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991.
The purpose of this study was to differentiate by means of electrophysiologic study, a drug's ability to terminate or to prevent ventricular tachycardia (VT). Differences between the 2 effects were examined in patients with VT and the underlying mechanisms were studied in verapamil-responsive idiopathic sustained VT. The clinical significance of the distinction for chronic oral drug therapy is discussed.

Thirty-five cases of inducible sustained VT were studied. A drug was considered “preventative” if it prevented VT induction and repetitive ventricular response, and “terminating” if it stopped induced VT within 15 complexes or could stop VT after its intravenous administration.

Prevention and termination occurred together in 13 of 19 cases (68%) with disopyramide, in 10 of 19 cases (53%) with procainamide, in 8 of 12 cases (67%) with lidocaine, in 11 of 15 cases (73%) with mexiledne, and in 10 of 16 cases (63%) with verapamil. In the 16 in which verapamil terminated VT, VT rate immediately before termination slowed markedly from 167 ± 33 to 134 ± 28 beats/min. In the 6 cases without preventative effects, minimal and maximal premature intervals for VT induction increased significantly, from 291 ± 70 to 335 ± 85 ms and 323 ± 68 to 423 ± 109 ms, respectively, after verapamil administration.

In 2 cases in which verapamil had a terminating effect, 5 mg of verapamil restored sinus rhythm but 10 mg caused premature beats resembling VT complexes. In another 2, 5 mg of verapamil lengthened the minimal premature interval; 10 mg increased both minimal and maximal premature intervals and lengthened the VT cycle.

The chronic oral aukninistration of verapamil resulted in disappearance of VT attacks in 2 of 4 patients and a decrease in both their number and duration in 2 of 4 patients in whom both termination and prevention were seen in the electrophysiologic study. However, in 4 patients who had only termination, the VT episodes remained unchanged in 2 and even increased in the other 2.  相似文献   

992.
Acquired idiopathic generalized anhidrosis (AIGA) is characterized by an acquired impairment in total body sweating despite exposure to heat or exercise. Severe cases may result in heatstroke. Most cases of AIGA have been reported in Asia, especially in Japan. However, there is limited information on the epidemiology of this condition, and no diagnostic criteria or appropriate treatment options have been established. This guideline was developed to fill this gap. It contains information on the etiology, diagnosis, evaluation of disease severity and evidence‐based recommendations for the treatment of AIGA. Appropriate treatment according to disease severity may relieve the clinical manifestations and emotional distress experienced by patients with AIGA.  相似文献   
993.

Background

MicroRNA levels in sera or hair may potentially be useful biomarkers for various diseases. The diagnosis of nail diseases is sometimes difficult, and nail psoriasis without skin lesions is indistinguishable from nail changes caused by other diseases.

Objectives

We evaluated nail microRNA levels as biomarkers for the diagnosis of psoriasis patients.

Materials & methods

MicroRNA levels were examined in psoriasis patients with (11 patients) and without (six patients) nail changes. Normal control nails were collected from 17 healthy subjects. Eight patients with other diseases who also had nail changes were also included as disease controls.

Results

Microarray, real-time PCR, and in situ hybridisation indicated that the expression levels of nail miR- 4454 were decreased in psoriasis patients with nail changes, compared to those patients with other diseases involving nail change, or healthy subjects. The miR-4454 levels in nails showed a significant inverse correlation with the Nail Psoriasis Severity Index (NAPSI) score, suggesting that nail miR-4454 levels reflect nail condition.

Conclusion

The levels of microRNAs in nails may be suitable biomarkers for diagnosis or evaluation of disease activity of psoriasis.
  相似文献   
994.
995.
A high total homocysteine (tHcy) level during pregnancy is a risk factor for adverse perinatal outcomes, such as fetal growth restriction and preeclampsia. Caffeine is assumed to increase tHcy levels by acting as a vitamin B6 antagonist. The objective of this study was to examine a relationship between circulating tHcy levels and dietary caffeine and vitamin B6 intakes in pregnant Japanese women. A total of 321 healthy women with singleton pregnancies were recruited in metropolitan Tokyo, from June to December 2008, resulting in the final number included in the study as 254. Dietary caffeine intakes did not correlate with plasma tHcy levels. When we analyzed the data according to caffeinated beverages, caffeinated tea consumption was positively associated with plasma tHcy levels only among the women with a high intake of vitamin B6, after controlling for confounding factors (P = 0.029). No correlation between coffee consumption and plasma tHcy levels was found. Pregnant Japanese women might need to cut down the consumption of caffeinated tea as well as take sufficient vitamin B6 in order to prevent the tHcy levels from increasing.  相似文献   
996.
The spread of antimicrobial-resistant Neisseria gonorrhoeae worldwide is a critical issue in the control of sexually transmitted infections. The purpose of this study was to clarify recent trends in the susceptibility of N. gonorrhoeae to various antimicrobial agents and to compare these data with our previous data. Minimum inhibitory concentrations (MICs) of various antimicrobial agents were determined in N. gonorrhoeae strains clinically isolated from male gonococcal urethritis. In addition, amino acid sequencing of penicillin-binding protein (PBP) 2, encoded by the penA gene, was analyzed so that genetic analysis of mosaic PBP 2 could clarify the susceptibility of the strains to cefixime and other cephalosporins. The susceptibility rate for ceftriaxone, cefodizime, and spectinomycin, agents whose use is recommended by the guideline of the Japanese Society of Sexually Transmitted Infections (JSSTI), was 100 %. The susceptibility rates of the strains to penicillin G and ciprofloxacin were lower than those in previous reports. Mosaic PBP 2 structures were detected in 51.9 % of the strains and the MICs of the strains with the mosaic PBP 2 to cefixime were much higher than those of the strains without the mosaic PBP 2. In the clinical situation, the treatment regimen recommended by the JSSTI remains appropriate; however, the susceptibility to cephalosporins should be intensively surveyed because strains with mosaic PBP 2 were commonly detected.  相似文献   
997.
Ruptured vertebrobasilar dissecting aneurysm is usually treated surgically because rebleeding negatively affects outcome. However, the risk of rebleeding decreases markedly once several hours have passed from the initial bleeding. Moreover, surgery-related complications are not rare. We describe seven patients with ruptured vertebrobasilar dissecting aneurysm. To prevent rebleeding during the acute stage, we treated all seven patients conservatively with fentanyl instead of emergency surgery. During the follow-up period (mean 20 months), no patient suffered rebleeding. Conservative treatment with fentanyl administration may be a good option for management of ruptured vertebrobasilar dissecting aneurysm during the acute stage.  相似文献   
998.
999.

