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11.
Cortical dendritic pathology in human immunodeficiency virus encephalitis.   总被引:4,自引:0,他引:4  
Previous neuropathological and morphometric studies of the cerebral cortex of patients with human immunodeficiency virus encephalitis (HIVE) have shown a decrease in the population of large neurons, moderate loss in synaptophysin immunoreactivity, and pathological changes in dendrites. To further characterize and quantify alterations in the dendritic tree of neocortical pyramidal neurons, we performed a modified Golgi impregnation technique on Formalin fixed blocks from the frontal cortex of 5 HIVE cases, 5 human immunodeficiency virus seropositive control cases without encephalitis, and 5 human immunodeficiency virus seronegative controls. Apical dendrites of HIVE cases were dilated, vacuolated, and tortuous with decreased length and branching. Basal and oblique dendrites also showed these alterations, but to a lesser extent. Some dendrites presented lacunae and filopodia consistent with remodeling. Computer aided quantification of HIVE cases showed a 40-60% decrease in spine density throughout the entire length of dendrites. Laser confocal imaging of Golgi impregnated sections displayed aberrant spines in regions of abnormal second order dendritic branches. These observations support the role of primary dendritic damage in HIVE in contrast to other neurodegenerative disorders where the primary pathology is presynaptic.  相似文献   
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13.
We have used a mouse model to study the ability of human CFTR to correct the defect in mice deficient of the endogenous protein. In this model, expression of the endogenous Cftr gene was disrupted and replaced with a human CFTR cDNA by a gene targeted 'knock-in' event. Animals homozygous for the gene replacement failed to show neither improved intestinal pathology nor survival when compared to mice completely lacking CFTR. RNA analyses showed that the human CFTR sequence was transcribed from the targeted allele in the respiratory and intestinal epithelial cells. Furthermore, in vivo potential difference measurements showed that basal CFTR chloride channel activity was present in the apical membranes of both nasal and rectal epithelial cells in all homozygous knock-in animals examined. Ussing chamber studies showed, however, that the cAMP-mediated chloride channel function was impaired in the intestinal tract among the majority of homozygous knock-in animals. Hence, failure to correct the intestinal pathology associated with loss of endogenous CFTR was related to inefficient functional expression of the human protein in mice. These results emphasize the need to understand the tissue- specific expression and regulation of CFTR function when animal models are used in gene therapy studies.   相似文献   
14.
Preimplantation genetic diagnosis was performed in 61 day 3 embryos obtained by in-vitro fertilization from seven patient carriers of haemophilia, Marfan's syndrome, Bloch-Sulzemberg syndrome (incontinentia pigmentosa) or X chromosome-linked immune deficiency, retinitis pigmentosa, and FG syndrome, which is characterized by mental retardation and hypotonia. After multiplex polymerase chain reaction, 16 embryos were diagnosed as being unaffected, and these were transferred to the uterus on the following day (day 4). Of these embryos, six (37.5%) implanted, resulting in the delivery of a singleton and a twin pregnancy, a late second trimester miscarriage (twins at week 20) and a first trimester miscarriage at week 8. All the diagnoses were confirmed by amniocentesis. We report for the first time a late day 4 transfer of biopsied human embryos undergoing preimplantation genetic diagnosis. This transfer schedule allows an extra day to perform genetic analyses on single blastomeres and to monitor any adverse effect of the biopsy procedure.   相似文献   
15.
Hereditary cerebral hemorrhage with amyloidosis - Dutch type (HCHWA-D) is an autosomal dominant disease caused by deposition of β-amyloid in the leptomeningeal arteries and cortical arterioles, in addition to preamyloid deposits and amyloid plaques in the brain parenchyma.
The disease is due to a point mutation at codon 693 of the amyloid precursor protein (βPP) gene at chromosome 21. Since this point mutation is diagnostic for HCHWA-D, presymptomatic testing is feasible and offered, together with genetic counselling and psychological support, to subjects at risk. HCHWA-D is clinically characterized by recurrent strokes, in addition to dementia, which can occur after the first stroke but also preceding it. Radiological studies revealed focal lesions (hemorrhages, hemorrhagic and non-hemorrhagic infarctions) and diffuse white matter damage. Diffuse white matter hyperintensities on MRI are an early symptom of HCHWA-D since they have been found on MRI scans of subjects who had not suffered a stroke.
The presence of the diagnostic point mutation makes HCHWA-D a useful model to study the effects of cerebral amyloid angiopathy in vivo. The characteristic pathological abnormalities and its implications for Alzheimer's disease will be discussed in Part II of this article  相似文献   
16.
