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At least 289 records · Page 16Linked to original sources
PubMed1997

Cesarean delivery. Microbial colonization in amniotic fluid.

OBJECTIVE: To determine the frequency, clinical significance and causative factors behind intraamniotic microbial colonization in uninfected parturients at the time of cesarean delivery. STUDY DESIGN: Amniotic fluid specimens for bacterial and mycoplasmal cultures were obtained by direct aspiration at cesarean section from 251 pregnant women (24-43 completed weeks) who had no clinical infection at the time of the operation. The symptoms of maternal infection were followed postoperatively for the first week of the puerperium. RESULTS: The prevalence of amniotic fluid microbial invasion was 29% (72/251). In patients not in labor and with intact membranes, it was 13% (20/158); in patients in labor and with intact membranes, 23% (5/22); and in those with ruptured membranes, 66% (47/71). The most common species isolated were Ureaplasma urealyticum, Lactobacillus species and coagulase-negative staphylococci. In the total 251 patients, clinically evident postoperative endometritis was observed in 6 (2%) and wound infection in 10 (4%). In patients operated on and with intact membranes, no risk factors were found as regards amniotic fluid microbial colonization. In patients operated on after rupture of the membranes, the only significant risk factor as regards amniotic fluid microbial invasion was use of an internal monitor before the operation (P < .0003) (relative risk 10.7, 95% confidence limit 2.9-39.4). The relative risk of postoperative endometritis was 2.3 (95% confidence limit 1.3-4.3) in patients with microbial invasion of the amniotic cavity as compared to patients without invasion. The corresponding risk value for post-operative wound infection was 1.4 (95% confidence limit 0.6-3.1). CONCLUSION: Though the incidence of microbial invasion of the amniotic fluid before surgery was unexpectedly high, its clinical significance as regards maternal puerperal morbidity appeared to be low. The use of internal monitoring during labor was the only significant risk factor as regards amniotic fluid microbial colonization in patients operated on after membrane rupture.

Amniotic Fluid↗
PubMed2003

Relation between vesicular eruptions on the hands and tinea pedis, atopic dermatitis and nickel allergy.

The aetiology of vesicular eruptions on the palms and on the sides of the fingers (pompholyx) is unclear. The present study was undertaken to establish whether tinea pedis, atopic dermatitis or nickel allergy is a risk factor for development of vesicular eruptions. Three-hundred-and-ninety-eight individuals (included from an ongoing population study on hand eczema in twins) were included. A history of previous hand eczema and atopic dermatitis was taken, and a clinical examination including a patch test with nickel was performed. A test sample for tinea pedis was taken from the fourth interdigital space on the right foot. The relative risk for vesicular eruptions present in individuals with tinea pedis was 3.58 (confidence limits 1.19-10.82, p < 0.05). For individuals with atopic dermatitis, relative risk was 1.44 (confidence limits 0.34-6.07, n.s.) and for those with nickel allergy it was 0.45 (confidence limits 0.06-3.36, n.s.). A relationship between tinea pedis and vesicular eruptions on the hands was statistically confirmed in the present study. In this part of the population study material, no association with atopic dermatitis or nickel allergy was observed.

Dermatitis, Allergic Contact↗
PubMed1988

HLA and antibiotic allergic skin eruption.

Chinese patients with cutaneous eruption due to antibiotics were found to be positively associated with HLA-BW46 (RR = 2.5; 95% confidence limit 1.2-4.9) and negatively associated with HLA-B40 (RR = 0.46; 95% confidence limit 0.22-0.98). The association with HLA-BW46 was even higher in patients with ampicillin sensitivity (RR = 3.5; 95% confidence limit 1.4-9.0).

Anti-Bacterial Agents↗
PubMed1997

Inter-observer agreement in clinical optic disc measurement using a modified 60 D lens.

