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51.
Endocardial monophasic action potentials (MAPs) were recorded at the right ventricular apex in a patient with QTU prolongation and torsade de pointes (TdP) in association with marked bradycardia and hypokalemia. There was a distinct hump on phase 3 repolarization of the MAPs characteristic of early afterdepolarizations (EADs), which was associated with marked prolongation of the QTU interval on the surface electrocardiogram. EAD amplitude was bradycardia dependent, and there was a strong correlation (r = 0.91) between the preceding RR interval and the amplitude of the EAD (percent of MAP amplitude). Intravenous administration of lidocaine or right ventricular pacing suppressed the ventricular premature complexes and TdP in association with the suppression of the EADs on the MAPs. Furthermore, these EADs were not recorded on the MAPs 1 month later when the QTU prolongation and TdP had disappeared. These findings suggest that the TU abnormality and QTU prolongation responsible for TdP were due to bradycardia-dependent EADs.  相似文献   
52.
We investigated the relationship between the levels of granulocyte elastase α1-proteinase inhibitor complex (E-α1-PI) in plasma and severe intraventricular hemorrhage (IVH) in very low birthweight infants. The concentrations of E-α1-PI and the ratio of the concentrations of E-α1-PI to polymorphonuclear leucocyte counts within 24 h of birth in infants with severe IVH were significantly higher compared with those in infants without severe IVH. E-α1-PI seems to be a useful indicator of IVH.  相似文献   
53.
Background : Non‐mosaic Klinefelter patients are generally azoospermic and there is no therapy to improve the spermatogenesis. Some patients have a few spermatozoa in their ejaculates, which can be used for intracytoplasmic sperm injection (ICSI), but only a few cases resulting in a successful birth have been reported. Methods : Out of 52 non‐mosaic 47,XXY Klinefelter patients, four cases having spermatozoa in their ejaculates were retrospectively studied. Results : Intracytoplasmic sperm injection was performed in three cases using their ejaculates and resulted in one chemical abortion and one death in utero (8 weeks). Using testicular sperm, one patient had a healthy baby with a normal karyotype. Conclusion : Some non‐mosaic Klinefelter patients have ejaculated sperm that can result in a successful birth following ICSI. However, the birth rate is very low compared with the fertilization rate, suggesting increased risk of chromosomal abnormalities.  相似文献   
54.
55.
We report the case of a 3 year old boy who exhibited recurrent serious infections with a transient imbalance of IgG subclass in the second year of life. He suffered from pneumococcal meningitis at 3 months, hepatitis at 9 months, and purulent arthritis at 11 months of age. The second episode of pneumococcal meningitis occurred at 14 months. Serum IgG level was normal for age. Low level of IgG2, undetectable level of IgG4 and negligible level of pneumococcus-specific IgG1-G2 antibodies were found. No other primary immunodeficiency was apparent. Serum IgG2-G4 levels but not pneumococcus-specific IgG1-G2 titers increased by the age of 30 months. At that time, he was inoculated with a polyvalent pneumococcal vaccine along with acellular diphtheria-pertussis-tetanus vaccine. He acquired the immunity against these agents, and had no episodic infections in the following 2 years. This observation stresses the existence of transient IgG subclass deficiency associated with delayed development of the anti-polysaccharide antibody response.  相似文献   
56.
Summary. The effectiveness of postoperative radiotherapy and adjuvant chemotherapy was examined for patients with uterine cervical squamous cell carcinoma. Whole pelvis irradiation is unnecessary for patients with less than 2/3 of depth of cervical local involvement without pelvic regional lymph node metastases. Adjuvant chemotherapy with tegafur [l-(2-tetrahydrofuryl)-5-fluorouracil] (600 mg/day) has failed to improve the survival of patients with positive lymph node metastases.  相似文献   
57.

