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Biomedical subjects

H Klaus

Publications and source records attributed to H Klaus.

At least 19 recordsLinked to original sources
PubMed1998

Influence of the hepatobiliary contrast agent mangafodipir trisodium (MN-DPDP) on the imaging properties of abdominal organs.

To assess the influence of Mangafodipir Trisodium on the imaging properties of abdominal organs when using T1-weighted gradient-echo (GE) and T2-weighted turbo spin-echo (TSE) sequences, thirty patients with focal lesions in the liver were examined at a field strength of 1.5 T before and after intravenous administration of Mangafodipir Trisodium (dose: 5 micromol/kg of body weight). Administration of Mangafodipir Trisodium led to a significant increase in the signal intensity of the liver tissue (p < 0.001), the spleen (p < 0.01), the pancreas (p < 0.001), and the kidneys (p < 0.001) in the T1-weighted GE sequence, while there was no relevant enhancement in fatty tissue and the musculature. In the T2-weighted turbo spin-echo sequence, there was no relevant change in the signal following administration of a contrast agent. The contrast-to-noise ratio (C/N) between the lesions and the liver tissue increased significantly in the post-contrast T1-weighted GE sequence (p < 0.001), while there was no change in the contrast-to-noise ratio in the post-contrast T2-weighted turbo spin-echo sequence. The contrast-to-noise ratio of the plain T2-weighted TSE sequence was significantly higher than that in the post-contrast T1-weighted GE sequence (p < 0.001). Although Mangafodipir Trisodium was primarily developed as a hepatobiliary contrast agent for demonstration and differentiation of liver lesions, it also affects the signal levels in the pancreas, spleen, and kidneys in the T1-weighted image. Awareness of this effect on the extrahepatic tissue makes it easier to interpret pathological findings in magnetic resonance imaging (MRI) of the abdomen.

Abdomen↗
PubMed1991

Histopathology studies in human malignant melanomas of the choroid after unsuccessful treatment with 106Ru/106Rh ophthalmic applicators.

Choroidal malignant melanomas were examined after unsuccessful brachytherapy with 106Ru/106Rh ophthalmic plaques. The histologic findings were compared with those obtained in non-irradiated melanomas similar in size and location. Both groups revealed no significant clinical difference apart from the lower average age of the irradiated patients. Some of the histologic features (scar formation, changes in the distribution of cell types, rate of mitosis) represented reactions to irradiation. No single histologic feature was strongly correlated to the irradiated group. The phenomenon of radioinsensitivity observed in some malignant melanomas cannot be fully elucidated using conventional histologic methods.

Brachytherapy↗
PubMed1991

Ovulation method use during breastfeeding: is there increased risk of unplanned pregnancy?

Data from two prospective studies of the ovulation method were used to assess pregnancy rates and users' fertility-related behaviors among breastfeeding women. The rate of unplanned pregnancy was less than 1% during the first 6 months of lactational amenorrhea. However, the unplanned pregnancy rate was elevated among breastfeeders during the months after menses return compared with the pregnancy rate during nonlactating cycles. Rates were also elevated at the time when infant feeding supplementation was started. This increase in unplanned pregnancies was not directly attributable to nonadherence to the ovulation method rules; there was some indication that adherence to the rules actually may be increased during those months. Therefore, special emphasis on both the need for improved breastfeeding support to delay menses return and the increased potential for method failure among new users during this period of time should be incorporated into ovulation method training and support programs.

Breast Feeding↗
PubMed1991

Efficacy studies in natural family planning: issues and management implications illustrated with data from five studies.

Studies of method effectiveness must be carefully assessed for comparability of findings. Several parameters are identified that are important in the assurance of comparable results. This article discusses these issues with the use of data from previously published studies and emphasizes the management implications of use-effectiveness data.

Data Interpretation, Statistical↗
PubMed1989

Excision repair differences in rat fibroblasts.

By using a cellular transformation system, which has been developed by Graffi et al., we analysed differences in the excision capacity of UV-induced dimers in normal cells, in vitro transformed cells and in malignant cells derived from a rat fibrosarcoma. The results suggest that both the transformed and the tumour-derived cells exhibit a kinetic pattern of excision repair different from that of the normal cells. Recognition of the dimers and the incision rate are more complete in the normal cell.

Animals↗
PubMed1989

Recognition of ovulatory/anovulatory cycle pattern in adolescents by mucus self-detection.

