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41.
BACKGROUND: The longer term respiratory effects of massive inhalational exposure of textile printing sprayers to Acramin (the "Ardystil syndrome") are not well established. METHODS: A 12 month follow up of 27 heavily exposed textile sprayers was performed. RESULTS: Twenty one patients experienced cough, 18 dyspnoea, and 17 nose bleeding at initial exposure, with histological evidence of organising pneumonia in 13 cases, radiological abnormalities detected by computed tomographic scanning in 20 cases, and diminution of diffusion capacity to below 80% of predicted in seven cases. At one year after exposure symptoms persisted in 15 cases, radiological alterations in six, and diffusion capacity was reduced in nine. CONCLUSIONS: Whilst most of our patients showed improvement at one year, evidence of persistent lung involvement was present in an appreciable minority of exposed cases.  相似文献   
42.
A Portuguese female, aged 47 years, who had emigrated to Spain, was admitted to the hospital in 1991 for pontine haematoma. The patient, four siblings and her father were affected by a peripheral neuropathy, indicating autosomal dominant inheritance. The patient presented in the 2nd decade with sensory and motor neuropathy beginning in the lower extremities. Alternating constipation and diarrhoea, and urinary incontinence became uncontrollable. She had to be colostomised, and, eventually, confined to a wheelchair from the age of 43. Neurological examination showed bilateral facial involvement, and severe signs of sensory and motor peripheral neuropathy, and later right hemiplegia. There were abnormalities of atrial rhythm and left bundle branch block. Computerised axial tomography and magnetic resonance images demonstrated left-sided pontine haemorrhage. Nerve conduction studies revealed severe diminution of motor conduction velocity and absence or reduction of amplitude of sensory and motor action potentials. Inanition and a respiratory infection led to her death. Clinical diagnosis was type I familial amyloid polyneuropathy (FAP). Postmortem examination demonstrated amyloid deposits in peripheral nerves, including spinal roots and cranial nerves, leptomeninges, thyroid, breasts, heart, adrenal glands, kidneys, intestines, pancreas, and meningeal and some pontine vascular structures. Advanced pontine haematoma was verified. Cerebral haemorrhage usually occurs with cerebrovascular amyloidosis, but exceptionally with FAP. A minority of patients presenting with CNS haemorrhage showed arteriovenous malformation or embolism [Da Silva Horta and Dias Coelho (1960) Arch de Vecchi Anal Patol Med Clin 31=163–172]. However, amyloid deposition in some small pontine vessels could have played a role in the pathogenesis of haemorrhage in the present case.  相似文献   
43.
Davis  GD; Fulton  RE; Ritter  DG; Mair  DD; McGoon  DC 《Radiology》1978,128(1):133-144
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries.  相似文献   
44.
A comparative study was made on the members of the Grandparents' Club from La Salud locality, Quivicán municipality, in order to assess a host of physical and psychic parameters. The results were positive in relation to smoking, obesity and sedentariness, on the basis of preventive programs put into practice since the implementation of the family doctor plan and the grandparents' clubs. There was evidence of improvement in blood pressure requirements, presence of arthralgia, dyspnea due to efforts, normal walking and a lower mean record in the physical fitness tests. At the end of the period under study, the number of drugs taken by the elderly was lower and, from a psychic point of view the elderly people were more capable, more helpful and in general "better".  相似文献   
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46.
The optic tectum of the pigeon is a highly organized, multilayered structure that receives a massive polystratified afference of at least five different populations of retinal ganglion cells and gives rise to various anatomically segregated efferent systems. The synaptic organization of retino-tectal circuitry is, at present, mostly unknown. To investigate the spatiotemporal profile of synaptic activation produced by differential (electrical and visual) stimulation of the retinal inputs, we performed a high-spatial-resolution current source density analysis in the optic tectum of the anaesthetized pigeon. Electrical stimuli consisted of brief pulses of different durations applied to the optic nerve head, while visual stimuli consisted of light flashes of different intensities. Electrical stimulation generated sinks confined to retinorecipient layers. The temporal structure, spatial location and thresholds of these sinks indicated that they are all due to primary tectal synapses of retinal fibers with different conduction velocities. Sinks evoked by the fastest retinal axons were more superficially located than sinks produced by slower retinal fibers. Visual stimulation, on the other hand, resulted in a more complex pattern of current sinks, with various sinks located in the retinorecipient layers and also well below. Visual stimulation induced action potentials at superficial as well as deep tectal levels. We conclude that electrical stimulation activates most of the populations of ganglion cells as well as their primary tectal synapses, but is unable to elicit a significant activation of secondary tectal synapses. Visual stimulation, on the contrary, activates just some of the incoming retinal populations, but in a way that produces noticeable secondary activation of intratectal circuits. Laminar segregation of retinally evoked tectal activity, as reported here, has also been found in other vertebrates. Similarities and differences with previous studies are discussed.  相似文献   
47.
SGP-1/prosaposin can be secreted or targeted to the lysosomes where it is processed into smaller saposins (A, B, C, and D) required for the hydrolysis of glycosphingolipids. The deficiency of saposins B and C results in variant forms of metachromatic leukodystrophy and Gaucher's disease, respectively, which are characterized by lysosomal storage of undegraded glycosphingolipids. In the nervous system, prosaposin presents trophic activity. A mouse model was recently developed by creating a null allele in embryonic stem cells through gene targeting to investigate the phenotypic diversity of prosaposin mutations and the involvement of this protein in lysosomal storage diseases, and for the development of therapeutic approaches. Mice homozygous mutants die at the age of 35-40 days and neurological disorders contribute to the early demise of the mutant mice. The male reproductive organs in homozygous mutants show several abnormalities, such as a decrease in testis size with reduced spermiogenesis and an involution of the prostate, seminal vesicles, and epididymis. In these animals, the blood levels of testosterone remain normal. In the prostate of homozygous mutants, only the basal epithelial cells appear to be present, while the secretory cells are absent. These findings suggest that prosaposin may be involved in the development and maintenance of the male reproductive organs, as well as, in cellular differentiation.  相似文献   
48.
Aneurysms are uncommon in the pediatric age-group. Unlike adults, in which aneurysms appear after alteration of the arterial wall due to systemic diseases, in children the traumatic etiology has to be considered: blunt trauma may disrupt the arterial wall and cause false aneurysm (pseudoaneurysm). Most aneurysms are asymptomatic, or they present as a pulsatile mass on an arterial traject. Diagnosis is confirmed with Doppler ultrasound and angiography. We present the case of a girl who, after blunt trauma of the right upper limb developed a pulsatile mass on the traject of the right humeral artery. Doppler ultrasound and angiography confirmed aneurysm of the humeral artery. She was successfully treated with surgical resection of the aneurysm and reconstruction of the arterial wall.  相似文献   
49.
Pseudomyxoma peritonei is an unusual condition that has caused much confusion regarding its aetiology, clinical manifestations, treatment and prognosis. It is characterised by mucinous ascites and diffuse mucinous invasions of the peritoneum. Three histological subtypes have been defined: a) disseminated peritoneal adenomucinosis (peritoneal lesions composed of abundant extra-cellular mucin containing scant simple-to-focally-proliferating mucinous epithelium with little cytological atypia or mitotic activity); b) peritoneal mucinous carcinomatosis (peritoneal lesions composed of more abundant mucinous epithelium with the architectural and cytological features of carcinoma); and c) an intermediate group. The different histological subtypes have different prognoses. We report a case of disseminated peritoneal adenomatosis, and discuss its clinical management.  相似文献   
50.
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