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Ohne Zusammenfassung
Validation of diagnostic tests
  相似文献   
996.
Based on current evidence from the literature, the prognosis, treatment and outcome of lupus erythematosus are presented with special reference to difficulties encountered in the management of patients with involvement of the oral cavity. Original iconography of illustrative treated cases is included.  相似文献   
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High bone resorption by the osteoclast results in osteoporosis, a disease affecting 40% of women after the menopause. Calcitonin, used to treat osteoporosis, inhibits bone resorption via receptors located on the osteoclasts. Two alleles of the calcitonin receptor gene ( CTR ) exist: a base mutation T-->C in the third intracellular C-terminal domain changes a proline (CCG) at position 447 to a leucine (CTG). We therefore studied the distribution of these alleles in a cohort of 215 post-menopausal Caucasian women suffering or not from osteoporotic fractures. The region of interest within the point mutation was amplified by PCR and screened for single strand conformation polymorphism. This work was followed by DNA sequencing of the fragments amplified. We found that bone mineral density (BMD) at the femoral neck was significantly higher in heterozygous subjects with the Rr genotype compared with the homozygous leucine (RR) and homozygous proline (rr) genotypes. Also, a decreased fracture risk was observed in heterozygote subjects. In conclusion, our results suggest that polymorphism of CTR could be associated with osteoporotic fractures and BMD in a population of post-menopausal women. CTR heterozygotes could produce both alleles of the receptor. The heterozygous advantage effect of Rr subjects could explain their protection against osteoporosis: higher bone density and decreased fracture risk. Establishing the genotype of the CTR gene in post-menopausal women could be of value in evaluating their risk of developing fractures.   相似文献   
999.
Female cigarette smoking has been implicated as having a detrimental effect on in-vitro fertilization (IVF) outcomes mediated through: (i) a diminished ovarian reserve (DOR), and (ii) an elevated pregnancy loss. Research is sparse regarding the effect of male smoking. The objective of this retrospective cohort study was to investigate the effect of male and female smoking on: (i) the collective quality of embryos selected for uterine transfer, and (ii) the likelihood of achieving an ongoing pregnancy at 12 weeks. A total of 498 consecutive IVF treatment cycles were analysed. Female smokers were significantly younger (P < 0.05) and achieved a better modified cumulative embryo score (mCES) (P < 0.05) than female non-smokers. Female age correlated inversely with the number of oocytes collected (r = -0.42, P < 0.01) and the number of oocytes in turn was important in terms of predicting mCES. The decreasing number of oocytes aspirated with increasing age was of a significantly stronger magnitude for female smokers than for female non- smokers (P < 0.05). Multiple logistic regression was used to determine whether smoking affected the likelihood of achieving a 12-week pregnancy. The mCES, tubal infertility and male smoking were found to be significant. Male smoking interacted with male age (P = 0.0164), indicating for male smokers a decrease of 2.4% in the likelihood of achieving a 12-week pregnancy with every 1-year increase in age. This is the first study to show that male smoking has a deleterious effect on pregnancy outcome among IVF patients. Our study supports the increased risk of DOR but fails to support the elevated incidence of pregnancy loss among female smokers. A reduced pregnancy rate was associated with male smoking possibly through pre-zygotic genetic damage. The growing realization of a paternal component of reproductive impairment suggests that studying the male is necessary.   相似文献   
1000.
Summary— The alkaloid cycleanine ([12aR-(12aR,24aR)]-2,3,12a,13,14,15,24,24a-octahydro-5,6,17,18-tetramethoxy-1,13-dimethyl-8,11: 20,23-dietheno-1H,12H [1,10]dioxacyclooctadecino[2,3,4-ij: 11,12,13-i'j']diisoquinoline) was extracted from the bulbs of Stephania glabra (Roxb) Miers and its effects on cardiac and smooth muscle preparations were studied and compared to those of nifedipine (1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl)-3,5-pyridine dicarboxylic acid dimethylesther). Cycleanine inhibited the KCl-induced contraction of rabbit aortic rings with higher potency than nifedipine. IC50s for cycleanine and nifedipine were 0.8 and 7·10−9 M respectively. Cycleanine had minor effects on the norepinephrine-induced contraction of rabbit aortic rings. Cycleanine and nifedipine also depressed the contraction of rat ventricular preparations but with lower potency (IC50 = 3 and 0.03·10−6 M respectively). Action potential duration of rat right ventricular strips was decreased by both compounds. L-type Ca-current (ICaL) of single rat ventricular cardiomyocytes was inhibited by cycleanine in a voltage- and frequency-dependent manner. With a higher potency nifedipine inhibited ICaL in a tonic and almost frequency-independent manner. The results suggest that cycleanine can act as a potent vascular selective Ca-antagonist.  相似文献   
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