PURPOSE: To assess the inter-observer agreement of the measurement of optic disc dimensions by two observers using a modified 60 dioptre (D) fundus examination lens. METHOD: The vertical disc and cup diameters of 29 eyes were measured by two independent observers using a 60 D lens modified by incorporation of a 0.1 millimetre scale graticule. The vertical cup/disc ratio was calculated. Inter-observer agreement was assessed by calculation of the inter-observer differences and by the weighted kappa statistic. RESULTS: The two observers showed good agreement for the measurement of disc diameter (mean difference -0.04; range -0.04, 0.2) and for cup diameter (mean difference -0.03; range 0.3, 0.2). Closer agreement for the vertical cup/disc ratio was achieved (mean kappa 0.96; 95% confidence limits 0.90, 1.0). The 95% confidence limit for the mean inter-observer difference in cup/disc ratio was 0.11, suggesting that a change of > 0.1 in the assessment of the cup/disc ratio by this technique is significant at the 5% level. CONCLUSION: High inter-observer agreement of optic disc measurement can be achieved with this technique. The method has the potential to improve the clinical evaluation of the optic disc and the precision and accuracy of the clinical measurement of other fundal structures.

Equipment Design↗
PubMed2002

Measurement of spinal kyphosis: implications for the management of Scheuermann's kyphosis.

STUDY DESIGN: Repeat clinical radiograph measurement of kyphosis was performed. OBJECTIVES: To evaluate precision in kyphosis measurement, the presence of intra- and interobserver error, and the effect of endplate selection and curve magnitude on error. SUMMARY OF BACKGROUND DATA: One study thus far has shown no interobserver difference in readings and an error interval of +/-11 degrees. METHODS: Four experienced examiners measured 30 radiographs of varying angles of kyphosis without preselected end vertebrae twice using the Cobb method. RESULTS: The mean intraobserver variance was 4.3 degrees (95% confidence interval, +/-9.6 degrees). One examiner had significantly better precision (P= 0.02) than the other examiners, who had no significant difference among them (P = 0.41). This examiner's mean intraobserver difference was 2.3 degrees (95% confidence limit, +/-6.2 degrees ). The 95% confidence limit for the interobserver difference was +/-8.7 degrees. The vertebral error index did not have a rank correlation with precision between readings. Magnitude of curve did not correlate with variance in measurement. CONCLUSIONS: The broad range in intra- and interobserver differences in the measurement of kyphosis should be taken into account in making management decisions or evaluating the success or failure of a treatment program. Careful technique in measurement may allow for improvement in individual precision.

Comorbidity↗
PubMed1985

Catecholamines in amniotic fluid as indicators of intrapartum fetal stress.

Catecholamines were measured in the amniotic fluid and in the first voided newborn urine obtained from appropriate-for-date infants of term deliveries. Catecholamine values in the amniotic fluid and urine were nearly equal when expressed in terms of creatinine. Significant positive correlations were observed between the amniotic fluid and urine of norepinephrine and epinephrine. In normal cases (n = 32) that underwent uneventful vaginal delivery, the 95% confidence limits for norepinephrine and epinephrine in the amniotic fluid were 1.53 to 2.33 ng/ml and 0.16 to 0.30 ng/ml, respectively. In cases of moderate stress (n = 12), only norepinephrine showed significantly higher values than the normal cases, while in cases of severe stress (n = 12), norepinephrine became more significantly high, and epinephrine was found to be elevated significantly. A significant difference was noted in the incidence of fetal stress between the infants with more than and those with less than 2.30 ng/ml of norepinephrine, the upper limits of the normal 95% confidence limits. However, for epinephrine such a significant difference was not noted. It was concluded that amniotic fluid catecholamines are of fetal origin and reflect fetal sympathoadrenal activity directly, even during labor, and that their level may be a good indicator of fetal condition and stress.

Amniotic Fluid↗
PubMed1989

Does post myocardial infarction rehabilitation prolong survival? A meta-analytic survey.

