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1.
目的 探讨氨基甙类抗生素—阿贝卡星 (arbekacin ,ABK) ,阿司霉素 (astromicin ,ASTM) ,异帕咪星 (isepamicin ,ISP)和奈替咪星 (netilmicin ,NTL)在家兔的膈肌 ,前胫骨肌和比目鱼肌的神经肌肉抑制作用。方法 将 2 4只家兔平均分成 4组 ,戊巴比妥静脉麻醉下分别游离膈神经 -膈肌 ,胫神经 -前胫骨肌和腓总神经 -比目鱼肌 ,然后在膈肌表面和肢体肌远端肌腱固定连接肌张力换能测定装置以及在上述神经固定神经刺激电极 ,给予频率为 0 1Hz ,持续 0 1ms ,间隔 10s的超强电刺激。采用累积剂量给药法分别静脉注射以上被验 4种抗生素 ,记录刺激神经所诱发的肌肉等张颤搐强度 ,评价抗生素在 3种肌群不同神经肌肉抑制作用。结果  4种抗生素在以上 3种骨骼肌肌群均表现不同程度的抑制作用 ,在初期剂量给药时 ,膈肌对药物的敏感性较明显 ,比目鱼肌表现相对最弱。抗生素作用于这 3种肌群的ED50 值大小顺序为比目鱼肌 >前胫骨肌 >膈肌和ED95值大小顺序为比目鱼肌 >膈肌 >前胫骨肌。抗生素在前胫骨肌和比目鱼肌的ED50 值约分别为膈肌的 1 5和 2 7倍。 4种抗生素间神经肌肉抑制作用强度顺序为NTL >ABK >ASTM >ISP。这些抗生素引起的神经肌肉抑制作用可以被新斯的明和钙剂所拮抗。结论  4种氨基甙类抗生素在膈肌相  相似文献   
2.
Currently, molded helmet therapy is used to treat infants with deformational plagiocephaly. However, the indices of normal cranial shape remain unclear, and thus, the prevalence of deformational plagiocephaly is unknown, particularly in Japan. We investigated the reference values for cranial morphological characteristics in 1-month-old Japanese infants using a three-dimensional scanner, to determine the prevalence of deformational plagiocephaly. One hundred fifty-three healthy infants who visited three hospitals (from April 2020 to March 2021) were enrolled. Cranial shape was measured using a three-dimensional scanner and was analyzed using image analysis software. Outcome measures were cranial volume, length, width, length-width ratio, circumference, asymmetry, and vault asymmetry index; cephalic index; and anterior, posterior, and overall symmetry ratios. The cranial vault asymmetry index >3.5% or ≥10% were diagnosed as deformational or severe deformational plagiocephaly, respectively. The mean age at measurement was 35.7 days. The mean cranial volume was 559 mL; cranial length, 129 mm; cranial width, 110 mm; length-width ratio, 118%; cephalic index, 85.2%; cranial circumference, 377 mm, cranial asymmetry, 6.4 mm; cranial vault asymmetry index, 5.0%; and anterior, posterior, and overall asymmetry ratios, 93.1%, 91.3%, and 96.4%, respectively. The prevalence of deformational and severe deformational plagiocephaly was 64.7% and 6.6%, respectively. Sex-based differences were observed for cranial volume and width. The results obtained in this study can be considered standard values that can facilitate the differentiation of abnormal infant cranial morphological characteristics for Japanese medical practitioners.  相似文献   
3.
The purpose of this study was to evaluate the characteristicsof mitral annular motion during diastole in 28 normal subjects,40 patients with prior myocardial infarction (MI), and 23 patientswith coronary artery disease but without prior MI. Mitral annularmotion during diastole was obtained from the apex by M-modeechocardiography at the posterior wall of the left ventricle.Determinants of mitral annular excursion during early (MAE-E)and late diastole (MAE-L) were investigated in all subjects.Differences in the MAE-E, MAE-L, and the MAE-L.MAE-E ratio werecompared among the three patient groups. The Doppler-derivedtransmitral flow velocity-time integral during early (El) andlate (AI) diastole and mitral annular excursions during diastolewere obtained in 55 other patients with a prior MI and in 29healthy volunteers. The relationships between the MAE-L: MAE-Eratio and AI: EI ratio in these two groups were studied. The MAE-E was determined mainly by heart rate and left ventricularejection fraction (LVEF). The MAE-L was determined only by age.The magnitude of MAE-E was significantly less in patients witha prior MI than in normal subjects (P<0.01). However, theMAE-L did not differ among the three groups. The MAE-L.MAE-Ewas higher in patients with a prior MI than in normal subjects(P<0.05), and was significantly correlated with AI: EI inhealthy volunteers (r=0.65, P<0.001) and in patients witha prior MI (r=0.50, P<0.001). The MAE-E in patients with a prior MI decreases in proportionto the deterioration in LVEF. The relative at rial contributionto left ventricular longitudinal distension is increased inpatients with a prior MI and diastolic mitral annular motionhas a significant relationship to the transmitral flow. Thesefindings suggest that mitral annular motion during late diastoleplays an important role in maintaining left ventricular fillingin patients whose left ventricular systolic function has deteriorated.  相似文献   
4.
