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21.
The present experiment explored the utility of finger pulse volume (FPV) as a measure of anxiety. Subjects were exposed to either a threatening or nonthreatening situation, and indices of physiological arousal (pulse rate (PR) and FPV) and self-report of anxiety (Affect Adjective Checklist (AACL)) were collected. Results indicated that FPV was responsive to changes in experimentally induced anxiety and significantly correlated with PR and AACL, although the strength of these relationships was not substantial. Relevance for psychophysiological theory and the clinical observation of anxiety is discussed.  相似文献   
22.
The emigratory behavior and locomotor activity of yellow-eyed (y/y), wildtype (+/+), and heterozygous (+/y) house flies was examined at 8 fc (86 lx) and 1600 fc (17,223 lx) light intenstities. At 8 fc, emigration rate and activity of the y/y flies was similar to that of the +/+ and +/y flies. However, at 1600 fc, the y/y flies emigrated at twice the rate and showed an activity of about one-third that of the other genotypes. The behavior of the +/+ and +/y flies remained similar regardless of the experimental design or light intensity. The excessive neural stimulation by high-intensity light resulting from reduced shielding pigments led to behavioral modifications in the visual and tactile responses of the y/y flies.This research was supported in part by grants from the CUNY Faculty Research Award Program (No. 1103) and NIH Biomedical Research Support Grant 5-S05-R-07064.  相似文献   
23.
Chromosome investigations were carried out in 7 patients with Fanconi's anemia, type Estren-Dameshek. The frequency and types of chromosome instability found in cultured lymphocytes were in accord with those detected in individuals with classical Fanconi's anemia. The break-point distribution indicates a significant excess of breaks in chromosomes No. 1, 2, and 7 and a deficit in No. 18 and X and Y chromosomes. There was a clear clustering of breaks at certain locations in chromosomes No. 1, 2, 3, 7, 9, and 14. The location of the breaks with respect to the bands demonstrated an almost exclusive involvement of the lighter bands, regardless of the banding method used. These results suggest that most breaks take place in the interbands between the G and R bands. In all patients, chromosome instability was less frequent in direct bone marrow preparations than in lymphocyte cultures. However, cultured bone marrow cells showed a significant increase of chromosome aberrations. On the whole, the chromosome data derived from this series of patients are in agreement with those obtained in individuals with classical Fanconi's anemia and give no support to the idea of cytogenetic heterogeneity between subjects affected by these two forms of childhood aplastic anemia.  相似文献   
24.
Direct visualization of crystal growth in poly(L ‐lactide) thin films was carried out by using a temperature‐controlled atomic force microscopy (AFM). At the initial stage of crystallization, edge‐on lamellar crystals have nucleated and elongated. Subsequently, the edge‐on lamellar crystals showed S‐shaped morphology and changed their orientation from edge‐on manner to flat‐on one. The curvature of edge‐on lamellar crystal has been discussed in terms of inclination and distortion of polymer chains in the crystal. In addition, mechanism on the formation of flat‐on crystal from edge‐on lamellae was proposed as derivative growth on the basis of in situ AFM observation of crystal growth and enzymatic degradation.

  相似文献   

25.
Clinical electromyographic (EMG) biofeedback was an outgrowth of diagnostic electromyography and research on the fine control of motor units. In rehabilitation, EMG biofeedback has gained a firm place in the treatment of upper motor neuron lesions, particularly in retraining muscles and inducing relaxation of spastic muscles of stroke patients. In cerebral palsy and musculoskeletal disturbances, additional feedback transducers (e.g., electrogoniometers, pressure-sensitive and position-sensing devices) are gaining wider use. Spasmodic torticollis has proved to be particularly suitable for behavioral methods of treatment, including EMG feedback.  相似文献   
26.
Summary Cyclophosphamide (CPA) is widely used against leukemic and lymphoproliferative diseases, but in vitro studies on response to this agent so far have been limited to instable derivatives with poor galenic properties. ASTA Z 7557 is a newly synthesized LE" BORDER="0">activated cyclophosphamideLE" BORDER="0"> that circumvents the need for hepatic activation and has good stability. The critical cytotoxic lesions after exposure to bifunctional alkylating agents presumably are DNA interstrand crosslinks (ISC). We have, therefore, examined the formation and apparent removal of ISC after in vitro treatment with ASTA Z 7557 by use of the highly sensitive alkaline elution technique. Survival of murine L1210 cells was determined after 1 hour in vitro exposure with a D 37 value of 5.7 LE" BORDER="0">g/ml (from the initial shoulder part of the survival curve) and a Do value of 1.5 LE" BORDER="0">g/ml (from the exponential part of the curve). Previous labelling of L1210 cells by 125IUdR simplified the alkaline elution procedure but there was some cytotoxicity of the radiochemical itself with a reduction of cloning efficiency from 77% to 61 %. The maximum of ISC was observed at 6 h after initiation of treatment with much of the damage apparently removed at 24 h. The simultaneous presence of DNA single strand breaks (SSB), however, confounds the analysis of DNA damage at 24 h and early cytolysis and unaided death of human lymphocytes often preclude the analysis of macromolecular damage at this time. Human peripheral blood cells isolated from patients with leukemic or lymphoproliferative diseases showed a remarkable heterogeneity with regard to the formation of ISC at 3 h. Thus, analysis of macromolecular damage may become an additional prognostic factor for response to CPA beyond the morphologic classification of these diseases.  相似文献   
27.
