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71.
OBJECTIVES/HYPOTHESIS: Deterioration of aerodigestive tract reflexes such as the esophagoglottal and pharyngoglottal closure reflexes and pharyngeal swallow has been documented in the elderly. However, the effect of aging on the contractile response of the upper esophageal sphincter (UES) to pharyngeal water stimulation has not been studied. The aim of this study was to characterize the pharyngo-UES reflex in the healthy elderly. METHODS: We studied nine healthy elderly (77 +/- 1 y [SD]; four men, five women) and nine healthy young volunteers (26 +/- 2 y [SD]; four men, five women). AUES sleeve sensor was used to measure the pressure. We tested pharyngeal stimulation induced by rapid pulse and slow continuous injection of water. RESULTS: The volume of water required to stimulate the pharyngo-UES contractile reflex by rapid pulse injection in the elderly (0.5 +/- 34 0.1 mL) was significantly higher than that in the young (0.1 +/- 0.02 mL) (P < .05). In contrast to young subjects, there was no pressure increase in resting UES pressure observed in the elderly for continuous pharyngeal water infusion. In both young and elderly, the threshold volume for the pharyngo-UES contractile reflex was significantly lower than that for pharyngeal swallows. CONCLUSIONS: The pharyngo-UES contractile reflex deteriorates with aging. This deterioration is primarily due to abnormalities of the afferent limb of the reflex. 相似文献
72.
An overview of the upper esophageal sphincter 总被引:1,自引:0,他引:1
The anatomy and physiology of the upper esophageal sphincter (UES) are complex. Much progress has been made over the past
few years in our understanding this important sphincter. The closing muscles of the UES include the inferior pharyngeal sphincter,
the cricopharyngeus (CP), and the cervical esophagus. The CP is composed of two parts, which may have different functions.
The CP is innervated by the pharyngeal plexus and the recurrent laryngeal nerve. Tone of the UES is probably generated by
numerous reflexes rather than by specific tone-generating circuitry. The major tonegenerating muscle is the CP, which is highly
elastic and produces more active tension the more it is stretched. The UES opens by relaxation of the closing muscles, traction
by muscles attached to the hyoid bone and thyroid cartilage, and pulsion of the bolus. The various muscles of the UES behave
differently during its many dynamic states, so that similar functions are accomplished by different muscles. 相似文献
73.
Mohamed H. Shaker Halappa N. Konchigeri Albert H. Andrews Paul H. Holinger 《The Laryngoscope》1976,86(6):857-861
Fifty-one patients underwent 71 carbon dioxide laser procedures under general anesthesia for various intralaryngeal pathology. Anesthesia was induced with thiopental sodium followed by succinylcholine to facilitate endotracheal intubation. For maintenance of anesthesia, 70 percent nitrous oxide was supplemented with halothane, enflurane or small doses of fentanyl. Succinylcholine, d-tubocurare or pancuronium were used to maintain muscular relaxation of jaw, pharyngeal and laryngeal muscles for a smooth lasing procedure. Small diameter (16–22 Fr.), red rubber, cuffed endotracheal tubes provided maximum working space, facilitated the controlled ventilation and reduced the explosion hazard of the anesthetic gases. Safely eyeglasses were used by all the personnel in the operating room against accidental injury to the cornea by the laser beam. Anesthetic management provided excellent operative conditions with maximum safety to the patient and the personnel in the operating room. 相似文献
74.
The gut innervation is formed by an intrinsic and an extrinsic component. The former is responsible for the intestinal contractions that occur in the total absence of extrinsic innervation. We hypothesize that the intrinsic plexuses do not produce local contraction, but mediate reflex actions of the gut musculature. This hypothesis was investigated in the rectum of the experimental animal. In 16 anesthetized mongrel dogs, the rectum was exposed, and 3 monopolar silver-silver chloride electrodes were sutured serially to the rectal wall and connected to a rectilinear pen recorder. The rectal electric activity was recorded at rest and on rectal inflation while the anal pressure was synchronously registered. The tests were repeated after separate drug administration using phentolamine, propranolol (adrenoceptor blocking agents), atropine (cholinergic blocking agent), drotaverine (direct smooth muscle relaxant), and nitroglycerine. (NO donor, inhibitory noncholinergic, nonadrenergic mediator). Slow waves or pacesetter potentials (PPs) and action potentials (APs) were recorded from the three electrodes. Rectal balloon distension caused an increase of frequency, amplitude, and conduction velocity of these waves, as well as a decrease of anal pressure. Repetition of the test after administration of phentolamine, propranotol, and atropine effected no change in rectal electromyelographic (EMG) activity or anal pressure, while drotaverine and nitroglycerine administration aborted both the electric activity and the anal pressure response. We conclude that the rectal electric activity, presumably responsible for rectal motility, was not aborted by enteric nervous plexus block but by direct muscle relaxant. This suggests that the enteric plexus has no direct action on the rectal motile activity but mediates the rectal reflex actions. This concept might explain some of the hitherto unknown mechanisms of rectal dyssynergia syndromes. 相似文献
75.
