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1.
Over the past 10 years, arteriography has become a well-established technique for the diagnosis of acute lower gastrointestinal bleeding, but not particularly for rectal bleeding. However, to the authors' knowledge, the technique of middle hemorrhoidal artery embolization has rarely been reported in the literature. In the present report, three patients with life-threatening rectal bleeding are presented, which was controlled by superselective embolization of the middle hemorrhoidal artery or selective embolization of the internal iliac artery as a last resort.  相似文献   
2.
The organophosphate insecticide chlorpyrifos was irradiated under different photochemical conditions and the products characterized by gas chromatography, mass spectrometry, and NMR spectroscopy. Irradiation of chlorpyrifos in hexane yielded dechlorinated photoproducts and cleavage products. In methanol, besides these products, chlorpyrifos gave oxons. Several new photoproducts, the formation of which apparently occurs by the displacement of 5-chloro by a methoxy substituent in the pyridyl moiety. The possibility of formation of such products on glass, soil, and leaf surfaces under the influence of UV and solar simulated light have also been explored and many new products presumably formed due to simultaneous photo-dechlorination, oxidation and hydrolytic processes were detected. Photodegradation of chlorpyrifos was rapid on a soil surface but comparatively slow on glass and leaf surfaces.Contribution No. 344  相似文献   
3.
Experimental infection of golden hamsters with the hookworm, Ancylostoma ceylanicum, caused a profound decline in the hepatic microsomal cytochrome P450 content. Concomitant decrease was also noticed in aminopyrine N-demethylase and benzo[a]pyrene hydroxylase activities. However, aniline hydroxylase activity was only marginally elevated during the infection. Microsomal markers, viz., cytochrome b5, NADH-cytochrome-c reductase, and glucose-6-phosphatase, were not significantly altered. Hepatic tissue exhibited an accumulation of lipids, especially phospholipids, triglycerides, and cholesterol, resulting in fatty necrosis around the central vein region. Isolated hepatic microsomes showed a decrease in phosphatidylcholine content. Impairment in hepatic mixed function oxidase (MFO) activities was further confirmed by prolongation in hexobarbital sleeping time and zoxazolamine-induced paralysis. The hepatic MFO system of A. ceylanicum-infected hamsters responded qualitatively and quantitatively in a manner similar to that of control hamsters, upon stimulation with selective chemical inducers like phenobarbitone and 3-methylcholanthrene. Kinetic and in vitro substrate binding studies revealed that for aminopyrine the substrate affinity and the maximum enzyme activity (Vmax) were decreased, while for aniline the binding affinity was decreased and the binding capacity was enhanced. Results indicate specific/selective impairment of the hepatic microsomal cytochrome P450 system during hookworm infection and may have many practical implications in toxicology and pharmacology.  相似文献   
4.
Eight fresh-frozen cadaver knees were studied to evaluate whether an isometrically placed posterior cruciate ligament (PCL) graft restores normal posterior tibial translation without overconstraining anterior tibial translation. Each knee was tested with a three-axis load cell in the intact state, after PCL sectioning, and after PCL reconstruction. After PCL reconstruction, posterior tibial displacement was restored to values observed in the intact state for all flexion angles except 60 degrees and 90 degrees. Anterior tibial translation was not significantly changed for any of the three states. These results indicate isometric reconstruction of the PCL significantly reduces posterior tibial translation without overconstraining anterior tibial translation.  相似文献   
5.

Background

The relationship between traffic-related air pollution (TRAP) and risk factors for cardiovascular disease needs to be better understood in order to address the adverse impact of air pollution on human health.

Objective

We examined associations between roadway proximity and traffic exposure zones, as markers of TRAP exposure, and metabolic biomarkers for cardiovascular disease risk in a cohort of patients undergoing cardiac catheterization.

