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991.
The relationship between nm23 expression, HPA staining, and other clinicopathological variables, i.e., axillary (AX) and internal mammary lymph node (IMN) metastases was assessed, and their prognostic values were analyzed. Positive HPA staining was found to be significantly correlated with tumor size, and with AX and IMN metastases, whereas negative nm23 expression was significantly correlated with AX and IMN metastases. A univariate study revealed that overall survival was correlated significantly with tumor size, AX and IMN metastases, and HPA staining, whereas nm23 expression did not appear to be a significant prognostic factor. In a multivariate study, only AX and IMN metastases were significant prognostic factors. When AX and IMN metastases were excluded from the Cox model, however, only HPA staining had independent prognostic value for survival. In this study, therefore, it may be concluded that HPA staining was more closely correlated with AX and IMN metastases, and with survival than nm23 expression.  相似文献   
992.
The Pax-1 gene has been found to play an important role in the development of the vertebral column. The cervico-occipital transitional zone is a specialized region of the vertebral column, and malformations of this region have frequently been described in humans. The exact embryonic border between head and trunk is a matter of controversy. In order to determine a possible role of Pax-1 in the development of the cervico-occipital transitional zone we studied the expression of this gene in a series of quail embryos and murine fetuses with in situ hybridization and immunohistochemistry. Pax-1 is expressed in all somites of the embryo, including the first five occipital ones. During embryonic days 3–5 the gene is down-regulated in the caudal direction within the first five somites, whereas more caudally Pax-1 is strongly expressed in the cells of the perinotochordal tube. In 5-day-old quail embryos, the cartilaginous anlage of the basioccipital bone has developed and there is no more expression of Pax-1 in this region. The fusion of the dens axis with the body of the axis also coincides with switching off of the Pax-1 gene. More caudally, the gene is continuously expressed in the intervertebral discs of murine embryos and therefore seems to be important for the process of resegmentation. Quail embryos do not possess permanent intervertebral discs. Hyper- or hyposegmentation defects may be explained by an over- or under-expression of Pax-1 during development. We also reinvestigated the border between the head and trunk in chick embryos by performing homotopical grafting experiments of the 5th somite between chick and quail embryos. Grafted quail cells formed mainly the caudal end of the basioccipital bone. They were also located in the cranial half of the ventral atlantic arch, and only a few cells were found in the tip of the dens axis.  相似文献   
993.
BACKGROUND: Heartburn, a common symptom, is self-treated with oral antacids. Efficacy of antacids has not been demonstrated for individual, spontaneous heartburn episodes. METHODS: We conducted a double-blind, randomized, placebo-controlled, parallel-group study of self-directed treatment for episodic heartburn comparing famotidine (FAM) 5, 10, or 20 mg and antacid (11 mEq ANC) to placebo (PBO) during a 4-week period. Twenty-nine US investigators enrolled a total of 565 outpatients, ages 18--81 years (mean 44.1 years) with heartburn but not seeking care for heartburn. Treatment of spontaneous heartburn episodes was permitted as needed, up to twice daily, with self-administered test drug. An open-label, backup antacid was provided to use if test drug did not provide adequate relief. Patients assessed heartburn relief hourly and recorded use of backup antacid. Relief was defined as complete relief of symptoms without the use of backup antacid. RESULTS: The media proportion of episodes relieved was: PBO, 41%; FAM 5 mg, 59%, 0.05 less-than-or-equal p < 0.10; FAM 10 mg, 70%, p < 0.001; FAM 20 mg, 69%, p < 0.001; antacid, 62%, p < 0.05 (p-values versus PBO). Supplemental analyses incorporating time to relief confirmed that famotidine and antacid provided more rapid and more frequent relief than placebo (odds ratio for relief relative to PBO: FAM 5 mg, 1.55, p = 0.003; FAM 10 mg, 1.94, p < 0.001; FAM 20 mg, 2.13, p < 0.001; antacid 1.57, p = 0.003). The tolerability profile was similar with famotidine, antacid, and placebo. CONCLUSIONS: The positive results with antacid demonstrated for the first time the efficacy of antacid in self-treatment of individual heartburn episodes and provided internal validation of this study paradigm. Patients in this study self-medicated effectively using low doses of famotidine on an as needed basis for spontaneous episodes of heartburn.  相似文献   
994.
