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排序方式: 共有768条查询结果,搜索用时 24 毫秒
71.
72.
Aníbal E Carbajo Carolina Vera Paula LM González 《International journal of health geographics》2009,8(1):44-10
Background
Oligoryzomys longicaudatus (colilargo) is the rodent responsible for hantavirus pulmonary syndrome (HPS) in Argentine Patagonia. In past decades (1967–1998), trends of precipitation reduction and surface air temperature increase have been observed in western Patagonia. We explore how the potential distribution of the hantavirus reservoir would change under different climate change scenarios based on the observed trends. 相似文献73.
高效液相色谱法测定消痰咳片的含量 总被引:2,自引:0,他引:2
目的:采用反相色谱法同时测定消痰咳片中两种主要成分甲氧苄啶和磺胺体的含量。方法:以乙腈:0.1%H3PO4(15:85)为流动相,检测波长254nm,HPLC法测定含量。结果:试验表明,甲氧苄啶和磺胺林在0.8-8ug范围内呈良好的线性关系,回归方程分别为Y=-1127.1+110.2x(r=0.9994),Y=-1852.3 256.2x(r=0.9996),相对标准偏差分别为2.1%和0.8%。结论:该方法简便、准确、可靠。 相似文献
74.
The EuroQoL EQ-5D and MOS SF-36 are two generic quality of life measures that differ significantly in their design (the former being an index and the latter a profile). Both have been extensively used in evaluating interventions in acute disease. This study tested their comparative performance in a survey of patients with relapsing-remitting multiple sclerosis (MS).
METHODS: 309 patients with diagnosed relapsing-remitting MS were identified through the records of 5 specialist centers in North West England. Patients were contacted by telephone by a specialist MS nurse and asked to complete a set of questionnaires distributed by mail. The questionnaire booklet reproduced the English version of SF-36, together with the EQ-5D and a self completion form of the Barthel. Minimal additional background information was obtained from all respondents; 4 weeks following their completion of the initial booklet, a second identical booklet was sent to the first 200 initial respondents. Patients in this re-test sub-group were asked whether their health status had improved, deteriorated, or remained unchanged over the intervening period.
RESULTS: Of the 200 patients in the test/re-test subgroup, 144 (72%) replied on both occasions. Paired t-tests for the PCS, MCS, and general health perception scores on the SF-36 failed to generate comprehensive evidence of reliability. The weighted index form of the EQ-5D and the visual analogue scale self-ratings provided superior evidence of reliability. Standardized response means for both measures confirmed this general pattern.
CONCLUSION: EQ-5D performs satisfactorily as a generic measure of health-related quality of life in patients with MS. 相似文献
METHODS: 309 patients with diagnosed relapsing-remitting MS were identified through the records of 5 specialist centers in North West England. Patients were contacted by telephone by a specialist MS nurse and asked to complete a set of questionnaires distributed by mail. The questionnaire booklet reproduced the English version of SF-36, together with the EQ-5D and a self completion form of the Barthel. Minimal additional background information was obtained from all respondents; 4 weeks following their completion of the initial booklet, a second identical booklet was sent to the first 200 initial respondents. Patients in this re-test sub-group were asked whether their health status had improved, deteriorated, or remained unchanged over the intervening period.
RESULTS: Of the 200 patients in the test/re-test subgroup, 144 (72%) replied on both occasions. Paired t-tests for the PCS, MCS, and general health perception scores on the SF-36 failed to generate comprehensive evidence of reliability. The weighted index form of the EQ-5D and the visual analogue scale self-ratings provided superior evidence of reliability. Standardized response means for both measures confirmed this general pattern.
CONCLUSION: EQ-5D performs satisfactorily as a generic measure of health-related quality of life in patients with MS. 相似文献
75.
