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41.
Z Katsarava A Dzagnidze M Kukava E Mirvelashvili M Djibuti M Janelidze R Jensen LJ Stovner & TJ Steiner 《Cephalalgia : an international journal of headache》2009,29(9):949-952
We present a study of the general-population prevalence of cluster headache in the Republic of Georgia and discuss the advantages and challenges of different methodological approaches. In a community-based survey, specially trained medical residents visited 500 adjacent households in the capital city, Tbilisi, and 300 households in the eastern rural area of Kakheti. They interviewed all ( n = 1145) biologically unrelated adult occupants using a previously validated questionnaire. The household responses rates were 92% in Tbilisi and 100% in Kakheti. The survey identified 32 persons with possible cluster headache, who were then personally interviewed by one of two headache-experienced neurologists. Cluster headache was confirmed in one subject. The prevalence of cluster headache was therefore estimated to be 87/100 000 (95% confidence interval < 258/100 000). We used a conservative approach, which has an obvious advantage of high-quality data collection, but is very demanding of manpower and time. 相似文献
42.
Three recent publications have reported the development of erythema multiforme and Stevens-Johnson syndrome in patients receiving cranial irradiation and sodium phenytoin. Some authors have recommended that patients receiving whole brain radiation therapy and who have had seizures should not be prescribed phenytoin but an alternative anticonvulsant. This article reviews the current literature pertaining to the development of this potentially lethal complication in patients receiving whole brain radiation and phenytoin, with reference to the single recorded case of Stevens-Johnson syndrome in a patient receiving cranial irradiation and phenytoin in Auckland, New Zealand. While the clinical picture in the 16 patients reported in the literature and the current case report differed from the classical form of erythema multiforme, a similar pattern of presentation and outcome appeared in all patients reviewed, suggesting that the combination of phenytoin, cranial irradiation and the gradual reduction of concomitant steroids seem to lead to the development of erythema multiforme and/or Stevens-Johnson syndrome. The data presented, although sparse, suggest that phenytoin should not be prescribed in patients receiving cranial irradiation. 相似文献
43.
1临床资料2002-01/2004-02收治临床症状典型且无并发症毛细支气管炎患儿116例,发病年龄3-24(平均8.4)mo,男61例,女55例,按就诊时间顺序分为氨溴索雾化吸入组(观察组)、氨溴索静脉点滴组(对照Ⅰ组)和常规治疗组(对照Ⅱ组),分别为38,39,39例.常规治疗组给予头孢噻肟钠50mg/kg,2/d及穿琥宁80-120mg/d分别静脉滴注及对症治疗(如吸氧、镇静、退热等处理);观察组在常规治疗的基础上加用氨溴索4mg加生理盐水10mL超声雾化吸入10~15min,2/d; 相似文献
44.
J John LJ Björklund NW Svenningsen B Jonson 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(9):903-909
Failure of neonatal patient triggered ventilation may reflect a delay in delivery of flow relative to the inspiratory effort of the infant. Transmission of diaphragmatic contraction to the sensor site (patient delay) and further transmission to and within the sensing device (device delay) both contribute to the delay in triggering. Patient and device delays were studied for different sensing systems in 36 infants, 24 of whom were intubated. Device delay was long (<40 ms) with a conventional apnoea monitor compared with sensors placed at the airway opening (2 ms), the inspiratory (12 ms) and expiratory (3 ms) pressure transducers of the ventilator, the Graseby capsule (8 ms), strain gauges (3 ms) and oesophageal pressure (6 ms). In near normal infants, the sum of patient and device delays for the latter sensors was less than 20 ms and a minor component of the total delay. However, in severe lung disease the total delay may be more than 100ms even for airway sensors. 相似文献
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48.