Receptor-induced binding of the stable GTP analogue, guanosine 5-[-thio]triphosphate (GTP [S]), to guanine nucleotide-binding regulatory proteins (G proteins) was measured in various permeabilized cells. In myeloid differentiated human leukemia (HL-60) cells, permeabilized with either digitonin, streptolysin O or Staphylococcus aureus -toxin, binding of GTP [S] induced by three distinct chemoattractant receptors was observed. The extent of receptor-stimulated GTP [S] binding (maximally about 2-fold) was independent of the type of permeabilizing agent used. In human erythroleukemia cells permeabilized with digitonin, agonist activation of thrombin and neuropeptide Y receptors increased GTP [S] binding by 1.8- and 1.5-fold, respectively. Finally, in adherently grown human embryonic kidney cells permeabilized with digitonin, activation of the stably expressed human muscarinic m3 receptor increased GTP[S] binding by about 1.6-fold. In digitonin-permeabilized HL-60 cells, a quantitative analysis of formyl peptide receptors and interacting G proteins was performed. About 50,000 formyl peptide receptors per cell were detected. Agonist binding to these receptors was fully sensitive to regulation by guanine nucleotides and pertussis toxin. The number of high-affinity GTP [S] binding sites, most likely representing heterotrimeric G proteins, was calculated to be about 670,000 per cell. Stimulation of formyl peptide receptors led to the activation of about 130,000 of high-affinity GTP [S] binding sites, indicating a ratio of about three activated G proteins per one agonist-activated receptor.Overall, this study indicates that receptor-stimulated GTP [S] binding to G proteins in permeabilized cells is a sensitive and rapid method for analyzing receptor-G protein interactions, which can be applied to a variety of cultured cells and for various receptor systems.  相似文献   
995.
996.
Serotonergic mechanisms of cocaine effects in humans   总被引:1,自引:0,他引:1  
The objective of this study was to investigate the role of serotonin (5-HT) in mediating the effects of cocaine in humans. To accomplish this, 12 subjects each participated in two randomized, double-blind test sessions separated by 1 week. In one session, subjects underwent acute depletion of the 5-HT amino acid precursor tryptophan (TRP), followed by a test dose of intranasal cocaine. In the other session, the cocaine test dose was preceded by sham depletion. Subject ratings of cocaine high were significantly lower following active TRP depletion than after the sham procedure. Subjects also showed an earlier but less sustained rise in self-rated nervousness during active TRP depletion. These findings are consistent with the hypothesis that 5-HT may be involved in mediating the euphorigenic and modulating the anxiogenic effects of cocaine in humans, either directly or through actions on other (e.g., dopaminergic) systems.  相似文献   
997.
Reconstruction after gastrectomy and quality of life   总被引:30,自引:0,他引:30  
To evaluate quality of life and functional results following surgery for gastric cancer we studied 104 patients with no evidence of disease at a minimum of 12 months postoperatively. Patients were treated with total gastrectomy and jejunal pouch reconstruction according to Hunt-Lawrence-Rodino (n=59) or simple esophagojejunostomy (n=24) and distal subtotal gastrectomy (n=21). No significant differences were found between total gastrectomy with pouch reconstruction and distal gastric resection with respect to dumping or heartburn, whereas patients with total gastrectomy and restoration with esophagojejunostomy suffered from both. The latter group of patients also had reduced nutritional status. Although there is a lack of a proper definition of quality of life, all instruments applied to its measurement indicated improved results for patients with pouch reconstruction and those after distal gastrectomy, but we could not state any significant differences. We conclude that in terms of postoperative functional results as well as quality of life distal gastric resection has no advantage over total gastrectomy with pouch reconstruction; hence a reduction of surgical radicality in an attempt to improve postoperative results is not justified. Pouch reconstruction should be considered the treatment of choice for reconstruction after total gastrectomy.
