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51.
Using electronic strain gauges, longitudinal peripheral growth strain was measured at 1.6 m height in fifty 22-year-old plantation grown trees of Eucalyptus grandis (Hill) Maiden.

The extent of peripheral growth strain was not found to be related to rate of growth. This result and measurements of internal growth strains in five 32-year-old trees suggested that splitting of wood during conversion would be less likely in trees with faster rates of growth, due to a lower longitudinal strain gradient along a radius from pith to outer xylem.  相似文献   
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Piperazine‐based ‘party pills’ containing 1‐benzylpiperazine (BZP) and 1‐(m‐trifluorophenylmethylphenyl)piperazine (TFMPP) have become increasingly popular in New Zealand and many other countries. The aim of this study was to collect data on the population prevalence and related harm from legal party pill use in New Zealand. A national household sample of 2010 people aged 13–45 years old was collected using a computer‐assisted telephone interviewing (CATI) facility. Twenty per cent of the sample had tried legal party pills and 15% had used them in the previous year. Approximately 40% of males aged 18–24 years old had used legal party pills in the past year. While most users reported fairly minor problems from use, such as insomnia (50% of last year users), some users reported potentially more serious physical problems, such as ‘vomiting’ (12%), ‘inability to urinate’ (10%), ‘chest pains’ (4%) and ‘seizures’ (0.8%). Users also reported a range of psychological problems from use such as visual hallucinations (9%), paranoia (8%) and depression (8%). Two per cent of last year users were classified as dependent on legal party pills using a short dependency scale. The extent of harms and incidences of more serious problems, suggest that stricter regulation of the sale and use of legal party pills in New Zealand may be appropriate.  相似文献   
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We studied the value of an IgG Western blot (WB) with Paragonimus kellicotti (Pk) antigen for diagnosis of North American paragonimiasis. The test was evaluated with sera from patients with Pk and Paragonimus westermani infections, with control sera from patients with other helminth infections, and sera from healthy Americans. All 11 proven Pk infection sera and two samples from suspected cases that were negative by P. westermani WB at the Centers for Disease Control and Prevention (CDC) contained antibodies to antigens at 34 kDa and at 21/23 kDa. Seven of 7 P. westermani sera contained antibodies to the 34 kDa antigen, but only 2 recognized the 21/23 kDa doublet. No control samples were reactive with these antigens. Antibody reactivity declined after praziquantel treatment. Thus, the P. kellicotti WB appears to be superior to P. westermani WB for diagnosing Pk infections, and it may be useful for assessing responses to treatment.  相似文献   
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The newer monoamine oxidase inhibitors have clinical actions in hypertension and angina pectoris similar to those of iproniazid but appear to produce less frequent side effects. Some of the side effects suggest that in addition to amine oxidase inhibition, they may also have a ganglionic blocking action.

The amine oxidase inhibitors are effective and useful in the clinical management of refractory cases of angina pectoris even though they may not alter the electrocardiogram significantly. Since the relief of chest pain also is accompanied frequently by a sense of well-being, cautioning the patient against over-exertion is advisable. Some of the amine oxidase inhibitors are also worthy of a trial in resistant cases of hypertension. However, they should be employed cautiously in these selected cases since their long term effects, even in moderate dosage, on liver and cardiac function are not known.  相似文献   

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Alternative regimes for the treatment of Schistosoma haematobium infection were compared in two trials. Praziquantel at a dose of 40 mg kg-1 appeared to cure 63% of a random sample of heavily infected subjects; significantly more than the 18% cured by three fortnightly doses of metrifonate at 10 mg kg-1. However, praziquantel led to a greater incidence of mild, transient side-effects. A single dose of metrifonate was found to be an inadequate treatment in the same group of subjects as it left 53% with an egg count of at least 100 ova/10 ml. A combination of 10 mg kg-1 of metrifonate and 25 mg kg-1 of niridazole had a similar effect to that of a single dose of metrifonate alone and it had more side-effects. Reduced doses of praziquantel had less effect on egg counts than the standard regime, but the difference was not significant in the case of 20 mg kg-1. Although a combination of metrifonate and praziquantel, each at 10 mg kg-1, had a greater effect than either constituent alone, the difference was not significant. Factors affecting the choice of drug for use in mass treatment of urinary schistosomiasis in The Gambia are discussed. The present findings suggest that the standard regime of praziquantel should be used or, if this is not possible, a three-dose metrifonate regime.  相似文献   
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