Methods

We performed a cross-sectional study of 2,124 individuals residing in North Carolina (USA). Roadway proximity was assessed via distance to primary and secondary roadways, and we used residence in traffic exposure zones (TEZs) as a proxy for TRAP. Two categories of metabolic outcomes were studied: measures associated with glucose control, and measures associated with lipid metabolism. Statistical models were adjusted for race, sex, smoking, body mass index, and socioeconomic status (SES).

Results

An interquartile-range (990 m) decrease in distance to roadways was associated with higher fasting plasma glucose (β = 2.17 mg/dL; 95% CI: –0.24, 4.59), and the association appeared to be limited to women (β = 5.16 mg/dL; 95% CI: 1.48, 8.84 compared with β = 0.14 mg/dL; 95% CI: –3.04, 3.33 in men). Residence in TEZ 5 (high-speed traffic) and TEZ 6 (stop-and-go traffic), the two traffic zones assumed to have the highest levels of TRAP, was positively associated with high-density lipoprotein cholesterol (HDL-C; β = 8.36; 95% CI: –0.15, 16.9 and β = 5.98; 95% CI: –3.96, 15.9, for TEZ 5 and 6, respectively).

Conclusion

Proxy measures of TRAP exposure were associated with intermediate metabolic traits associated with cardiovascular disease, including fasting plasma glucose and possibly HDL-C.

Citation

Ward-Caviness CK, Kraus WE, Blach C, Haynes CS, Dowdy E, Miranda ML, Devlin RB, Diaz-Sanchez D, Cascio WE, Mukerjee S, Stallings C, Smith LA, Gregory SG, Shah SH, Hauser ER, Neas LM. 2015. Association of roadway proximity with fasting plasma glucose and metabolic risk factors for cardiovascular disease in a cross-sectional study of cardiac catheterization patients. Environ Health Perspect 123:1007–1014; http://dx.doi.org/10.1289/ehp.1306980  相似文献   
6.
OBJECTIVES: In scleroderma, outcome measures such as skin score provide only limited information about the functional impact of the disease. The requirement for validated and convenient instruments that reliably reflect disease morbidity is now recognized. This study compares the Disability Index of the Health Assessment Questionnaire (HAQ-DI) with two more recently developed scleroderma-specific tools: scleroderma-visual analogue scales (scleroderma-VAS) and the UK scleroderma Functional Score (UKFS). In addition, the use of clinical and laboratory measures as predictors of disease severity have been examined. METHODS: One hundred and fifteen consecutive patients were studied. Subjects completed the 20-item HAQ-DI, the scleroderma-VAS and a questionnaire related to hand and muscle function (UKFS). Clinical details, measurement of maximal hand-spread, fist-closure and investigations for internal organ involvement were recorded. RESULTS: Over 68% of patients with diffuse disease had moderate to severe disease on the UKFS, compared with 44% with limited disease. The mean UKFS in diffuse disease was 14.7 (s.d. 9.1) and 10.6 (s.d. 8.5) in the limited subset (P=0.02). The mean HAQ-DI in diffuse disease was 1.23 (s.d. 0.77) and 0.79 (s.d. 0.75) in the limited subset (P=0.005). The HAQ-DI showed significant correlation with UKFS (r=0.9; P < 0.001). Several clinical and laboratory measures were associated with higher HAQ-DI and UKFS. CONCLUSIONS: This is the first comparative study of the UKFS and the HAQ-DI. These data show a strong correlation between assessment methods. Higher scores correlated with clinical and laboratory indicators of severe disease. Used together, these inexpensive tools assess general and organ-specific symptoms, as well as functional limitation.  相似文献   
7.
A micromethod adapted for automated determinations was used to measure basal plasma levels of homocyst(e)ine [H(e)]. These levels included the sum of free and bound forms of homocysteine, its disulfide oxidation product, homocystine, and the homocysteine-cysteine-mixed disulfide. Two groups of subjects were studied: apparently healthy individuals (n = 103) and patients with peripheral arterial occlusive disease (PAOD) (n = 47). Because age in PAOD patients was higher than in control subjects, the control subjects were subdivided into younger and older groups (aged 60 years or less and more than 60 years, respectively). The H(e) levels in the younger groups were 11.18 +/- 3.58 (mean +/- SD, expressed as homocysteine) and 8.58 +/- 2.82 nmol/ml in men and women, respectively; in the older groups, the levels were 10.74 +/- 2.16 and 9.04 +/- 2.16 nmol/ml in men and women, respectively. There was a positive correlation of H(e) levels with age in the younger control women (r = 0.373; p less than 0.02); no significant correlations were present in the other three control groups. Levels of H(e) in PAOD patients (15.44 +/- 5.76 and 17.04 +/- 8.26 nmol/ml in men and women, respectively) were significantly higher than those indicated above in the older controls. Next, the PAOD patients were assigned to two subgroups: 1) those with normal levels of H(e) (within two standard deviations of the mean of the control values) and 2) those with elevated levels of H(e). Age, cholesterolemia, and the prevalence of smoking and diabetes were similar in both subgroups. These results suggest that elevated plasma H(e) is an independent risk factor for arterial occlusive disease.  相似文献   
8.