Resumen Con miras a evaluar la calidad de la vida y los resultados funcionales luego de cirugía por cáncer gástrico, estudiamos 104 pacientes que se encontraban libres de enfermedad a un mínimo de 12 meses postoperatorios. Los pacientes fueron tratados con gastrectomía total y reconstrucción con una bolsa yeyunal de tipo Hunt-Lawrence-Rodino (n=59) o simple esofagoyeyunostomía (n=24) y gastrectomía subtotal distal (n=21). No se encontraron diferencias significantivas entre los pacientes sometidos a gastrectomía total con reconstrucción con bolsa yeyunal y los sometidos a resección distal con respecto a dumping o pirosis, en tanto que los pacientes sometidos a gastrectomía total y restauración mediante esofagoyeyunostomía exhibieron ambos síntomas. Además, los últimos desarrollaron deterioro de su estado nutricional. Aparte de la falta de una adecuada definición de calidad de la vida, todos los parámetros aplicados para su medición demostraron mejores resultados en los casos de gastrectomía total con reconstrucción con bolsa yeyunal y en los casos de gastrectomía distal, pero sin que pudiéramos hallar diferencias significativas. Nuestra conclusión es que en términos de los resultados funcionales postoperatorios así como de calidad de la vida, la resección gástrica distal no tiene ventaja sobre la operación con reconstrucción con bolsa yeyunal y que no se justifica una reducción de la radicalidad quirúrgica con el objeto de mejorar los resultados postoperatorios. La reconstrucción con bolsa yeyunal debe ser considerada como el procedimiento de elección en la gastrectomía total.

Résumé Afin d'évaluer la qualité de vie et les résultats fonctionnels après chirurgie pour cancer gastrique, nous avons étudié 104 patients qui semblaient guéris à 12 mois. Les patients ont eu soit une gastrectomic totale suivie ou de la confection d'un néogastre jéjunal selon le procédé de Hunt-Lawrence-Rodino (n=59) ou une simple anastomose oesojéjunale (n=24), soit d'une gastrectomie distale subtotale (n=21). Il n'y avait aucune différence significantive entre la gastrectomie totale suivie de reconstruction par néogastre et la gastrectomie distale subtotale en ce qui concerne le dumping syndrome ou le reflux, alors que les patients qui avaient eu une gastrectomie totale suivie d'anastomose oesojéjunale avaient les deux. Chez ces derniers, on a également noté une certaine malnutrition. En dépit du manque de définition précise de la qualité de vie, tous les moyens utilisés pour la mesurer ont indiqué um meilleur résultat pour les patients ayant eu une reconstruction avec néogastre par rapport à la gastrectomie distale, sans toutefois atteindre la signification statistique. Nous concluons qu'en terme de résultats fonctionnels postopératoires ainsi que de la qualité de vie, la gastrectomie distale ne présente aucun avantage par rapport à la gastrectomie totale suivie de néogastre, et une réduction dans l'importance de l'intervention pour améliorer les résultats fonctionnels n'est pas justifiée. La confection d'un néogastre doit être la méthode de reconstruction de choix après gastrectomie totale.
  相似文献   
998.
In previous experimental liver transplant studies, it was possible to extend cold ischaemic time (CIT) by using a flush/storage solution combining histidine, lactobionate and raffinose (HLR). In this study, energy metabolism, glycolytic substrate (glucose) and anaerobic end-product (lactate) were examined in rat liver over 24 h of cold storage to determine the mechanism of action of the HLR solution. In livers subjected to simple flush and storage with the HLR solution. levels of ATP and ADP were considerably higher than livers stored with modified UW throughout 24 h of storage; at 4 h of storage, ATP and ADP levels were 1.1 and 3.1 mol/g for HLR solution versus 0.18 and 0.81 mol/g for UW solution. Total adenylate contents (TA=ATP+ADP+AMP) also remained 1–2 mol/g higher in HLR-treated livers than those preserved in UW; TA values ranged from 3.8 to 5.7 mol/g. Glucose increased to 20–35 mol/g by 10–24 h of storage (similar to the UW group). Lactate rose to almost twice that in livers stored in UW; total lactate accumulation was approximately 10.0 mol/g. This study demonstrated that the combined HLR solution is able to prolong the maximum safe CIT by increasing anaerobic metabolism and consequently preserving liver energetics. The second part of the experiment examined the effect of continuous perfusion (with/without O2) over the 1st h of cold ischaemia. Under current methods of liver flushing and excision, the 1st h of cold storage may be the critical time of metabolic adjustment since most of the pH and ATP changes occur during this period. Therefore, we tested the hypothesis that the combination of a simple flush with an additional brief 1-h perfusion period prior to storage would enhance the maintenance of hepatic energetics. There was no beneficial effect of 1 h of perfusion without O2 compared to simple HLR flush and storage. However, perfusion with O2 resulted in prolonged maintenance of high energy adenylates and total adenylates; at 10 h of storage ATP was 1.0, ADP 3.3, and TA 5.7 mol/g. However, any improvement in ultimate viability following long-term storage of the livers in these two groups needs to be tested in an animal transplant model.  相似文献   
999.
