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101.
BACKGROUND: Embedded fetal bone after surgical termination of midtrimester pregnancy is a recognized complication. Most cases occur in the uterine cavity; however, this case demonstrates that a cervicovaginal fistula can be caused by embedment of bone in the cervical canal. CASE: A 19-year-old girl presented with persistent smelly vaginal discharge 4 years after surgical pregnancy termination. On examination she had a cervicovaginal fistula with embedded fetal bone that was subsequently removed surgically. CONCLUSION: Cervicovaginal fistula can be a complication of surgical termination of midtrimester pregnancy as fetal bones can become embedded in the cervical canal during removal. 相似文献
102.
K C Leung K P Fung C C Yu Y M Choy C Y Lee 《Clinica chimica acta; international journal of clinical chemistry》1977,74(1):43-49
The N-acetyl-beta-glucosaminidase activity in hydatidiform mole is two-fold higher than that in full-term placenta. Qualitatively, the enzymes from the two tissues are similar with respect to KM values and pH optima. Both enzymes also contain a new isoenzyme form detectable by polyacrylamide gel electrophoresis. However, the molar enzyme is more susceptible to heat denaturation, presumably due to the presence of a higher level of the heat-labile isoenzyme form A in this tissue. Data are also presented incicating that the placenta is not the source of the N-acetyl-beta-glucosaminidase activity in maternal serum. 相似文献
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Hepcidin, the liver-produced peptide hormone, is a principal regulator of iron homeostasis. Abnormal hepcidin production has emerged as a causative factor in several common iron disorders. Hepcidin insufficiency results in iron overload in hereditary hemochromatosis and iron-loading anemias, whereas hepcidin excess causes or contributes to the development of iron-restricted anemias in inflammatory diseases, infections, some cancers and chronic kidney disease. Not surprisingly, hepcidin and related pathways have become the target for the development of novel therapeutics for iron disorders. In this review, we will summarize the strategies and development programs that have been devised for agonizing or antagonizing hepcidin and its receptor ferroportin. 相似文献
106.
Brain G protein gamma subunits contain an all-trans-geranylgeranylcysteine methyl ester at their carboxyl termini. 总被引:14,自引:16,他引:14 下载免费PDF全文
H K Yamane C C Farnsworth H Y Xie W Howald B K Fung S Clarke M H Gelb J A Glomset 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(15):5868-5872
We have shown previously that guanine nucleotide-binding protein (G protein) beta gamma complexes purified from bovine brain membranes are methyl esterified on a C-terminal cysteine residue of the gamma polypeptide. In the present study, 3H-methylated G beta gamma complexes cleaved to their constituent amino acids by exhaustive proteolysis were shown to contain radiolabeled material that coeluted with geranylgeranylcysteine methyl ester on reversed-phase HPLC and two TLC systems. Further treatment by performic acid oxidation yielded radiolabeled material that coeluted with L-cysteic acid methyl ester, verifying that the prenyl modification occurs on a C-terminal cysteine residue. Analysis by gas chromatography-coupled mass spectrometry of material released from purified G beta gamma by treatment with Raney nickel positively identified the covalently bound lipid as an all-trans-geranylgeranyl (C20) isoprenoid moiety. To delineate the distribution of this modification among gamma subunits, purified G beta gamma complexes were separated into 5-kDa (gamma 5) and 6-kDa (gamma 6) forms of the gamma polypeptide by reversed-phase HPLC. Gas chromatography-coupled mass spectrometry analyses of Raney nickel-treated purified gamma 5 and gamma 6 subunits showed that both polypeptides were modified by geranylgeranylation. These results demonstrate that at least two forms of brain gamma subunit are posttranslationally modified by geranylgeranylation and carboxyl methylation. These modifications may be important for targeting G beta gamma complexes to membranes. 相似文献
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109.
