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排序方式: 共有798条查询结果,搜索用时 15 毫秒
791.
792.
Mucosal iron retention and plasma iron absorption in the duodenum and jejunum of dogs 总被引:2,自引:0,他引:2
The electroretinograms (ERGs) from 14 patients with proliferative diabetic retinopathy were recorded before and after peripheral retinal ablation by photocoagulation. It was expected that the ERG would be reduced in amplitude in proportion to the area of retina destroyed by the treatment. The ablation treatment, carried out in a standard manner in each patient, resulted in a decrease of ERG amplitude that varied from 10 to 95% among the patients, and caused an increase in ERG latency and implicit time in several patients. This suggests a wide variability in the area of retina affected by the treatment, and the possibility of an effect of the procedure on adjacent untreated retina in some diabetic patients. 相似文献
793.
K Prabhakaran EB Harris B Randhawa RC Hastings 《Canadian Metallurgical Quarterly》1995,81(328):177-185
beta-Lactamase has been reported from only a few mycobacteria. It is widely assumed that Mycobacterium avium strains do not contain the enzyme, but earlier assays were done using insensitive methods. Thus the beta-lactamase activity in cell-free extracts of ten selected strains of mycobacteria, including four strains of M. avium, was determined using a highly sensitive spectrophotometric method. The results showed that all the mycobacteria tested possess the enzyme, which explains their resistance to beta-lactam antibiotics. However, some of the bacteria differed from others in the action of the inhibitors, clavulanate, sulbactam and tazobactam against their beta-lactamases. Growth of the mycobacteria was suppressed by novel combinations of the beta-lactam/beta-lactamase-inhibitors, and by a new beta-lactamase-stable cephalosporin, Cefepime (aminothiazolyl methoxyimino cephalosporin). The results presented, as well as reports of previous studies in vivo, suggest that the intracellular growth of the bacilli or the high partition coefficient of a beta-lactamase inhibitor such as sulbactam does not impede the antimycobacterial action of these compounds. 相似文献
794.
CH Martin CA Mayeda CA Davis CL Ericsson JD Knafels DR Mathog SE Celniker EB Lewis MJ Palazzolo 《Canadian Metallurgical Quarterly》1995,92(18):8398-8402
The bithorax complex (BX-C) of Drosophila, one of two complexes that act as master regulators of the body plan of the fly, is included within a sequence of 338,234 bp (SEQ89E). This paper presents the strategy used in sequencing SEQ89E and an analysis of its open reading frames. The BX-C sequence (BXCALL) contains 314,895 bp obtained by deletion of putative genes that are located at each end of SEQ89E and appear to be functionally unrelated to the BX-C. Only 1.4% of BXCALL codes for the three homeodomain-containing proteins of the complex. Principal findings include a putative ABD-A protein (ABD-AII) larger than a previously known ABD-A protein and a putative glucose transporter-like gene (1521 bp) located at or near the bithoraxoid (bxd), infra-abdominal-2 (iab-2) boundary on the opposite strand relative to that of the homeobox-containing genes. 相似文献
795.
796.
797.
J McCauley DE Kern K Kolodner LR Derogatis EB Bass 《Canadian Metallurgical Quarterly》1998,13(10):687-691
OBJECTIVE: To determine if women who experience low-severity violence differ in numbers of physical symptoms, psychological distress, or substance abuse from women who have never been abused and from women who experience high-severity violence. DESIGN: Cross-sectional, self-administered, anonymous survey. SETTING: Four community-based, primary care, internal medicine practices. PATIENTS: Survey respondents were 1,931 women aged 18 years or older. SURVEY DESIGN: Survey included questions on violence; a checklist of 22 physical symptoms; the Symptom Checklist-22 (SCL-22) to measure depression, anxiety, somatization, and self-esteem; CAGE questions for alcohol use; and questions about past medical history. Low-severity violence patients had been "pushed or grabbed" or had someone "threaten to hurt them or someone they love" in the year prior to presentation. High-severity violence patients had been hit, slapped, kicked, burned, choked, or threatened or hurt with a weapon. MAIN RESULTS: Of the 1,931 women, 47 met criteria for current low-severity violence without prior abuse, and 79 met criteria for current high-severity violence without prior abuse, and 1,257 had never experienced violence. The remaining patients reported either childhood violence or past adult abuse. When adjusted for socioeconomic characteristics, the number of physical symptoms increased with increasing severity of violence (4.3 for no violence, 5.3 for low-severity violence, 6.4 for high-severity violence, p < .0001). Psychological distress also increased with increasing severity of violence (mean total SCL22 scores 32.6 for no violence, 35.7 for low-severity violence, 39.5 for high-severity violence, p < .0001). Women with any current violence were more likely to have a history of substance abuse (prevalence ratio [PR] 1.8 for low-severity, 1.9 for high-severity violence) and to have a substance-abusing partner (PR 2.4 for both violence groups). CONCLUSIONS: In this study, even low-severity violence was associated with physical and psychological health problems in women. The data suggest a dose-response relation between the severity of violence and the degree of physical and psychological distress. 相似文献
798.
The rapid development of suppurative reaction in response to a copper-containing intraocular foreign body disposes the eye to a poor prognosis. An intraocular brass foreign body case involving cornea, iris, lens, vitreous and retina was satisfactorily managed by early foreign body removal and corneal transplantation followed by scleral buckling for retinal detachment. Early intervention is advocated as alternative management with expectation of improvement in the prognosis for recovery of useful visual function. 相似文献