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101.
Nitric oxide: a revolution of free radicals theory of aging 总被引:1,自引:1,他引:0
Q H Bin 《Medical hypotheses》1991,34(1):60-61
There are two kinds of free radicals in the aging process, 'bad' and 'good'. Nitric oxide is a good free radical. 相似文献
102.
Previous findings from this laboratory with the intracerebral microinjection technique suggested that the periaqueductal gray (PAG), nucleus accumbens, and habenula might constitute a unidirectional loop to play their roles in pain modulation. In the present study we demonstrate that intra-habenular injection of naloxone antagonizes the analgesia elicited by morphine injected into the periaqueductal gray (PAG) and that intra-accumbens injection of naloxone is capable of attenuating the analgesic effects of morphine injected into the habenula. These results indicate that the relationships between these nuclei may be more complex than the putative unidirectional loop. 相似文献
103.
For three years, we have performed craniotomy with a 5 cm diameter trephine through a linear incision. 53 craniotomies were done in 49 patients. This simple and time-saving method produced little bleeding and slight injury to the brain. The technique allowed the surgeon to spend most of his time at the management of lesion. Healing of wound was rapid and brain edema was minimal. 相似文献
104.
W R Jarnagin Q Y Duh S J Mulvihill J A Ridge T R Schrock L W Way 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(3):261-264
We analyzed 64 percutaneous endoscopic gastrostomy procedures performed by us between 1986 and 1990. Thirty patients had neurologic disease; 16 had head and neck cancers; eight had other malignancies; two had acquired immunodeficiency syndrome; and eight had other problems. Seven patients died within 30 days of complications (n = 4) or the primary illness (n = 3). Mean follow-up was 6 months; an additional patient died of aspiration and eight others died of their underlying illness. There were 19 complications (32%). Four wound complications occurred. Nine patients developed aspiration pneumonia within 3 days of the procedure, four of whom died in the hospital. Of the 24 patients with a history of aspiration, nine experienced aspiration during or after percutaneous endoscopic gastrostomy. Patients with a history of aspiration were more likely to have perioperative aspiration pneumonia, and patients who experienced aspiration were more likely to die. 相似文献
105.
Q. MALONE 《Journal of intellectual disability research : JIDR》1988,32(1):59-65
ABSTRACT. From 1976 to 1984, there were 149 Down's syndrome live births in Western Australia. Where previously the coexistence of congenital heart disease was a major determinant of early mortality, current survival rates do not reflect this. Survival rates have significantly increased over the last decade: particularly so for those with coexistent congenital heart disease. Projected frequencies for Down's syndrome persons in Western Australia are expected to significantly increase. This rise in prevalence will have major economic effects on the planning and delivery of health care for this population. 相似文献
106.
C H Kao S J Wang W Y Lin C Y Hsu S Q Liao S H Yeh 《Nuclear medicine communications》1992,13(10):764-766
This study, evaluating the effects of hyperthyroidism (HT) in oesophageal motility, depended on an oesophageal radionuclide transit test. A modified standard method was used to calculate: (a) total mean transit time (MTT), (b) residual fraction (RF) and (c) retrograde index (RI) in a supine position. Eighteen untreated patients with HT and 25 normal volunteers (NV) with a similar age distribution were included in this study. The results showed that oesophageal motility in patients with HT was worse than in the normal controls (P < 0.05 by Student's t-test). The correlation of MTT, RF and RI with size and function of thyroid glands in the patients with HT were calculated to explain the effects of HT in oesophageal motility. The results showed that neither the size nor the function of the thyroid glands in HT affected oesophageal motility. 相似文献
107.
108.
Cranial sonography provides a noninvasive, portable method for imaging the infant brain. This study describes the time-dependent, sonographic findings of infantile cerebral infarction, as well as computed tomographic (CT) scan and neuropathologic confirmation. Three hundred ninety-five infants under 18 months of age were sonogrammed over a period of 18 months. Three infants were diagnosed by cranial sonography and confirmed by CT scan and/or autopsy to have acute ischemic cerebral infarcts. The cases were followed with serial cranial sonograms for up to 18 months of age. The acute sonographic findings included a hyperechoic zone around the infarcted tissue. The subacute infarct had a checkerboard pattern, while the chronic infarcts were anechoic. 相似文献
109.
110.
Q. T. Dinh † D. A. Groneberg† C. Witt‡ C. Peiser† L. B. Cifuentes† N. Frossard§ B. F. Klapp A. Fischer† 《Clinical and experimental allergy》2004,34(12):1934-1941
BACKGROUND: The traditional neurotransmitter catecholamine and the neuropeptide tyrosine in sympathetic airway nerves have been proposed to be involved in the pathogenesis of airway diseases. OBJECTIVE: The aim of the present study was to investigate the effect of allergic airway inflammation on the expression of catecholamine enzyme tyrosine hydroxylase (TH), neuropeptide tyrosine (NPY) and tachykinins in mouse sympathetic airway ganglia. METHODS: Using neuronal tracing in combination with immunohistochemistry, the present study was designed to characterize TH, NPY and tachykinin profiles of superior cervical (SCG) and stellate ganglia after allergen challenge. RESULTS: The vast majority of fast blue-labelled SCG neurons (allergen: 97.5+/-1.22% (mean+/-SEM) vs. controls: 94.5+/-1.48%, P=0.18) and stellate neurons (allergen: 95.3+/-1.01% vs. controls: 93.6+/-1.33%, P=0.34) were immunoreactive for TH. Of the TH immunoreactive and fast blue-labelled SCG neurons, 52.0+/-1.01% allergen vs. 51.2+/-3.58% controls (P=0.83) and stellate neurons, 57.3%+/-0.97 allergen vs. 56.4+/-1.65% controls (P=0.64) were positive for TH only but not NPY, whereas 45.3+/-1.05% allergen vs. 43.3+/-1.18% controls (P=0.47) of fast blue-labelled SCG neurons and 37.9+/-0.86% allergen vs. 37.1+/-1.24% controls (P=0.62) of fast blue-labelled stellate neurons were immunoreactive for both TH and NPY immunoreactivities. There was a trend of an increase, but not significant one, in the percentage of TH-/NPY-immunoreactive and fast blue-labelled neurons in allergen-treated animals in comparison with the controls. Tachykinins, however, were not expressed by sympathetic neurons and were also not induced in sympathetic neurons after allergen challenge. CONCLUSION: The present study indicates that allergic airway inflammation does not alter the expression of noradrenalin and NPY in sympathetic ganglia and also shows that sympathetic neurons do not respond to allergic airway inflammation with tachykinins induction. However, a participation of catecholamine and NPY in the pathogenesis of allergic airway inflammation cannot be excluded in the present study as a higher neurotransmitter output per neuron following allergen challenge could be possible. 相似文献