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691.
MJ Cherian MH Dahniya N Al-Marzouk E Osmanagich A Abul A Haider 《Journal of Medical Imaging and Radiation Oncology》1998,42(4):309-312
Two cases of primary pulmonary tuberculosis presenting as mass densities and simulating neoplasms in children are reported. This manifestation has not been previously reported in children. It probably represents an unusual immunological response to the mycobacterium. 相似文献
692.
A total of 121 infants entered a cohort serological study of primary infections with herpes-viruses. All of them had seven samples of blood available: the first sample was taken soon after birth, the other six were taken at 1, 2, 3, 6, 12, and 14 months of age. One sample of maternal blood was collected immediately after delivery. All blood samples were tested for antibodies against cytomegalovirus, Epstein-Barr virus, and human herpesvirus-6 (HHV-6). Primary cytomegalovirus infection occurred early; the cumulative infection rates were 1.7%, 8.3%, 18.3%, 25%, 52.5%, and 65% by the ages of 1, 2, 3, 6, 12, and 14 months, respectively. Epstein-Barr virus infection was not seen before 3 months of age and slowly emerged thereafter, reaching a cumulative rate of 1.7%, 11.6%, 21.5% at the ages of 6, 12, and 14 months, respectively. Primary HHV-6 infection was also a rare event in the first three months of life, but peaked between 6 and 12 months of age. No detectable risk factors were associated with primary Epstein-Barr virus or HHV-6 infection. The risk factors associated with cytomegalovirus infection included breast feeding, fewer children in household, and care by a babysitter. 相似文献
693.
MH Kang 《Clinical genetics》2008,73(5):424-425
Chymotrypsin C (CTRC) variants that diminish activity or secretion are associated with chronic pancreatitis
Jonas Rosendahl et al. (2008)
Nature Genetics 40: 78–82 相似文献
Jonas Rosendahl et al. (2008)
Nature Genetics 40: 78–82 相似文献
694.
用抗大鼠视网膜神经节细胞诱向因子(Retinal ganglion neuronotrophic factor,RGNTF)单克隆抗体对临床手术切除的4例人视网膜母细胞瘤(Rb)和培养的人(Y-79)视网膜瘤细胞株进行了免疫细胞化学染色。结果显示,瘤细胞有较强的反应阳性。为进一步证实,用Y-79细胞株制备Rb细胞提取液作快速电泳,并转移至PVDF膜,用RGNTF单克隆抗体进行Western印迹反应,结果表明,RGNTF单抗仅在Rbe电泳的30kD蛋白带呈现单一的阳性反应带,其余蛋白带皆为阴性。为识别Rb瘤细胞内存在的尽GNTF与大鼠顶盖提取液中的RGNTF是否享有相同的生物效应,用辣根过氧化物酶(HRP)逆行标记的初生大鼠视网膜神经节细胞(RGC)培养在Rb提取液(Rbe)和顶盖提取液(Te)电泳后的凝胶片上48小时。结果发现HRP阳性的视网膜神经节细胞只存活在Rbe(共有18条蛋白带)与Te(共有25条蛋白带)中的30kD蛋白带上,表明Rbe中的RGNTF对RGC有同样生物效应。以上结果说明,人视网膜母细胞瘤内存在与大鼠相同的RGNTF,并提示Rb肿瘤细胞的超常生长可能与其自身产生的RGNTF有关。 相似文献
695.
696.
Effects of ex vivo GDNF gene delivery on the degeneration of motoneurons were studied in the G1H transgenic mouse model of familial ALS carrying a human superoxide dismutase (SOD1) with a Gly93Ala mutation (Gurney et al., 1994). Retroviral vectors were made to produce human GDNF or E. coli beta-galactosidase (beta-Gal) by transient transfection of the Phoenix cell line and used to infect primary mouse myoblasts. In 6-week-old G1H mice, 50,000 myoblasts per muscle were injected bilaterally into two hindlimb muscles. Untreated G1H and wild-type mice served as additional controls. At 17 weeks of age, 1 week before sacrifice, these muscles were injected with fluorogold (FG) to retrogradely label spinal motoneurons that maintained axonal projections to the muscles. There were significantly more large FG-labeled alpha motoneurons at 18 weeks in GDNF-treated G1H mice than in untreated and beta-Gal-treated G1H mice. A morphometric study of motoneuron size distribution showed that GDNF shifted the size distribution of motoneurons toward larger cells compared with control G1H mice, although the average size and number of large motoneurons in GDNF-treated mice were less than that in wild-type mice. GDNF also prolonged the onset of disease, delayed the deterioration of performance in tests of motor behavior, and slowed muscle atrophy. Quantitative, real-time RT-PCR and PCR showed persistence of transgene mRNA and DNA in muscle for up to 12 weeks postgrafting. These observations demonstrate that ex vivo GDNF gene therapy in a mouse model of FALS promotes the survival of functional motoneurons, suggesting that a similar approach might delay the progression of neurodegeneration in ALS. 相似文献
697.