Background

To diagnose sputum smear-negative pulmonary tuberculosis (PTB) is difficult and the ability of high-resolution computed tomography (HRCT) for diagnosing PTB has remained unclear in the sputum smear-negative setting. We retrospectively investigated whether or not this imaging modality can predict risk for sputum smear-negative PTB.

Methods

We used HRCT to examine the findings of 116 patients with suspected PTB despite negative sputum smears for acid-fast bacilli (AFB). We investigated their clinical features and HRCT-findings to predict the risk for PTB by multivariate analysis and a combination of HRCT findings by stepwise regression analysis. We then designed provisional HRCT diagnostic criteria based on these results to rank the risk of PTB and blinded observers assessed the validity and reliability of these criteria.

Results

A positive tuberculin skin test alone among clinical laboratory findings was significantly associated with an increase of risk of PTB. Multivariate regression analysis showed that large nodules, tree-in-bud appearance, lobular consolidation and the main lesion being located in S1, S2, and S6 were significantly associated with an increased risk of PTB. Stepwise regression analysis showed that coexistence of the above 4 factors was most significantly associated with an increase in the risk for PTB. Ranking of the results using our HRCT diagnostic criteria by blinded observers revealed good utility and agreement for predicting PTB risk.

Conclusions

Even in the sputum smear-negative setting, HRCT can predict the risk of PTB with good reproducibility and can select patients having a high probability of PTB.  相似文献   
1000.
Patients with mild cognitive impairment (MCI) represent a risk population for progressing to dementia of the Alzheimer type (DAT). However, clinical criteria do not ensure reliable individual prognosis in these patients. The objective of this longitudinal, prospective study was to examine the value of (18)F-FDG PET of cerebral glucose metabolism and of genetic susceptibility, as defined by an APOEepsilon4-positive genotype, with regard to the early diagnosis of DAT in patients with MCI. METHODS: In 30 patients with the diagnosis of MCI (16 female, 14 male; age, 70 +/- 8 y), baseline and follow-up examinations (mean observation period, 16 mo) were performed. In all patients, the APOE genotype was assessed and cerebral glucose metabolism was evaluated at baseline using cranial (18)F-FDG PET. Individual PET data were screened for findings suggestive of Alzheimer's disease (AD), with the help of an automated computer program. After stereotactical normalization of the PET images, this program performs an observer-independent statistical comparison with an age-matched reference database (n = 22). RESULTS: In 43% of all MCI subjects, a PET scan suggestive of AD pathology according to our predefined criteria was observed at baseline (PET+); 57% of all MCI patients were carriers of the APOE epsilon4 allele (e4+). In 40% of all patients, progression of symptoms within the observation period justified the clinical diagnosis of probable DAT at the time of follow-up reevaluation. Statistical evaluation revealed the best results for PET with regard to early diagnosis of DAT in MCI patients (sensitivity, 92%; specificity, 89%). Classification according to the APOE genotype was significantly less successful (sensitivity, 75%; specificity, 56%). However, a combination of both diagnostic tests allowed early diagnosis with either very high specificity (PET+ AND e4+: sensitivity, 67%; specificity, 100%) or very high sensitivity (PET+ OR e4+: sensitivity, 100%; specificity, 44%). CONCLUSION: (18)F-FDG PET of cerebral glucose metabolism is a valuable diagnostic tool for the prediction of clinical outcome in individual MCI patients. Results are superior to the exclusive assessment of the APOE genotype. A combination of both functional imaging and genotyping may allow an early high-risk or low-risk stratification of patients with either very high sensitivity or very high specificity. This may be valuable, for example, for patient selection in scientific studies.  相似文献   
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