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41.
Splanchnic ischaemia and its role in multiple organ failure   总被引:3,自引:0,他引:3  
Multiple organ failure remains the leading cause of death in the intensive care unit. Increasing numbers of investigators have focused their attention on the role of gastrointestinal tract in the pathogenesis of this syndrome. Their data indicate that inadequate gut perfusion leads to a measurable imbalance between oxygen delivery and the needs of the tissues, i.e., ischaemia. Gut ischaemia of sufficient duration impairs gastrointestinal tract barrier function, facilitating the passage of enteric bacterial endotoxin into the circulation. It has been hypothesized that production of tumor necrosis factor α, and other biologic mediators by endotoxin–stimulated macrophages, triggers a generalized and uncontrolled inflammatory response that ultimately leads to multiple organ failure.
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed.  相似文献   
42.
本文应用HRP顺、逆行追踪法结合免疫细胞化学双重标记法,对大鼠孤束核向伏核的投射进行了研究。主要结果如下:1.WGA-HRP注入孤束核尾侧段,在伏核后部的腹、内侧区,出现较密集的标记纤维、终末和标记细胞;将HRP注入伏核后部的腹、内侧区,在孤束核尾侧段(主要在连合核和内侧亚核)出现大量的顺、逆行标记,以同侧为主。2.HRP注射到伏核并结合免疫细胞化学反应,在孤束核尾侧段发现HRP-TH,HRP-NT、HRP-CCK双重标记细胞。HRP-TH的数目最多,其次是HRP-NT双标细胞,HRP-CCK双标细胞最少。  相似文献   
43.
Our objective was to determine the extent to which lower urinary tract symptoms affect the general health status of men and contribute to the decision to undergo surgery. A cross-sectional population survey using postal questionnaires was conducted in the North West Thames health region, followed by a prospective cohort study of men undergoing prostatectomy (North West Thames and Oxford regions). The subjects in the first survey were 221 men aged 55 and over with previously reported mild, moderate or severe urinary symptoms; subjects in the second study were 388 men undergoing prostatectomy. Main outcome measures were selfreported symptom severity, bothersomeness and general health status (Nottingham Health Profilie, Part 1). The response rate among eligible responders in the population survey was 85.7%. Increasing symptom severity was associated with worsening NHP scores for energy, emotional reactions, sleep and physical mobility (p<0.01). Increasing bother-someness of symptoms was associated with emotional reactions, sleep and pain (p<0.05). Men undergoing surgery reported worse health status than men in the population with the same severity of symptoms as regards emotional reactions, energy and pain. For a given level of symptom severity, the impact of those symptoms on aspects of a man's general health status may be the determinant of seeking and undergoing surgery. Greater understanding of the factors that affect a man's response to his symptoms is needed in interpreting the decision to seek and accept treatment.  相似文献   
44.
This study compares the efficacy of omeprazole and ranitidine at reducing gastric secretion in obstetric patients. Sixty-five women scheduled to undergo elective Caesarean section under general anaesthesia were randomly allocated to receive either omeprazole 40 mg or ranitidine 150 mg orally at 2200 hours the night before and at 0600 hours on the morning of surgery. Intragastric pH and volume were measured immediately after induction of anaesthesia and on completion of surgery. All patients had gastric aspirates less than 25 ml. None of the omeprazole group had an aspirate of pH less than 3.5. Six patients (19%) in the ranitidine group had aspirates of pH less than 3.5, a significant difference from the omeprazole group (p less than 0.05). Of these six, two (6%) had aspirates of pH less than 2.5. Hence this study showed that omeprazole was more effective and consistent than ranitidine at maintaining gastric pH greater than 3.5.  相似文献   
45.
46.
In order to examine the effect of growth hormone on urinary pyridinoline excretion, 32 patients with complete or partial growth hormone deficiency had their urinary pyridinoline excretion measured while receiving growth hormone and for 14 days after it was discontinued. There was a significant positive correlation between increases in growth velocities during the first year of growth hormone administration compared to before it, and the ratio of the urinary pyridinoline excretion levels while receiving growth hormone to those after discontinuation. Therefore, urinary pyridinoline excretion rapidly decreased in patients with growth hormone deficiency when the administration of growth hormone was stopped. Exogenous growth hormone appears to stimulate bone resorption in these patients.  相似文献   
47.
