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101.
Here we report familial balanced translocation (46,XY,t(8;9)(p10;p10) inherited by two brothers from the father. The first subject, 33 years old, was examined after 3 years of childless marriage. Semen analysis showed severe oligozoospermia, hypomotility and teratozoospermia. His brother, 29 years old, volunteered to join this study. He had not yet tried to start a family. Semen analysis showed dyspermia, but the condition was much less serious than his brother's. In both subjects, the secretory function of the epididymis and the genital tract accessory glands did not seem to be affected by this particular translocation. This case report highlights the importance of cytogenetic analysis in dealing with infertile patients suffering from severe dyspermia apparently sine causa. This is particularly the case when certain Assisted Reproductive Technology (ART) programs are recommended, where natural selection of the sperm no longer takes place (e.g. ICSI). The possible risk of an increase in fetal chromosomal abnormalities would suggest genetic counselling in all such situations.  相似文献   
102.
Cine magnetic resonance with dobutamine following a myocardial infarct   总被引:2,自引:0,他引:2  
PURPOSE: Dobutamine cine MRI is a new diagnostic imaging technique in the pretreatment (revascularization) assessment of myocardial infarction patients. We report the results of a comparative study of the diagnostic yield of dobutamine cine MRI with that of stress echocardiography in the assessment of viable myocardium. We also propose a new method for analysis of cine MR images, employing digital subtraction, aimed at decreasing subjectivity in the quantitative assessment of myocardial wall thickening. MATERIAL AND METHODS: Twenty-six patients (21 men and 5 women) with a history of myocardial infarction who were scheduled for revascularization were submitted to stress echocardiography and dobutamine cine MRI to evaluate contractile recovery of the segments considered akinetic or hypokinetic at baseline echocardiography. Dobutamine was administered in growing doses (5, 10, 15 gamma/kg/min). We considered 16 segments of the left ventricle in each patient. We performed a quantitative analysis of systolic wall thickening on individual cine MR frames both by manual measurements and by digital subtraction. RESULTS: In the 416 segments studied, we found 307 normokinetic, 64 scarred and 45 viable segments with stress echocardiography, versus 302 normokinetic, 83 scarred and 31 viable segments with dobutamine MRI. Wall thickening analysis on Cine MR images showed 268 normal, 68 scarred and 80 viable segments, versus 274 normal, 58 scarred and 84 viable segments with digital subtraction. Three months after revascularization 15 patients were examined to check contractile recovery of the segments considered as viable. Echocardiography had 79% sensitivity and 97% specificity, while cine MRI had 96% and 86%, respectively. Quantitative assessment of systolic wall thickening by cine MRI and digital subtraction had 96% sensitivity and 91% specificity, with no statistically significant differences between the two techniques. In patients with anteroseptal wall myocardial infarction stress echocardiography had 75% sensitivity and 97% specificity. In the subgroup of 13 patients with diaphragmatic or inferior wall infarction echocardiography sensitivity dropped to 68%, versus 96% of cine MRI, but its specificity was higher, namely 97 versus 86%. CONCLUSIONS: In anteroseptal infarction, echocardiography permits to distinguish viable myocardium and scarred myocardial tissue with good sensitivity and specificity, but cine MRI performs better. In inferolateral or diaphragmatic infarction, cine MRI has much higher sensitivity than stress echocardiography and thus makes the technique of choice to evaluate viable myocardium in these sites. The digital subtraction technique is as accurate as manual measurements, but reduces the error rate and permits quicker evaluation, particularly in subendocardial thickening.  相似文献   
103.
BACKGROUND AND PURPOSE: Segmental spinal dysgenesis (SSD) is a rare congenital abnormality in which a segment of the spine and spinal cord fails to develop properly. Our goal was to investigate the neuroradiologic features of this condition in order to correlate our findings with the degree of residual spinal cord function, and to provide insight into the embryologic origin of this disorder. We also aimed to clarify the relationship between SSD and other entities, such as multiple vertebral segmentation defects, congenital vertebral displacement, and caudal regression syndrome (CRS). METHODS: The records of patients treated at our institutions for congenital spinal anomalies were reviewed, and 10 cases were found to satisfy the inclusion criteria for SSD. Plain radiographs were available for review in all cases. MR imaging was performed in eight patients, one of whom also underwent conventional myelography. Two other patients underwent only conventional myelography. RESULTS: Segmental vertebral anomalies involved the thoracolumbar, lumbar, or lumbosacral spine. The spinal cord at the level of the abnormality was thinned or even indiscernible, and a bulky, low-lying cord segment was present caudad to the focal abnormality in most cases. Closed spinal dysraphisms were associated in five cases, and partial sacrococcygeal agenesis in three. Renal anomalies were detected in four cases, and dextrocardia in one; all patients had a neurogenic bladder. CONCLUSION: SSD is an autonomous entity with characteristic clinical and neuroradiologic features; however, SSD and CRS probably represent two faces of a single spectrum of segmental malformations of the spine and spinal cord. The neuroradiologic picture depends on the severity of the malformation and on its segmental level along the longitudinal embryonic axis. The severity of the morphologic derangement correlates with residual spinal cord function and with severity of the clinical deficit.  相似文献   
104.