Stimulus generalization of fear responses: effects of auditory cortex lesions in a computational model and in rats 总被引:3,自引:2,他引:1
Armony JL; Servan-Schreiber D; Romanski LM; Cohen JD; LeDoux JE 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(2):157-165
The conditioning of fear responses to a simple acoustic stimulus (pure
tone) paired with footshock can be mediated by the transmission of auditory
information to the lateral nucleus of the amygdala from either the auditory
thalamus or the auditory cortex. We examined the processing capacity of the
thalamo-amygdala pathway by making lesions of the auditory cortex and
testing the extent to which conditioned fear responses generalized to tones
other than the one paired with footshock. Two studies were performed, one
in an anatomically constrained computational model of the fear conditioning
network and the other in rats. Stimulus generalization was unaffected in
both. These findings support the validity of the model as an approach to
studying the neural basis of conditioned fear learning, and in addition
suggest that the thalamo-amygdala pathway, possibly by the use of
population coding, is capable of performing at least crude stimulus
discriminations.
相似文献
76.
P LoRusso A J Wozniak L Polin D Capps W R Leopold L M Werbel L Biernat M E Dan T H Corbett 《Cancer research》1990,50(16):4900-4905
PD115934 (NSC 366140) is a soluble pyrazoloacridine derivative presently undergoing preclinical toxicology evaluation with the anticipation of Phase I human investigation. The agent displayed both human and murine solid tumor selectivity in vitro in a soft agar disk diffusion assay, relative to its activity against murine L1210 leukemia. In vivo it was highly active against solid tumors colon adenocarcinoma 38 and pancreas ductal carcinoma 03, which was consistent with the cellular cytotoxicity seen in the disk diffusion assay. A log cell kill of greater than 4.0 was demonstrated in vivo against both models. PD115934 was administered by both bolus and infusional therapy. After completion of these trials, it was determined that this compound was a schedule category III agent, i.e., a schedule-independent agent with peak plasma level toxicity. The main toxicity encountered with infusional therapy was myelosuppression. With bolus therapy, central nervous system toxicities were dose limiting. On the basis of our preclinical infusion studies, we recommend a 2-h infusion twice weekly in humans in order to obtain a total dose of 360 mg/m2 over 8 weeks. 相似文献
77.
There is increasing evidence to suggest that abnormalities in apoptosis may
play a part in the pathogenesis of systemic lupus erythematosus (SLE). For
example, there is now considerable evidence that bel-2 expression is
enhanced in a proportion of peripheral T cells, but not in B cells, in SLE
patients and correlates with overall disease activity regardless of the
activity index employed. Further work is required to establish whether
enhanced bel-2 expression by some T cells in SLE patients is related to
their activation or intrinsically enhanced by genetic predisposition.
Mutations in Fas result in a lymphoproliferative syndrome and may play a
role in accelerating autoimmune disease. A report of three children with
mutations in Fas has once again focused attention on this regulator of
apoptosis. The relationships between inducers and inhibitors of apoptosis
may differ in different cell types, and must be elucidated before the
implications of observations made in lymphocytes from SLE patients can be
fully understood.
相似文献
78.
79.
提出了非相关成分参比一倍率导数光谱法用于测定混合组分体系的基本原理和实验方法。本法可用于待测成分和非相关成分导数光谱严重重叠且待测成分含量较低时的不经分离直接测定。试用本法消除了甲氧苄啶(TMP)和磺胺甲嚼唑(SMZ)及附加剂之间的相互干扰,从而测定了部分制剂中的TMP:用“零交法”测定了SMZ,平均回收率分别为:102.5±1.63%(CV)和100.3±0.99%(CV)。 相似文献
80.
K Haug LM Irgens V Baste T Markestad R Skjærven P Schreuder 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(10):1023-1027
To explore the association between smoking and breastfeeding, we obtained data from a retrospective questionnaire-based national survey comprising a random sample (n = 34 799) of all mothers giving birth in Norway 1970-91. Variables studied were postpartum smoking habits for both parents, duration of breastfeeding, infant's year of birth and parental age. The response rate was 70% (n = 24 438). During the study period, the maternal postpartum smoking prevalence decreased from 38% to 26%. The proportion breastfeeding at 6 months increased from 15% to 44% among smokers, and from 30% to 72% among non-smokers. In spite of a considerable increase in breastfeeding both among smokers and non-smokers, the proportion of breastfeeding, non-smoking women at 6 months was twice that of smoking women during the whole period. Furthermore, the duration of breastfeeding was shorter among young mothers and when the fathers were smoking. There was epidemiological evidence that the effect on breastfeeding of smoking might represent both biological and social mechanisms. 相似文献