MH Motamedi N Eshghyar SM Jafari E Lassemi F Navi FM Abbas S Khalifeh PS Eshkevari 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):e39-e43
OBJECTIVE: This study aimed to assess the demographic characteristics of peripheral giant cell granulomas (PGCGs) and central giant cell granulomas (CGCGs) in patients treated at our centers. STUDY DESIGN: This 12-year retrospective study was based on existing data. Files of patients from 1993-2004 with a definite diagnosis of PGCGs and CGCGs from the oral pathology departments of our universities were assessed. Information regarding age distribution, gender, the jaw involved, the presenting area of the lesion, surgical treatment, and recurrence was documented. RESULTS: During the study period, 204 patients with CGCGs were treated. The patients with CGCGs varied in age from 5 to 72 years, and the mean age patients was 23.72 years. Among these, 127 cases (62.87%) occurred in the second and third decades of life. One hundred thirty cases (63.75%) occurred in females and 74 (36.25%) in males. Ninety cases (44.1%) presented in posterior parts of the jaws. One hundred forty-four cases (70.58%) appeared in the mandible. Peripheral GCGs presented in 575 patients, who varied in age from 2 to 85 years with a mean age of 31.02 years. Among these, 297 cases (51.65%) occurred in females and 278 (48.34%) in males. Four hundred sixty-seven cases (81.2%) occurred in the first five decades of life, and 352 cases (61.21%) appeared in the mandible. CONCLUSIONS: Giant cell granulomas comprised 9.29% of oral lesions. Peripheral GCG lesions occurred more than 2 times more frequently than CGCGs. Central GCGs occurred about 2 times more frequently in females, whereas PGCGs had an equal prevalence in both genders (P < .05). The mean age for patients with CGCGs was less than patients with PGCGs (P < .05). Central GCGs involved the mandible approximately 2 times more frequently than the maxilla (P < .05). However, when presenting in the maxilla, CGCGs most frequently presented in the area anterior to the canines (P < .05). Peripheral GCGs involved the mandible approximately 1.5 times more frequently than the maxilla (P < .05). Thorough curettage was the main treatment modality used. There were 9 cases (4.41%) of recurrence of CGCGs and 8 cases (1.39%) of recurrence of PGCGs documented during the follow-up period (ranging from 1-12 years). 相似文献
698.
699.
DM Patel PG Rhodes MH LeBlanc GR Graves C Glick J Morrison 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(8):874-879
This prospective study was designed to identify the role of postnatal penicillin prophylaxis in the prevention of neonatal group B streptococcus (GBS) infection. We studied 10 998 infants. Of these, 5389 were in the penicillin prophylaxis group (PP) and 5609 infants did not receive penicillin prophylaxis (NPP). Infants were allocated to treatment by month of birth, alternating 3-mo blocks or 2-mo blocks to the two groups after the first block was randomly assigned. The use of PP reduced the incidence of clinical sepsis (1.7% PP versus 2.5% NPP, p < 0.01), GBS infection (0.4% PP versus 0.9% NPP, p < 0.001) and deaths from sepsis (0.1% PP versus 0.3% NPP, p < 0.05). We conclude that the routine use of postnatal penicillin prophylaxis appears to be effective in reducing the incidence of clinical sepsis and death from sepsis in neonates. 相似文献
700.
Anton F Lenssen Yvonne HF Crijns Eddie MH Waltjé Mike JA van Steyn Ruud JT Geesink Piet A van den Brandt Rob A de Bie 《BMC musculoskeletal disorders》2006,7(1):71-9