Cardiac rehabilitation undoubtedly helps post-myocardial infarction patients to feel better; however, it is under consideration whether or not it also prolongs their survival. Since 1972 several published studies have examined the role of physical rehabilitation in relation to patient survival after myocardial infarction. Eight randomized controlled trials were reviewed in order to compare the rate of events (total death, cardiac death, recurrence of non-fatal myocardial infarction) in the trained and untrained patient population. A tendency toward a positive training effect on survival was present in almost all trials; however, in only one study was the number of cardiac deaths shown to be significantly reduced in trained patients. The aim of this study was to use a quantitative analysis based on estimates of individual trials to evaluate the effect of post-myocardial infarction rehabilitation programs on survival. The analysis of pooled data revealed a significant decrease in total mortality (relative risk 0.68 with 95% confidence limits 0.53-0.86; p = 0.002), and cardiac mortality (relative risk 0.62 with 95% confidence limits 0.48-0.82; p less than 0.001). However, there was a non-significant increase in recurrences (relative risk 1.12 with 95% confidence limits 0.84-1.49; p = 0.45). These data are very similar to those found by another meta-analytic survey performed on a different set of published studies, i.e., odds risk for total death 0.76, for cardiac mortality 0.75 and for non-fatal myocardial infarction 1.15.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed2002

Sampling variability of the Kunst-Mackenbach relative index of inequality.

STUDY OBJECTIVE: To derive methods of calculating confidence limits for the relative index of inequality, defined by Kunst and Mackenbach as a measure of the influence of socioeconomic status on an adverse health index, such as mortality rate. The methods may be used for a health outcome recorded on a continuous scale, as a Poisson count or as a binomial variable. RESULTS AND CONCLUSION: The confidence limits depend on the sampling variability of both the mean mortality rate and the slope of the regression line of mortality on the socioeconomic status scale variable. The best method for a continuous health outcome is based on Fieller's theorem but a good approximation is obtained by substituting the confidence limits for the slope of the regression line into the formula for the calculation of the index, or by using the variance of the logarithmic transform of the index. The last method is the most appropriate for the construction of significance tests comparing indices. The mortality rates may show statistically significant departure from linearity, while not suggesting that a linear relation is inappropriate, and the main decision is whether to base the confidence limits on the conventional standard error of the slope derived from the regression analysis or whether to use the standard deviation of the estimates of mortality rates.

Age Distribution↗
PubMed1990

Golytely preparation for colonoscopy: 1.5 liters is enough for outpatients.

In a prospective double-blind study of the effectiveness and patient acceptance of Golytely whole-gut preparation for colonoscopy, 50 consecutive patients were randomly allocated to drink either 1.5 l (Group I) or 3 l (Group II). The patients had some slight dietary restrictions, and received mild laxatives on the preceding day. The cleansing result did not differ significantly in the two groups. The result was assessed as "good" in 76% of cases in Group I (95% confidence limits 55-91%) and in 83% of cases in Group II (95% confidence limits 63-95%). In half of the remaining cases in both groups the result was "acceptable" and in the other half "poor". Patient acceptance did not differ significantly in the two groups. After completion of the randomized study, oral cleansing with 1.5 l Golytely has been our daily routine. In 42 patients so treated quality of cleansing was good in 81% (95% confidence limits 66-91%), acceptable in 12%, and poor in 7%.

Adult↗
PubMed2003

Reproducibility of quantitative dynamic contrast-enhanced MRI in newly presenting glioma.

