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161.
BACKGROUND: A study of Asian-American students suggested a positive association between inactive ALDH2*2 and susceptibility to hangover. A biomarker for moderate-to-heavy drinking in persons with inactive aldehyde dehydrogenase-2 (ALDH2) is increased mean corpuscular volume (MCV). METHODS: Associations between hangover and ALDH2 genotype, alcohol flushing, and MCV were examined for 251 Japanese workers (139 men, 112 women). RESULTS: Inactive ALDH2*1/2*2 heterozygotes drank less alcohol than active ALDH2*1/2*1 homozygotes (p < 0.0001), but the frequency of hangover did not significantly differ between the two groups for either gender. The amount of drinking reported to lead to hangover was significantly less for male and female ALDH2*1/2*2 heterozygotes than for their ALDH2*1/2*1 homozygous counterparts (p < 0.005). The proportion of men who had hangover three times or more during the past year increased significantly with increased daily alcohol consumption in men with the ALDH2*1/2*2 genotype (p = 0.0002) but not in those with the ALDH2*1/2*1 genotype. For men who usually consumed <44 g of ethanol/day, the median amount of drinking before hangover was significantly lower for ALDH2*1/2*2 men than for ALDH2*1/2*1 men reporting the same level of consumption. Hangover occurred with consistently high frequency among ALDH2*1/2*1 men, regardless of their daily consumption. Similar findings were observed in a comparison of men who never flushed and those who reported current or former flushing, a surrogate marker of inactive ALDH2. Assessment of hangover risk by quartiles of MCV showed that men with MCV of > or =96 had a significantly higher risk of hangover than did men with MCV of <91 (odds ratio = 5.56; 95% confidence interval = 1.69-18.25). CONCLUSIONS: Inactive heterozygous ALDH2, alcohol flushing, and increased MCV were positively associated with hangover susceptibility in Japanese workers, suggesting that acetaldehyde is etiologically linked to the development of hangover.  相似文献   
162.
This study evaluated how tube potential-filter combinations [with a molybdenum (Mo) anode and either an Mo or a rhodium (Rh) filter] influence image quality and radiation dose to breasts of different thicknesses in film-screen mammography using a new mammography phantom (CDMAM Phantom Type 3.4). A 28-kVp/Mo tube potential-filter combination is recommended for a breast (phantom) thickness of 40 mm or less, 28 kVp/Rh for a breast (phantom) thickness of 60 mm or less, and 30 kVp/Rh for a breast (phantom) thickness greater than 60 mm.  相似文献   
163.
Succinyl-CoA:3-ketoacid CoA transferase (SCOT; locus symbol OXCT; E.C. 2.8.3.5) is the main determinant of the ketolytic capacity of tissues. Hereditary SCOT deficiency causes episodic ketoacidosis. Permanent ketosis has been regarded as a pathognomonic feature of SCOT deficiency. There are three SCOT-deficient patients from a small region in Japan and they have not manifested permanent ketosis, even though their ketoacidotic crises were as severe as those of other SCOT-deficient patients. All three were homozygous for the T435N mutation. Transient expression analysis of wild-type and mutant cDNA showed that the T435N mutant retained significant residual SCOT activities (20% for that of the wild-type at 39.5 degrees C, 25% at 37 degrees C, and 50% at 30 degrees C). The difference of residual SCOT activities at these temperatures in expression analyses was due to differences in the level of the mutant protein. SCOT activity of the T435N protein was more vulnerable than the wild-type to heat treatment at 42 degrees C and 55 degrees C. These temperature-sensitive characteristics of the mutant protein may explain, in part, why the patients developed ketoacidotic crises during febrile illness. In SCOT-deficient patients retaining some residual activity, permanent ketosis may be absent.  相似文献   
164.
OBJECTIVE: To investigate the relationship between unexplained infertility and fertilization failure from nucleoprotein defects in ejaculated human sperm and to study the usefulness of sperm chromatin assays, using AO fluorescence dye, to evaluate patients with unexplained infertility before treatment. STUDY DESIGN: From January 1999 to January 2000, 513 infertile couples had the clinical causes of their infertility assessed. During the next investigative period (February 2000-February 2001), 137 cases of unexplained infertility (n = 80) were chosen for this study, as were cases of tubal factor infertility (n = 57) as controls. The status of nuclear chromatin in ejaculated sperm was examined using acridine orange staining, followed by a conventional in vitro fertilization procedure. RESULTS: The number of patients with immature ejaculated sperm was 16 of 30 (53.3%) unexplained infertility cases involving fertilization failure, 8 of 50 (16.0%) unexplained infertility cases without fertilization failure and 5 of 57 (8.8%) tubal factor infertility cases. A significant difference was observed between unexplained infertility cases with fertilization failure and the other groups (P < .0001). CONCLUSION: These results suggest that the nuclear immaturity of ejaculated human sperm may be 1 of the primary factors underlying unexplained infertility.  相似文献   
165.
