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1.
A 19-year-old immunocompetent man was admitted to hospital with diplopia, nausea, vomiting and change in mental status. The patient had a history of tuberculous meningitis that was diagnosed at another hospital 6 months before the present admission, and at that time anti-tuberculosis treatment was initiated using a first-line drug combination. A computed tomography (CT) scan of the brain revealed non-communicating hydrocephalus. A ventriculo-peritoneal shunt was inserted surgically. Two months later, the patient was hospitalized again for fever, dysphagia and left hemiparesis. At that time, his cranial CT findings were within normal limits; however, magnetic resonance imaging (MRI) revealed an irregular multilocular peripheral contrast-enhancing lesion in the posterior fossa. The abscess was surgically drained. The presence of acid-fast bacilli in the abscess material was demonstrated by Ziehl-Neelsen staining. Mycobacterium tuberculosis grew on Lowenstein-Jensen culture medium, and the strain was found to be resistant to isoniazid. One month after the operation, the patient became quadriparetic. Cervical MRI revealed a cervico-thoracic syringomyelitic cavity, after which a syringoperitoneal shunt was placed. Treatment with four drugs was continued for 10 months, and then treatment with three drugs for a total period of 18 months. The patient recovered, with residual quadriparesis. Even though very rare, isoniazid-resistant M. tuberculosis may be the causative agent of progressive tuberculosis.  相似文献   
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Transplant arteriosclerosis in a rat aortic model.   总被引:6,自引:1,他引:5       下载免费PDF全文
Transplant arteriosclerosis (TA) has emerged as an obstacle to the long-term survival of transplanted organs, especially cardiac transplants. The animal models that have been used to study TA have not been fully characterized with regard to features such as the time course of cell proliferation and the sequence of cell types arriving in the developing intimal lesion. We present a model of TA based on a transplanted segment of abdominal aorta that helps address these questions. Two strains of rats (PVG x DA) underwent orthotopic aortic transplantation without immunosuppression and were killed at 14, 20, 40, and 60 days after transplantation. The within-strain control group displayed minimal evidence of cellular rejection with minimal to absent intimal lesions. In contrast, the allograft group showed a linearly increasing intimal lesion, up through 60 days after transplantation. The mechanism of intimal thickening was by an increase in cell number at the earlier time points with the later deposition of extracellular matrix. The early intimal lesion consisted mostly of mononuclear inflammatory cells (45%) with gradually increasing presence of smooth muscle cells (SMC) in the intima between 20 and 60 days. Conversely, the media showed gradual infiltration by macrophage-type cells with virtual loss of all SMC from the media by 40 days. The proliferative index showed a peak of 6% and 8% at 20 days in both the intima and media, respectively, and was preceded by the presence of macrophages. In fact, most of the proliferating cells at the earlier time points were either monocytes/macrophages, or were immediately adjacent to monocyte-/macrophage-rich regions. This straight artery segment model of transplant arteriosclerosis provides an easily quantifiable system in which the effects of different interventions (e.g., immunosuppressive regimens) can be tested.  相似文献   
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To evaluate the possible effect of pentoxifylline on the acrosomereaction (AR) and its correlation with in-vitro fertilization(IVF), sperm samples obtained from 51 patients who underwentIVF treatment were studied. Acrosome reactions were evaluatedas spontaneous, pentoxifylline-treated and calcium ionophore(A23187) induced, before and after treatment. The correlationof AR with fertilization in vitro in spermatozoa pre-treatedwith pentoxifylline was sought. In cases with failure or verylow fertilization rate (10%) in their previous trials, spermatozoaafter swim-up were treated before insemination. Spontaneousacrosome loss remained low even after treatment (mean ±SD: 8.18 ± 1.74%). Response to A23187 was enhanced significantly(P < 0.001) by pre-treatment with pentoxifylline in 33 controlcases (group A) in which fertilization in vitro was previouslysuccessful without this treatment. Patients with at least twoepisodes of failed fertilization were divided into two groups.In 11 cases (group B), the IVF rate was improved significantly(P < 0.001) by the treatment. This was not observed in sevencases (group C) in which the treatment induced no increase inIVF rate. We achieved nine (27.3%) pregnancies in group A andfive (45.4%) pregnancies in group B. This study demonstratedthat pentoxifylline enhanced A23187 induced the acrosome reactionand this effect was correlated with improvement in IVF rate.  相似文献   
