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991.
The aim of the study was to evaluate the odontometric characteristics of female-to-male transsexuals (FtM) in comparison to control groups of males and females. A total of 48 FtM, aged 20–28 years, were studied. For each tooth, two standard measurements were taken: the mesiodistal (MD) and the buccolingual (BL) diameter of the crown. Significant differences between males and females were found in BL measures of all maxillary teeth as well as mandibular lateral incisor and canine. Within the MD measures, the most distinguishing were maxillary and mandibular canines and the first molars. For seven teeth, there were a total of 14 comparisons of MD (half for the maxilla and half for the mandible) between the control men and women. Of these, the men had larger diameters for 12, of which four were statistically significant. There were also a total of 14 comparisons of BL diameter; of these, the men had larger diameters for 13, of which nine were statistically significant. For seven teeth, there were a total of 14 comparisons of MD between the control men and the FtM. Of these, the men had larger diameters for 12, of which seven were statistically significant. There were also 14 comparisons of BL; of these, the men had larger diameters for 10, of which six were statistically significant. For seven teeth, there were a total of 14 comparisons of MD between the control women and the FtM. Of these, the women had larger diameters for nine, of which three were statistically significant. There were also a total of 14 comparisons of BL; of these, the FtM had larger diameters for 13, of which five were statistically significant. Our study revealed that the shift of values of metric features in teeth of FtM towards males was more frequent in the more sexually dimorphic BL diameters characterized by significantly greater width of the crown of five teeth: maxillary canine, first and second molars, as well as mandibular incisors. The results showed intermediate status of female-to-male transsexuals’ teeth between the males and females, which may suggest a genetic basis of transsexualism.  相似文献   
992.
993.
Gastrointestinal (GI) nematode infections affect 50% of the human population worldwide, and cause great morbidity as well as hundreds of thousands of deaths. Despite modern medical practices, the proportion of the population infected with GI nematodes is not falling. This is due to a number of factors, the most important being the lack of good healthcare, sanitation and health education in many developing countries. A relatively new problem is the development of resistance to the small number of drugs available to treat GI nematode infections. Here we review the most important parasitic GI nematodes and the methods available to control them. In addition, we discuss the current status of new anthelmintic treatments, particularly the plant cysteine proteinases from various sources of latex-bearing plants and fruits.  相似文献   
994.
This review discusses the present knowledge on the oxygen uptake kinetics at the onset of exercise in skeletal muscle and the contribution of a previously developed computer model of oxidative phosphorylation in intact skeletal muscle to the understanding of the factors determining this kinetics on the biochemical level. It has been demonstrated recently that an increase in the total creatine pool [PCr + Cr] and in glycolytic ATP supply lengthen the half-transition time of the VO2 on-kinetics, while an increase in mitochondria content, in parallel activation of ATP supply and ATP usage, in muscle oxygen concentration, in proton leak, in resting energy demand, in resting cytosolic pH, and in initial alkalization diminish this parameter. It has also been shown that the half-transition time is near-linearly proportional to the absolute difference between the phosphocreatine concentration during work and at rest (deltaPCr). The present review discusses whether the V/O2 on-kinetics on the muscle level is strictly or only approximately exponential. Finally, it is postulated that a short transition time of the VO2 on-kinetics in itself does not need be profitable for the skeletal muscle functioning during exercise, but usually a short transition time is correlated with factors that improve exercise capacity. The transition time is a phenomenological parameter resulting from the biochemical properties of the system and not a physical factor that can cause anything in the system.  相似文献   
995.
A series of thiourea derivatives of 4-azatricyclo[5.2.2.02,6]undec-8-ene-3,5-dione were synthesized. The compounds were investigated for antibacterial activity, including Gram-positive cocci, Gram-negative rods, and antifungal activity. Compounds 1b, 2b, 4b showed significant inhibition against Gram-positive cocci. Research was carried out over 10 standard strains and 20 hospital strains. Synthesized compounds were evaluated for their cytotoxicity and anti-HIV-1 activity in MT-4 cells.  相似文献   
996.
Cancer cachexia (CC), a progressive loss of body mass, is associated with decreased energy production. Abnormally low levels of L-carnitine (LC) in skeletal muscle means that mitochondrial β-oxidation of long-chain fatty acids (LCFA) does not occur efficiently in patients with CC. We assessed the influence of CC on LC distribution and the effects of parenteral lipid emulsions on plasma LC levels and urinary excretion. Fifty patients with CC were randomly assigned to total parenteral nutrition (TPN) with long-chain triglycerides (LCTs), or LCTs plus medium-chain triglycerides (MCTs) as 50/50. Patients were further separated into those with body-mass index (BMI) ≤ 19 kg/m(2) and BMI >19 kg/m(2). Plasma concentrations of total LC (TC) and free LC (FC) and their urinary excretion were measured, along with skeletal muscle LC levels. On average, plasma FC and TC were higher than reference values in all patients. Patients with BMI ≤ 19 kg/m(2) had lower plasma FC and TC than those with BMI >19 kg/m(2). Skeletal muscle FC in the BMI ≤ 19 kg/m(2) group was lower than reference value, but within the normal range in others. LC and FC urinary excretion was higher than reference values. Plasma LC and its urinary excretion were higher in patients administered pure LCTs relative to those given MCTs/LCTs. A decrease in skeletal muscle LC in cancer patients with CC (BMI ≤ 19 kg/m(2)) correlates with an increase in its plasma levels and increased renal excretion. A diet of MCTs/LCTs reduces LC release from muscle to plasma and urine more effectively than LCTs.  相似文献   
997.