Calcium balance and intact PTH variations during haemodiafiltration   总被引:1,自引:1,他引:0  
BACKGROUND.: Recent approaches to prevent and treat secondary hyperparathyroidismin dialysis patients include decreasing dialysate Ca contentfrom 1.75 to 1.5 mM or lower. We have recently observed thatby decreasing dialysate Ca to 1.25 mM a rise in intact parathormoneserum levels occurs despite adequately controlled predialysisCa and phosphate serum levels. In that study complementary treatmentwith high-dose 1(OH) vitamin D3 was required to suppress theparathormone. In the present study we aimed to assess the totalCa balance as well as the modifications in parathormone inducedby the dialysis session in order to understand the reasons forwhich the rise in parathormone was induced. METHODS.: Fourteen HD patients treated with haemodi-afiltration threetimes/week gave their informed consent for the study. They weredistributed in two groups with identical treatment but for thedialysate Ca content which was 1.5 and 1.25 mM respectivelyand for the amount of oral CaCO3 received. Total and ionizedCa, phosphate, pH, and albumin as well as parathormone weremeasured in serum before and after dialysis and in the spentdialysate during two dialysis sessions. RESULTS.: Serum ionized Ca (normalized to pH 7.4) did not change during1.25 mM dialysate Ca and significantly increased with 1.5mM(P<0.001). The end-dialysis values being 1.25±0.02and 1.38±0.02 mM respectively. Total Ca significantlydecreased with 1.25mM dialysate Ca (P<0.04) and increasedwith 1.5mM (P<0.003), the end-dialysis values being 2.51±0.03and 2.75±0.04mM respectively. In the dialysate the differencein ionized Ca concentrations, fresh minus spent dialysate was–1.78±1.12 mmol/l (NS) and 4.26±1.47 mmol/l(P<0.02) respectively for 1.25 and 1.5 mM dialysate Ca. Thedifference in total Ca concentrations, fresh minus spent dialysatewas –0.1±0.01 mmol/l (P<0.005 and –0.002±0.01 mmol/l (NS) respectively. Phosphate removal was higherin 1.25 mM dialysate-Ca-treated patients (40.4±1.75 mmol/sessionversus 34±1.3 mmol/session respectively, P<0.015).The use of 1.25 mM dialysate Ca did not result in a change inserum parathormone, while the use of 1.5 mM resulted in a decreaseof 43±15% (P<0.02) in patients with marked hyperparathyroidism. CONCLUSIONS.: Our data remind us of the difficulty in assessing Ca balancesand identifies the phosphate content as one of the factors influencingthe amount of ionized Ca in the dialysate. Although the long-termparathormone increase we observed using 1.25 mM dialysate Camay well not be explained only by the acute intradialytic modifications,the negative Ca balance identified here (which was missed withthe analysis of ionized Ca alone), and the lack of parathormoneinhibition may participate in the relapse of hyperparathyroidism.  相似文献   
1000.
Depression in electroencephalogram (EEG) has been documented clinically and is reproducible in swine at the initiation of cardiopulmonary bypass (CPB) utilizing a crystalloid prime. The physiological cause of this transient alteration in electrical brain activity appears to be associated with the transient drop in arterial pressure. The etiology is unknown but may be attributable to the bolus of the crystalloid prime or micro emboli, either air or fibrin-platelet. Thirteen swine (17-26 kg) were anesthetized and received 4 mg/kg dexamethasone, and following a tracheotomy were ventilated with halothane in 100% O2. Surgical preparation included: sternotomy and preparation for right atrial-aortic CPB. The CPB circuit consisted of a hollow fiber membrane oxygenator, a hard-shell venous reservoir, a roller pump, and PVC tubing. The circuit was randomly primed with either 1200 ml Plasmalyte-A or 10 ml/kg perfluorocarbon emulsion (PFE) and Plasmalyte-A to total 1200 ml. The animals were monitored continuously for systemic hemodynamics and electrocardiogram, and cerebral monitoring included blood flow and bitemporal EEG. Arterial blood gases were measured and PaCO2 was kept between 30-45 mmHg both before and during CPB. Cerebral blood flow (CBF) was measured pre-CPB and at 10 minutes after initiation of CPB. Bitemporal computerized EEG was analyzed every 60 seconds. Total power of each hemisphere, power in frequency bands, and spectral edge were recorded. All animals demonstrated a relative decrease in EEG total power at the onset of CPB. Animals that received PFE demonstrated a more stable arterial blood pressure, an increased CBF, and a lesser decrease and an earlier recovery of the EEG power.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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