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A 10-year-old male with recurrent skin lesions and chronic infections was found to have a selective deficiency of C1q after functional analysis of all complement components. The addition of highly purified human C1q to the patient's serum restored C1 activity, indicating the presence of C1r and C1s and the absence of C1q. Titration of highly purified C1q with patient serum as a source of C1r and C1s resulted in a linear dose-response curve. The undetectable CH50 activity temporarily returned to normal within a few hours of plasma infusion, but the C1 titres were still only 1–3% of normal. Following plasma administration, the peak of C1q activity was reached after 30 min and returned to undetectable levels within 24 hr. The patient serum was not anti-complementary when incubated with normal serum. Nine members of the family, including the parents and two healthy siblings, were subjected to complement studies and HLA typing. The C1 titres and CH50 activity were found to be normal in all except the paternal grandmother who showed reduced levels of all the complement components. There was no linkage for the gene of C1q deficiency and HLA antigens. Among the various laboratory studies performed, anti-smooth muscle antibodies, immune complexes and anti-HBsAg antibody were found to be positive. The child died of a disease compatible with septicaemia. Post mortem tissue studies by light, fluorescent and electron microscopy have shown the presence of a mesangioproliferative glomerulonephritis.  相似文献   
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BACKGROUND: Mumps vaccine has not yet been included in the routine vaccination programme, for this reason mumps is still one of the most common infections for children in Turkey. One of the major complication of mumps is meningoencephalitis, which although usually heals spontaneously, it may cause neurologic complications. METHODS: This study was undertaken to investigate epidemiologic and demographic characteristics in children with mumps and mumps meningoencephalitis and clinical/laboratory findings in children with mumps meningoencephalitis diagnosed over a 11 year period. A total of 2422 mumps and 135 mumps meningoencephalitis cases were covered in this study which constitutes one of the largest series of mumps meningoencephalitis in the literature. The mean age of mumps and mumps meningoencephalitis cases were 6.6 +/- 2.7 and 7.6 +/- 2.6 years, respectively. RESULTS: There was a male predominance both among the cases of mumps and mumps meningoencephalitis. The age and seasonal distributions were similar in the mumps and mumps meningoencephalitis groups. The most common symptoms of mumps meningoencephalitis were fever (97%), vomiting (94%) and headache (88.8%). The mean cerebrospinal fluid (CSF) total cell count and lymphocyte count were 540 +/- 460/mm(3) and 300 +/- 330/mm(3), respectively. The mean CSF protein and glucose levels were found to be 56.97 +/- 27.94 mg/dL and 53.67 +/- 15.46 mg/dL, respectively. The mean of CSF/blood glucose ratio was 0.53 +/- 0.16. The mean duration of hospitalization in mumps meningoencephalitis cases was found to be 5.1 +/- 2.4 days and this was longer in boys (P < 0.05). CONCLUSION: In patients with mumps meningoencephalitis, higher CSF protein levels and lower CSF glucose/blood glucose ratio were associated with longer hospitalization periods. There was no death.  相似文献   
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Aim: In this population‐based study, we aimed to determine the total sleep duration (TSD), its association with socio‐economic status (SES) and behavioural symptoms among schoolchildren. Methods: A cross‐sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale. Results:  The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms. Conclusion: Decreased total sleep duration is more prominent in boys, older children and children among higher socio‐economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio‐economic status might have a negative effect on both sleep hygiene and psychological well‐being in schoolchildren.  相似文献   
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