Solid phase extraction (SPE) was introduced as a crucial step in the HPLC-SPE-NMR technique to enable online analyte enrichment from which proton-detected NMR experiments on submicrogram amounts from complex mixtures were possible. However, the significance of direct-detected (13)C NMR experiments is indubitable in simplifying structural elucidations. In the current study, we demonstrated direct (13)C NMR detection of triterpenoids from a Ganoderma lucidum extract in hyphenation mode. The combined advantage of a cryogenically cooled probe, miniaturization, and multiple trapping enabled the first reported application of HPLC-SPE-NMR analysis using direct-detected (13)C NMR spectra. HPLC column loading, accumulative SPE trappings, and the effect of different elution solvents were evaluated and optimized. A column loading of approximately 600 μg of a prefractionated triterpenoid mixture, six trappings, and an acquisition time of 13 h resulted in spectra with adequate signal-to-noise ratios to detect all C-13 signals.  相似文献   
998.
We have recently reported that fibrillar amyloid beta-protein (Abeta) inhibits the proteolytic activity of trypsin and high molecular weight bovine brain protease. We report here that trypsin binds to fibrillar Abeta (fAbeta) and the resulting complex of trypsin/fAbeta is sodium dodecyl sulfate (SDS)-stable. Electron microscopic analysis confirmed the binding of trypsin on the fibrils of both Abeta 1-40 and Abeta 1-42. SDS-polyacrylamide gel electrophoresis (PAGE) of fAbeta sample incubated in the presence of trypsin showed that major amount of trypsin was associated with fAbeta that did not enter the gel. The presence of trypsin in this protein complex was confirmed by Western blotting after its elution from the gel. Kinetic studies showed that the binding of trypsin to fibrillar Abeta was dependent on the degree of Abeta fibrillization and on the concentration of fAbeta. However, the trypsin binding to Abeta oligomers did not affect the fibril growth. The maximum binding (B(max)) of trypsin to fAbeta 1-40 and fAbeta 1-42 was 36 pmol and 40 pmol, and dissociation constant (K(d)) was 18.31 microM and 20 microM respectively. Similar to fAbeta, trypsin could also bind to fibrillar amylin. This binding was dependent on the concentration of fibrillar amylin. Under similar conditions, bovine serum albumin did not bind to fibrillar Abeta. These results suggest that fAbeta and fibrillar amylin have strong affinities for trypsin, and chelation of proteases by abnormal aggregated proteins may be a general mechanism for inflicting pathological conditions in various diseases.  相似文献   
999.
BACKGROUND AND PURPOSE: The aim of the study was to estimate the usefulness of the antineoplastic vaccination in treatment of malignant brain tumors. According to medical knowledge there is no cure for this kind of tumors. MATERIAL AND METHODS: Between 2001 and 2005, ten patients suffering from malignant glial tumors were treated. There were 5 male and 5 female individuals, aged from 17 to 76 (mean age: 40.8 years). The histopathological examination showed 4 cases of glioblastoma and 6 cases of anaplastic astrocytoma. Initially, patients were operated on with dissection of 1 cm(3) of the most representative part of tumor. The neoplasm cells were cultured, transfected with episomal pMT EP vector (expressing alternatively oligonucleotide sequence forming triple helix with IGF-I gene or antisense against IGF-1 mRNA), re-cultured, irradiated and resuspended in medium to prepare antineoplastic vaccine. The patients were vaccinated subcutaneously. We examined peripheral blood lymphocyte subsets to assess the immunological response of the patients. RESULTS: We observed prolongation of the survival time to 21.7 months compared to 9-11 months observed in literature. The patients were additionally treated oncologically with radiotherapy and chemotherapy (temozolomide) according to the reasonable indications. Therefore, the comprehensive assessment of the genotherapy as the supplemental monotherapy was impossible. CONCLUSIONS: The method of treatment used in this study prolongs the survival time of patients with high-grade gliomas of the central nervous system. This gene therapy needs further investigations as a method of oncological monotherapy of brain malignant gliomas.  相似文献   
1000.
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