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1.
Beta-thalassemia major (TM) is caused by any of approximately 150 mutations within the beta-globin gene. To establish the degree of chimerism after bone marrow transplantation (BMT), we have performed molecular analysis of beta-globin mutations in 14 patients with TM over a period of 10 years. All patients underwent T cell-depleted allogeneic BMT from HLA-identical related donors, using either in vitro T-cell depletion with CAMPATH 1M and complement or in vivo depletion using CAMPATH 1G in the bone marrow collection bag. To date, at different time periods after BMT, seven patients have some degree of chimerism; six of these patients, all blood transfusion-independent, have donor cells in the range of 70% to 95%, with stable mixed chimerism (MC). The seventh patient has less than 10% donor cells with, surprisingly, only minimal transfusion requirements. The detection of beta-globin gene point mutation, as used here, is a highly specific and sensitive marker for engraftment and MC in patients with thalassemia. In light of its specificity, the method is applicable in all cases of TM, as it is independent of sex and other non-globin-related DNA markers. The high incidence of MC found in our patients may be a consequence of the pre- BMT T-cell depletion. Because MC was associated with transfusion independence, complete eradication of residual host cells for effective treatment of TM and possibly other genetic diseases may prove not to be essential.  相似文献   
2.
A rare case of thymic carcinoma with multiple brain metastasis is reported. In our extensive review of the literature only six of 30 reports of intracranial thymoma metastasis describe multiple metastases. A 38-year-old man presented with signs of raised intracranial pressure that had began 15 days previously. Cranial MRI revealed over 70 cystic lesions in the supra and infratentorial regions. Stereotactic biopsy was planned. On the second day of his admission he deteriorated and died the following day. The autopsy revealed a mass in the mediastinum. In the brain parenchyma were multiple cystic lesions between 0.5 and 3 cm in diameter. Histopathologically they were diagnosed as metastases from the thymic carcinoma. The mean survival with a single brain metastasis is approximately 256 days, whereas with multiple brain metastases it is only 64 days, thus treatment of this tumor demands prompt surgery whenever possible and optimal adjuvant therapy.  相似文献   
3.
OBJECTIVE: The objective of this study was to determine the prevalence of sexual dysfunction in patients with schizophrenia under antipsychotic therapy and to investigate the effect of various parameters on sexual dysfunction. METHOD: A total of 827 stabilized outpatients who met DSM-IV criteria for schizophrenia, were recruited in the study. Arizona Sexual Experience Scale (ASEX) and the subscale on sexual function of the UKU Side Effects Rating Scale were applied at a single interview. RESULTS: In total, 52.6% of the patients had sexual dysfunction, 54.2% reported a low sexual desire and 41.7% reported problems in having an orgasm. Erectile dysfunction and ejaculation problems were seen in 48.1% and 64.2% of the men, respectively; amenorrhea was seen in 24.9% of the women. ASEX score and severity of disease were found to be correlated (p=0.02). Higher ASEX scores were observed in patients who smoked (p=0.01). Men receiving atypical monotherapy had lower ASEX scores than those receiving a combination of atypical and conventional antipsychotics (p=0.017). Patients on combination therapy had more ejaculation problems than the atypical group (p=0.001). Low sexual desire was more prevalent among women using conventional drugs than those on atypical drugs (p=0.004). In linear regression analyses, ASEX was affected significantly and independently by the severity of the disease only in men (p=0.005). CONCLUSION: Our results show that sexual dysfunction is widespread among patients with schizophrenia on antipsychotic medications.  相似文献   
4.
This study was conducted to determine the source and number of primary sensory neurons (PSNs) innervating a mandibular molar tooth of a population of 15-18-week-old Sprague-Dawley rats. The pulpal tissue was exposed to horseradish peroxidase (HRP) pellets for 24 hours. Subsequently the animals were perfusion fixed and the following PSN structures were examined for the presence of HRP-labelled cells: trigeminal (TGs) and cervical dorsal root ganglia (DRGs) and mesencephalic nucleus (MN). Only the TGs contained labelled cells and they thus were the sole source of PSN pulpal innervation. The number of TG cells was highly variable, 49-407, but most of this variability was attributable to insufficient HRP filling of the pulp chamber or leakage of HRP into periapical tissue. Selection of TGs whose respective experimental teeth demonstrated that HRP filled and was restricted to the pulp chamber revealed a narrower range of TG cells providing pulpal innervation to the first molars, 142-288, with an average of 213. A detailed mapping of these cells indicated a somatotopic distribution within the mandibular territory of the TGs. It was concluded that these findings represent TG's contribution to the pulpal innervation of this specific population of rat first molar teeth. This suggests that from animal to animal the density of innervation may be quite variable and it is hypothesized that the sensitivity of the pulp would likewise vary. In addition, these findings may contribute to the explanation of why there is variability in the stimulus strength needed to elicit a pain response in the human dentition.  相似文献   
5.
