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排序方式: 共有197条查询结果,搜索用时 328 毫秒
81.
Quadricuspid aortic valve (QAV) is a rare congenital heart valve disease, and more than half of QAV patients have severe aortic regurgitation (AR). We describe the case of a 66-year-old woman with QAV detected by transthoracic echocardiography during a medical checkup. Doppler echocardiographic examination showed mild aortic stenosis and mild AR. The patient has been under routine medical review without medication therapy. At follow-up echocardiographic examinations over a 4-year period, no significant changes in severity of aortic stenosis or AR were found. The clinical and functional characteristics of 192 cases of QAV were reviewed. The functional status of the QAV was known in 144 cases; of these, only 13 (9%) had both aortic stenosis and AR.  相似文献   
82.
We have previously reported the effect of hydrocortisone (HC) on the adenylate cyclase system of pig epidermis. HC had no effect on the basal level of cyclic AMP but there was an increased adrenalineinduced cyclic AMP accumulation when epidermal slices were incubated for more than 6 h with HC. This incubation did not alter the responsiveness to histamine. We are interested in the effects on epidermal cells of HC, which may act through the adenylate cyclase system. It is well documented that adrenaline, histamine and adenosine stimulate adenylate cyciase and cause an accumulation of cyclic AMP in pig epidermis. An increased cyclic AMP results in the inhibition of mitosis and epidermal outgrowth. Employing the rate of epidermal outgrowth and mitotic index as indicators of cyclic AMP effect, we studied the effect of HC on the adenylate cyclase system. The pretrcatment with HC (100 μM) magnified the inhibitory effect of adrenaline on epidermal outgrowth and mitosis, whereas the inhibitory effeet of histamine or adenosine was not affected by HC. It is suggested that HC induced an increased responsiveness of adenylate cyclase to adrenaline, resulting in a magnified inhibitory effect of adrenaline on epidermal outgrowth and mitosis.  相似文献   
83.
Using pig skin slices, we investigated the effects of hydrocortisone on the adenylate cyclase system of the skin. In short-term experiments, hydrocortisone, when added singly or in combination with other stimulators of adenylate cyclase in the skin (adrenaline or histamine), had no effect on cyclic AMP accumulation. However, when skin slices were incubated with hydrocortisone for more than 6 h, the response to adrenaline differed, with a greater accumulation of cyclic AMP in the hydrocortisone-treated skin. This effect was seen at a concentration of more than I micrometer hydrocortisone and was most marked 48 h later, while responses to adrenaline in control skin gradually decreased and remained low. Histamine, which is another stimulator of adenylate cyclase of the skin, did not cause a greater cyclic AMP accumulation in response to this hydrocortisone treatment. There was no significant difference in either low Km or high Km cyclic AMP phosphodiesterase activities as a result of this hydrocortisone treatment. Hydrocortisone seems to act by protecting the adrenaline-adenylate cyclase system of the skin.  相似文献   
84.
The present study was conducted to investigate whether non-fasting serum triglyceride (TG) levels can be used to assess a risk for the progression of carotid artery stenosis. This was a single- center retrospective study. Consecutive 96 patients with ≥50% stenosis of at least unilateral cervical internal carotid artery and normal fasting serum low-density lipoprotein cholesterol (LDL-C) levels of ≤140 mg/dL were followed up for at least 1 year (mean, 3.1 years), and clinical variables were compared between patients with and without carotid stenosis progression (≥10% increases in the degree on ultrasonography). Carotid stenosis progression was shown in 21 patients, associated with less frequent treatment with calcium channel blockers (CCBs), higher non-fasting TG and glucose levels. In carotid artery-based analyses including <50% stenosis side, stenosis progression was shown in 23 of 121 arteries except for those with complete occlusion and less than 1-year follow-up period because of carotid artery stenting (CAS) or carotid endarterectomy (CEA). Stenosis progression was more frequently observed in symptomatic and/or radiation-induced lesions, and was also accompanied with less frequent treatment with CCBs, higher non-fasting TG and glucose levels in carotid artery-based analyses. The receiver operating characteristic (ROC) curve analyses revealed that a cutoff value of non-fasting TG to discriminate carotid stenosis progression was 169.5 mg/dL for carotid arteries with the baseline stenosis of <50%, and 154.5mg/dL for those of ≥50%. Non-fasting TG level was an independent risk factor of carotid stenosis progression, and more strict control of non-fasting TG may be necessary for higher degree of carotid artery stenosis.  相似文献   
85.
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   
86.
87.
