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71.
The effects of vasoactive intestinal polypeptide (VIP) and peptide histidine isoleucine (PHI) on the in vitro secretion of two prolactins (PRL) from the rostral pars distalis (RPD) and of growth hormone (GH) from the proximal pars distalis (PPD) of the pituitary of the tilapia (Oreochromis mossambicus) were studied. RPDs were incubated for 20 hr in hypoosmotic (280-300 mOsm) or hyperosmotic (340-350 mOsm) Krebs-Ringer bicarbonate medium with added peptide concentrations of 0 (control), 0.3, 3.0, 30, and 300 nM; similarly, PPDs were incubated with the same peptide concentrations in isoosmotic (325 mOsm) medium supplemented with cortisol. PRL and GH in the tissue and secreted into the medium were measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by soft laser densitometry of the protein band(s). Neither VIP nor PHI has a detectable effect on the secretion of GH. Secretion of the two PRLs is significantly inhibited by VIP and PHI in both hyperosmotic and hypoosmotic medium. In hyperosmotic medium, 300 nM VIP inhibits secretion of both PRLs by 47%, whereas in hypoosmotic medium, 300 nM VIP inhibits their secretion by 27%. PHI inhibits their secretion by ca. 65% in hyperosmotic medium and by 40% in hypoosmotic medium. There is preliminary immunocytochemical evidence for some VIP-like immunoreactivity (IR), but no conclusive indication of PHI-like IR, in the hypothalamo-hypophysial area. The inhibitory actions of VIP and PHI on PRL secretion in tilapia are in contrast to the known stimulatory actions of VIP and PHI on PRL secretion in tetrapods.  相似文献   
72.
Journal of Interventional Cardiac Electrophysiology - Clinical implication of local impedance (LI) for radiofrequency (RF) ablation has not been fully established. This study aimed to investigate...  相似文献   
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From December 1973 to December 1987, we performed a distal splenorenal shunt (DSRS) in 112 cases of portal hypertension, including 107 with postnecrotic liver cirrhosis and 5 with idiopathic portal hypertension (IPH). They comprised about 50% of our surgical cases with esophageal varices. In 1981, we modified our operative procedure towards a more extended splenopancreatic disconnection (SPD) in order to prevent the "stealing" of the shunt through the pancreatic vein. In one group of 69 patients who underwent DSRS alone, the operative mortality was 2.9%; postoperative encephalopathy was seen in 17.4%, late hepatic failure in 40.6%, and recurrence of varices in 4.3%. In the other group, 43 patients who underwent DSRS with SPD, there were no operative deaths, no encephalopathy (better than DSRS alone at p less than 0.05), and late hepatic failure was seen in only 9.3% (better than DSRS alone at p less than 0.025), while the recurrence rate of 7% was the only statistical increase. These data show that DSRS + SPD can improve chances of survival.  相似文献   
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With the sandwich binding protein assay utilizing hyaluronic acid binding protein, we measured serum concentration of hyaluronic acid in 458 healthy persons, 71 patients with rheumatoid arthritis (RA) and 51 patients with various rheumatic diseases such as osteoarthritis (OA), progressive systemic sclerosis (PSS), systemic lupus erythematosus (SLE) and gout. The mean concentration +/- standard deviation (SD) of healthy persons whose age ranged 2 to 92 years old was 38.5 +/- 35.7ng/ml, and those with over 50 years old had apparently higher concentrations (51.9 +/- 40.5ng/ml) than those with below 50 of age (20.6 +/- 14.8ng/ml). When the upper limit of normal range was set up at 130 ng/ml, abnormal percentages were 62.0% (44/71) in RA, 0% (0/18) in OA, 6.3% (1/16) in PSS, 18.2% (2/11) in SLE and 0% (0/6) in gout. Patients who apparently had arthritis but not RA revealed normal or near to the upper limit in serum hyaluronic acid compared to RA patients having the mean +/- SD of 351.4 +/- 463.7ng/ml. When patients with RA were classified into stage I to IV with X ray of bone destruction, patients with more advanced X ray stage showed significantly higher serum concentrations of hyaluronic acid. Similarly, patients with lower activity of daily living revealed significantly higher serum concentrations of hyaluronic acid. In addition, serum hyaluronic acid level did correlate to concentration of serum CRP and sialic acid. Lansbury's index, strength of grip, joint score and erythrocyte sedimentation rate, but did not to duration of morning stiffness and titer of rheumatoid factor.