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101.
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Changes in immune function following surgery for esophageal carcinoma.   总被引:20,自引:0,他引:20  
Changes in immune function due to surgical injury have been well-documented. Immunosuppression is one of the causes of infectious complications leading to organ dysfunction in critical illness. It is not known what kind of surgery in the daily clinical practice causes immunosuppression. Stress response and immune function following surgery for esophageal carcinoma, assuming a highly-stressed operation, were studied and then compared with the stress response and immune function following gastric surgery, a moderately-stressed procedure. Forty patients who underwent esophagectomy and 39 patients receiving gastric operation were studied. The concentrations of serum interleukin-6 (IL-6) were measured preoperatively, at 1, 2, and 6 h, and at 1, 3, and 10 d after operation. Total protein, serum albumin, rapid turnover protein, serum CRP, and cortisol were measured before operation and at 1, 3, 7, and 21 d after operation. ConA- and PHA-stimulated lymphocyte proliferation, IgA, IgG, and IgM were also measured preoperatively, and on 7 and 21 d following surgery. The patients were fed exclusively by total parenteral nutrition (TPN). A striking rise of IL-6 was observed, with a peak in both groups at 1 to 6 h following operation. The peak values were 419+/-30 pg/mL, which was approximately twice as high in the esophagectomy patients as in the gastrectomy patients (195+/-40 pg/mL). CRP and cortisol also increased after operation, and these increases were also significantly greater in the esophagectomy patients. ConA- and PHA-stimulated lymphocyte proliferation decreased significantly 7 d after esophagectomy (P<0.05), but was unchanged in the patients receiving gastrectomy. Suppression of cellular immunity correlated significantly with serum cortisol, and was preceded by a rise in serum IL-6. The IgA, IgG, and IgM levels, however, remained unchanged from their preoperative values throughout the study in both groups. Nutritional status in terms of serum protein, albumin, and rapid turnover protein, decreased postoperatively, but there was no difference between the two groups. It is, therefore, concluded that cell-mediated immunosuppression, preceded by a hyperinflammatory response, is an observable reaction in patients following esophageal surgery, but not in patients undergoing gastric surgery.  相似文献   
103.
The site of impulse origin in the right atrium is generally considered to be a single static locus within the sinoatrial (SA) node. However, it has been recognized that the pacemaker site may shift as a consequence of changes in physiological and pathological conditions. To determine the role of the atrial pacemaker complex including the superior pacemaker site, SA node and inferior pacemaker site quantitatively, we investigated atrial rate and the earliest activation region (EAR) from the isochronal activation sequence map by 48 unipolar electrodes and the mapping system. The epicardial activation sequence of the right atrium including the SA node region was obtained from the 48 electrodes, which were fixed to two flexible templates made of soft plastic plates. Using the mapping system, we found that (1) the EAR was shifted by the sympathetic or parasympathetic neural activity, (2) parasympathetic activity predominates over the sympathetic activity not only on heart rate, but also on the location of the EAR, and (3) the role of the inward Ca2+ current, hyperpolarization inward current and delayed rectifier K+ current, of the pacemaker cells distributed in the atrial pacemaker complex is different in the dog heart in situ.  相似文献   
104.
