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61.
From the roasted seeds ofCassia tora L., a new naphthopyrone glycoside was isolated and characterized as 10-[(β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl)oxyl-5-hydroxy-8-methoxy-2-methyl-4H-naphtho [1,2-b]pyran-4-one(isorubrofusarin gentiobioside). Along with isorubrofusarin gentiobioside, alaternin and adenosine were isolated and identified.  相似文献   
62.
The experimental hepatic cirrhosis was induced either by bile duct ligation (BDL) or by pretreatment with dimethylnitrosamine (DMNA). The pharmacokinetics of theophylline were studied after a single intravenous or a single oral administration. Using the ultrafiltration method, protein-drug binding experiments were also carried out. The bilirubin level was several-fold increased by BDL, but not by DMNA treatment. The albumin content was decreased in both cirrhotic groups. The total clearance (Clt, ml/kg/hr) of theophylline in both hepatic cirrhosis groups significantly decreased and the terminal half-life (t1/2) in the cirrhotic rats was increased about two-fold after intravenous and oral administration. The volume of distribution at steady state (Vdss, ml/kg) was increased slightly in the cirrhotic groups. Protein binding in BDL (8.67±4.85%) decreased about four-folds, but in DMNA (73.00±9.85%) similar result, was observed as compared with the control. Increased free fraction of theophylline did not increase the volume of distribution in BDL. Therefore decreased total body clearance of theophylline was mainly due to decreased intrinsic clearance of theophylline in the liver. The absolute bioavailability of theophylline in these experiments was between 63.8 and 72.8%(66.1% in BDL, 63.8% in Sham operated and Control, 72.8% in DMNA). These results suggest that in the experimental hepatic cirrhosis model, administration route does not affect the disposition of theophylline.  相似文献   
63.

Background

To assess the accuracy of rest and treadmill exercise first-pass radionuclide ventriculographic measurements of left ventricular ejection fraction (LVEF), 40 patients underwent treadmill exercise first-pass and bicycle exercise equilibrium radionuclide ventriculography. To determine the frequency of technically adequate treadmill exercise first-pass studies, an additional 128 consecutive patients undergoing treadmill exercise first-pass procedures during stress99mTc-labeled sestamibi myocardial perfusion studies were assessed.

Methods and Results

The treadmill exercise first-pass procedure used a multicrystal camera and an241Am point source to allow for correction of patient motion. Excellent correlations were observed between resting first-pass and resting equilibrium LVEF (r=0.91; standard error of the estimate=5.6). A high correlation was also observed between treadmill exercise first-pass and bicycle equilibrium exercise LVEF measurements (r=0.85, standard error of the estimate=7.6). Treadmill first-pass LVEF systematically underestimated the bicycle equilibrium LVEF. Intraobserver agreement for rest and exercise first-pass LVEF was high (r values of 0.98 and 0.94, respectively). Of the 168 consecutive treadmill exercise first-pass studies evaluated for technical adequacy, 21 (12.5%) were deemed technically inadequate, with most of the sources of error being avoidable. The frequency of technically adequate studies was as high (87%) in high levels of exercise (Bruce stages 3 and 4) as in lower levels (88%). The findings of this study validate the first-pass treadmill exercise LVEF measurement.