AIM: The aim of the present study was to investigate the safety and efficacy of endoscopic laser therapy for transitional cell carcinoma (TCC) of the upper urinary tract. METHODS: Tumors of the renal pelvis and ureteropelvic junction were detected by ureteroscopy. The tumors were subjected to biopsy, and after TCC was diagnosed, endoscopic laser therapy (Neodymium-YAG and Holmium-YAG) was conducted using a 6.9 Fr. flexible ureterorenoscope. RESULTS: From January 1997 to April 2002, six patients underwent ureteroscopic treatment. Tumor grade was 1 in four patients and 2 in two patients. Average tumor size was 1.45 cm. Endoscopic treatment was chosen for two patients because of the high medical risk associated with open surgery. Another patient underwent diagnostic ureteroscopy, followed immediately by endoscopic treatment. A further three patients elected to undergo ureteroscopic treatment. One patient with large (3 cm), multifocal and incompletely treated tumors died of metastatic disease 22 months after the initial operation. One patient requested nephroureterectomy one month after endoscopic treatment, and pathological examination of the resected specimen revealed no tumor. The other four patients have been followed up for a mean period of 14 months after initial treatment. Recurrence occurred in one patient, and was successfully treated by repeat endoscopic resection. None of the patients required blood transfusion or emergency open surgery. CONCLUSION: Ureteroscopic treatment of small, localized, low-grade TCC of the upper urinary tract is now a safe and feasible alternative to nephroureterectomy in selected patients.  相似文献   
48.
Stimulation of the nasal mucosa produces a number of respiratory reflexes the afferent limb of which is provided by the ethmoidal nerve, a branch of the trigeminal nerve. In the cat this nerve terminates within the trigeminal nucleus. It has no direct projection to brainstem respiratory centres. This study examines the response of respiratory-related neurones in the nucleus of the solitary tract (NTS) to ethmoidal stimulation. It demonstrates that these neurones show both excitatory and inhibitory responses to ethmoidal stimulation. Thus, the NTS appears to be involved in respiratory reflexes initiated by stimulation of the nasal mucosa.  相似文献   
49.
The "transmitter-specific" retrograde axonal tracer 3H-D-aspartate has been used to demonstrate neurons in the olfactory bulb which putatively utilize aspartate and/or glutamate as their neurotransmitter and which send an axon either to the piriform cortex or within the bulb itself. Injections of 3H-D-aspartate into layer I of the anterior piriform cortex, in the zone of termination of axons from the olfactory bulb, labeled only a few cells in the main olfactory bulb, located in the mitral and external plexiform layers. Although these cells resembled mitral and tufted cells, they tended to have smaller somata than other mitral or tufted cells and apparently form a distinct subpopulation of relay cells. In contrast, many of the mitral cells of the accessory olfactory bulb were labeled by the same injections of 3H-D-aspartate, probably as a result of involvement of the accessory olfactory tract or its bed nucleus in the injection site. Similar injections of the "nonspecific" tracer HRP into the anterior piriform cortex labeled most of the cells in the mitral cell layer of both the main and accessory olfactory bulbs, and some tufted cells in the external plexiform layer. It is concluded that only a small, distinct subpopulation of the mitral or tufted cells of the main olfactory bulb are aspartatergic and/or glutamatergic, while many (at least) of the mitral cells of the accessory olfactory bulb use the excitatory amino acids as transmitters. Injections of 3H-D-aspartate directly into the main olfactory bulb also failed to label the mitral and deeply situated tufted cells. However, a few cells were labeled in the periglomerular region, the superficial external plexiform layer, and the granule cell layer near the injection site. These labeled cells were smaller than mitral and tufted cells but generally larger than periglomerular or granule cells. They may represent a population of glutamatergic or aspartatergic short axon cells. In addition, small cells of an unknown type were labeled in the olfactory nerve layer following injections in the deepest part of the bulb. These cells do not correspond to any of the well characterized cell types of the olfactory bulb.  相似文献   
50.
Summary The site of omeprazole inhibition of adrenal steroidogenesis has been sought in vivo by analyzing the patterns of urinary steroid metabolite excretion after 6 days of treatment with placebo/omeprazole.Excretion rates of androsterone, aetiocholanolone, dehydroepiandrosterone, 11 hydroxyandrosterone, tetrahydrocortisone, tetrahydrocortisol and cortolone were reduced, indicating a block at an early step in steroidogenesis, possibly cholesterol side-chain cleavage. In vitro studies have confirmed this finding by measuring conversion of added precursors to cortisol in isolated bovine adrenocortical cells. Cortisol synthesis from added 20 hydroxycholesterol was inhibited by 83% in the presence of 100 µg omeprazole/ml. Conversion from pregnenolone and progesterone and their 17 hydroxylated derivatives was inhibited by 20–40% whereas cortisol production from added 11 deoxycortisol was not affected.These data suggest that omeprazole primarily inhibits cholesterol cleavage and does not inhibit 3 hydroxysteroid dehydrogenase, 17 hydroxylase or 11 hydroxylation; 21 hydroxylase activity may be marginally attenuated.  相似文献   
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