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11.
cDNAs encoding human parainfluenza virus type 4B (hPIV-4B) hemagglutinin neuraminidase (HN) protein were cloned and the nucleotide sequences were determined. A high degree of identity (81.4%) was observed between the nucleotide sequences of hPIV-4A and -4B HN proteins, and an 87.3% identity was found between the deduced amino acid sequences. This degree of identity is considered to be greater than immunological similarity between hPIV-4A and -4B HN proteins determined using monoclonal antibodies. To elucidate the causes of the antigenic difference between HN proteins of hPIV-4A and -4B, we constructed three cDNAs of hPIV-4B HN whose potential N-glycosylation sites were partially or completely the same as in hPIV-4A HN cDNA. We compared the antigenicity of the expressed wild-type and mutant proteins, and found that the antigenicities of the mutant hPIV-4B HN proteins were more similar to the hPIV-4A HN protein than to the non-mutant hPIV-4B HN protein. This study indicated that the antigenic diversity between hPIV-4A and -4B was partly caused by deletion or creation of glycosylation sites, showing that the point mutations resulting in deletion or creation of glycosylation sites is one of the initial steps leading to the division of virus into subtypes. Received: 21 January 2000  相似文献   
12.
Early onset familial Alzheimer's disease with spastic paraparesis (FAD-SP) has been associated with mutations of the presenilin 1 gene (PSEN1). We report a pedigree of FAD-SP due to a novel missense mutation of PSEN1 (Y154N). The symptoms of the proband were characterized by presenile dementia in her 40s, preceded by spastic paraparesis in her 30s, whereas the mother of the proband presented with spastic paraparesis in her 40s, followed by symptoms of dementia in her mid 60s. The mutation was found only in the proband, and not in a normal family member, normal Japanese control subjects, patients with sporadic Alzheimer's disease or patients with familial spastic paraparesis without dementia. Thus, Y154N is a novel PSEN1 mutation responsible for FAD-SP of Japanese origin.  相似文献   
13.
We report a case of isolated unilateral absence of a pulmonary artery. The first clinical symptom that was manifested in the patient was recurrent hemoptysis, and subsequent angiography revealed that the main pulmonary artery was absent in the right lung, which was being fed only from the systemic circulation. Right pneumonectomy was performed, and neither the main pulmonary artery nor its remnant was detected in the resected right lung. Histologically, there were many muscular vessels in the resected lung, with intimal proliferation, or with plexiform-like lesions. The alveolar septum was moderately thickened and alveolar capillary vessels were dilated. We examined the alveolar capillary endothelial cells of the resected lung for immunoreactivity to thrombomodulin (TM) and von Willebrand factor (vWF). The endothelial cells were negative for TM and positive for vWF, while in the normal lung control group, these cells were positive for TM and negative for vWF. We considered that the hemodynamics of the systemic circulation in the resected lung caused the alteration of immunohistochemical characteristics in alveolar capillary endothelial cells.  相似文献   
14.
This study investigated the clinical characteristics of ciprofloxacin-resistant Proteus mirabilis isolates from urine samples associated with nosocomial infection or colonisation, and identified the risk-factors for ciprofloxacin resistance. Data for patients with ciprofloxacin-resistant P. mirabilis isolates (n=13) were compared with those for randomly selected patients with ciprofloxacin-susceptible P. mirabilis isolates (n=40) who were matched by temporal occurrence as control patients. The majority of ciprofloxacin-resistant P. mirabilis isolates were multiresistant, and ciprofloxacin resistance was associated significantly with previous use of fluoroquinolones and production of extended-spectrum beta-lactamases.  相似文献   
15.
Summary We have investigated the pharmacokinetics of the direct vasodilator flosequinan in elderly patients with congestive heart failure. Eight patients received a single dose of 50 mg, and 8 patients received once-daily treatment with 25 mg for two weeks.In the single dose study, the tmax of flosequinan was 2.5 h, Cmax was 1.17 g · ml–1 and t1/2 was 5.63 h. The tmax of the metabolite BTS 53554 was 20.3 h, Cmax was 1.44 g · ml–1 and t1/2 was 62.0 h.BTS 53554 accumulated gradually in the 14-day repeated dose study and steady-state was reached after approximately 2 weeks. Flosequinan was not found to accumulate.Adverse reactions were not observed in either the single or repeated dose study.It is advisable to consider renal function and body weight when flosequinan is to be administered to elderly patients with congestive heart failure. The initial dose should be 25 mg.  相似文献   
16.
