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11.
Nerve growth factor (NGF) gene expression in central nervous system (CNS) glia appears to be associated with active glial growth. To study the underlying molecular mechanisms, we examined the effects of a number of growth-related factors on NGF mRNA expression in glial cultures. Our results suggest that glial membrane interaction, as a consequence of growth, actively inhibits NGF gene expression in CNS glia.  相似文献   
12.
Adrenergic signalling between rat taste receptor cells   总被引:2,自引:0,他引:2  
In taste buds, synaptic transmission is traditionally thought to occur from taste receptor cells to the afferent nerve. This communication reports the novel observation that taste receptor cells respond to adrenergic stimulation. Noradrenaline application inhibited outward potassium currents in a dose-dependent manner. This inhibition was mimicked by the β agonist isoproterenol and blocked by the β antagonist propranolol. The α agonists clonidine and phenylephrine both inhibited the potassium currents and elevated intracellular calcium levels. Inwardly rectifying potassium currents were unaffected by adrenergic stimulation. Experiments using the RT-PCR technique demonstrate that lingual epithelium expresses multiple α (α1a, α1b, α1c, α1d, α2a, α2b, α2c) and β (β1, β2) subtypes of adrenergic receptors, and immunocytochemistry localized noradrenaline to a subset of taste receptor cells. Collectively, these data imply strongly that adrenergic transmission within the taste bud may play a paracrine role in taste physiology.  相似文献   
13.
From 1955 to 1984, radical neck dissection (RND) had been done in 300 salivary carcinoma patients, 114 of which had regional lymph node metastasis, with a 38% metastatic rate. Respective 3, 5, 10, 15, 20 year survival rates were 76, 64, 47, 35, 35% in a 3 to 20 years follow-up study in 283 patients (94.33%). The following four points are concluded: 1. The metastatic rate is determined not only on tumor staging, but more to its typing (pathologic behaviour). 2. Elective RND gave a better prognosis than therapeutic and negative metastasis has a better survival chance than positive where the low level metastasis is the worst. 3. According to pathologic typing, Elective RND is indicated for undifferentiated adenocarcinoma, high malignant mucoepidermoid carcinoma, squamous cell carcinoma, adenocarcinoma and papillary cystic adenocarcinoma, therapeutic RND for malignant pleomorphic adenoma, acinic cell carcinoma and mucoepidermoid carcinoma. 4. Unilateral RND is indicated for all but sublingual and buccal tumors.  相似文献   
14.
我在20世纪80年代初期,曾发表“北方亦多湿论”的短文,但失之过简,今按四时更迭,主要节令交替详细阐述之。在未入正题之前,先读一下毛主席的《沁园春·雪》,俾对北方气候有所了解:“北国风光,千里冰封,万里雪飘,望长城内外,惟余莽莽,大河上下,顿失滔滔。山舞银蛇,原驰蜡象,欲与  相似文献   
15.
BACKGROUND AND PURPOSE: The catastrophic Chi-Chi earthquake of September 21, 1999 in Taiwan provided a unique opportunity to study the disaster's psychiatric impact on survivors. This study assessed the development of psychiatric disorders among residents in a Taiwanese village near the epicenter of the earthquake within 6 months of the disaster. METHODS: A total of 442 of the 602 actual living residents of Tong-Chi village who were over 16 years of age and were present in the community at the time of the earthquake were included in this population survey. Subjects were interviewed by psychiatrists using the Mini-International Neuropsychiatric Interview and questionnaires to collect demographic information and risk factors for psychiatric disorders 4 to 6 months after the earthquake. RESULTS: The prevalence rates were 9.5% for current major depression, 2.8% for past major depressive episode, and 7.9% for post-traumatic stress disorder (PTSD). Females had significantly higher rates of most psychiatric disorders. After controlling for covariates, the significant risk factors for PTSD were female gender and having sought medical service after the earthquake. Significant risk factors for major depressive episode were divorced/widowed status, education level equal to or below primary school, and prominent house damage. CONCLUSION: This population survey of earthquake disaster survivors found an increased prevalence of psychiatric disorders after exposure to a catastrophic earthquake. These results highlight the need for prompt therapeutic attention to residents of earthquake disaster areas after the event.  相似文献   
16.
While balloon valvuloplasty has been widely used for the treatment of congenital valvular pulmonary stenosis (PS) in children and adults, its use in elderly patients is less common. An 80-year-old woman with congenital valvular PS received valvuloplasty with double-balloon technique. Right ventricle systolic pressure and pulmonary valve systolic pressure gradient decreased from 95 to 44 mm Hg and from 75 to 35 mm Hg, respectively. Follow-up Doppler echocardiography 2 months later showed further decrease in the transvalvular systolic pressure gradient to 29 mm Hg. The patient had symptomatic relief, and no major complication was noted. Balloon pulmonary valvuloplasty can be an effective treatment for elderly patients with congenital valvular PS.  相似文献   
17.