Meckel’s diverticulum is a relatively common gastrointestinal entity which occasionally causes complications. Meckel’s diverticulum is classically described to mimic acute appendicitis when inflamed as well as being a cause of unexplained luminal gastrointestinal bleeding. An unusual cause of spontaneous non traumatic haemoperitoneum found during surgery performed for a suspected acute appendicitis in a 22-year old female is described. The patient was found to have a significant haemoperitoneum due to a bleeding serosal vessel of a Meckel’s diverticulum. The diverti-culum was routinely excised. It was macroscopically and histologically devoid of inflammation. The bleeding vessel was not found to be abnormal or part of an arteriovenous malformation. 相似文献
76.
Family history in patients with transient ischemic attacks 总被引:3,自引:0,他引:3
To determine the influence of family history on vascular disease, we surveyed hospital patients discharged with a diagnosis of transient ischemic attack. Of 117 respondents, 81 knew their family history for myocardial infarction and 81 knew their family history for stroke. Of 83 responding 43 reported a personal history of myocardial infarction, and of 85 responding 66 reported a personal history of stroke. As expected, there was an association between positive family and personal histories of myocardial infarction in younger (aged less than 70 years) patients (Fisher's two-tailed exact test, p = 0.014). This association was reversed for stroke (Fisher's two-tailed exact test, p = 0.017). Older (aged greater than or equal to 70 years) patients had a stronger association between positive family and personal histories of stroke; 14 (74%) of 19 older patients with a positive personal history of stroke had a positive family history of stroke. The reason for this reversal in the relation between family and personal histories of stroke compared with myocardial infarction may relate to the older age at onset of most strokes, differing stroke subtypes in older age groups, or lower rates of fatal myocardial infarction. This study suggests that familial factors may be important in some subtypes of cerebrovascular disease. Familial effects may be different in vascular diseases of the heart and brain. 相似文献
77.
Effect of praziquantel on certain immune responses of schistosomal egyptian patients 总被引:1,自引:0,他引:1
Z. A. Shaker H. I. Hassanein M. M. Kamel N. M. El-Bahairy A. H. El-Kalouby E. H. El-Raziky 《Parasitology research》1987,73(4):328-333
Specific antischistosomal IgG, IgM, and IgE were estimated by ELISA in 117 rural school students before specific treatment with praziquantel monthly for 3-4 months thereafter. IgG and IgM were estimated as percentage of bound antibodies. IgE was estimated by avidin-biotin ELISA (AB-ELISA) as IU/ml using a panel of known IgE standards. Soluble surface Schistosoma mansoni adult worm antigen was used for all estimates. Total IgE was estimated in a smaller group by an ELISA kit. The percentage of specific IgE was calculated. A group of endemic controls (22 students) and non-endemic controls (17 cases) were included. Statistical analysis of results showed the specific immunoglobulins to be significantly reduced 2 months after treatment of the schistosomal cases. These reduced levels, however, were still significantly higher than those of controls. The presence of early hepatosplenomegaly and the co-existence of other parasites had no significant influence on the results. No correlation could be established between the levels of specific antischistosomal IgG, M and E and the intensity of infection. The significance of these results is discussed. 相似文献
78.
79.
Given the strong genetic determinants of favorable HDL-C levels, the ability to procure the cardiovascular disease and longevity benefits associated with this mediator of the reverse cholesterol transport pathway through pharmaceutical intervention is challenging. Niacin is still the most robust HDL-C raising pharmaceutical agent on the market at its use leads to elevations up to 35%. Cholesteryl ester transfer protein (CETP) and endothelial lipase (EL) are two targets involved in the reverse cholesterol transport pathway that have become therapeutic targets of various investigations for raising HDL. However, the Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events (ILLUMINATE) trial was stopped in December 2006 due to excess mortality in the group of patients treated with torcetrapib, a CETP inhibitor. Other CETP inhibitors being studied include anacetrapib and JTT-705. Other CEPT inhibitors including TA-8995, DRL-17822, JTT-302, and others are under investigation. Additionally a biologic target CETi-1, an investigational vaccine in phase II development designed to elicit antibodies that bind and inhibit the activity of CETP leading to blocking the ability of the protein to transfer cholesterol from HDL to LDL and thus causing HDL cholesterol levels to rise is under clinical investigation for sometime. 相似文献
80.
This study is a search for the genetic susceptibility of Egyptians to Schistosoma haematobium infestation with its various bladder complications, including cancer. 80 bilharzial patients, 20 with simple bilharzial bladder cystitis, 30 with bilharzial bladder lesions, and 30 with bilharzial bladder cancer, as well as 35 normal Egyptian controls were studied. All patients were typed for HLA-A, B, C and DR antigens using the microlymphocytotoxicity test. HLA-A9 and its split Aw24 antigens were found to be negatively associated with the disease. As for the antigens with positive associations, HLA-B7 was significantly increased in the simple bilharzial cystitis group. In the bilharzial bladder cancer group, HLA-B16 and Cw2 antigens had positive associations. These findings might support the genetic control of the disease or the presence of an immune response and/or immune suppression genes which are in linkage disequilibrium with these HLA antigens and they control the susceptibility and pathological sequences of the disease. 相似文献