同种异体黑素细胞移植治疗白癜风   总被引:2,自引:2,他引:0  
卢涛  高天文  刘玉峰  李春英  孙林潮 《医学争鸣》2001,22(12):1147-1147
0 引言 白癜风患者免疫紊乱 ,黑素细胞 (melanocyte,MC)异体移植有可能不被排斥 ,治疗如成功将有很大临床前景 [1 ] .探索同种异体黑素细胞移植后的效果很有意义 .1 病例报告 女 ,2 7岁 ,确诊白癜风 (稳定期 ) ,患者皮肤自幼出现色素脱失斑 ,逐渐增多扩大 . 1996年外用“敏白灵”,前2 mo有效 . 1999- 0 7外用补骨酯酊 ,日服 5 g· L- 1 硫酸铜 10m L和中药 1剂 ,转移因子 4m L ,sc,1· 2 d- 1 .皮损缩小 ,4mo后稳定 .用健康男青年环切的包皮培养 MC,第 4代大约80 %融合时 ,用 2 .5 g· L- 1 胰酶消化 5 min,加入含 2 0 0 g·L- 1小…  相似文献   
17.
Wetzler S  Morey LC 《Psychiatry》1999,62(1):49-59
This article presents an explanation and critique of the rationale for dropping passive-aggressive personality disorder (PAPD) from DSM-IV. The clinical and research literature on PAPD is reviewed along with the historical changes in definition, diagnostic criteria, and usage. PAPD can be reliably diagnosed, is fairly prevalent, and has good internal consistency. Because PAPD is no less valid than other personality disorders, and describes clinical phenomena that are unique among personality disorders, we recommend the reinstatement of PAPD in the official diagnostic nomenclature.  相似文献   
18.
The purpose of this study was to examine the relationship of subtypes and particular clinical features of mood disorders to co-occurrence with specific personality disorders. Five hundred and seventy-one subjects recruited for the Collaborative Longitudinal Personality Disorders Study (CLPS) were assessed with the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) and the Diagnostic Interview for DSM-IV Personality Disorders (DIPD-IV). Percent co-occurrence rates for current and lifetime mood disorders with personality disorders were calculated. Logistic regression analyses examined the effects of clinical characteristics of depressive disorders (e.g., age at onset, recurrence, symptom severity, double depression, and atypical features) on personality disorder co-occurrence. In comparison with other DSM-IV personality disorders, avoidant, borderline, and dependent personality disorders (PDs) were most specifically associated with mood disorders, particularly depressive disorders. Severity and recurrence of major depressive disorder and comorbid dysthymic disorder predicted co-occurrence with borderline and to a lesser extent research criteria depressive personality disorders. The results are consistent with the view that a mood disorder with an insidious onset and recurrence, chronicity, and progression in severity leads to a personality disorder diagnosis in young adults.  相似文献   
19.
PURPOSE: We reviewed the quality and usefulness of single shot intraoperative excretory urography (IVP) for evaluating suspected upper urinary tract trauma at our trauma center. MATERIALS AND METHODS: Between 1990 and 1997 single shot intraoperative IVP for staging renal injuries was performed in 50 patients in whom clinical instability and/or major associated injuries mandated an intraoperative study. Contrast material (2 ml/kg) was injected intravenously and images were obtained after 10 minutes. The quality and usefulness of each study were scored by a single attending urologist on a scale of 1-worst to 5-best. RESULTS: Intraoperative study quality was generally good (average score 3.84). The information obtained was generally considered useful for determining urological treatment (average score 3.96). In 16 patients (32%) intraoperative IVP findings safely obviated renal exploration. No contrast medium reactions were noted and no complications developed that were attributable to intraoperative IVP. CONCLUSIONS: Intraoperative single shot, high dose IVP is safe, efficient and of high quality in the majority of cases when performed as recommended. This study often provides important information that facilitates rapid and accurate decision-making. Intraoperative IVP is a useful tool for guiding the exploration of penetrating renal injuries and confirming blunt renal injuries that may be safely observed.  相似文献   
20.
Radiographic staging of renal injuries   总被引:12,自引:1,他引:11  
Radiographic staging of renal injuries is the orderly process of establishing an immediate diagnosis so as to expedite effective treatment. Adult patients with gross hematuria or microhematuria associated with shock should undergo urgent imaging. Computerized tomography (CT scan) is the study of choice for evaluation of stable adult and pediatric patients with suspected renal trauma. Those in need of immediate surgical intervention are best evaluated by one-shot intravenous pyelogram (IVP) to determine the extent of the injured kidney and to document the normal function of the contralateral unit. Successful management of renal trauma is guided to a major degree by appropriate renal imaging.  相似文献   
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