The clinicopathological features, the immunophenotype, and the presence of Epstein–Barr virus (EBV)-associated genomes and gene products were examined in 17 cases of CD30+ anaplastic large cell lymphoma (ALCL) of B-cell type. Microscopically, the 17 cases were divided into ten cases of the monomorphic type and seven cases of the pleomorphic type. EBV was detected in 6 of 17 cases (38 per cent) by RNA in situ hybridization (ISH) with EBV-encoded RNA (EBER1). EBER1+ cases consisted of two cases (20 per cent) of the monomorphic type and four cases (57 per cent) of the pleomorphic type. The five EBER1+ cases showed clonality of the EBV genome by Southern blotting, consistent with the presence of EBV in a monoclonal proliferation. The EBV-encoded latent membrane protein 1 (LMP1) was found in all six EBER1+ cases and EBV-encoded nuclear antigen 2 (EBNA2) was present in two cases by immunohistochemistry. No expression of LMP1 or EBNA2 was observed in the EBER1 cases. The EBER1+ cases had a tendency for a more favourable prognosis than the EBER1 cases. It is concluded that EBV has an association with CD30+ ALCL of B-cell type in the Japanese population studied, and especially with the large pleomorphic type. EBV infection may play a pathoaetiological role and may influence clinical behaviour.  相似文献   
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6.
Background and objective: Bronchiolitis obliterans (BO) has been reported to develop following ingestion of Sauropus androgynus (SA), a leafy shrub distributed in Southeast Asia. Little is known about direct effects of SA on airway resident cells or haematopoietic cells in vitro. Identification of the SA component responsible for the development of BO would be an important key to elucidate its mechanism. We sought to elucidate the direct effects of SA on airway resident cells or haematopoietic cells and identify the SA element responsible for the pathogenesis of BO. Methods: SA dry powder was partitioned into fractions by solvent extraction. Human and murine monocytic cells, epithelial cells and endothelial cells were cultured with SA solution or fractions eluted from SA. We also investigated the effect of SA in vivo using a murine BO syndrome (BOS) model. Results: The aqueous fraction of SA induced significant increases of inflammatory cytokine and chemokine production from monocytic lineage cells. This fraction also induced significant apoptosis of endothelial cells and enhanced intraluminal obstructive fibrosis in allogeneic trachea allograft in the murine BOS model. We found individual differences in tumour necrosis factor α (TNF‐α) production from monocytes of healthy controls stimulated by this aqueous fraction of SA, whereas it induced high‐level TNF‐α production from monocytes of patients with SA‐induced BO. Conclusions: These results suggest that an aqueous fraction of SA may be responsible for the pathogenesis of BO.  相似文献   
7.
SUMMARY.— Electron microscopic studies on embryonic hair development were performed using the scalp and eyebrow skin of 10 Negro embryos of the menstrual ages of 9 to 15 weeks. New ultramicroscopic findings were: (1) The peripheral cells of the hair germ extended into the mesenchyme pseudopodia, not covered by the basal lamina. (2) Mesenchymal cells crowded beneath the hair germ were connected with desmosome-like junctions. Direct contact of these cells with the basal lamina of the hair germ was seen. (3) A halfdesmosome- like structure was found between the mesenchymal cells and mesenchymal fine filaments.  相似文献   
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9.
Summary In this study we present a patient with the sublamina densa type of linear IgA bullous dermatosis (LABD). with IgA autoantibodies reactive with the 290-kDa type VII collagen (the epidermolysis bullosa acquisita (EBA) antigen) and with immunoblotting of normal human dermal extracts. The clinical and histological features of the present case were compatible with those of LABI) but quite different from those of RBA. Although EBA sera reacted with the bacterial fusion protein of the N-terminal globular (NC1) domain of type VII collagen, this patient's serum did not show reactivity. Furthermore, ultrastructural localization of target epitopes on the anchoring fibrils in this patient was considerably different from EBA. These results indicate that, whereas EBA antibodies react with the NC1 domain of type VII collagen, the epitope in this case is different from that of EBA (and is most likely on the central triple helical domain). This difference may be responsible for the clinical presentation in this patient being distinct from that of EBA.  相似文献   
10.
Xeroderma pigmentosum (XP) is an autosomal recessive disorder characterized by photo-induced deterioration of the skin, which often leads to the early development of skin cancers. To diagnose patients with XP and the related disorder Cockayne syndrome (CS), our laboratory has established a simple autoradiographic method that examines three cellular markers of DNA repair: unscheduled DNA synthesis (UDS), recovery of RNA synthesis (RRS) and recovery of replicative DNA synthesis (RDS). However, it is very laborious to measure the three markers using tritiated thymidine or uridine; therefore, we developed a non-isotope method for diagnosing XP and CS. Fibroblasts from the patient were labeled with bromodeoxyuridine (BrdU) instead of tritiated thymidine to measure UDS and RDS, or were labeled with bromouridine (BrU) instead of tritiated uridine to measure RRS. Incorporated BrdU or BrU could be detected using the immunofluorescence method. Moreover, we discovered a new useful marker for XP variant based on checkpoint activity. The non-radioisotope method and the new marker described here comprise an easy way to diagnose XP and CS.  相似文献   
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