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991.
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
992.
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
993.
H. Böcük B. A. Albiss İ Ercan H. Özkan N. Gasanly 《Journal of Low Temperature Physics》1996,105(3-4):975-980
Voltage-current characteristics of YBCO superconductor was studied under magnetic field up to 0.4 T at different temperatures below Tc. The critical temperature decreases and the transition width broadens under magnetic field. V-I data below Tc were fitted to a power law expression V I(T,B) in which (T,B) is found to decrease with increase of magnetic field and temperature, gradually approaching unity as T approaches Tc, being independent of magnetic field. Similarly, (T,B) approaches unity as magnetic field increases being independent of temperature. 相似文献
994.
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
995.
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
996.
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
997.
OBJECTIVE: To compare the reported meal patterns between obese and normal weight men. DESIGN: A dietary survey, by means of 12 repeated telephone-administered 24-hour dietary recalls, was conducted in obese and normal weight men. The study period was three months with all seven days of the week included. The contribution of intake types to the reported daily energy intake (EI) was studied as well as the circadian distribution of EI and the reported number of intakes. SUBJECTS: 86 obese men (BMI 37.7 +/- 4.4 kg/m2, mean +/- SD) from the waiting list of the outpatient clinic completed the study altogether with 61 normal weight men (BMI 23.0 +/- 1.9 kg/m2), randomly selected from the Stockholm County Census Bureau. All men were 20-60 years old. RESULTS: Results were analyzed for Group A = all men who completed the study and for Group B = the men who exceeded the CUT-OFF 1 limit for energy intake (reasonably true report as defined by Goldberg). The obvious under-reporters amounted to 73% of the obese and to 28% of the normal weight men. The meal patterns were similar for the obese and the normal weight men. The greatest contributors to EI in both groups were cooked meals, sandwich meals, snacks and breakfast-like meals. The circadian eating pattern was mainly the same in both obese and normal weight men. The reported number of intakes was 5.3 (median) per day in all obese men vs 5.6 in all the controls (P = 0.02), and in Group B 5.3 s 5.9 (P = 0.16) intakes. No specific "obese eating style' could be detected in this study. 相似文献
998.
I Ilveskoski UM Saarinen M Perkki? TT Salmi M Lanning A M?kipernaa R Sankila H Pihko 《Canadian Metallurgical Quarterly》1996,13(1):69-80
We evaluated the outcome of 68 children with malignant brain tumors treated with the "8 in 1" chemotherapy protocol in Finland from 1986 to 1993, comparing 5-year survival rates with those for a historical control group (from 1975 to 1985). For all malignant brain tumors, overall survival was 43% (vs 28% in the control group; P <0.05), and progression-free survival (PFS) was 43% (vs 23%; P <0.05). For medulloblastoma and primitive neuroectodermal tumor, survival was 63% (vs 35%; P <0.05), and the corresponding PFS was 59% (vs 35%; P = 0.15). For high-grade glioma, both the survival rate and the PFS were 27% (vs 17%; P = NS). Thus the outcome was significantly better for our "8 in 1" -treated patients than for the historical controls, especially among the children with primitive neuroectodermal tumor and medulloblastoma. In contrast, those with high-grade gliomas and brain stem tumors seem to have received little benefit; different, more effective treatments are needed for these patients. 相似文献
999.
During a six-month period 2,221 haemocultures obtained from patients hospitalized in the Faculty Hospital Olomouc were examined. In all 304 isolated bacteria the sensitivity was assessed by the standard dilution micromethod and moreover all positive haemocultures were examined the "direct" disc method. Agreement between the results of the two methods was proved in 84% of pairs of tests and within a range from 67 to 100%, depending on the type of antimicrobial preparation. Based on these findings it may be stated that assessment of the sensitivity by the "direct" method agrees significantly with assessment of the sensitivity according to minimal inhibitory concentrations (MIC). In patients with septicaemia this procedure makes it possible to change empirical antibiotherapy by 24 hours sooner to aimed therapy. 相似文献
1000.
Several questions about the degree to which cultural schedules exist for the timing of life transitions, as well as the nature of these schedules, remain unexplored. In this article, we examine age timetables for central family transitions. Do individuals perceive age deadlines for these transitions, and by what ages do they think that men or women should have experienced them? How much consensus exists about these deadlines? Why are they considered important, and what consequences are perceived for men or women who miss them? A key theoretical question with which we are concerned is whether contemporary thinking about these deadlines can be considered "normative." A random sample of 319 adults from the Chicago metropolitan area were interviewed about eleven separate life-course transitions, six of which were from the family sphere. By and large, the majority of respondents perceived deadlines for most of the family transitions discussed. While the deadlines cited were quite variable in range, they were also concentrated within a narrow band of ages. The dimensions underlying individuals' thinking about deadlines were centered primarily on the development of self and personality, or were linked to concerns about the sequencing of roles and experiences over lifetime. However, late timing was generally thought to be acceptable, accompanied by little social tension, and without consequences for the individual's life or the lives of other persons to whom one is intimately connected. While a rough, "normal biography" of family life existed in the minds of our respondents, the deadlines attached to that biography were flexible guidelines for the course of family life, not rigid, normative principles. These findings are discussed in light of recent debates about life-course theory and research. 相似文献