Acquired pendular nystagmus: its characteristics, localising value and pathophysiology 总被引:5,自引:4,他引:1
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Investigations were made of 16 patients with acquired pendular nystagmus and a further 32 cases reported in the literature were reviewed. Amongst our own patients two thirds had multiple sclerosis, almost one third a cerebrovascular accident or angioma and two had optic atrophy with squint. The nystagmus took forms which could be monocular or binocular, conjugate or disconjugate and could involve movements about single or multiple axes. Spectral analysis was used to characterise the amplitude and frequency of the movements and to estimate the degree of relationship (coherence) between movements of the two eyes or between movements of one eye about several axes. The oscillations ranged in frequency from 2·5 Hz to 6 Hz, with typical amplitudes between 3° and 5°. In a given patient all oscillations, regardless of plane, were highly synchronised. Somatic tremors of the upper limb, face and palate associated with the nystagmus were often at similar frequencies to the eye movement. The other ocular signs common to all our patients were the presence of squint with failure of convergence. Most patients also had skew deviation or internuclear ophthalmoplegia or both. The major oculomotor systems, that is, saccades, pursuit, optokinetic and vestibulo-ocular reflexes could be intact. It is inferred that the mechanism responsible for the pendular nystagmus lies at a level which is close to the oculomotor nuclei so that it can have monocular effects but is not part of the primary motor pathways. It is possible that this mechanism normally subserves maintenance of conjugate movement and posture of the eyes. The periodicity of the nystagmus is likely to arise from instability in a certain type(s) of neurone, for the associated somatic tremors have similar characteristics and yet involve very different neuronal muscular circuitry. Prognosis for cessation of the nystagmus is poor. In five patients with multiple sclerosis it was suppressed by intravenous hyoscine with, however, unacceptable subsequent side effects. 相似文献
49.
G B Ruvkun F M Ausubel 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(1):191-195
Cloned nitrogen fixation (nif) genes from Klebsiella pneumoniae hybridize to DNA from 19 out of 19 widely divergent nitrogen-fixing bacterial strains but do not hybridize to DNA from 10 different non-nitrogen-fixing species. K. pneumoniae nif DNA fragments that hybridize to DNA from other species contain part of the three structural genes that code for nitrogenase polypeptides. We have utilized this homology to clone an EcoRI restriction endonuclease fragment from Rhizobium meliloti that hybridizes to the K. pneumoniae nif structural genes. Some of the species whose DNA hybridizes with K. pneumoniae nif DNA have been postulated to have diverged from K. pneumoniae 3 x 10(9) years ago. Nitrogenase genes are the only known example of such highly conserved prokaryotic translated genes. Nitrogenase genes are either extraordinarily conserved in evolution or have been exchanged between different nitrogen-fixing species relatively recently in evolutionary time. 相似文献
50.
Understanding diet and energy balance as risk factors for breast, colon,
and other cancers requires information on the contribution of each factor
and of interactions among factors to cancer risk. Rodent models for breast
cancer provide extensive data on effects of dietary fat and calories,
energy balance, body weight gain, and physical activity on tumor
development. Analyses of the combined data from many studies have shown
clearly that quality and quantity of dietary fat and energy balance
contribute independently to increased mammary gland tumorigenesis. These
findings were seen in female rats fed diets high in fat (35-40% of
calories) compared to rats fed control diets, with approximately 10% of
calories as fat (Fay and Freedman, 1997, Breast Cancer Res. Treat. 46,
215-223). The methods used permit comparison of experimental and
epidemiological data, and they may be useful in extrapolating between
species and developing public health recommendations. In addition to the
contributions of lifetime-diet composition, intake, energy balance, and
physical activity to cancer risk, there are questions about the timing and
duration of alterations in these factors and about the "dose-response"
characteristics of cancer risk to the factors. Endocrine mechanisms may be
significant in mammary gland tumor risk, but experimental and
epidemiological data indicate that cancers at other sites, such as colon
and liver, also are influenced by the factors listed. Other diet and
lifestyle factors that influence energy, or specifically fat, metabolism
may also affect risk for cancers that are promoted by increased intake of
fat and calories. Studies of separate and interactive effects of dietary
fat, black tea, weight gain, and mammary gland tumorigenesis (Rogers, et
al, 1998, Carcinogenesis 19, 1269-1273) have been analyzed. Using
adjustment of carcinogenesis endpoints for body weight, tumor burden, and
latency, they were found to be related to weight gain within treatment
groups in 2 of 3 experiments.
相似文献