We have investigated the reproducibility of dynamic contrast enhanced imaging techniques in nine patients with cerebral glioma. Patients were imaged twice with a 2 day interval between scans. Maps were produced of the time taken to achieve 90% enhancement (T90), the maximal intensity change per time interval ratio (MITR), the volume transfer coefficient between plasma and the extravascular extracellular space (K(trans)) and the extravascular extracellular contrast distribution volume, v(e). Measurements of K(trans) greater than 1.2 min(-1) were used to exclude pixels where first pass perfusion effects dominated the measurement. Measures of the test-retest coefficient of variation (CoV) and intraclass correlation coefficients were used to assess reproducibility for measurements from a volume of interest containing enhancing tissue from the whole tumour. MITR showed poor reproducibility (mean CoV 17.9%, 95% confidence limits for group comparisons 20.2%). T90 showed good reproducibility (mean CoV 7.1%, 95% confidence limits for group comparisons 5.2%). Calculated values of K(trans) and v(e) also showed good reproducibility (mean CoV 7.7% and 6.2% respectively, 95% confidence limits for group comparisons 6.2% and 4.8%, respectively). We conclude that the measurements of K(trans) and v(e) derived from pharmacokinetic analysis are sufficiently reproducible to support their use as a biological markers in therapeutic trials.

Aged↗
PubMed1993

Long-term results of mitral commissurotomy.

Between January 1968 and December 1989, 280 patients underwent conservative surgical treatment for pure mitral stenosis. Closed commissurotomy was utilized in 134 patients, with a mean age of 38 +/- 11 years and a mean valve area of 1.0 +/- 0.29 cm2. Open commissurotomy was performed in 146 older patients (mean age 44 +/- 11 years) with a mean valve area of 0.9 +/- 0.3 cm2. The perioperative mortality was 3% in closed procedures and 3.4% in open procedures. Surviving patients were evaluated by questionnaires or phone interviews, and 129 patients were examined by two-dimensional echocardiography with the purpose of analyzing long-term results. Follow-up was 95% complete (Grunkemeier-Starr method), with a median of 18 years in patients with closed commissurotomy and 6.6 years in patients with open commissurotomy. The actuarial survival at 21 years was 60.8% (70% confidence limits 55% to 66%) in patients having closed commissurotomies and 60.6% (70% confidence limits 49% to 71%) at 22 years in patients having open commissurotomies. The "effective palliation" rate, defined by clinical and echocardiographic criteria, was 47% at 15 years and 15% at 20 years. We conclude that mitral commissurotomy is the procedure of choice in pure mitral valve stenosis and should be applied early. When performed in patients aged less than 40 years, a 78% (70% confidence limits 72% to 84%) survival at 18 years and 67% "effective palliation" at 15 years were observed. The closed valvotomy results of our study support the present trend toward use of percutaneous balloon valvotomy.

Adolescent↗
PubMed1986

Hypertension and the risk of ischaemic heart disease.

The magnitude of the effect of hypertension as a risk factor for acute myocardial infarction (AMI) was estimated in 250 patients who presented with a first AMI who were aged 35-64 years (199 survivals and 51 deaths within 24 h), whose names were obtained from a community-based register of myocardial infarctions in the Hunter Region of New South Wales. The cases were matched by sex, age and residential area, and control subjects were obtained from a random population sample from the same region. A history of hypertension (odds ratio, 5.5; 95% confidence limits, 3.4 and 8.9) and treatment for hypertension (odds ratio, 4.2; 95% confidence limits, 2.5 and 7.2) were each significantly (P less than 0.0001) associated with an increased risk of AMI--persons with treated or untreated hypertension were four to five times more likely to develop AMI than were persons without hypertension. Adjustment for smoking did not affect the association between hypertension and the incidence of AMI. Cigarette smoking appears to have had less influence on the incidence of AMI (odds ratio, 1.7; 95% confidence limits, 1.1 and 2.4; P less than 0.01) than did a history of hypertension. Twenty-four per cent of the first AMIs that occurred in the study population were attributable to hypertension (after adjustment for smoking) and twenty-seven per cent were attributable to smoking (after adjustment for hypertension).

Adult↗
PubMed1992

Tetralogy of Fallot: favorable outcome of nonneonatal transatrial, transpulmonary repair.

