination, respectively. Error rates did not vary significantly as a function of any of the independent variables. Taken together, these results are consistent with evidence from functional magnetic resonance studies indicating that inefficient feature-based visual search requires an intact parietal cortex, and also indicate that the parietal cortex is involved in inefficient search later than has been previously reported.  相似文献   
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