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991.
992.
Background: Several studies on left ventricular relaxation have been undertaken in the past: however, left atrial (LA) relaxation has not been fully evaluated. Hypothesis: The purpose of this study was to assess abnormalities in LA relaxation by evaluating pulmonary venous flow velocity and interatrial septal motion using transesophageal echocardiography. Methods: The subjects were 56 untreated patients in sinus rhythm, including 25 with previous myocardial infarction, 9 with hypertrophic cardiomyopathy, 11 with dilated cardiomyopathy, as well as 11 with chest pain syndrome as controls. Peak first systolic velocity (PVS1), peak atrial systolic velocity (PVA), and their time-velocity integrals (PVS1-I and PVA-I, respectively) were calculated from the pulmonary venous flow velocity. Results: The PVS1 and PVS1-I correlated negatively with the maximum LA dimension and mean pulmonary capillary wedge pressure, and correlated positively with the amplitude of the interatrial septal motion during LA relaxation and percent fractional LA relaxation. The PVA and PVA-I did not correlate with the mean pulmonary capillary wedge pressure. There was a weak positive correlation between PVA and PVS1, and a close positive correlation between the ratio of PVA to PVS1 and mean pulmonary capillary wedge pressure. Multiple regression analysis indicated that the PVS1 was most closely related to percent fractional LA relaxation, followed by mean pulmonary capillary wedge pressure. Conclusion: The PVS1 determined from the pulmonary venous flow velocity is closely related to parameters of LA relaxation which may be determined by transesophageal M-mode echocardiography, and the ratio of PVA to PVS1 is useful for noninvasive evaluation of LA pressure..  相似文献   
993.
994.
BACKGROUND/AIMS: Minimally invasive surgery, with its advantages of early return to normal activity and good cosmetic results, is an important goal in the treatment of patients with mucosal ulcerative colitis. The aim of this study was to compare outcomes utilizing a mini-laparotomy approach to total abdominal colectomy for mucosal ulcerative colitis with those of the conventional approach. METHODOLOGY: Eleven patients scheduled to undergo the first (total abdominal colectomy) of a 2 or 3-stage operation for mucosal ulcerative colitis via a mini-laparotomy between 1999 and 2001 were prospectively studied. The mini-laparotomy described here involves total abdominal colectomy performed through a skin incision shorter than 7 cm. Seven similar patients who underwent conventional laparotomy between 1995 and 1998 served as the control group. RESULTS: The mini-laparotomy approach was accomplished in 9 patients (81.8%). Patient characteristics between cases and controls were similar. Postoperative intervals until standing, walking, flatus, urinary catheter removal, and tolerance of solid diet were significantly shorter in the mini-laparotomy group (P = 0.031, P = 0.023, P = 0.0033, P = 0.0093, and P = 0.023, respectively). CONCLUSIONS: A mini-laparotomy approach to total abdominal colectomy appears feasible and safe in selected patient with mucosal ulcerative colitis and poses an attractive alternative to conventional laparotomy in patients similar to those presented here.  相似文献   
995.
Two new triterpenoids, 20(21)-dehydrolucidenic acid A (1) and methyl 20(21)-dehydrolucidenate A (2), and five new 20-hydroxylucidenic acids, 20-hydroxylucidenic acid D(2) (3), 20-hydroxylucidenic acid F (4), 20-hydroxylucidenic acid E(2) (5), 20-hydroxylucidenic acid N (6), and 20-hydroxylucidenic acid P (7), were isolated from the fruiting body of the fungus Ganoderma ludicum, and their structures were established on the basis of spectroscopic methods.  相似文献   
996.
Eleven new indole alkaloids, in addition to the previously reported rhazinal (1), and 14 other known alkaloids, were obtained from the Malayan Kopsia singapurensis, viz., kopsiloscines A-F (2-7), 16-epikopsinine (8), kopsilongine- N-oxide (9), 16-epiakuammiline (10), aspidophylline A (11), and vincophylline (12). The structures of these alkaloids were determined using NMR and MS analyses. Rhazinal (1), rhazinilam (17), and rhazinicine (18) showed appreciable cytotoxicity toward drug-sensitive as well as vincristine-resistant KB cells, while kopsiloscines A (2), B (3), and D (5) and aspidophylline A (11) were found to reverse drug-resistance in drug-resistant KB cells.  相似文献   
997.
The partial amino acid sequence of the amyloid fibril protein isolated from the small intestine of a patient with plasma cell dyscrasia and associated amyloidosis has been determined and compared with the sequence of the kappa-type Bence Jones protein isolated from the urine of the same patient. Identical sequences were observed for the 27 amino-terminal residues that could be compared. The C-terminal tryptic peptide of the amyloid protein was identical with that of the Bence Jones protein. Apparent molecular weights and amino acid compositions of the Bence Jones and amyloid proteins were similar. It appears, therefore, that the predominant protein present in the amyloid deposits in this patient was an intact kappa-type light polypeptide chain that was identical with the urinary Bence Jones protein.  相似文献   
998.
999.
The present investigation focused on the transepithelial flux of liquiritigenin (LG), davidigenin (DG), liquiritin (LQ), and liquiritin apioside (LA) using the human colonic cell line Caco-2 as a model of human intestinal absorption. Apparent permeability coefficients (Papp) for the apical to basolateral flux of LG and DG were (16.0 +/- 0.727) x 10(-6) cm/s and (18.2 +/- 1.67) x 10(-6) cm/s, respectively. These Papp were higher than that of the transcellular transport marker propranolol (13.5 +/- 0.34) x 10(-6) cm/s (P < 0.01). Papp for the apical to basolateral flux of LQ and LA were (0.26 +/- 0.12) x 10(-6) cm/s and (0.075 +/- 0.005) x 10(-6) cm/s, respectively. These Papp were lower than that of the paracellular transport marker mannitol (0.64 +/- 0.04) x 10(-6) cm/s (LG, P < 0.01; LA, P < 0.001). These data suggested excellent absorption of LG and DG through the human intestinal epithelial cell line. On the contrary, poor absorption of LQ and LA was expected due to the little transepithelial flux of these compounds in the human colonic cell line Caco-2.  相似文献   
1000.
The structure of a novel major carotenoid glycoside (nearly 80% of total carotenoids) from a newly isolated bacterium, Paracoccus schoinia NBRC 100637T, was determined to be adonixanthin diglucoside using spectral data. By contrast, carotenoid diglycosides are rare and are usually minor carotenoids in nature. The minor carotenoids in this bacterium included astaxanthin diglucoside, zeaxanthin diglucoside, canthaxanthin, echinenone, zeaxanthin, beta-cryptoxanthin, and beta-carotene.  相似文献   
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