This report describes our experience with 366 patients who had a transatrial, transpulmonary repair of tetralogy of Fallot between December 1980 and December 1991. Included in this group are patients with tetralogy of Fallot plus atrioventricular septal defect as well as patients displaying all degrees of aortic override (in the presence of subaortic ventricular septal defect and right ventricular outflow tract obstruction). Median age was 15.3 months and median weight, 12.3 kg. Of the 366 patients, 72% required a pericardial patch to reconstruct the main pulmonary artery or right ventricular outflow tract. Serious coronary anomalies were seen in 11 patients, without influencing surgical approach. There were two hospital deaths (0.5%; 70% confidence limits, 0.2% to 1.2%). Actuarial survival was 97.5% at 42 months (95% confidence limits, 95% to 99%) reflecting four late deaths over 1,129 patient-years of follow-up. Postoperative cardiac catheterization studies were performed in 61 patients at a mean follow-up interval of 23 months. Mean right ventricular/left ventricular systolic pressure ratio after repair was 0.46 (standard deviation, 0.28), and mean gradient across the right ventricular outflow tract was 15 mm Hg (standard deviation, 24 mm Hg). Actuarial freedom from reoperation for any reason has been 95% (95% confidence limits, 92% to 97%) at 5-year and 10-year follow-up. These early and medium-term results encourage us to continue with transatrial, transpulmonary repair of tetralogy of Fallot. We believe that this approach has an operative risk similar to or lower than transventricular repair, and that it will result in better preservation of right ventricular function in the long term.

Child, Preschool↗
PubMed1984

Risk factors for major salivary gland carcinoma. A case-comparison study.

The authors conducted a case-comparison chart-review study on 498 patients with histologically confirmed salivary gland carcinoma and 487 randomly selected patients registered at The University of Texas M.D. Anderson Hospital and Tumor Institute at Houston from 1960 through 1981. The study was undertaken to identify potential risk factors for salivary gland carcinoma. Univariate analysis of the data indicated a relationship with prior radiation therapy (odds ratio estimate of 6.17 with 95% confidence limits of 3.11-12.22) and with previous primary cancer (odds ratio estimate 4.81 with 95% confidence limits of 2.70-8.55). For agricultural occupations, the odds ratio was 1.62 with confidence limits of 1.05 to 2.49. The excess for previous primary cancer was largely due to previous skin cancer, especially in men, for whom the odds ratio was 13.7 (4.17-44.97). Multivariate analysis of these data, using the logit model, confirmed the association with both previous primary cancer and previous radiation. The rationale for a possible relationship between cutaneous neoplasms and salivary carcinoma is explained in embryologic and histogenetic terms.

Carcinoma↗
PubMed1996

Homozygous rapid arylamine N-acetyltransferase (NAT2) genotype as a susceptibility factor for lung cancer.

The polymorphic arylamine N-acetyltransferase (NAT2) is supposed to be a susceptibility factor for certain malignancies. A phenotyping study in 389 lung cancer patients revealed a similar distribution of rapid and slow acetylators by the caffeine test to that in 657 reference subjects (odds ratio, 1.05; 95% confidence limits, 0.81, 1.36; not significant). A separate group of 155 lung cancer patients was studied by genotyping NAT2 and was compared with a matched reference group of 310 unrelated patients and with 278 healthy volunteers. The NAT2 genotype was characterized by PCR-RFLP at nucleotide positions 191, 282, 341, 481, 590, 803, and 857. For evaluation of nucleotide 341, a 3'-mismatch primer was used. Homozygous wild-type genotypes NAT2*4/*4 were confirmed by DNA sequencing. Genotypes for rapid acetylation amounted to 43.9% among lung cancer and 41.6% among reference patients (odds ratio, 1.10 95% confidence limits, 0.73, 1.65; not significant). Discrimination into homozygous and heterozygous carriers of allele NAT2*4 revealed a distinct over-representation of NAT2*4/*4 genotypes amid lung cancer patients (odds ratio, 2.36; 95% confidence limits, 1.05, 5.32; P = 0.018). Logistic regression analysis considering sex, age, and smoking provided an odds ratio of 3.04 (95% confidence limits, 1.37, 6.75; P = 0.003). Hence, carriers of the NAT2*4/*4 genotype, with its especially high acetylation capacity, are at significantly increased risk to lung cancer.