X-linked hyper-immunoglobulin M (IgM) syndrome (XHIGM) is a rare genetic primary immunodeficiency disease caused by mutations of the CD40 ligand (CD40L) gene with normal or elevated levels of IgM and markedly decreased serum IgG, IgA, and IgE. Liver disease may occur as a clinical manifestation in XHIGM. This complication appears to increase with age. We report an 18-year-old male patient who had recurrent episodes of acalculous cholecystitis (AC) and sclerosing cholangitis (SC). The diagnosis of XHIGM was confirmed by the finding of CD40L expression < 1% of normal and a tyrosine 169 asparaginase (t526a) mutation in exon 5 (the tumor necrosis factor domain) of the CD40L gene. The patient had direct hyperbilirubinemia (direct bilirubin 5.5 mg/dL, total bilirubin 8.7 mg/dL), cholestasis (alkaline phosphatase 1133 U/L, gamma-glutamyl transferase 1019 U/L) and elevated transaminases (aspartate aminotransferase 70 U/L, alanine aminotransferase 101 U/L). Findings on abdominal ultrasound and abdominal computed tomography were compatible with AC. After the fourth episode of cholecystitis, cholecystectomy and liver biopsy were performed. Operative cholangiography revealed poor opacification of the hepatic duct and proximal common bile duct; the upstream intrahepatic bile ducts were not visualized. The biopsy specimen showed marked fibrosis of the portal areas. Enterococcus species was cultured from the bile. Children or adolescents with recurrent AC and SC should be evaluated for an underlying immunodeficiency syndrome such as XHIGM.  相似文献   
18.
BACKGROUND AND PURPOSE: This report describes the results of matched-unrelated-donor transplant for leukemia or myelodysplasia in the first 23 recipient children at a single medical center in Taiwan. METHODS: Between August 1994 and February 2003, 23 consecutive children with leukemia or myelodysplasia underwent matched-unrelated-donor bone marrow transplantation (BMT). The preparative regimen consisted of fractionated total body irradiation and cyclophosphamide in 6 patients; busulfan in combination with etoposide and cyclophosphamide in 4 patients who received cranial irradiation before transplantation; and busulfan and cyclophosphamide in 13 patients. RESULTS: Engraftment was achieved in 91.3% of cases. Acute graft-versus-host disease (GVHD) occurred in 18 of 21 patients who engrafted (85.7%). Event-free survival for all patients was 24.46 +/- 9.24%. The 12 children with standard-risk disease had better event-free survival than the 11 children with high-risk disease (46.88 +/- 15.03% vs 0%, p < or = 0.001). CONCLUSIONS: The major obstacles to successful matched-unrelated-donor BMT are acute GVHD, relapse and infection. Early transplantation and patient selection, prophylactic and therapeutic maneuvers for GVHD, as well as appropriate donor selection and virus prophylaxis may improve the results.  相似文献   
19.
Pneumocephalus is a very rare complication of video-assisted thoracoscopic surgery (VATS). A 66-year-old man developed pneumocephalus secondary to thoracoscopic excision of a neurogenic tumor in the posterior mediastinum. Pneumocephalus was diagnosed by brain computed tomography. Neurosurgical intervention was performed after conservative therapy had failed. The patient's condition had resolved without any neurologic sequelae 2 years later. When a patient has a relatively large amount of chest tube drainage and neurologic symptoms after VATS, the possibility of pneumocephalus due to cerebrospinal fluid leakage must be considered.  相似文献   
20.
INTRODUCTION: Ischemic heart disease is a major cause of heart failure in western societies. However, the factors that may influence left ventricular function (LVF) recovery after an acute coronary syndrome (ACS) are still unclear. OBJECTIVE: To identify variables that may influence LVF evolution one year after ACS. METHODS: 104 patients hospitalized with ACS between 7/1/2001 and 12/31/2002 and with systolic dysfunction--defined as an echocardiographic ejection fraction (EF) < or = 45%--were randomly allocated to a planned coronary follow-up program (FUP) or a general cardiology clinic (GC); patients from both groups were also randomly referred to a structured cardiac rehabilitation program (CRP). EF was re-assessed at one year. We compared differences between patients who recovered left ventricular function (EF > 45%; group 1) and those who did not (group 2). RESULTS: One year after discharge, 44.2% of the patients had recovered function. There were no significant differences between the groups in gender (77.7 vs. 76.5% male), age (56 vs. 59 years), hypertension, diabetes, dyslipidemia, smoking habits or family history. A previous history of cardiovascular events was more frequent in group 2 (11.1% vs. 35.3%, p = 0.03). Cardiac catheterization was performed before discharge in 88.8% and 88.2% in groups 1 and 2 respectively (p = NS); no differences were found in coronary anatomy between the two groups. Angioplasty was performed in 54.2% in group 1 and 50% in group 2 (p = NS). There were no differences in the use of angiotensin-converting enzyme inhibitors (83.3% vs. 87.5%), beta-blockers (87.5% vs. 87.5%), nitrates (37.5% vs. 33.3%), aspirin (95.8% vs. 95.8%), statins (79.1% vs. 75%) or diuretics (20.8% vs. 45.8%). There was no significant difference in LVF recovery between patients randomized to FUP or GC (38.5% vs. 54.5%). 87.5% of patients who completed the CRP had normal EF at one year compared to 32.7% of patients not referred to the program (p = 0.009). Although EF improved in both groups, this improvement was greater in patients who completed a CRP (EF 8% vs. 5%, p = 0.003). CONCLUSION: A previous cardiovascular event and completion of a CRP were the only variables that influenced LVF recovery. Thus, enrollment in a CRP, in addition to standard therapy, could be an important therapeutic measure in patients with systolic dysfunction after ACS; our data suggest that these programs should be more widely used.  相似文献   
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