A disorder of the gracile axonal dystrophy (GAD) mutant mouse is characterized by a neuromuscular disease with sensory ataxia (detectable 30 days after birth) and paresis of the hindlimbs (detectable at 80 days). In the sensory ataxia stage, histological study of the primary sensory system shows that, in addition to the lesions in the central nervous system, peripherally projecting axons have also started to degenerate at their distal ends in muscle spindles. Although the structure of Ia fibre endings appear normal until 15 days after birth, initial changes in the annulo-spiral structure are detected around the 20th day by a degeneration of the terminal axons. Degeneration then progressed proximally and the secondary endings also start to degenerate. Neuron cell bodies located in the dorsal root ganglia are morphologically intact until the later stages. Chronological studies indicate that, although axonal degeneration progresses throughout life, it is accentuated during the rapid somatic growth period. Around 50 days of age, transient regeneration takes place at axonal endings when somatic growth has attained a plateau. Such primary sensory endings tend to be restored by fine, multiple axons which gain access to the intrafusal fibres through the original endoneurial tubes. Ultrastructural observations at the fully affected stage show intrafusal muscle fibres lying scattered within spindles due to loss of the fine network of inner capsule layers and an almost complete loss of sensory endings from the surface of intrafusal muscle fibres. These results indicate that this mutant mouse is a useful model for naturally occurring 'dying back' type axonal degeneration or 'central and peripheral distal axonopathies', and would provide significant information about the complete evolution of the pathological processes involved.  相似文献   
88.
Recently, the usefulness of the oblique transparent cylinder (OTC) in colonoscopy has been reported. In this study, the efficacy of two newly designed OTCs was evaluated. Colonoscopy performed by six experienced endoscopists in 1005 cases and by one inexperienced endoscopist in 177 cases was analyzed. Short (S) and ultra short (US) cylinders, shorter in length than a conventional long (L) cylinder, were used. The use of OTCs in colonoscopy contributed to a significantly faster insertion into the cecum. The average time to reach the cecum for experienced endoscopists were 12.4 ± 0.3 min without a cylinder, 9.0 ± 0.3 min with a US cylinder, 8.5 ± 0.4 min with an S cylinder and 6.9 ± 0.8 min with an L cylinder, respectively. The visual field and handling of the endoscope were more improved with the S cylinder than the conventional L cylinder. On the other hand, with the L cylinder, the success rate of one inexperienced endoscopist for total colonoscopy reached more than 90% and mean insertion time to reach the cecum was 16.4 ± 1.8 min 7‐months later. Both the success rate and average insertion time for the inexperienced endoscopist were satisfactory considering the rather short learning period. The OTCs were effective in reducing the insertion time. The use of the S cylinder overcame some of the disadvantages of the L cylinder; however, the L cylinder was helpful in improving the technique of an inexperienced endoscopist.  相似文献   
89.
目的:了解多潜能造血祖细胞向红系分化过程中造血因子受体的改变。方法;应用受体结合实验和Northern杂交技术分别测定了依赖Epo和GM-CSF增殖的造血相细胞株UT-7在Epo存在下向红系分化过程中Epo受体(EpoR)和GM-CSF受体(GM-CSF-R)及其mRNA的表达水平。结果;UT-7分化至红系阶段Epo-R表达明显上调,而高亲合力和中亲和力GM-CSF-R明显下调。结论:UT-7分化至红系阶段丧失对GM-CSF反应性是由于Epo促使GM-CSF-R-α和β亚单位表达下调所致。提示增加Epo-R和减少GM-CSF-R表达是Epo诱导髓系相细胞向红系分化的重要原因。  相似文献   
90.
In order to investigate the pathogenesis of acute gastric mucosal lesion after thermal injury, microcirculatory disturbance was assessed and observation of the behaviour of leucocytes was performed. Gastric blood flow decreased at 15 min post-thermal injury, and partially improved at 2 h; however, it decreased again at 5 h post-thermal injury. Mucosal microcirculatory disturbance was observed by using vascular labelling with monastral blue B. Deposits of monastral blue B were observed centring mainly on collecting venules but were also observed in the capillaries. Submucosal microcirculatory disturbance was observed through an intravital microscope. The irregularity of the wall and segmental constriction in the venules and presence of an arteriovenous shunting channel was observed in the submucosal layer at 5 h post-thermal injury. The percentage of rolling or sticking leucocytes that passed the confluence of a prevenule and a venule were significantly increased at 5 h after thermal injury. The present study revealed depression of gastric blood flow, mucosal and submucosal microcirculatory disturbance, and a significant increase of rolling and sticking leucocytes in the peripheral part of venules after thermal injury. Leucocyte-endothelial interactions may occur under such conditions and this interaction may play an important role in inducing the microcirculatory disturbance that results in an acute gastric mucosal lesion after thermal injury. The present study also demonstrated the possibility of intravital study of gastric submucosal arteriovenous shunting channels.  相似文献   
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