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131.
本实验采用性腺摘除或经假摘除手术的两性SD大鼠,其中部分动物分别予以睾酮(T)或雌二醇(E_2),观察它们在急性饥饿或非饥饿状态下血清T_4、TSH与T浓度变化。结果提示急性饥饿可使雄鼠甲状腺合成或分泌T_4和性腺分泌睾酮减少,从而不完全地抑制了雄激素所介导的对垂体TSH分泌的兴奋作用。外源性T替代虽然可以使去势雄鼠血清T浓度恢复正常,但却无兴奋TSH分泌的作用;饥饿组去势雄鼠接受外源性T后血清TSH更为减少。提示外源性T可抑制此组雄鼠垂体TSH合成及(或)释放。  相似文献   
132.
Hereditary sensory and autonomic neuropathy type I (HSAN I) is an autosomal dominant disorder of the peripheral nervous system characterized by marked progressive sensory loss, with variable autonomic and motor involvement. The HSAN I locus maps to chromosome 9q22.1–22.3 and is caused by mutations in the gene coding for serine palmitoyltransferase long chain base subunit 1 (SPTLC1). Sequencing in HSAN I families have previously identified mutations in exons 5, 6 and 13 of this gene. Here we report the clinical, electrophysiological and pathological findings of a proband in a Chinese family with HSAN I. The affected members showed almost typical clinical features. Electrophysiological findings showed an axonal, predominantly sensory, neuropathy with motor and autonomic involvement. Sural nerve biopsy showed loss of myelinated and unmyelinated fibers. SPTLC1 mutational analysis revealed the C133W mutation, a mutation common in British HSAN I families.  相似文献   
133.
The proliferation of sophisticated endovascular interventions is mandating more definitive and comprehensive documentation of atherosclerotic lesions and the results of the interventional devices used in their removal. A technique with a potential to fulfill these goals, intravascular ultrasound imaging (IVUS), was evaluated against pressure gradients, arteriography, and femoral-radial indices in 11 patients with stenotic iliac lesions. The two-dimensional, real-time scans were useful in measuring pre-and posttreatment cross-sectional diameters and luminal areas for procedural assessment. Furthermore, the ultrasound scans clearly identified arterial wall calcifications, iliac veins, soft plague formations, dissections, synthetic graft anastomoses, and intravascular stents, often with definition superior to arteriography. The IVUS technique was useful in selecting interventional therapies, in particular, the need for stent implantation to control intimal flaps. Further, IVUS demonstrated its ability as a substitute for contrast arteriography in a twelfth patient with an iliac stent in whom a protocol-dictated follow-up arteriogram was contraindicated.  相似文献   
134.
Morrison  MC; Lee  MJ; Stafford  SA; Saini  S; Mueller  PR 《Radiology》1990,176(2):574-576
The authors present two cases of percutaneous cecostomy performed with a modified approach previously described for percutaneous gastrostomy and cholecystostomy. T-fastener devices were used to affix the cecum to the anterior abdominal wall; thus, the potential problem of fecal spillage was prevented. In both cases, adequate fecal drainage was provided without complication.  相似文献   
135.
神经外科中高渗盐注射液应用研究进展   总被引:1,自引:0,他引:1  
控制脑水肿和颅内压(ICP)升高是神经外科围手术期治疗的重要组成部分.颅脑创伤、动脉梗塞、静脉高压/梗塞、大脑内出血、蛛网膜下腔出血、肿瘤和术后脑组织水肿的治疗过程中ICP的控制都是决定患者预后的关键因素.虽然利用渗透压脱水药物是控制ICP的最基础的工具,但却缺乏前瞻性研究以指导其运用,高渗盐被认为是甘露醇的替代物,早期的数据表明每种药的用药指征最终取决于ICP的病因.在这篇综述中,我们总结了有关高渗盐(HS)治疗颅内高压的相关数据,以及这些数据和我们有关HS的经验是如何指导目前的ICP治疗的.  相似文献   
136.

Aims

Multiple genetic alterations, including alternative lengthening of telomeres (ALT) and NOTCH mutations, have been described in angiosarcoma. Loss of α‐thalassaemia/mental retardation syndrome X‐linked (ATRX) and death domain‐associated protein 6 (DAXX) expression is frequently associated with the ALT phenotype. Additionally, inhibition of NOTCH signalling induces the development of malignant vascular tumours in mice, indicating a tumour suppressive role of the NOTCH pathway in the pathogenesis of angiosarcoma. The aim of this study was to evaluate the immunohistochemical expression of ATRX, DAXX and NOTCH receptors (NOTCH1 and NOTCH2) in a large cohort of angiosarcomas, and study their clinicopathological and prognostic significance.

