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941.
942.
This scientific literature review focuses on the relation between nursing work and low-back problems. Its aim was to estimate the risk of physical, psychosocial, and work organizational exposure factors that may lead to low-back problems. In addition this paper reviews and evaluates reported ergonomic intervention, with the object of decreasing the prevalence and incidence of low-back problems among nurses. A considerable number of studies of nursing staff has shown the connection between lifts and transfers of patients on one hand and low-back problems on the other. Factors in nursing work that may be significant in this connection are staff density and work satisfaction. In this review the single individual factor that was indisputably related to low-back problems was "history of back problems". Prevention programs do not show unequivocally positive results. There is a great need to carry out prospective studies with preventive programs. 相似文献
943.
944.
B Cacciatore E Halmesm?ki R Kaaja K Teramo O Ylikorkala 《Canadian Metallurgical Quarterly》1998,179(1):140-145
BACKGROUND: Uncertainty exists about the extent and consequences of a return to alcohol consumption after liver transplantation for alcoholic liver disease (ALD). AIMS: To determine the prevalence and consequences of alcohol consumption in patients transplanted for ALD. METHODS: A retrospective case controlled study of all patients transplanted for ALD at the Queen Elizabeth Hospital, Birmingham, between 1987 and 1996. RESULTS: Seventy patients with ALD were transplanted, of which 59 survived more than three months; 56 were interviewed. Twenty eight had consumed some alcohol after transplantation; for the nine "heavy drinkers" (HD), the median time to resumption of alcohol intake was six months and for the 19 "moderate drinkers" (MD) it was eight months. There was no significant difference in episodes of acute rejection or compliance with medication between those who were abstinent, MD, or HD. Histological evidence of liver injury was common in ALD patients who had returned to drink. Mild fatty change was found in 1/11 biopsy specimens from abstinent patients but moderate to severe fatty change and ballooned hepatocytes were seen in 3/5 MD and 2/5 HD specimens. Two HD patients had early fibrosis. One HD patient had died of alcohol related complications. CONCLUSIONS: Moderate to heavy alcohol consumption occurs in patients transplanted for ALD. Patient recall of abstinence advice is unreliable, and patients return to alcohol mainly within the first year after liver transplantation. Return to alcohol consumption after liver transplantation is associated with rapid development of histological liver injury including fibrosis. 相似文献
945.
It has been suggested that some occupational groups have a high risk of contracting chronic inflammatory bowel diseases. A cohort, comprising 2,273,872 male and female Danes aged 20-59 on 1 January 1981, and a cohort similarly defined as of 1 January 1986 were followed up for hospitalizations due to chronic inflammatory bowel disease until 31. December 1990. From 1981 to 1990, 6296 first time admissions occurred. Among 15 groups previously found to be at high or low risk only female office staff and health personnel had statistically significantly increased standardized hospitalization ratios. Occupations with non-daytime work did not have an increased risk. Occupations with predominantly sedentary work had a standardized hospitalization ratio of 125 (95% confidence interval 116.9-133.1) compared to occupations without sedentary work. Self-employed had low hospitalization rates, while 'other salaried staff' and "not economically active" had high rates. 相似文献
946.
AK Lepp?niemi 《Canadian Metallurgical Quarterly》1998,22(12):1197-1201
The most prevalent menace since the end of the cold war is the occurrence of civil wars and local and regional conflicts. The term "low intensity conflict" describes the new threat environment and covers a multitude of phenomena, such as civil wars, guerrilla warfare, terrorism and counterinsurgency operations occurring between routine, peaceful inter- or intrastate competition, and a sustained conventional conflict. There is a great challenge to alert the physicians in general, and the surgical community of the world in particular, to the new threat environment and the medical challenges involved in treating casualties of low intensity conflicts. Specifically, a new international body of surgeons might be required to coordinate the recruitment, training, and creditation for surgeons with special expertise in the management of victims of such conflicts and to facilitate research and general knowledge of the medical challenges of modern conflicts. 相似文献
947.