The hyperosmolarity response of the ocular standing potential was recorded in unilateral rhegmatogenous retinal detachment (8 eyes) and in the fellow LINE" BORDER="0">healthyLINE" BORDER="0"> eye (8 eyes). The hyperosmolarity response was greatly suppressed (M-4 SD: M and SD indicate respectively the mean and the standard deviation in normal subjects) in all affected eyes (p < 0.005), and slightly abnormal in 2 fellow eyes. The L/D ratio was normal in 2 affected eyes and in all fellow eyes. The hyperosmolarity response in the affected eyes was still greatly suppressed 14 months after successful surgical treatment.  相似文献   
28.
This study broadens contextual environments to include adults’ activity spaces—inside and outside the residential neighborhood—to examine how contextual exposures shape type 2 diabetes risk. We use novel longitudinal data from the Los Angeles Family and Neighborhood Survey, construct time-weighted exposure measures of adults’ social-structural and healthy resource environments, and execute random effects logistic models predicting the probability of being diabetic. Results indicate that residential and activity space exposures are independently associated with adult diabetes, and that residential and activity space healthy resources combine to influence diabetes risk in synergistic ways. Living in more socioeconomically advantaged neighborhoods reduces diabetes risk, particularly when spending time in activity spaces with greater access to recreational facilities. Moreover, healthier activity space environments may compensate for living in neighborhoods devoid of healthy food options to lessen diabetes risk. Adopting an activity space framework can inform multilevel interventions aimed at alleviating type 2 diabetes and other chronic ailments.  相似文献   
29.
李皆  王林  李玉明 《河北医学》2001,7(7):590-593
目的:为研究左旋精氨酸、牛磺酸、卡托普利三药合用对自发性高血压大鼠的血压、血脂以及同同型半胱氨酸的影响。方法:用酶法测血脂,用高效液相色谱法测血浆HCY,在大鼠清醒状态下,测鼠尾的尾动脉收缩压,观察两组自发性高血压大鼠(卡托普利单用组,左旋精氨酸+牛磺酸+卡托普利三药合用组)在用药前后各指标的变化。结果:①经过四周药物治疗,合用组血压下隆比卡托普利组明显(P<0.01)。②卡托普利组血脂无降低(P>0.05)。合用组TC和TG均降低,(P<0.005)。③两组HCY均下降。用药前,大鼠血压高低与血浆HCY的浓度无相关性(P>0.05),用药后,血压的下降与血浆HCY浓度的变化无相关性(P>0.05)。结论:①卡托普利与有氨酸、牛磺酸合用对血压、血脂的控制比单用卡托普利。②血压的下降与同型半胱氨酸的下降无相关性(P>0.05)。  相似文献   
30.
Nishio M  Nagata A  Tsurudome M  Ito M  Kawano M  Komada H  Ito Y 《Virology》2004,329(2):289-301
The Sendai virus pi strain (SeVpi) isolated from cells persistently infected with SeV shows mainly two phenotypes: (1) temperature sensitivity and (2) an ability of establishing persistent infection (steady state). Three amino acid substitutions are found in the Lpi protein and are located at aa 1088, 1618, and 1664. Recombinant SeV(Lpi) (rSeV(Lpi)) having all these substitutions is temperature sensitive and is capable of establishing persistent infection (steady state). rSeVs carrying the fragment containing L1618V show both phenotypes. rSeV(L1618V), in which leucine at aa 1618 is replaced with valine, has the ability of establishing persistent infection, but is not a temperature-sensitive mutant, indicating that the ability of a virus to establish persistent infection can be separated from temperature sensitivity. The amino acid change at 1618(L-->V) coexisting with aa 1169 threonine is required for acquirement of a temperature-sensitive phenotype. Three amino acid substitutions are also found in the Ppi protein, but rSeV(Ppi) does not show these phenotypes.  相似文献   
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