The Health Council of the Netherlands published a report in which the best procedure and method for recommending health‐based occupational exposure limits (OELs) for inhaled allergens were identified by evaluating the scientific state of the art. Many respiratory disorders in the workplace arise from inhalation of substances which can cause allergy. To protect workers against respiratory allergy, various preventive measures are taken, one of them being reduction of exposure by setting legally binding standards. These are based on health‐based OELs that specify a level of exposure to an airborne substance, a threshold level, below which it may reasonably be expected that there is no risk of adverse health effects. The Council is of the opinion that an OEL should prevent against allergic sensitization, as sensitization plays a crucial biological role and is a prerequisite for the development of allergy. Furthermore, the Council considers it most likely that the exposure level below which no allergic sensitization develops for most allergens is so low, that OELs are difficult to set with the current knowledge and technical feasibilities. An alternative approach is to accept exposure, which carries a small predefined risk in developing allergic sensitization. In addition, it is worth considering periodic screening of exposed workers on allergic sensitization, because timely intervention can prevent worse. The feasibility of periodic screening and what else is needed to comply with the most important criteria, should however be judged case‐by‐case.  相似文献   
6.
In order to determine the positivity rate and genotype of Epstein-Barr virus (EBV) in cases with Hodgkin's disease (HD) in Turkey, 40 tissue specimens from HD patients were analysed. Ten non-lymphoid tissue samples from individuals without any evidence for lymphoma were used as controls. The cases with HD included 33 males and 7 females with a mean age of 28 years. Nodular sclerosis was the most prevalent histological subtype (16/40) followed by mixed cellularity (10/40), lymphocyte predominance (9/40), and lymphocyte depletion (5/40). After histopathological evaluation, deparafinisation and lysis of the specimens, one-stage polymerase chain reaction (PCR) and two-stage (nested) PCR assays were performed with the primers common for both EBV genotypes and the primers specific for EBV types 1 and 2, respectively. EBV DNA was detected in 22 of 40 (55%) cases with HD and in 1 of 10 (10%) control specimens. The distribution of EBV DNA positivity according to the histological subtypes was as follows: 10 of 16 (62.5%) for nodular sclerosis, 3 of 5 (60%) for lymphocyte depletion, 5 of 9 (55.6%) for lymphocyte predominance, and 4 of 10 (40%) for mixed cellularity. Although most of the HD patients were males of 15-34 years of age, there were no significant differences between EBV positivities obtained from different sex and age groups. The rates of EBV genotypes were 82% for type 1, 9% for type 2, and 9% for both types, respectively.  相似文献   
7.
8.
We present a rare case of a placental teratoma found within the fetal membranes of an otherwise normal placenta. Lack of a recognizable umbilical cord and no recognizable skeletal development are used as differential diagnostic criteria for a placental teratoma. In our case, an umbilical cord was absent; nevertheless, the tumor contained two vascular channels covered only by fetal membranes without Wharton's jelly.  相似文献   
9.
BACKGROUND/AIMS: To date direct toxic effects of free oxygen radicals in vivo on pancreatic parenchyma have not been studied thoroughly. We aimed to study: 1) the detailed histopathological changes induced by free oxygen radicals in pancreas; and 2) the preventive effect of intraductal catalase in H2O2-induced acute pancreatitis. METHODOLOGY: Wistar Albine rats were randomized into six groups. 1) First experiment: Bile-pancreatic duct was cannulated close to the liver and perfused through the duodenum with (i) normal saline solution, (ii) iron sulfate (FeSO4), (iii) hydrogen peroxide (H2O2), (iv) hydrogen peroxide and iron sulfate simultaneously. 2) Second experiment: Bile pancreatic duct was perfused either with H2O2 or H2O2 + catalase. Serum amylase and pancreas malondialdehyde levels were measured in both experiments after 3 hours of perfusion period. Tissue samples were obtained for histopathological examinations. RESULTS: 1) First experiment: Intraductal perfusion of FeSO4 or H2O2 or H2O2 + FeSO4 induced acute edematous pancreatitis with focal parenchymal necrosis. At the ultrastructural level, intracytoplasmic formation of vacuoles. fusion of the vacuoles and zymogen granules, and autophagosomes containing cellular organelles were found. Serum amylase and pancreas malondialdehyde levels, and morphological score were significantly higher in these groups than control group (p < 0.001). 2) Second experiment: Catalase perfusion simultaneously with H2O2 decreased the serum amylase and pancreas malondialdehyde levels, and morphological score significantly (p < 0.001) and prevented the desquamation of the columnar epithelium and development of gross edema but not parenchymal necrosis. CONCLUSIONS: Intraductal perfusion of FeSO4 or H2O2 or H2O2 + FeSO4-induced acute pancreatitis with marked light and electronmicroscopic changes. Intraductal perfusion of catalase and H2O2 simultaneously did not prevent or lessen the parenchymal necrosis. These findings have suggested that another mechanism of injury may also play a role in parenchymal injury in oxygen radical-induced acute pancreatitis.  相似文献   
10.
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