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121.
Catastrophizing has been discussed as a cognitive precursor to the emergence of posttraumatic stress disorder (PTSD) symptoms following the experience of stressful events. Implicit in cognitive models of PTSD is that treatment-related reductions in catastrophizing should yield reductions in PTSD symptoms. The tenability of this prediction has yet to be tested. The present study investigated the sequential relation between changes in a specific form of catastrophizing—symptom catastrophizing—and changes in PTSD symptom severity in a sample of 73 work-disabled individuals enrolled in a 10-week behavioral activation intervention. Measures of symptom catastrophizing and PTSD symptom severity were completed at pre-, mid-, and posttreatment assessment points. Cross-sectional analyses of pretreatment data revealed that symptom catastrophizing accounted for significant variance in PTSD symptom severity, β = .40, p < .001, sr = .28 (medium effect size), even when controlling for known correlates of symptom catastrophizing, such as pain and depression. Significant reductions in symptom catastrophizing and PTSD symptoms were observed during treatment, with large effect sizes, ds = 1.42 and 0.94, respectively, ps < .001. Cross-lagged analyses revealed that early change in symptom catastrophizing predicted later change in PTSD symptoms; early changes in PTSD symptom severity did not predict later change in symptom catastrophizing. These findings are consistent with the conceptual models that posit a causal relation between catastrophizing and PTSD symptom severity. The clinical implications of the findings are discussed.  相似文献   
122.
Ferrant  A; Cogneau  M; Leners  N; Jamar  F; Martiat  P; Michaux  JL 《Blood》1993,81(12):3435-3439
The effectiveness of bone marrow transplantation (BMT) for malignant blood diseases remains limited by the inability of the preparative regimen to eliminate the disease without causing toxicity to normal organs. We have used 52Fe to deliver radiotherapy selectively to the BM. Fourteen patients with hematologic malignancies received 52Fe before a conventional BMT conditioning regimen. The median 52Fe dose was 58 mCi (range, 32 to 85 mCi). As evaluated by quantitative scanning, the median percentage of 52Fe taken up by the BM was 82% (range, 36% to 90%). This resulted in a median radiation-absorbed dose to the BM of 632 rad (range, 151 to 1,144 rad). The median uptake of 52Fe by the liver was 18% (range, 10% to 64%) and the median radiation- absorbed dose to the liver was 239 rad (range, 82 to 526 rad). The median whole body radiation-absorbed dose was 46 rad (range, 22 to 68 rad). No untoward effects were noted after the injections of 52Fe. The patients recovered hematopoiesis without toxicity in excess of that expected with conventional conditioning alone. The median follow-up was 8 months and three patients have relapsed. 52Fe should provide a way to boost the radiation dose to marrow-based diseases before marrow transplantation without increasing toxicity.  相似文献   
123.
目的:调查兰州部队辖区黄河流域老年痴呆及认知障碍的患病率并分析其危险因素。方法:应用《长谷川智力量表》(22~30.5分为轻度异常,10.5~21.5分为痴呆前期,≤10分为痴呆期)和《临床记忆量表》(≤80分为异常),对黄河流域11个地区51个干休所16538人群中2944名60岁以上人员进行调查。采用挨家挨户一对一的的方法开展调查检测,只有2个量表评分均为异常才列为病例组,同时对一般情况、驻地海拔高度、家族遗传史、既往病史、生活习惯等5个方面30个危险因素进行调查,并应用SPSS10.0软件包将调查结果进行多元回归分析。结果:2944名受试者全部完成测试进入结果分析。①老年痴呆的患病率分别为痴呆0.71%,痴呆前期2.11%,轻度异常28.46%,总患病率为31.28%。②多元回归分析结果:脑萎缩(t=-6.304)、重大生活事件(t=-5.328)、高龄(t=-5.415)、无喝茶嗜好(t=-3.802)、脑梗死(t=-3.343)、女性(t=-2.604)、冠心病(t=2.496)、低文化程度(t=1.973)、职业(t=1.965)、高海拔地区(t=1.957)与老年痴呆相关(P均<0.05)。结论:①黄河流域老年痴呆及认知障碍发生与脑萎缩、重大生活事件、高龄、无喝茶嗜好、脑梗死、女性、冠心病、低文化程度、职业、高海拔地区等10种危险因素有关。②结果显示痴呆发病率较低,而痴呆前期及轻度异常发病率较高,所以应重视痴呆前期及轻度异常患者的干预治疗。  相似文献   
124.
While constructing a cDNA library of human embryos, we have isolated a clone homologous to jumonji, a mouse gene required for neural tube formation. We have determined the complete coding sequence of the human homologue (JMJ) and deduced the amino acid sequence of the putative protein. We show here that human and mouse jumonji putative proteins are homologous and present 90% identity. During human embryogenesis, JMJ mRNAs are predominantly expressed in neurons and particularly in dorsal root ganglion cells. They are also expressed in neurons of human adult cerebral cortex. In view of these observations, we propose JMJ as a candidate gene for developmental defects of the central nervous system in the human. The human JMJ gene maps at position 6p24-6p23.   相似文献   
125.
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.   相似文献   
126.