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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OBJECTIVE: Fas-mediated apoptosis is associated with the pathophysiology of rheumatoid arthritis (RA). However, the molecular mechanisms of this process remain to be elucidated in rheumatoid synovium. We investigated the behavior of intracellular signaling molecules that regulate Fas-mediated apoptosis in RA synoviocytes. METHODS: Anti-Fas monoclonal antibody (mAb) was added to RA synoviocytes after treatment with tumor necrosis factor alpha (TNFalpha) or basic fibroblast growth factor (bFGF) for 5 days. The cytotoxic activity was measured using a lactate dehydrogenase-release assay. The expression of apoptosis-related molecules in RA synoviocytes was examined by immunoblot analysis. The enzymatic activities of caspases 3 and 8 under Fas ligation were examined. Transfer of the FADD (Fas-associated death domain) protein and the FLIP(L) (long form of the FLICE [FADD-like interleukin-1beta-converting enzyme]-inhibitory protein) gene into RA synoviocytes was performed using adenoviral vectors. RESULTS: Following a 5-day treatment with TNFalpha or bFGF, Fas ligation with its agonistic mAb induced apoptosis of almost all TNFalpha-treated RA synoviocytes but only showed a weak apoptotic activity in bFGF-treated synoviocytes. Although there was no correlation between the induction of Fas-mediated apoptosis and the expression of apoptosis-related molecules among these cells, a high enzymatic activity of caspases 3 and 8 was observed only in the TNFalpha-treated RA synoviocytes after Fas ligation. The bFGF-treated RA synoviocytes were relatively resistant to apoptosis induced by FADD gene transfection, as compared with the TNFalpha-treated synoviocytes. In addition, the expression of FLIP(L), an inhibitory molecule of Fas-mediated apoptosis, was reduced in TNFalpha-treated RA synoviocytes, and the expression of FLIP43 was augmented in bFGF-treated RA synoviocytes. Moreover, Fas-mediated apoptosis in TNFalpha-treated RA synoviocytes was partially inhibited by FLIP(L) gene transfection. CONCLUSION: Our results suggest that Fas-mediated apoptosis of RA synoviocytes is differentially regulated by TNFalpha and bFGF. In addition, the regulatory mechanisms of apoptosis involve the formation of the death-inducing signaling complex, especially at the level of caspase 8 activation, and this process may be partly associated with FLIP expression.  相似文献   
79.
The records of 292 patients who were admitted to a teaching hospital from 1984 to 1990 in Uberlandia in southeastern Brazil after being bitten by snakes of the genus Bothrops were retrospectively surveyed. The patients were from 42 municipalities in three states of Brazil. Most (42%) bites occurred between 4:00 PM and 10:00 PM. Fourteen percent of the bites occurred in the month of April. In 54 (18%) of the cases, the snakes were captured and identified as belonging to the following species: B. moojeni (29), B. neuwiedi (18), and Bothrops species (7). A diagnosis was made based on clinical findings in 238 (82%) cases. The lower limbs were the commonest site of bite (74%). The median time interval between bite and admission to the hospital was 3 hr. Fang marks were recorded in 58% of the cases and swelling was recorded in 82%. Clotting time was greater than 15 min in (142 of 264) 54% of the cases. A tourniquet was used on 44 cases. The mean +/- SD dose of specific antivenom used was 187.48 +/- 93.44 mg. The complications that occurred included abscess formation in 18% of the cases, necrosis in 16%, and renal failure in 5%. Amputation was performed in three (1%) cases. The case fatality rate was also 1% (three cases). When all cases were analyzed, the chi-square test for trend showed an increased susceptibility of renal failure with age (P < 0.04). Clotting time greater than 15 min was associated with the development of abscesses (P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
80.
Plasma levels of activated protein C (APC)-protein C inhibitor (PCI) were significantly increased in patients with disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura (TTP), acute myocardial infarction (AMI), pulmonary embolism (PE), or deep vein thrombosis (DVT) and in patients undergoing hemodialysis (HD). Plasma levels of APC-alpha(1)-antitrypsin (AT) complex were significantly increased in patients with DIC and in those with TTP. Plasma levels of PCI were significantly decreased in patients with DIC, non-DIC, or TTP and in those undergoing HD. In the pre-DIC stage, the plasma levels of APC-PCI complex were significantly increased but not those of APC-alpha(1)-AT complex. These data suggest that measurements of APC-PCI complex and APC-alpha(1)-AT complex may be useful for the diagnosis of DIC. After treatment of DIC, the plasma levels of APC-PCI complex and APC-alpha(1)-AT complex were significantly decreased, but not those of PCI. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-alpha(2)-plasmin complex (PPIC), D-dimer, and soluble fibrin monomer (SFM) were markedly increased in patients with DIC or pre-DIC and were moderately increased in patients with non-DIC, TTP, AMI, PE, or DVT and in those undergoing HD. The receiving operating characteristic (ROC) analysis showed that SFM and the APC-PCT complex are useful markers for diagnosis of DIC. The specificity of plasma TAT and PPIC levels was low. The positive rate of APC-PCI complex was higher than 90% with DIC, TTP, AMI, PE, and it was higher than 60% with DVT and HD. Since the APC-PCI complex was elevated not only in patients with venous thrombosis but also in those with arterial thrombosis, components of the protein C pathway might be useful markers for the diagnosis of arterial thrombosis.  相似文献   
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