Objective

Recent hypertension guidelines recommend initiation of treatment with a fixed dose combination of two drugs for more effective and quicker blood pressure control. Few of these have been assessed for efficacy and acceptability. This study examines the short term blood pressure control and acceptability of perindopril, with or without its fixed dose combinations (FDC) with amlodipine and Indapamide in younger patients.

Methods

In a multicentre prospective observational study, patients with stage 1 hypertension were prescribed perindopril 4 mg per day. Those with stage 2 or 3 hypertension were prescribed a single tablet per day of 4 mg perindopril and 5 mg amlodipine (COVERSYL AM), or 4 mg perindopril and 1.25 mg indapamide (COVERSYL PLUS)for 45 days. The primary outcomes were the frequency of patients achieving blood pressure control and the adverse effect of pedal edema.

Results

Of 426 patients, with a mean age of 45 years, distributed throughout India, and an average (SD) baseline systolic/diastolic blood pressure of 157.2 (13.5)/98.6 (7.4), 303 (71.1%) achieved blood pressure control. Mean (SD) SBP/DBP decreased from baseline by 26.9 (12.6), and DBP by 15.4 (7.2) mm Hg. Few patients discontinued treatment, and the frequency of cough that interfered with sleep and ankle edema was low.

Conclusion

In patients requiring combination antihypertensive treatment, the regimen of perindopril alone or its FDC with Indapamide or amlodipine reduces blood pressure effectively, resulting in high rates of blood pressure control over the short term, with a low frequency of side effects including cough and pedal edema.  相似文献   
9.
10.
This study compared the relative isolation rate of Group B Streptococcus (GBS) from 663 low vaginal swabs, collected from antenatal patients, on three media: horse blood agar plus neomycin (75 mg/l) (Neo), Islam agar (Islam) and Islam agar plus nalidixic acid (15 mg/l) and colistin sulphate (10 mg/l) (Islam Plus). One hundred and forty-seven (22%) GBS were isolated. At 24 hours the isolation rate was highest using Neo, but within 72 hours there was little difference. The isolation rates for Neo, Islam and Islam Plus at 24 hours were 124 (18.7%), 103 (15.6%), 109 (16.4%) (P < 0.05); at 48 hours 125 (18.9%), 116 (17.5%), 121 (18.1%) (P > 0.1); and at 72 hours 125 (18.9%), 121 (18.3%) and 127 (19.1%) (P > 0.1), respectively. Twenty-two isolates were missed on Neo, 26 on Islam and 20 on Islam Plus. Of those missed on Islam agars, 12 failed to produce pigment and were only detected on Neo. The disadvantage of Neo is the need to perform additional tests to confirm the identity as GBS. In the present study 100 suspicious colonies were identified as Group D.  相似文献   
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