The intrathoracic manifestations of neurofibromatosis-I are protean and can, on occasion, mimic those of malignancy. Many of the intrathoracic findings are characteristic of the disease and can be expected to be present. Knowledge of the full spectrum of radiologic findings can thus be useful in preventing diagnostic error. Furthermore, an unexpected finding, such as rapid growth of a neural tumor, should be recognized as an atypical feature (suspicious for malignant degeneration) and result in further evaluation.  相似文献   
105.
The authors describe the results of an application of the surgical technique called ASTRA (anterior sagittal transrectal approach) in a 16-year-old girl with recurrent urethro-vaginal fistula. The young girl had a posttraumatic urethro-vaginal fistula. It recurred after 4 operations by a direct vaginal approach before definitive correction with the ASTRA. Three years after the operation the patient has remained well with complete healing and no fistula recurrence confirmed by a voiding cystourethrogram and urodynamic and rectal manometric tests. This report suggests that ASTRA is a useful method of treating acquired or developmental anomalies of the perineal region.  相似文献   
106.
In binding assays, both dynorphin B and alpha-neoendorphin are relatively selective for the kappa1b site, unlike U50,488H which has high affinity for both kappa1a and kappa1b sites. In vivo, U50,488H, dynorphin B and alpha-neoendorphin analgesia are reversed by the kappa1-selective antagonist, nor-binaltorphimine (norBNI). Antisense mapping the three exons of KOR-1 revealed that probes targeting all three exons blocked U50,488H analgesia, as expected. However, the selectivity profile of dynorphin B and alpha-neoendorphin analgesia towards the various antisense oligodeoxynucleotides differed markedly from U50,488H, implying a different receptor mechanism of action.  相似文献   
107.
The olivocerebellar system is characterised by a precise topographical organisation, in which distinct subsets of inferior olivary axons project to neurochemically heterogeneous Purkinje cell subpopulations, arranged into parasagittally oriented compartments in the cerebellar cortex. Adult climbing fibres and Purkinje cells are linked by a one-to-one relationship, which is established during postnatal development after a transitory phase of multiple climbing fibre innervation. The elimination of redundant climbing fibre synapses is thought to be regulated by granule cell-mediated activity-dependent processes. In order to assess whether this developmental remodelling is also important for the construction of the mature olivocerebellar projection map, we examined the hypogranular cerebella of rats treated by means of methylazoxymethanol acetate (MAM) during early postnatal life, in which multiple climbing fibre innervation persists in the adult. In these animals we investigated the distribution of calcitonin gene-related peptide (CGRP)-immunoreactive olivocerebellar axons and arbours during early postnatal development, and the correspondence between climbing fibre strips and zebrin II-defined Purkinje cell bands in the adult. Our results show that: (1) the pattern of CGRP-immunoreactive climbing fibres observed during the first three postnatal weeks is not disrupted after granule cell degeneration; and (2) the alignment between olivocerebellar axon subsets and zebrin II+/- Purkinje cell compartments is normally achieved in adult rats. In contrast, the climbing fibre-Purkinje cell relationship is abnormal, and single arbours innervate restricted dendritic regions of several neighbouring target neurons. These results indicate that the normal distribution of olivocerebellar axon subsets to distinct cerebellar cortical compartments can be established independently from granule cell-mediated remodelling processes. Thus, the postnatal climbing fibre plasticity, which is needed to achieve the normal climbing fibre-Purkinje cell relationship, appears to be confined within the framework of a projection map established during earlier developmental phases.  相似文献   
108.
109.
110.
PURPOSE: Ocular self-injury by psychotic patients is an uncommon cause of ocular morbidity that poses peculiar problems. This report describes a schizophrenic self-injuring patient with scleral rupture and retinal detachment (RD), treated under loco-regional anesthesia. CASE REPORT: A 65-year-old man presented with scleral rupture, hyphema, traumatic lens luxation, vitreous prolapse, vitreous hemorrhage and total RD after deliberately hitting his head. The fellow eye had been successfully operated with scleral buckle surgery for the same reason two years earlier. The patient underwent a two-step surgical procedure under local anesthesia, with repositioning and resection of the uveal prolapse and scleral rupture repair and, separately, lens removal pars plana vitrectomy (PPV), membrane peeling, retinotomy, laser treatment and SiO tamponade. RESULTS: Twelve months after PPV, the cornea was clear, IOP was 16 mmHg, the retina was attached and VA was 20/200. The fellow eye maintained 20/30 VA. CONCLUSIONS: In psychotic patients the intrinsic difficulty of a traumatic RD is combined with systemic illness, no compliance and the risk of recurrence. Although ocular traumas usually require general anesthesia, this patient underwent both interventions under local anesthesia with sedation, because of his psychotic condition and chronic liver failure. Local anesthesia and sedation proved effective in controlling pain and intra-operative compliance even in such a difficult patient. Although it is reasonable to question operating on such patients, we nonetheless believe that every attempt should always be made at gaining useful vision in both eyes since these patients are at a high risk of recurrent ocular trauma.  相似文献   
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