Cyclins and cyclin-dependent kinases may reflect the status of cell proliferation in cancer tissues. The authors sought to determine whether cdc2 and cyclin D1 are expressed in breast cancer and are useful as prognostic factors. Accumulation of cdc2 and cyclin D1 proteins was examined in 88 cases of breast cancer using immunoblotting techniques and correlations with clinicopathological factors and prognoses were investigated. Cdc2 and cyclin D1 proteins were observed in 27.3% and 75.0% of breast cancers studied, respectively. The incidence of lymph node metastasis was significantly high in cdc2/cyclin D1-double positive group and low in double negative group. On the other hand, the incidence of estrogen receptor (ER) negative cases was significantly higher in the cdc2-positive/cyclin D1-negative group. Relapse-free survival times of cdc2-positive cases were significantly shorter than those of cdc2-negative cases. The relapse-free survival times of cyclin D1-positive cases also tended to be poorer than those of cyclin D1-negative cases. Multivariate analyses revealed cdc2 as the second most significant of the prognostic variables, following lymph node status. The three-year relapse-free survival rate of cdc2/cyclin D1-double positive cases was 58.9%, whereas that of cdc2/cyclin D1-double negative cases was 100%. Cdc2 and cyclin D1 represent the status of cell proliferation in breast cancer, and may be useful in breast cancer assessment.  相似文献   
17.
An 18-year-old male was admitted to our Emergency Department with a traumatic abdominal wall hernia (TAWH) of the left lower quadrant (LLQ) after suffering hypogastric blunt injury and urogenital lacerations in a motorcycle accident. Upright chest X-ray showed a small amount of right infradiaphragmatic free air, and a computed tomographic (CT) scan demonstrated an abdominal wall hernia. At surgery, no impairment was found in the digestive tract, and an abdominal herniorrhaphy was performed. It is suggested that the free air had passed through a connection between the scrotal laceration and the contralateral abdominal defect via the subcutaneous space and was palpated as emphysema. This is a new type of TAWH, which suggests that blunt abdominal trauma may result in negative pressure in the subcutaneous and peritoneal cavity, and this could reflect the pathophysiology of TAWH.  相似文献   
18.
目的 探讨正常双胎妊娠期间胎儿大脑中动脉搏动指数的变化;并与正常单胎进行比较.方法 采用彩色多普勒超声对34例正常双胎及176例正常单胎胎儿从孕23周至孕35周进行大脑中动脉搏动指数测定.结果 正常双胎胎儿大脑中动脉搏动指数随孕周呈逐渐下降趋势,与正常单胎胎儿比较,孕29周前该值为低,以后较之略高.结论 孕29周后双胎胎儿大脑中动脉血流阻力比单胎其值为高.  相似文献   
19.
20.
Aims/IntroductionGlucagon‐like peptide‐1 receptor agonists (GLP‐1 RA) might be less effective in patients with severe hyperglycemia, because hyperglycemia downregulated the GLP‐1 receptor in an animal study. To examine this hypothesis clinically, we compared the glucose‐lowering effects of GLP‐1 receptor agonist liraglutide with and without prior glycemic control.Materials and MethodsIn an open‐label, parallel trial, participants with poorly controlled type 2 diabetes were recruited and randomized to receive once‐daily insulin therapy, degludec (Insulin–GLP‐1 RA relay group, mean 16.8 ± 11.4 IU/day), for 12 weeks and then liraglutide for 12 weeks or subcutaneous injections of GLP‐1 RA, liraglutide (GLP‐1 RA first group, 0.9 mg), for 24 weeks. The primary efficacy end‐points consisted of changes in the levels of fasting plasma glucose and glycated hemoglobin (HbA1c).ResultsThe median fasting plasma glucose and HbA1c before the study were 210.0 mg/dL and 9.8%, respectively. The levels of fasting plasma glucose and HbA1c significantly decreased in the Insulin–GLP‐1 RA relay group (P < 0.001) and GLP‐1 RA first group (P < 0.001) by week 24, although no intergroup differences were observed. The reduction of HbA1c in the Insulin–GLP‐1 RA relay group tended to be larger than that in the GLP‐1 RA first group in the lowest CPR (C‐peptide immunoreactivity) quartile (P = 0.072). The adverse events consisted of gastrointestinal problems, followed by hypoglycemia.ConclusionsThe GLP‐1 receptor agonist is overall effective without prior glycemic control with insulin in participants with poorly controlled type 2 diabetes. However, in participants with insulinopenic type 2 diabetes, prior glycemic control with insulin might overcome glucose toxicity‐induced GLP‐1 resistance.  相似文献   
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