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Notes that augment an earlier essay on R. S. Williams’ botanical activities and the distribution of his collections from Bolivia and Peru are presented. Twelve species based on Williams’ vascular plant collections are added to a catalog that was previously published. Synonymies of an additional 22 taxa are corrected or updated. Notes also are provided concerning the typification or orthography of two species.  相似文献   
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Isidrogalvia longiflora, a new combination based onAsagraea longiflora, is proposed. It is the first record ofIsidrogalvia from Bolivia.  相似文献   
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In 1843 S. B. Buckley (1809–1884) traveled up the St. Johns River, Florida in search of plants, shells, and possibly other natural history objects. Buckley encountered many difficulties in interior Florida and his trip did not live up to his original expectations. It was unfortunate that the took years to distribute his plant specimens, since few botanists or naturalists had preceded him into that poorly explored region.  相似文献   
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This work studies water permeability properties of human aquaporin 1 (hAQP1) expressed in Xenopus laevis oocyte membranes, applying a technique where cellular content is replaced with a known medium, with the possibility of measuring intracellular pressure. Consequences on water transport—produced by well-known anisotonic gradients and by the intracellular effect of probable aquaporin inhibitors—were tested. In this way, the specific intracellular inhibition of hAQP1 by the diuretic drug furosemide was demonstrated. In addition, experiments imposing anisotonic mannitol gradients with a constant ionic strength showed that the relationship between water flux and the applied mannitol gradient deflects from a perfect osmometer response when the gradient is higher than 150 mosmol kgW−1. These results would indicate that the passage of water molecules through hAQP1 may have a maximum rate. As a whole, this work demonstrates the technical advantage of controlling both intracellular pressure and medium composition in order to study biophysical properties of hAQP1, and contributes information on water channel behavior under osmotic challenges and the discovery of new inhibitors.  相似文献   
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There is a need for safe medications that can effectively support recovery by treating symptoms of protracted abstinence that may precipitate relapse in alcoholics, e.g. craving and disturbances in sleep and mood. This proof-of-concept study reports on the effectiveness of gabapentin 1200 mg for attenuating these symptoms in a non-treatment-seeking sample of cue-reactive, alcohol-dependent individuals. Subjects were 33 paid volunteers with current Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence and a strength of craving rating 1 SD or greater for alcohol than water cues. Subjects were randomly assigned to gabapentin or placebo for 1 week and then participated in a within-subjects trial where each was exposed to standardized sets of pleasant, neutral and unpleasant visual stimuli followed by alcohol or water cues. Gabapentin was associated with significantly greater reductions than placebo on several measures of subjective craving for alcohol as well as for affectively evoked craving. Gabapentin was also associated with significant improvement on several measures of sleep quality. Side effects were minimal, and gabapentin effects were not found to resemble any major classes of abused drugs. Results suggest that gabapentin may be effective for treating the protracted abstinence phase in alcohol dependence and that a randomized clinical trial would be an appropriate next step. The study also suggests the value of cue-reactivity studies as proof-of-concept screens for potential antirelapse drugs.  相似文献   
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The study aimed to explore the suicidal process, suicidal communication and psychosocial situation of young suicide attempters in a rural community in Hanoi, Vietnam. Semi-structured interviews were conducted, in a community setting, with 19 suicide attempters aged 15-24 who had been consecutively hospitalized in an intensive care unit. In 12 of 19 cases, the first pressing, distinct and constant suicidal thoughts appeared less than one day before the suicide attempt in question. However, distress and mild, fleeting suicidal thoughts had been present up to six months before the suicide attempt in 16 cases. Five respondents had a suicide plan one to three days before attempting suicide. Altogether, 13 engaged in some form of suicidal communication before their attempt. This communication was, however, difficult for outsiders to interpret. Twelve of the respondents were victims of regular physical abuse and 16 had suffered psychological violence for at least one year before attempting suicide. Eighteen of the respondents used pesticides or raticides in their suicide attempts. None sought advice or consultation in the community despite long-standing psychosocial problems. The strategy of reducing the availability of suicide means (e.g., pesticides or raticides) in Asian countries should be complemented with a long-term suicide-preventive strategy that targets school dropouts and domestic violence, and promotes coping abilities and communication about psychological and social problems as well as recognition of signs of distress and suicidal communication.  相似文献   
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Observing that the conidia of Stachybotrys chartarum can germinate in the lung of infant rats, it became important to ascertain whether an infection can ensue. Viable conidia of S. chartarum were instilled into the lungs of 4 and 14 day-old rat pups. Germination was observed frequently in the lungs of 4 day-old but rarely in the 14 day-old pups. In the 4 day-old pups, pulmonary inflammation with hemorrhagic exudates was observed and resulted in about 15% mortality rate compared to 0% for the controls instilled with phosphate buffered saline. Acute neutrophilic inflammation and intense interstitial pneumonia with poorly formed granulomas observed three days following exposure were associated with fungal hyphae and conidia. The surviving experimental pups showed significantly slower weight gain for seven days. Dilution plating and quantitative PCR analysis were used to follow total fungal load in the rat pups lung homogenates. In the 4 day-old rat pups viable fungi decreased rapidly and were less than 1% by day seven. Similarly, fungal DNA decreased exponentially and was only 0.03% by fourteen days after exposure. However, 14 day-old rat pups showed neither the lethal effects of exposures to viable conidia of S. chartarum nor the slower weight gain, and the fungal load decreased even more rapidly. We conclude that S. chartarum conidia can initially germinate and form hyphae but even in the immature rat pups do not establish an effective infection, although a very limited persistence cannot be excluded.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   
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