Methods and results

One hundred and forty cases of angiosarcoma were stained for ATRX, DAXX, NOTCH1 and NOTCH2. ATRX loss (<10% labelling) was seen in seven of 118 (6%) cases, and was more frequent in deep soft tissue tumours than in other body sites (P = 0.004). Angiosarcomas with ATRX loss were associated with worse event‐free survival than angiosarcomas with retained ATRX expression (P = 0.003). DAXX was retained in all specimens examined. Decreased NOTCH1 expression (≤1+ intensity) was seen in 29 of 123 (24%) cases, and was associated with a cutaneous site of origin (P = 0.013) and advanced disease (P = 0.026). NOTCH2 expression was decreased in 16 of 103 (16%) cases, was associated with visceral tumours (P = 0.001), and correlated with worse disease‐specific survival (P = 0.033).

Conclusions

ATRX, NOTCH1 and NOTCH2 expression varies in angiosarcomas and shows significant correlations with site of origin and poor clinical outcome, thus highlighting the biological heterogeneity within this tumour type.  相似文献   
137.
The objectives were to determine the differences in depressive symptoms and depression between rheumatoid arthritis (RA) and osteoarthritis (OA) patients, and to analyse the contribution of sociodemographic and clinical variables to depression in RA patients. The responses of 60 Egyptian RA patients and 40 patients with OA of the knees to the Symptom Checklist-90-R Depression subscale were compared. The proportions of patients from both groups confirmed by a psychiatric interview to be clinically depressed according to the DSM-III-R criteria were also compared. The contributions of sociodemographic and disease variables to depressive symptoms and clinical depression in RA patients were explored by multiple linear and logistic regression, respectively. RA patients showed significantly higher depression scores than OA patients (P = 0.001). The difference was unaffected by controlling for the effects of age, sex, disease duration and the sociodemographic covariates. A depressive disorder was clinically confirmed in 23% of RA patients and 10% of OA patients. The erythrocyte sedimentation rate (ESR), being unmarried and an urban residence were significant predictors of depressive symptoms (P < 0.05), while being unmarried (P < 0.05, OR = 2.1) and HAQ disability (P < 0.01, OR = 3.8) were significant predictors of clinical depression in RA patients. RA patients have significantly more depressive symptoms and tend to be more clinically depressed than OA patients. The contribution of some sociodemographic and clinical variables to depression in RA patients was modest, albeit significant.   相似文献   
138.
目的探讨家庭雾化吸入治疗反复喘息患儿的疗效。方法前瞻性分析2012-2013年住院治疗的反复喘息患儿316例,按照是否进行家庭雾化规范治疗分为家庭雾化吸入组和非家庭雾化吸入组。观察家庭雾化吸入治疗反复喘息患儿,能否降低再次住院率、应用全身糖皮质激素及抗生素使用率。结果家庭雾化吸入组198例,随访1年当中其再次住院率为20.2%,门急诊就诊率为66.6%,应用全身糖皮质激素16.6%,应用抗生素65.6%,有症状天数14±5.2天,明显低于非家庭雾化吸入组,差异有统计学意义(P0.05),而两组间一年的医疗费用无统计学差异(P0.05)。结论家庭雾化吸入治疗,可降低反复喘息患儿再次住院率、门急诊就诊率、有症状天数及应用全身糖皮质激素、抗生素治疗次数而一年的医疗费用无增加。  相似文献   
139.
140.
Extracted human teeth have been used to practice operative techniques for a very long time. As a natural surrogate for a live tooth in vivo, their use has traditionally been very important for the development of skills in trainee dentists, as well as their qualified colleagues who wish to practise existing or new skills. As synthetic alternatives develop greater authenticity, alongside a society in which many retain their natural dentition well into old age, the current paradigm relating to how extracted teeth in dental education are used needs to be revisited. An ethical and legal dilemma that must be addressed within dental education relates to where and how teeth may be sourced. This article will seek to question whether there is a legal or ethical requirement to gain consent for the use of extracted teeth from patients, as well as exploring the status of whether extracted dental tissue can be considered to be the property of either patient or surgeon. Whilst synthetic alternatives are being utilized more frequently in education, it is unlikely that they will completely replace extracted natural teeth in the immediate future. It is therefore imperative that their use complies with legal doctrine and contemporary ethical thought.  相似文献   
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