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81.
目的:探讨明尼苏达多项人格调查量表(MMPI)及事件相关电位(ERP)在海洛因依赖患者中的临床应用价值。方法:对44例海洛因依赖患者和43例正常健康者分别进行了MMPI及ERP测定,并将两组的结果加以比较。结果:海洛因依赖患者中MMPI测定异常率为63.64%(28/44),其量表中Hs(疑病),D(抑郁),Pd(心理变态)、Pa(偏执)、Pt(精神衰弱),Ma(轻躁狂)分显著高于对照组(P<0.01)。海洛因依赖患者ERP测定异常率为52.27%(23/44),其中N2波及P3波(即P300)潜伏期较对照组明显延长,波幅也降低,两组间比较差异有显著意义(P<0.01)。结论:MMPI及ERP电位对海洛因依赖患者临床诊治及预后判断有较高的价值。  相似文献   
82.
目的:探讨了血清可溶性白细胞介素-2受体(SIL-2R)和半胱氨酰白三烯(LTS)水平在支气管肺炎患儿治疗前后的变化及意义。方法:应用ELISA对35例支气管肺炎患儿进行了血清SIL-2R和LTS测定,并与30例正常儿作比较。结果:支气管肺炎患儿在治疗前血清SIL-2R和LTS水平非常显著地高于正常儿组(P〈0.01)。治疗后2周后血清SIL-2R和LTS水平与正常儿比较无显著性差异(P〉0.05)。结论:检测支气管肺炎患儿血清中SIL-2R和LTS水平可作为病情预后判断的重要指标。  相似文献   
83.
This paper shows the importance of using realistic cell shapes with the proper geometry and orientation to study the mechanisms of direct cellular effects from radiofrequency (RF) exposure. For this purpose, the electric field distribution within erythrocyte, rod and ellipsoidal cell models is calculated by using a finite element technique with adaptive meshing. The three cell models are exposed to linearly polarized electromagnetic plane waves of frequencies 900 and 2450 MHz. The results show that the amplification of the electric field within the membrane of the erythrocyte shape cell is more significant than that observed in other cell geometries. The results obtained show the dependence of the induced electric field distribution on frequency, electrical properties of membrane and cytoplasm and the orientation of the cell with respect to the applied field. The analysis of the transition of an erythrocyte shape to an ellipsoidal one shows that a uniformly shelled ellipsoid model is a rough approximation if a precise simulation of bioeffects in cells is desired.  相似文献   
84.
The present study was to investigate and evaluate the dynamic changes of calcium homeostasis of soleus muscle spindle for the exploration of the potential mechanisms of muscle spindle degeneration induced by hindlimb unloading. We systematically observed the changes in immunoreactivity of calbindin D28K (CaBP-D28K), intracellular resting calcium in intrafusal fibers of soleus muscle spindle, and the responsiveness of muscle spindles to ramp-and-hold stretches after short- and long-term (3, 7, 14 d) hindlimb unloading. The immunoreactivity of CaBP-D28K started to decrease after 7-d hindlimb unloading, while its decrease was obviously different compared with the control group 14 d following the hindlimb unloading. The resting calcium concentration was increased significantly at 3 d, and reached the peak level 14 d after the hindlimb unloading. The responsiveness of muscle spindles, assessed by investigating Index3-L2, Index3-L3, and Index5, to ramp-and-hold stretches started to decrease during the period of 7-d hindlimb unloading. All Indexs, in particular Index3-L3 and Index5, were significantly decreased at 14 d after the hindlimb unloading. The data suggest the disturbance of calcium homeostasis in intrafusal fibers during the exposure to hindlimb unloading might gradually influence the structure and function of muscle spindles.  相似文献   
85.