Improvement of atrial function and atrial reverse remodeling after cardiac resynchronization therapy for heart failure. 总被引:2,自引:0,他引:2
Cheuk-Man Yu Fang Fang Qing Zhang Gabriel W K Yip Chun Mei Li Joseph Yat-Sun Chan LiWen Wu Jeffrey Wing-Hong Fung 《Journal of the American College of Cardiology》2007,50(8):778-785
OBJECTIVES: We sought to examine whether cardiac resynchronization therapy (CRT) improves atrial function and induces atrial reverse remodeling. BACKGROUND: Cardiac resynchronization therapy is an established therapy for advanced heart failure with prolonged QRS duration, which improves left ventricle (LV) function and is associated with LV reverse remodeling. METHODS: A total of 107 heart failure patients (66 +/- 11 years) who received CRT and were followed up for 3 months were studied. Atrial function was assessed by M-mode, 2-dimensional echocardiography, transmitral Doppler, tissue Doppler velocity, and strain (epsilon) imaging. Left atrial (LA) emptying fraction based on the change in areas (LAA-EF) and volumes (LAV-EF) were calculated. The LV reverse remodeling was defined by a reduction of LV end-systolic volume >10%. RESULTS: In the responders of LV reverse remodeling (n = 62), LAA-EF and LAV-EF were significantly increased (p < 0.001). Responders also had significant decrease in LA size area and volumetric measurements, both before (p < 0.05) and after atrial systole (p < 0.001). However, these parameters were unchanged in the nonresponders (n = 45, p = NS). In the responders, tissue Doppler velocity analysis showed improvement of contraction velocity in both left (p = 0.005) and right atria (p = 0.018), whereas epsilon in both atria were increased in all the phases of cardiac cycle, namely ventricular end-systole (p < 0.001), early diastole (p < 0.001), and late diastole (p = 0.007). CONCLUSIONS: Cardiac resynchronization therapy improves both left and right atrial pump function. The increase in atrial epsilon throughout the cardiac cycle is likely reflecting the improvement of atrial compliance. These changes lead to LA reverse remodeling with reduction of LA size before and after atrial systole. 相似文献
110.
BACKGROUND: Although several epidemiological surveys of Klebsiella clinical isolates have been performed, few studies have correlated the clinical isolate with disease. OBJECTIVE: To compare the clinical and bacteriological characteristics of Klebsiella pneumoniae bacteremia acquired as community or nosocomial infections. METHODS: We prospectively enrolled 158 consecutively hospitalized patients with K pneumoniae bacteremia. Clinical data were reviewed. Antimicrobial susceptibility testing and capsular serotyping were performed. We used the chi(2) test, the Fisher exact test, or the t test for statistic analysis. RESULTS: Underlying diabetes mellitus was more common in community-acquired than in nosocomial infection (46/94 [49%] vs. 8/64 [12%]; P<.001). On the other hand, neoplastic disease (34/64 [53%] vs. 13/94 [14%]; P<.001) and antibiotic resistance (P<.01) were more frequent in patients with nosocomial compared with community-acquired infections. Klebsiella pneumoniae liver abscesses, which were all community acquired, accounted for the source of 22 (23%) of 94 community-acquired K pneumoniae infections. No attributable source of infection was found for 37 (58%) of the 64 nosocomial infections vs. 15 (16%) of the 94 community-acquired infections. Only 58 isolates (36.7%) could be serotyped; of these, capsular serotypes K1, K2, and K28 accounted for 37 (23.4%), 8 (5.1%), and 6 (3.8%), respectively, of all strains. However, typeable isolates were significantly more common among community-acquired than nosocomial isolates (42/94 [45%] vs. 16/64 [25%]; P =.01), especially for serotype K1 (28/94 [30%] vs. 9/64 [14%]; P =.02). Significant risk factors for mortality included nosocomial infection, lung infection, thrombocytopenia, leukopenia, ceftazidime resistance, inappropriate antimicrobial therapy, and septic shock. CONCLUSIONS: Significant differences were identified between community-acquired and nosocomial K pneumoniae bacteremia. Ceftazidime resistance in nosocomial K pneumoniae bacteremia carried a high risk for mortality, and serotype K1 in K pneumoniae was more prevalent in community-acquired infection, suggesting more virulence. 相似文献