Estrogen (E2), acting via its nuclear receptors, has been implicated in tumor development and growth, particularly in the pathogenesis of breast cancer. E2 also modulates anterior pituitary hormone production and is a potent cell mitogen. Until recently, the actions of E2 were thought to be mediated by a single estrogen receptor (ER) isoform (ER), and currently little is known of the pathophysiological relevance of the ER isoform. The presence of ER mRNA has been demonstrated by RT-PCR in the normal human pituitary, although expression of ER mRNA in human pituitary tumors has not been described. We have used semiquantitative RT-PCR to determine the relative levels of expression of ER mRNA in normal human pituitaries, non-functioning pituitary adenomas and GH-secreting tumors. ER mRNA was detected in normal pituitaries and all pituitary tumors examined. The ratio of ER mRNA to -actin mRNA expression was significantly reduced in non-functioning pituitary tumors (NFTs; 0.92 ± 0.09; mean ± SE; n=23) compared with findings in normal pituitaries (1.56 ± 0.21; mean ± SE; n=5; p<0.05 Student's t-test). Studies of ER protein expression are required to determine the functional significance of reduced ER mRNA expression in NFTs.  相似文献   
127.
In the clinical microbiology laboratory, classical culture and identification methods are rapidly giving way to molecular techniques with many benefits for clinicians and patients. Building on the discovery of the structure of DNA and the genetic code, four main scientific advances have been made which underpin these techniques (hybridisation probes, polymerase chain reaction, the observation that the microbial species signature can be read in the ribosomal genes and also in the proteins). Early discoveries have paved the way for new diagnostic methods, which are rapid, highly sensitive and specific. Automation has provided high throughput for large numbers of clinical specimens combined with reasonable cost. The benefits for the clinician and patient include confirmation of clinical diagnoses and information about antimicrobial susceptibility within hours compared to days for conventional methods. In resource-poor settings, molecular techniques and automated systems may seem unaffordable but new public-private partnerships, initiatives by the World Health Organization and new, innovative laboratory methods offer the promise of benefit for all.  相似文献   
128.
Elsenbruch S  Harnish MJ  Orr WC 《Sleep》1999,22(8):1067-1071
STUDY OBJECTIVES: The study goal was to investigate autonomic activity with heart rate variability analysis during different sleep stages in males and females. DESIGN: The study utilized a 2 Groups (males, females) x 4 States (waking, stage 2 sleep, stage 4 sleep, rapid-eye movement sleep) mixed design with one repeated, within-subjects factor (i.e., state). SETTING: The study was carried out in the sleep laboratory of the Thomas N. Lynn Institute for Healthcare Research. PARTICIPANTS: Twenty-four healthy adults (fourteen females and ten males). INTERVENTIONS: NA. MEASUREMENTS AND RESULTS: All participants underwent polysomnographic monitoring and electrocardiogram recordings during pre-sleep waking and one night of sleep. Fifteen-minute segments of beat-to-beat heart rate intervals during waking, stage 2 sleep, stage 4 sleep, and REM sleep were subjected to spectral analysis. Compared to NREM sleep, REM sleep was associated with decreased high frequency (HF) band power, and significantly increased low frequency (LF) to (HF) ratio. Compared to females, males showed significantly elevated LF/HF ratio during REM sleep. Males also demonstrated significantly decreased HF band power during waking when compared to females. No significant sleep- or gender-related changes in LF band power were found. CONCLUSIONS: The results confirmed changes in autonomic activity from waking to sleep, with marked differences between NREM and REM sleep. These changes were primarily due to stage-related alterations in vagal tone. REM sleep was characterized by increased sympathetic dominance, secondary to vagal withdrawal. The data also suggested gender differences in autonomic functioning during waking and sleep, with decreased vagal tone during waking and increased sympathetic dominance during REM sleep in the males.  相似文献   
129.
Doppman  JL; Brennan  MF; Dunnick  NR; Kahn  CR; Gorden  P 《Radiology》1981,138(3):557-562
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production.  相似文献   
130.
自体骨粉移植修复下颌骨部分缺损的组织学检测   总被引:2,自引:2,他引:2  
目的:通过动物实验进行组织学光镜及扫描电镜检测,观察自体骨粉移植修复下颌骨缺损的愈合过程。方法:实验于2005-05/11在南方医科大学动物实验中心完成,选用12只健康雄性大耳白兔。实验分为两组:一侧为自体骨粉移植组,另一侧为空白对照组,均采用自体左右对照。①缺损模型建立:于双侧下颌骨体部下缘用磨削机器各造成1.0×1.0cm的全层骨缺损。②自体骨粉移植:将所有自体骨粉回填一侧缺损处作为自体骨粉移植组,另一侧缺损旷置作为空白对照组。③分别于术后2,4及8周各处死4只动物,获取整块下颌骨标本作组织学光镜及扫描电镜检测,光镜切片应用苏木精-伊红染色,扫描电镜只观察自体骨粉移植组标本。结果:12只大耳白兔均进入结果分析,无脱失。①两组标本组织学观察结果:自体骨粉移植组术后2周时形成薄层骨痂;4周时为新生的骨小梁,但排列紊乱;8周时骨小梁形成的编织骨已逐渐向板层骨过渡。空白对照组术后8周时骨小梁分布仍稀疏。②自体骨粉移植组标本超微结构观察结果:术后4周骨基质钙化程度提高,大量成骨细胞位于骨陷窝内。缺损间隙逐渐变窄形成多孔较疏松的新骨组织,新生骨小梁形成,新骨超微结构呈“蜂窝状”。8周时骨小梁钙化程度继续升高,形成的板状骨排列出现一定方向性,新生骨组织由多孔疏松的结构向致密性结构转化,新原骨组织基本上融为一体产生骨性结合,髓腔相通。结论:自体骨粉移植修复下颌骨成骨可靠,愈合加快,愈合方式以骨传导爬行替代为主,且应用方法简便。  相似文献   
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