Conclusion

This procedure now provides the option for combining the information of peak treadmill exercise LVEF with measurements of exercise myocardial perfusion from the same injection of radioactivity.  相似文献   
64.
The activity of S-famesylcysteine O-methyltransferase was assayed by incubating the enzyme with a syntheticin vitro substrate, [N-acetyl-S-trans, trans-famesyl-L-cysteine (AFC)], together with S-adenosyl-L-[methyl-14C]methionine. The resulting methylesterification product, [N-acetyl-S-trans, trans-famesyl-L-cysteine (methyl-14C) ester (AFCME)], was then analyzed either directly on HPLC or by converting the AFC[methyl-14C]ME to [methyl-14C] alcohol by basehydrolysis. Employing these two analytical methods, it was established that a peptide purified from rat liver cytosol fraction [Int. J. Biochem., 25, 1157 (1993)] strongly inhibited the above enzyme activity with IC50 of 7.1X10?8 M. Also, the S-famesylcysteine O-methyltransferase from several human colon cancer cells was also equally inhibited by the peptide.  相似文献   
65.
The authors report a typical case of tenosynovial giant cell tumor of the right middle finger of a 31-year-old man. Histologically, this tumor is characterized by a discrete proliferation of rounded synovial-like cells accompanied by a variable number of multinucleated giant cells, inflammatory cells, and xanthoma cells. Clinicopathologically, this tumor is a benign lesion that nonetheless possesses a capacity for local recurrence. Local excision with a small cuff of normal tissue is the treatment of choice in this tumor.  相似文献   
66.
Hwang Y  Feiss M 《Virology》1999,265(2):196-205
Terminase, the DNA packaging enzyme of bacteriophage lambda, is a heteromultimer composed of gpNu1 (181 aa) and gpA (641 aa) subunits, encoded by the lambda Nu1 and A genes, respectively. Similarity between the deduced amino acid sequences of gpNu1 and gpA and the nucleotide binding site consensus sequence suggests that each terminase subunit has an ATP reactive center. Terminase has been shown to have two distinct ATPase activities. The gpNu1 subunit has a low-affinity ATPase stimulated by nonspecific DNA and gpA has a high-affinity ATPase. In previous work, a mutant terminase, gpNu1 K35A holoterminase, had a mild defect in interactions with DNA, such that twofold increased DNA concentrations were required both for full stimulation of the low-affinity ATPase and for saturation of the cos cleavage reaction. In addition, the gpNu1 K35A terminase exhibited a post-cleavage defect in DNA packaging that accounted for the lethality of the Nu1 K35A mutation [Y. Hwang and M. Feiss (1997) Virology 231, 218-230]. In the work reported here, a mutation in the turn of the putative helix-turn-helix DNA binding domain has been isolated as a suppressor of the gpNu1 K35A change. This suppressor mutation causes the change A14V in gpNu1. A14V reverses the DNA-binding defects of gpNu1 K35A terminase, both for stimulation of the low-affinity ATPase and for saturation of the cos cleavage defect. A14V suppresses the post-cleavage DNA packaging defect caused by the gpNu1 K35A change.  相似文献   
67.
Gabapentin in the acute treatment of refractory bipolar disorder   总被引:4,自引:0,他引:4  
Background: Gabapentin, a new anti-epileptic agent, has been anecdotally reported to be effective in the treatment of mania. We systematically assessed the response rate in bipolar patients being treated adjunctively with gabapentin for manic symptoms, depressive symptoms, or rapid cycling not responsive to standard treatments.
Method: Twenty-eight bipolar patients experiencing manic (n=18), depressive (n=5), or rapid-cycling (n=5) symptoms inadequately responsive to at least one mood stabilizer were treated in an open fashion with adjunctive gabapentin. Illness response was assessed using the Clinical Global Impression Scale modified for bipolar disorder (CGI-BP). A 'positive response' was operationalized as a CGI response of much or very much improved.
Results: Fourteen of the 18 (78%) treated for hypomania or mania had a positive response to a dosage range of 600–3600 mg/day. Patients with hypomania responded fastest, with a positive response achieved in 12.7±7.2 days. Patients with classic mania had a mean time to positive response of 25±12 days, and in patients with mixed mania it was 31.8±20.9 days. All of the five patients treated for depression had a positive response within 21±13.9 days. Only one of five patients with rapid cycling had a positive response. Gabapentin was well tolerated by all patients, with the most common side-effect being sedation.
Conclusions: Gabapentin appears to have acute anti-manic and anti-depressant properties as an adjunctive agent for refractory bipolar illness. Prospective double-blind studies are needed to further delineate its acute efficacy when used as monotherapy and its prophylactic efficacy as monotherapy or in conjuction with other mood stabilizers.  相似文献   
68.
Technetium-99m labeled diethylenetriaminepentaacetic acid (DTPA)-galactosyl human serum albumin (GSA) has been used for hepatocellular functional evaluation. This study proposed new and simple parameters to overcome the limitations of conventional parameters, and they were applied to the clinical staging of chronic liver dysfunction. The study group consisted of 93 patients including 81 with liver dysfunction and 12 control patients. In addition to the two conventional parameters, namely, receptor index (LHL15 = liver count divided by the sum of liver and heart counts at 15 minutes) and clearance index (HH15 = heart count at 15 minutes divided by the heart count at 3 minutes), 6 new parameters for Tc-99m GSA uptake and clearance were generated. The conventional receptor index of LHL15 showed a large variation depending on the size of region of interest (ROI) over the heart. The LHL15 normalized by the ROI size (nLHL15) showed more stable data and a better separation of mild liver dysfunction. A hyperbolic relationship between the LHL15 and HH 15 changed to a linear relationship by using the nLHL15 index. The combination of the liver to heart average count ratio at 15 minutes (LH 15) and T-half (minute) of the heart count also could differentiate each stage well. In conclusion, the use of the ROI-area normalized nLHL is recommended instead of the conventional LHL15. The indices of LH15 and T-half could be alternatively used as practical parameters for clinical staging in liver function.  相似文献   
69.
Lee BC  Hwang SH  Chang GY 《Neurology》1999,52(3):646-648
Eight older women from two different continents, all with nonketotic hyperglycemia, presented with hemiballismus-hemichorea (HB-HC) and high signal intensity in the contralateral striatum on T1-weighted MRI scans. Correction of underlying hyperglycemia and supportive care resulted in resolution within days to weeks. This characteristic clinicoradiologic picture suggests a clinical syndrome with benign outcome.  相似文献   
70.
The informal social interaction behavior that is typical of a high school lunchroom in which general and special education students are physically included was described. Using systematic observation and social comparison methods, we compared the performance of two groups of students (12 general education students and 12 students with mental retardation). Both similarities and differences were found in the interactions of students with mental retardation and their general education peers with respect to social behaviors, conversational topics, and context within which interactions occurred. However, despite being in proximity, students with mental retardation rarely interacted with any of approximately 500 general education students present in the lunchroom. Implications are discussed for increasing social interaction among high school students.  相似文献   
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