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AP Evan DP Henry BA Connors P Summerlin WH Lee 《Canadian Metallurgical Quarterly》1995,48(5):1517-1529
Immunocytochemistry, in situ hybridization, and radioimmunoassay were employed to examine the cellular distribution of mRNAs and proteins for IGF-I, II, IGF-II/M6P receptor, IGFBP2 as well as the levels of IGF-I and II in normal and unilaterally nephrectomized (Nx) adult rat kidneys. A similar distribution of immunoreactive IGF-I, and -II as well as IGF-II/M6P receptor was found in the principal cells of the cortical collecting duct and in all cells of the inner medullary collecting duct. In addition, immunostainable IGF-I and IGF-II/M6P receptor were noted in some inner medullary loops of Henle, while IGFBP2 was seen in the collecting ducts and loops of Henle of the inner medullar and the renal vasculature of all animals. By comparison, in situ hybridization revealed IGF-I mRNA only in the medullary thick ascending limbs while IGF-II mRNA was localized to the wall of the renal microvasculature in all kidneys. IGFBP2 mRNA was localized to the renal corpuscle and to inner medullary interstitial cells of all kidneys. These data suggest that renal IGF-I and IGFBP2 are synthesized at upstream sites along the nephron and then transported downstream for interaction with IGF receptors. Following nephrectomy, the renal levels of IGF-I peptide and mRNA were elevated at both 5 and 33 days post-nephrectomy, supporting a potential functional role for IGF-I in stimulating the structural and functional recovery in compensatory hypertrophy. 相似文献
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TD Ruddy JM Wright D Savard SP Handa A Chockalingam AP Boulet 《Canadian Metallurgical Quarterly》1995,9(3):413-420
The efficacy and safety of optimally titrated once-daily (CD) and twice-daily (SR) diltiazem were compared in 111 patients with mild to moderate systemic hypertension [seated diastolic blood pressure (DBP) > or = 95 mmHg and < or = 114 mmHg] in a multicenter, randomized, double-blind, placebo run-in, parallel-group trial. Following a 4 week washout and placebo-controlled run-in period, patients were randomized to receive diltiazem CD 180 mg and matching placebo (n = 54), or diltiazem SR 90 mg bid (n = 57). Total daily doses were titrated from 180 mg to 360 mg to achieve a goal of seated DBP < 90 mmHg during a 6 week titration period. The patients continued to receive their optimal dose for a 6 week follow-up period. Ninety-six (96) patients (diltiazem CD: 47, diltiazem SR: 49) completed the study protocol, with 60% of the diltiazem CD and 55% of the diltiazem SR patients achieving the goal of seated DBP of < 90 mmHg (p = 0.685). Although significant decreases occurred in seated and standing measurements of diastolic and systolic BP and heart rate with treatment in both groups, there were no significant differences between treatment groups. Both medications were well tolerated, with a similar frequency of adverse effects [diltiazem CD: 24/54 (37%) patients; diltiazem SR: 24/57 (42.1%) patients] with the most frequently reported adverse effects being headache and edema. 相似文献
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DJ Bjorkman DL Carr-Locke DR Lichtenstein AP Ferrari A Slivka J Van Dam DC Brooks 《Canadian Metallurgical Quarterly》1995,90(12):2128-2133
OBJECTIVES: Bile leaks are a well documented complication of biliary surgery, occurring more frequently with laparoscopic procedures. Endoscopic therapy with a long biliary endoprosthesis traversing the site of the leak is effective. We have evaluated the hypothesis that equalizing biliary and duodenal pressures with a short transpapillary stent is an equally effective therapy for bile leaks. METHODS: Thirty one consecutive patients presenting over a 52-month period with postsurgical bile leaks were evaluated. Patients had been treated with long endoprostheses (stents or nasobiliary tubes), sphincterotomy, or short transpapillary stents. The success, complication rate, need for additional therapy, and hospitalization time of each therapeutic approach were determined. RESULTS: Endoscopic therapy was successful in all 25 patients in whom a bile leak could be documented. The clinical success, need for radiological drainage, length of hospitalization, and incidence of pancreatitis were similar for all methods of treatment. CONCLUSIONS: These results confirm that endoscopic therapy is highly successful in the treatment of postoperative bile leaks and suggest that the mechanism of healing is the equalization of bile duct and duodenal pressures, allowing flow of bile into the duodenum. The endoscopic placement of short transpapillary stents without sphincterotomy is a temporary, effective, and technically simple method of pressure equalization. This should be considered as the primary therapy for most postoperative bile leaks. 相似文献
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Xanthan production from Xanthomonas campestris was studied by a mechanically shaken fermentor. Influence of glucose concentration, aeration of culture media, rheology of broths and pH control was evaluated. Different aeration conditions based on variation of stirring rates were assayed. Substrate concentration was determined according to the Miller method, and polymer production was performed by the Cadmus method. The higher xanthan levels (i.e. 2.3%) were obtained at 750 rpm, with 1 v/v. min. In such conditions, viscosity ranges about 7000 cPoise and a low level of dissolved oxygen were detected in the culture medium. Xanthan production was influenced by the glucose concentration and the presence of amaranth within the culture medium. In the processes wherein an automatic control of pH was performed, the polymer concentration did not increase regarding to processes involving regular pH evolution. 相似文献
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