This study confirms the presence of a novel variable number of tandem repeats polymorphism, designated as HumDN1, in intron 4 of the human deoxyribonuclease I (DNase I) gene. Genotyping was performed without difficulty by PCR-amplification and separation by agarose gel electrophoresis in 423 Japanese, originating from four geographically diverse areas in Japan, and 89 Germans. The HumDN1 allele variability was due to different numbers of 56-bp repeat sequences, and five different alleles were distinguished with apparent size between 364 and 588 bp. Although there was a general uniformity for the polymorphism in the Japanese population, significant differences in genotype distribution were found between the Japanese and German populations. Furthermore, linkage disequilibrium between the HumDN1 and DNase I protein polymorphisms was revealed.  相似文献   
166.
To evaluate the clinical usefulness of power Doppler imaging (PDI), we compared this method to gray-scale transrectal ultrasound (TRUS) in the detection of prostate cancer. A total of 101 men with abnormally high serum prostate specific antigen (PSA) levels and/or abnormal digital rectal examination (DRE) findings were assessed using TRUS and PDI. Random systematic sextant and bilateral far lateral prostate biopsies were performed in all cases. In addition, when TRUS revealed a hypoechoic lesion or PDI revealed a hypervascular lesion (HVL), these lesions were directly biopsied. Of the 101 patients, 48 (47.5%), 42 (41.5%) and 42 (41.5%) were suspicious of having prostate cancer by DRE, TRUS and PDI, respectively. Prostate needle biopsy revealed prostate cancer in 39 patients (38.6%) and benign prostatic diseases in 62 patients (61.4%). If prostate needle biopsy was avoided when PDI was negative, then PDI eliminated the need for biopsy in 59 of the 101 patients (rate of biopsy procedures saved: 58.4%) and missed only 8 (13.6%) prostate cancers. Moreover, in 63 patients with intermediate PSA (3-10 ng/ml), the rate of biopsy procedures saved by DRE, TRUS, and PDI was 60.3%, 65.1%, and 68.3%, respectively, and the rate of cancers missed was 26.3%, 19.5%, and 14.0%, respectively. In a total of 826 specimens of TRUS-guided prostate biopsy, 126 (15.3%) specimens had adenocarcinoma. Site by site based analysis of the present series revealed 34.1% of prostate cancer sites were isoechoic and hypervascular. On a site by site basis, PDI had better sensitivity, specificity, positive predictive value and negative predictive value than TRUS. In 48 patients without abnormal DRE findings, on a site by site basis, the sensitivities of TRUS and PDI were 22.9% and 34.4%, respectively. Gleason score was associated with a positive rate of PDI on both a patient basis and site by site basis. From these results, on a patient basis, we conclude that PDI was helpful in the indication for prostate biopsy for all patients or patients with intermediate PSA level. On a site by site basis, PDI may be able to select prostate cancer sites at biopsy, in particular in patients without abnormal DRE findings.  相似文献   
167.
An 82-year-old woman underwent right hemicolectomy by median laparotomy. Two weeks later, a pulsatile mass was found at the left side of the surgical wound, which was diagnosed as pseudoaneurysm of the inferior epigastric artery by color Doppler US and CT. The pseudoaneurysm was successfully treated by US-guided compression of the neck of the aneurysm for 30 minutes. US-guided compression should be considered the treatment of choice for postsurgical pseudoaneurysm of the inferior epigastric artery. (Present address of author has been changed.)  相似文献   
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170.
Antipsychotic polypharmacy has been empirically used and a recent trend in favour of that mode of therapy has been suggested for the treatment of schizophrenia. The clinical efficacy, however, still remains to be clarified. In order to critically evaluate the usefulness of such kind of psychopharmacotherapy, antipsychotic combination regimen (polypharmacy) was switched to a treatment with the single main antipsychotic (monotherapy) in cross-tapered fashion, while approximately maintaining the total amount, for patients with chronic schizophrenia. Patients had been treated with an average of three antipsychotics and maintained with the same antipsychotic polypharmacy regimen for more than 6 months before the entry. They were followed up with an antipsychotic monopharmacy and evaluated at 24 wk after completion of switching. Forty-seven patients were recruited for this study. Of 44 patients for whom evaluation was possible, 24 (54.5%) remained stable, while 10 (22.7%) showed improvement and the same number of patients ended in a deleterious status. Twenty-two patients were converted to antipsychotic monotherapy, while another 12 needed minimal dosing of low-potency agents. Overall, social functioning, evaluated by the Global Assessment of Functioning and the Clinical Global Impression, remained unchanged. Eighteen of 34 successful patients showed adverse effects of the main antipsychotic medication, which necessitated a significant dose reduction. Nine out of 10 deteriorating patients had been treated with a combination of low- and high-potency antipsychotics. It is suggested that many instances of antipsychotic polypharmacy is avoidable. The result is compatible with the current treatment recommendations, which dictate the use of a single antipsychotic agent.  相似文献   
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