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931.
932.
In a four year study on a wheat-green gram (or cowpea) — pearl millet intensive cropping system a total production of 9–10 tonnes of wheat equivalents per year removed 29–30kg P ha–1. If only 26 kg P ha–1 was used then total grain production as well as P uptake, was highest when all the P was applied to wheat. Only when amounts larger than 26 kg P ha–1 were applied was it justified to apply P to pearl millet and green gram (or cowpea). Productivity of the cropping system increased up to 58.5 kg P ha–1 and at this level two thirds of P was applied to wheat, while pearl millet and green gram or cowpea received the remaining one-third. A positive P balance in soil was observed only when 26 k P ha–1 yr–1 or more was applied.Pressure of growing population and per capita diminution or arable land has focussed attention on multiple cropping systems in many Asian countries [1, 2]. In North-Western India the cropping system changed from a single rainy (July–October) or winter (November–April) crop a year prior to the 1960's to two-crops-a-year (both a rainy season and winter crop) in the 1970.s and then in the late 1970's a third summer (May–June) crop was also included. Wheat — green gram (or cowpea) — pearl millet is such a three-crops-a-year multiple cropping system.Phosphate is the costliest major plant nutrient in India and farmers following multiple cropping systems are keen to know the way the phosphate should be apportioned to different crops in a cropping system particularly when small amounts of P are applied. Such information can come only from long-term P fertilization experiments [3, 4]. The objective of the present experiment on a wheat-green gram (or cowpea) — pearl millet multiple cropping system was to study the direct and residual effects of P applied to one crop on the other crops grown in succession and to find the best possible way in which a limited amount of P could be apportioned between the different crops in the rotation. An attempt has also been made to work out the P balance in soil.  相似文献   
933.
The authors describe the use of evoked electromyographic responses recorded in the anal sphincter induced by stimulation of the bladder wall and urethra in evaluating lesions of the conus medullaris and cauda equina in 110 patients. This reflex response took effect by way of the pelvic nerves and cauda equina to the sacral cord where the pudendal nerve nucleus was activated, resulting in a contraction of the external anal sphincter. Various lesions along this pathway have been shown to produce either increased latencies and depressed responses or complete loss of response depending on the extent of the lesion. The correlation of results of this technique with clinical, myelographic, and operative findings indicate it to be a useful clinical tool.  相似文献   
934.
郑景翔  常学军 《石油仪器》2000,14(3):32-36,39
文件管理器是SN388应用程序中的一个子菜单。它提供了一些直观处理文件的方法。在SN388操作与维护中经常应用到,特别是在补钉软件的安装过程中。文章简单的介绍了常规的窗口使用方法,重点介绍了文件查看、编辑、查找、修改等方法,最后列举了一个利用文件管理器排除一个实际故障的方法。  相似文献   
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937.
Posttraumatic headache can be a very difficult syndrome to manage, especially if chronic. As with most other types of headache, medications are the primary treatment modality, although there is very limited evidence-based data to support any given approach. A number of physical interventions also are available to be used in conjunction with medication, particularly for headaches with a musculoskeletal component. This article will review the general principles of pharmacological treatment for headache and the physical approach to treatment of headaches and head and facial pain. The major categories of medications commonly used for treatment of many varieties of headache will be discussed. In addition, the problems encountered in diagnosing and treating chronic daily headache and analgesic rebound headache are addressed. The approach to treatment of such syndromes as myofascial pain, cervico-zygapophyseal joint pain, neuritic pain, and craniocervical somatic pain are outlined.  相似文献   
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939.
Relationships between recall of low and high imagery paired-associate (P-A) words and hypnotic susceptibility, and the influence of hypnosis on recall as moderated by hypnotic level were examined. Subjects were assessed on 2 hypnotic susceptibility scales [Harvard Group Scale of Hypnotic Susceptibility; Stanford Hypnotic Susceptibility Scale, Form C (SHSS:C)]. Forty-one low (0-4 SHSS:C) and 41 highly (9-12 SHSS:C) hypnotizable college students were assigned to 1 of 4 experimental groups: waking-hypnosis, hypnosis-waking, waking-waking, or hypnosis-hypnosis. Recall was significantly better for high than low imagery words. In the more sensitive within-subjects design, high hypnotizables recalled more P-A words during hypnosis than waking, and lows did not differ. In the between-subjects design, hypnotic level was not a moderator of performance during hypnosis. Low hypnotizables recalled more words in the within-subjects design. Visualization ability was a poor moderator of imagery-mediated learning. High imagery recall correlated significantly with Marks's (1973) Vividness of Visual Imagery Questionnaire (.25) and Paivio and Harshman's (1983) Individual Differences Questionnaire (IDQ) Verbal scale (.29), but not with the IDQ Imagery scale, the Mental Rotations Test (Vandenberg & Kuse, 1973), or the revised Minnesota Paper Form Board Test (Likert & Quasha, 1941).  相似文献   
940.
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