Acetylation↗
PubMed2007

Risks of convulsion and aseptic meningitis following measles-mumps-rubella vaccination in the United Kingdom.

Measles-mumps-rubella (MMR) vaccines containing the Urabe strain of mumps were withdrawn in the United Kingdom in 1992 following demonstration of an increased risk of aseptic meningitis 15-35 days after vaccination. Following introduction of a replacement MMR vaccine (Priorix; GlaxoSmithKline, London, United Kingdom) in 1998, active surveillance of aseptic meningitis and convulsion was established to evaluate the risk associated with the new vaccine. No laboratory-confirmed cases of mumps meningitis were detected among children aged 12-23 months after administration of 1.6 million doses of Priorix (upper 95% confidence limit of risk: 1:437,000) in England and Wales. The upper 95% confidence limit excluded the risk found for mumps meningitis with Urabe vaccines (1:143,000 doses). No cases of aseptic meningitis were detected among children aged 12-23 months, who had received over 99,000 doses of Priorix (upper 95% confidence limit of risk: 1:27,000), in a regional database of hospital-admitted cases. This compares with an observed risk of 1:12,400 for Urabe vaccines. An elevated relative incidence of convulsion was found in the 6- to 11-day period after receipt of Priorix (relative incidence = 6.26, 95% confidence interval: 3.85, 10.18)-consistent with the known effects of the measles component of MMR vaccine-but not in the 15- to 35-day period (relative incidence = 1.48, 95% confidence interval: 0.88, 2.50) as occurred with Urabe-containing vaccines. This study demonstrates the power of active postmarketing surveillance to identify or exclude events too rare to be detected in prelicensure trials.

England↗
PubMed1989

The role of computed tomography in patients with lacunar stroke in the carotid territory.

In a prospective study of 78 patients presenting with recent clinical features of a supratentorially located lacunar infarct (LI), serial CT-scanning with contiguous 6, 5 or 3 mm slices was carried out. LI was found in 59 patients (76%; 95% confidence limits 65-85%). Lesions other than lacunar infarcts were found in 5 patients (6%; 95% confidence limits 2-14%); in only 14 patients could no abnormalities be detected (18%; 95% confidence limits 10-28%). There was no relationship between the detection rate on CT on the one hand and the type of lacunar syndrome, the number of previous TIA's, and the duration or severity of the neurological deficit on the other. A new protocol of CT-scanning for screening LI is advocated for situations where no MRI facilities are available or no patient cooperation can be obtained.

Adult↗
PubMed1986

Acupuncture in severe, stable angina pectoris: a randomized trial.

Twenty-six patients with stable angina pectoris, resistant to medical treatment, were randomized to either active or sham acupuncture in a single-blind design. Sham acupuncture was defined as the insertion of needles in a point within the same spinal segments as the active acupuncture, but outside the Chinese meridian system. The effect was evaluated from anginal attack rate, nitroglycerin consumption and exercise tests. Compared to patients receiving sham acupuncture the patients receiving active acupuncture increased cardiac work capacity significantly, expressed as dPRP (difference in pressure-rate-product between rest and maximum exercise) and maximal PRP during exercise (p less than 0.001). None of the other variables showed any significant difference between the two groups. Concerning exercise tolerance the median difference was 138 Wmin (95% confidence limits - 12.5 to 325 Wmin), concerning anginal attack rate the median difference was 29.5% (95% confidence limits 55% to -11%) and with regard to nitroglycerin consumption the median difference was 5% (95% confidence limits +67% to -44%). No significant effect of sham treatment was observed, no adverse effect was observed. We suggest that acupuncture may improve cardiac work capacity in patients with angina pectoris, refractory to medical treatment.

Acupuncture Therapy↗