STUDY OBJECTIVE: To investigate the cerebral hemodynamic response to verbal working memory following sleep deprivation. DESIGN: Subjects were scheduled for 3 functional magnetic resonance imaging scanning visits: an initial screening day (screening state), after a normal night of sleep (rested state), and after 30 hours of sleep deprivation (sleep-deprivation state). Subjects performed the Sternberg working memory task alternated with a control task during an approximate 13-minute functional magnetic resonance imaging scan. SETTING: Inpatient General Clinical Research Center and outpatient functional magnetic resonance imaging center. PATIENTS OR PARTICIPANTS: Results from 33 men (mean age, 28.6 +/- 6.6 years) were included in the final analyses. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Subjects performed the same Sternberg working memory task at the 3 states within the magnetic resonance imaging scanner. Neuroimaging data revealed that, in the screening and rested states, the brain regions activated by the Sternberg working memory task were found in the left dorsolateral prefrontal cortex, Broca's area, supplementary motor area, right ventrolateral prefrontal cortex, and the bilateral posterior parietal cortexes. After 30 hours of sleep deprivation, the activations in these brain regions significantly decreased, especially in the bilateral posterior parietal cortices. Task performance also decreased. A repeated-measures analysis of variance revealed that subjects at the screening and rested states had similar activation patterns, with each having significantly more activation than during the sleep-deprivation state. CONCLUSIONS: These results suggest that human sleep-deprivation deficits are not caused solely or even predominantly by prefrontal cortex dysfunction and that the paretal cortex, in particular, and other brain regions involved in verbal working memory exhibit significant sleep-deprivation vulnerability.  相似文献   
86.
OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.  相似文献   
87.
Prospective payment systems using the diagnostic related group (DRG) mechanism are being phased in for Medicare inpatient hospital care. The purpose of this study was to examine a common neurosurgical procedure (001), craniotomy without trauma, and characterize the cost dynamics of this DRG. All patients (n = 50) treated in this DRG at the Long Island Jewish Medical Center during 1983 had their financial charges exclusive of physician fees examined. The findings were: (a) each hospital service category had wide charge variances around the mean; (b) emergency (ER) admissions were 200% more expensive than nonemergency (non-ER) admissions; (c) ER admissions seemed to have no greater severity of illness than non-ER admissions, but had a significantly different referral pattern (i.e., admission from the ER to a nonneurosurgical service with a subsequent neurosurgical referral); (d) this DRG when grouped into clinical "subproducts" (i.e., craniotomy for tumor, hematoma, hydrocephalus, aneurysm, benign cyst, and other) showed marked charge differences; and (e) the most expensive 25% of patients had five times higher charges than the least expensive 25% for both ER and non-ER admissions. This type of financial analysis may give surgeons a methodology with which to address the problems of cost containment in a more serious manner.  相似文献   
88.
目的 探讨多药耐药基因(MDR1基因)在人胃癌组织中的表达及其与临床病理的关系。方法 采用逆转录-多聚酶链反应(RT-PCR)法检测了215例手术切除的进展期胃癌组织中的MDR1基因的表达。实验数据采用SAS软件中的χ^2检验和Fisher’s exact P做统计学处理。结果 MDRI基因的阳性率为31.63%(68/215),与年龄、性别、组织学类型、分化程度、淋巴结转移、Borromann分型及TNM分期等无关,但在分化差的肿瘤中有增高趋势,如黏液腺癌及印戒细胞癌中达41.67%及50.00%。结论 化疗前胃癌组织中MDRI基因即存在较高的表达率,这为选用化疗药物和MDR逆转剂提供了参考指标,但不能作为制定化疗方案的唯一指标。  相似文献   
89.
90.
Guan  Xiu-Hao  Xu  Tian-Hua  Chen  Xi  Mu  Qi-Shuang  Suo  Jing-Fei  Xu  Rui-Xue  Chen  John  Xiao  Ting  Xing-Hua  Gao  Chen  Hong-Duo 《Lasers in medical science》2021,36(8):1619-1623
Lasers in Medical Science - This study is to determine the role of the fractional CO2 laser in topical drug delivery and the impact of local immune responses. Experimental rabbit nails were treated...  相似文献   
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