E Parellada AM Catafau M Bernardo F Lome?a S Catarineu E González-Monclús 《Canadian Metallurgical Quarterly》1998,44(8):787-790
BACKGROUND: Functional neuroimaging findings of "hypofrontality" in schizophrenic patients is still controversial, due to the heterogeneity of methods and patient samples. This study tries to prevent some of these concerns by studying neuroleptic-naive (NN) and neuroleptic-free (NF) young female patients both in resting conditions and during a frontal cognitive activation task. METHODS: Regional cerebral blood flow (rCBF) was studied at rest and during the Wisconsin Card Sorting Test (WCST) in 25 young acute unmedicated schizophrenic female patients (14 NN and 11 NF) and 15 female controls, using single photon emission computed tomography. RESULTS: The schizophrenic and control groups did not differ in rCBF during the baseline condition, but the schizophrenic group failed to activate the frontal lobe during the WCST condition. In addition, the left anterior temporal rCBF at rest correlated with the Scale for the Assessment of Positive Symptoms total score. CONCLUSIONS: The results suggest that hypofrontality in young acute unmedicated schizophrenic patients is a result of an inability to activate frontal regions during cognition, rather than a baseline decrease in frontal activity. Furthermore, positive symptoms seem to be associated with left temporal cortex activity. 相似文献
948.
Infrequent "deviant' auditory stimuli embedded in a homogeneous sequence of "standard' sounds evoke a neuromagnetic mismatch field (MMF), which is assumed to reflect automatic change detection in the brain. We investigated whether MMFs would reveal hemispheric differences in cortical auditory processing. Seven healthy adults were studied with a whole-scalp neuromagnetometer. The sound sequence, delivered to one ear at time, contained three infrequent deviants (differing from standards in duration, frequency, or interstimulus interval) intermixed with standard tones. MMFs peaked 9-34 msec earlier in the right than in the left hemisphere, irrespective of the stimulated ear. Whereas deviants activated only one MMF source in the left hemisphere, two temporally overlapping but spatially separate sources, one in the temporal lobe and another in the inferior parietal cortex, were necessary to explain the right-hemisphere MMFs. We suggest that the bilateral MMF components originating in the supratemporal cortex are feature specific whereas the right-hemisphere parietal component reflects more global auditory change detection. The results imply hemispheric differences in sound processing and suggest stronger involvement of the right than the left hemisphere in change detection. 相似文献
949.
IuV Plastinina LI Privalova SIu Ter?shin BA Katsnel'son NS Kislitsina 《Canadian Metallurgical Quarterly》1996,(7):16-20
Experiments on white rats proved that the silicotic pulmonary changes slowed with the tails periodically immersed into iodine solution. Those pulmonary changes were due to inhalation of quartzite dust and especially due to intratracheal administration of standardized quartz dust DQ12. Influenced by inhalation of dust containing quartz, the rats demonstrated characteristic alterations in cytologic features of bronchial and alveolar lavage water. The "iodine baths" also declined those alterations, that may prove higher resistance of pulmonary macrophages to cytotoxic effects of quartz. This hypothesis finds a support in experiments with culture of rat peritoneal macrophages. If incubated in a medium with low iodine concentrations and subsequently washed off, the macrophages demonstrate lower incidence of cytotoxic effects due to the next incubation with particles of DQ12. The macrophage's higher resistance against cytotoxic agents is believed to result directly in antisilicotic effect of iodine, so "iodine baths" could be recommended for pathogenetic therapy and medical prophylaxis of silicosis. 相似文献
950.
JA Ortu?o-Cortés L Quintana-Tomás A García-García 《Canadian Metallurgical Quarterly》1996,19(2):47-51
1.5% Capsaicin (Cap) or Vehicle was respectively used to treat the right or left sciatic nerve in 20 Sprague-Dawley rats. On the seventh day, the 20 rats were at random divided into electroacupuncture (EA) group and non-EA group, the spinal cord corresponding to the afferent segments of sciatic nerve was taken out for observing the changes of acetylcholinesterase (AChE) activity and [3H]-quinuelidinylbenzylate (QNB) binding sites in the spinal dorsal horn (SDH). The results were as follows: (1) EA "Huantiao" could enhance AChE activity in the SDH and decrease [3H]-QNB binding sites; (2) Cap treating sciatice nerve could weaken AChE activity in the SDH and merease [3H]-QNB binding sites; (3) Cap treatment could inhibit or partially inhibit the actions of EA as above. The results indicated that ACh participated in the primary afferent of acupuncture information and might exist in Cap-sensitive neurons. 相似文献