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神经生长因子对小鼠突触体内Ca^2+水平的调节作用 总被引:4,自引:1,他引:3
观察了多次海马内微注射NGF对小鼠突触体内游离钙水平的影响,并在离体情况下观察NGF对EGTA和CaCl2分别造成突触体内低钙和高钙状态的调节作用。结果如下:(1)在体实验表明,一定剂量的NGF可显著降低老年小鼠海马突触体内游离钙水平(P<005);(2)离体实验表明,当突触体游离钙水平降低时,适当剂量的NGF具有升高游离钙水平的作用;而突触体内游离钙水平升高时,则NGF有降低游离钙水平的作用。提示NGF对游离钙水平的双向调节作用可能是NGF改善老年性记忆衰退的作用机制。 相似文献
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Excimer laser coronary angioplasty is a new technique for ablation of coronary stenosis, however, the indications for its application are still controversial. We describe two male patients, 60 and 65 years old, who underwent unsuccessful balloon PTCA with a short, concentric and calcified coronary stenosis, although balloon inflation pressure was increased to a maximum in both cases. Excimer laser angioplasty following the failed procedures showed no evidence for tissue ablation angiographically, but a repeat attempt with balloon angioplasty was successful in both cases. Thus, laser angioplasty may be considered as an adjunct technique to balloon angioplasty after a failed PTCA in resistant, non-inflatable lesions. 相似文献
5.
Effect of body position on tongue posture in awake patients with obstructive sleep apnoea 总被引:2,自引:1,他引:1
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BACKGROUND: Snoring and obstructive sleep apnoea (OSA) are worse or may only occur in the supine position. The effect of body position on upper airway size has been reported, but the effect on tongue posture has not previously been examined. METHODS: Detailed measurements were made of tongue posture from upright and supine lateral cephalograms on 24 men with OSA and 13 men with non-apnoeic snoring matched for age, body mass index, and craniofacial skeletal pattern. Patients with OSA had apnoea/hypopnoea indices (AHI) of > 50/hour and/or apnoea indices (AI) of > 25/hour while non-apnoeic snorers had AHI of < 10/hour and AI of < 5/hour. RESULTS: In non-apnoeic snorers the tongue depth measurements for the superior-posterior portion of the tongue were larger in the supine than in the upright position (p < 0.05). There was no significant difference in tongue depth measurements between the upright and the supine position in the patients with OSA. CONCLUSIONS: When awake patients with OSA move from the upright to the supine position they maintain their upright tongue posture which may tend to protect against upper airway collapse secondary to the increased gravitational load on the tongue. In contrast, when awake non-apnoeic snorers move from the upright to the supine position a significant dorsal movement in the superior-posterior portion of the tongue is observed.
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Ali Gürbüz Bilgin Emrecan Levent Yilik Ibrahim Ozs?yler Mert Kestelli Cengiz Ozbek Nagihan Karahan 《European journal of cardio-thoracic surgery》2006,29(2):186-189
OBJECTIVE: The purpose of this study was to evaluate whether intracoronary shunt usage reduced the myocardial damage on the basis of the cardiac markers when compared with the shuntless anastomosis in off-pump coronary artery bypass grafting (OPCABG) surgery of isolated left anterior descending artery lesions. METHODS: Forty patients who had stable angina with isolated left anterior descending (LAD) coronary artery lesion undergoing OPCABG surgery were randomized into two groups. Shunt group consisted of 20 patients who had OPCABG using intracoronary shunt, whereas the shuntless group consisted of 20 patients who underwent OPCABG without using intracoronary shunt. Cardiac troponin I, CK, and CK-MB before and 24h after the surgery were assessed in the groups. RESULTS: There were no deaths in the study. The two groups were similar with respect to sex and age. Duration of LIMA-LAD anastomosis was significantly higher in the shunt group (p=0.01). There was no significant difference between the groups concerning the preoperative and postoperative CK and CK-MB levels. The preoperative troponin I levels of the groups were not different (p=0.238; NS), whereas postoperative levels of this marker was significantly higher in the shuntless group (p=0.003). CONCLUSION: Intracoronary shunt reduced the postoperative troponin I levels significantly, so it may be indicated in the patients who are thought to be susceptible to transient ischemia. 相似文献
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MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献
8.
Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
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