Purpose

Approximately 15 to 20% of infertile men have azoospermia. In the Y chromosome a deletion, termed the azoospermic factor, has been found in some cases of idiopathic azoospermia. We investigate the relationship of factors in autosomal chromosomes (HLA class I antigens) to spermatogenesis failure in idiopathic azoospermia.

Materials and Methods

We evaluated 65 infertile Japanese men with idiopathic azoospermia. The frequency of the HLA allele reported in 1,216 healthy Japanese men was used as a control. HLA class I typing was performed by the National Institutes of Health standard serological method or polymerase chain reaction-sequence specific primer analysis. Allele frequencies were calculated. We determined statistical significance in the frequency of each allele in patients and controls using the chi-square test. The relationship of HLA antigens to idiopathic azoospermia was expressed as relative risk.

Results

In Japanese men with idiopathic azoospermia the frequency of HLA-A33, B13 and B44 was significantly increased compared with controls. The relative risk of HLA-B44 was 8.4, an extremely high value compared with that of other diseases and HLA antigens.

Conclusions

We suggest that HLA class I antigens are important genetic markers that represent a risk factor for idiopathic azoospermia.  相似文献   
58.
59.
In order to clarify the mechanism of pulmonary fibrosis, we examined the functional changes of lung fibroblasts in bleomycin (BLM)-induced pulmonary fibrosis. Lung fibroblastic cells were obtained from rat lungs after an intratracheal treatment of BLM or saline. The spontaneous proliferation of BLM-treated rat fibroblasts (BRF), which was estimated by 3H-TdR incorporation and direct cell counting, was significantly more rapid than that of normal saline-treated rat fibroblasts (NRF). Next, we investigated prostaglandin (PG) E2 synthesis by BRF and NRF, with or without stimulation by interleukin (IL)-1 alpha, and found that PGE2 production by BRF was significantly less than that by NRF. There was no significant difference in cyclooxygenase (COX) activity and COX-2 mRNA level between BRF and NRF, indicating that the change in PGE2 production was independent of COX, a rate-limiting enzyme for the production of PGE2. These results suggest that the proliferation of fibroblasts is down-regulated by PGE2 released from themselves in normal lungs in an autocrine fashion, thus the decreased PGE2 production observed in lung fibroblasts from rats with BLM-induced pulmonary fibrosis may result in the excessive fibroblast proliferation in this disorder. Overall, these findings throw some light on the mechanism of development of BLM-induced pulmonary fibrosis.  相似文献   
60.
The aim of this study was to investigate the developmental characteristics of the mandibular condyle in sequential phases at the gene level using in situ hybridisation. At d 14.5 of gestation, although no expression of type II collagen mRNA was observed, aggrecan mRNA was detected with type I collagen mRNA in the posterior region of the mesenchymal cell aggregation continuous with the ossifying mandibular bone anlage prior to chondrogenesis. At d 15.0 of gestation, the first cartilaginous tissue appeared at the posterior edge of the ossifying mandibular bone anlage. The primarily formed chondrocytes in the cartilage matrix had already shown the appearance of hypertrophy and expressed types I, II and X collagens and aggrecan mRNAs simultaneously. At d 16.0 of gestation, the condylar cartilage increased in size due to accumulation of hypertrophic chondrocytes characterised by the expression of type X collagen mRNA, whereas the expression of type I collagen mRNA had been reduced in the hypertrophic chondrocytes and was confined to the periosteal osteogenic cells surrounding the cartilaginous tissue. At d 18.0 of gestation before birth, cartilage-characteristic gene expression had been reduced in the chondrocytes of the lower half of the hypertrophic cell layer. The present findings demonstrate that the initial chondrogenesis for the mandibular condyle starts continuous with the posterior edge of the mandibular periosteum and that chondroprogenitor cells for the condylar cartilage rapidly differentiate into hypertrophic chondrocytes. Further, it is indicated that sequential rapid changes and reductions of each mRNA might be closely related to the construction of the temporal mandibular ramus in the fetal stage.  相似文献   
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