The high frequency of anovulation during adolescence raises the question of whether a method for the recognition of ovulation by self-detection of cervical mucus patterns is useful in teenagers. We performed a secondary analysis of 1049 completely recorded cycles of 235 teen women 15-17 years of age with a gynecologic age from less than 1 to 7 years. These subjects had learned to monitor their fertility patterns using the Billings Ovulation Method. The cycles were analyzed by the length of the mucus and luteal phases and recorded "peak symptom." Ovulatory cycles were grouped by the length of the luteal phase, short (4-8 days) and average (8-18 days), and plotted against gynecologic age. The frequency of anovulatory cycles was comparable to Vollman's age-stratified monophasic cycle groups. Ovulatory patterns were found at gynecologic ages of 1 year, 49%; 2 years, 60%; 3 years, 72%; 4 years, 61%; 5 years, 86%; and 6 years, 71%. The study proved that teen-age women can distinguish patterns of ovulation and anovulation by self-detection of cervical mucus.

Adolescent↗
PubMed1988

Factors related to ovulation method efficacy in three programs: Bangladesh, Kenya, and Korea.

Sociodemographic and reproductive health data were gathered on approximately 200 acceptors in each of three programs offering the Ovulation Method of Natural Family Planning. The programs were located in Bangladesh, Kenya, and Korea. In addition, a one year follow-up was attempted to assess continuation and efficacy. Descriptive data show a variety of religious, educational, income, family, and family planning backgrounds among acceptors. Life table analyses of reported unplanned pregnancy occurrence among spacers and limiters combined was 15% at 12 months in Bangladesh, 11% in Kenya and 13% in Korea. The pregnancy rate at 12 months for all pregnancies, planned and unplanned, was 27.0, 26.0, and 23.7, respectively. In Bangladesh 37 of the 48 unplanned pregnancies were user-related as were all of the 14 unplanned pregnancies in Kenya and 17 of the 20 in Korea. Method failure was the reported cause of pregnancy in only 2 of the 83 unplanned pregnancies. A major aspect of this study was the assessment of higher risk population subgroups; increasing age, education, previous pill use and previous family planning are significantly associated with fewer unplanned pregnancies while religion, attendance as a couple, family planning intention, size and source of referral do not have a demonstrated impact on pregnancy occurrence. The time of entry into the data set in relation to time of initial NFP acceptance may be an important variable in assessing OM effectiveness.

Adolescent↗
PubMed1988

Detection of soluble fibrin monomer complexes. Comparison of a haemagglutination assay with the ethanol gelation test.

Hypercoagulability and disseminated intravascular coagulation (DIC) are characterized by the presence of circulating fibrin monomer complexes in plasma. In 342 patients with possible DIC fibrin monomers, fibrinogen, Reptilase Time, antithrombin III and other coagulation parameters were determined at frequent intervals. Testing of soluble fibrin monomer complexes was performed using a sensitive and reliable hemagglutation assay with red cells sensitized by fibrin monomers (FM-Test) and the ethanol gelation test (EGT). Method comparison regarding the influence of fibrinogen levels and fibrin degradation products shows that high fibrinogen levels lead to false-positive results with EGT. The same effect is observed for fibrin degradation products and EGT whereas no influence of fibrinogen level and fibrin degradation products on the FM-Test occurs. It is well-known that during DIC AT III level decreases caused by proteolytic activity. In this study it could be shown that fibrin monomer increases parallel to the decrease of AT III. The same effect does not occur due to fibrin degradation products.

Blood Coagulation Tests↗
PubMed1985

Automated microscope image analysis in the cytological tumor diagnostics. Results on borderline-cases of mammary tumors.

50 fine-needle biopsies of mammary tumors (20 medullary carcinomas, 20 fibroadenomas, and 10 false negative judged cases) were studied by automated microscopic image analysis. Eight morphometric and densitometric features of the tumor cell nuclei were determined on Papanicolaou stained smears. It was analyzed whether smears false judged as negative can be rightly allocated as carcinomas by the automated method. The results of this study have shown that it was possible by means of three cell nucleus parameters (standard deviation of the area, mean area ratio, and skewness of the grey value gradient at contours) with 100% correct separation of the unequivocal cytologies into malignant and benign smears to recognize about 90% of the false judged smears rightly as carcinomas. The results are reproducible and can be obtained in a time of 2-5 min per smear. The first results show that the automated microscope image analysis may be a valuable tool in the diagnosis of borderline-cases of mammary tumors.

Adenofibroma↗
PubMed1984

Effect of diets containing varying concentrations of essential fatty acids and triglycerides on renal function in uremic rats and NZB/NZW F1 mice.

Influences of essential fatty acids (EFA) and triglycerides as reasons for the progression of chronic renal failure are still in debate. We studied the outcome of four diets containing different concentrations of triglycerides and EFA in 5/6 nephrectomized rats and in NZB/W mice up to 45 weeks. The results showed no significant differences in the outcome of survival rate, proteinuria, urea, and creatinine levels as well as histological findings in the different groups of both animal models. We conclude that diets containing EFA up to C18:2 or being free of EFA or that triglyceride-enriched diets have no influence on the natural course of the renal disease in these both experimental models.

Animals↗