Non-P-glycoprotein-mediated multidrug-resistant C-A120 cells that overexpressed multidrug resistance protein (MRP) were 10.8- and 29. 6-fold more resistant to 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin (CPT-11) and SN-38, respectively, than parental KB-3-1 cells. To see whether MRP is involved in CPT-11 and SN-38 resistance, MRP cDNA was transfected into KB-3-1 cells. The transfectant, KB/MRP, which overexpressed MRP, was resistant to both CPT-11 and SN-38. 2-[4-Diphenylmethyl)-1-piperazinyl]ethyl-5-(trans-4,6-dimethyl-1,3 , 2-dioxaphosphorinan-2-yl)-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate P-oxide (PAK-104P) and MK571, which reversed drug resistance in MRP overexpressing multidrug-resistant cells, significantly increased the sensitivity of C-A120 and KB/MRP cells, but not of KB-3-1 cells, to CPT-11 and SN-38. The accumulation of both CPT-11 and SN-38 in C-A120 and KB/MRP cells was lower than that in KB-3-1 cells. The treatment with 10 microM PAK-104P increased the accumulation of CPT-11 and SN-38 in C-A120 and KB/MRP cells to a level similar to that found in KB-3-1 cells. The ATP-dependent efflux of CPT-11 and SN-38 from C-A120 and KB/MRP cells was inhibited by PAK-104P. DNA topoisomerase I expression, activity, and sensitivity to SN-38 were similar in the three cell lines. Furthermore, the conversion of CPT-11 to SN-38 in KB-3-1 and C-A120 cell lines was similar. These findings suggest that MRP transports CPT-11 and SN-38 and is involved in resistance to CPT-11 and SN-38 and that PAK-104P reverses the resistance to CPT-11 and SN-38 in tumors that overexpress MRP.  相似文献   
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We reviewed the clinical records of 15 patients with parosmia examined in our department from April 1987 to September 1990. Seven (29.2%) of 24 patients with olfactory disturbance caused by traumatic injury complained of parosmia. Eight (23.2%) of 34 patients with olfactory disturbance caused by influenza also showed parosmia. The incidence of parosmia between two groups was not statistically significant (p greater than 0.05). Parosmia was observed in none of 42 patients with olfactory disturbance caused by nasal-paranasal diseases. All patients (n:15) always perceived odors as unpleasent. Twelve of them had spontaneous parosmia, and three patients recognized the unpleasant smell when an odor came. In comparison with the auditory system, we speculated that spontaneous parosmia resembles tinnitus. The cause of tinnitus is recognized as a disturbance of the auditory nerve (the first order neuron). Tinnitus is rare in patients with conductive hearing loss, and cases of olfactory disturbance of the "respiratory dysosmia" did not complain of parosmia. Post-traumatic olfactory disturbance is caused by transection of the fila olfactoria, which is part of an olfactory neuron, while post-inflammatory olfactory disturbance is caused by damage to olfactory receptor cells. Furthermore, the fact that the incidence of parosmia between the two groups was not statistically significant suggests the same etiological mechanism in receptor cells. We consider that parosmia is caused by damage to olfactory sensory neurons.  相似文献   
108.
Selective neuronal death in the CA1 sector of the hippocampus [delayed neuronal death (DND)] develops several days after transient global cerebral ischemia in rodents. Because NGF plays a potential role in neuronal survival, it was decided to study its effect in DND. We report here that intraventricular injection of NGF either before or after 5 min forebrain ischemia in the Mongolian gerbil significantly reduced the occurrence of DND. The tissue content of NGF in the hippocampus was decreased 2 d after ischemia and recovered to the preischemic level by 1 week. By the Golgi staining technique, changes first began in the dendrites of affected neurons as early as 3 hr. Such changes could be ameliorated by NGF treatment. Although previous knowledge of NGF is limited to the survival of cholinergic neurons in the CNS, it is assumed that other mechanisms must be operating in the hippocampus, for example, postsynaptic modification at dendrites or aberrant expression of NGF receptors possibly at the initial excitation period by glutamate. Furthermore, because previous work has shown that inhibition of protein synthesis reduces the occurrence of DND, a program leading to cell death might also be operating via de novo synthesis of certain protein(s), collectively termed "killer protein," because of a lack of NGF.  相似文献   
109.
BACKGROUND: Ketotic hypoglycemia is the most common cause of recurrent hypoglycemia in early childhood but its etiology is poorly understood. Elimination diets have been used for the prevention or treatment of some allergic diseases; however, these diets entail a risk to the normal nutrition and growth of children. The present study investigated whether elimination diets are related to the occurrence of ketotic hypoglycemia. METHODS: The prevalence of allergy treated with elimination diet therapy was retrospectively investigated in 18 patients with ketotic hypoglycemia seen in Yamaguchi University Hospital between January 1995 and September 1999. Data were gathered by reviewing the patients' medical charts. RESULTS: Ten (55.6%) of 18 patients with ketotic hypoglycemia had allergic diseases. Six (60%) of the patients had been treated with strict elimination diets and the others were on incomplete elimination diets for the prevention of allergy. The ketotic hypoglycemia patients with allergic diseases had experienced fewer pre-existing infectious diseases than those without allergic diseases. CONCLUSIONS: Patients with allergic diseases treated with elimination diets have a relatively high tendency towards developing ketotic hypoglycemia. They might have a lower capacity to tolerate fasting due to their excessive avoidance of many foods, even during periods when they are not undergoing strict elimination diets.  相似文献   
110.
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