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排序方式: 共有1511条查询结果,搜索用时 31 毫秒
991.
992.
Hydrogen breath testing versus LCT genotyping for the diagnosis of lactose intolerance: a matter of age? 总被引:1,自引:0,他引:1
Kerber M Oberkanins C Kriegshäuser G Kollerits B Dossenbach-Glaninger A Fuchs D Ledochowski M 《Clinica chimica acta; international journal of clinical chemistry》2007,383(1-2):91-96
BACKGROUND: Two single nucleotide polymorphisms (-13910 C/T and -22018 G/A) upstream of the lactase gene (LCT) have been found to be associated with lactose tolerance in Europeans. METHODS: In one hundred and twenty Austrian outpatients, who visited the physician's office for symptoms of irritable bowel syndrome (IBS), hydrogen breath testing (HBT) and LCT genotyping by polymerase chain reaction and reverse-hybridisation were performed in parallel. RESULTS: The coincidence between a genotype suggesting lactase non-persistence (lactose intolerance) and a positive HBT result was almost perfect (97.4% for LCT-13910 C/T and 100% for LCT-22018 G/A). Between a genotype indicating lactase persistence (lactose tolerance) and a negative HBT result the coincidence was lower (72% and 71.4%, respectively). Among heterozygotes, there was a statistically significant increase in the proportion of positive HBT results with age. Both SNPs were in accordance in 117/120 (97.5%) patients. CONCLUSION: Genetic analysis of LCT-13910 C/T and LCT-22018 G/A is a good indicator for the presence of lactose intolerance. Because age, as well as a number of secondary causes (e.g. celiac disease), can influence HBT results, it is useful to combine HBT and genetic analysis in the diagnostic assessment of IBS. 相似文献
993.
Modulation of macrophage iron transport by Nramp1 (Slc11a1) 总被引:2,自引:0,他引:2
Fritsche G Nairz M Theurl I Mair S Bellmann-Weiler R Barton HC Weiss G 《Immunobiology》2007,212(9-10):751-757
994.
Estrogen sulfotransferase expression in endometrial stromal sarcomas: an immunohistochemical study 总被引:1,自引:0,他引:1
Levels and activity of the enzyme estrogen sulfotransferase (EST) have been reported to play an important role in the regulation of in situ estrogen levels in human breast, prostate, and endometrial cancer. To better understand growth progression in endometrial stromal sarcomas (ESS), estrogen-dependent tumors, we analyzed the expression of EST in a series of 29 ESS. Archival formalin-fixed, paraffin-embedded material was analyzed immunohistochemically with a monoclonal antibody to EST using the peroxidase-antiperoxidase method. A score was calculated based on the percentage of positive tumor cells and staining intensity. EST staining was identified in 5 of 29 (18%) ESS and was scored as weakly positive, while 24 of 29 (82%) ESS were negative for EST. We demonstrate that a subset of ESS express EST, which may allow them to inactivate intratumoral estrogens. ESS without EST expression may have increased levels of biologically active estrogen, which explains the tumor progression of this entity and these patients may be at increased risk for recurrences and metastases. 相似文献
995.
Schmid G Uberbacher R Samaras T Tschabitscher M Mazal PR 《Physics in medicine and biology》2007,52(17):5457-5468
In order to enable a detailed analysis of radio frequency (RF) absorption in the human pineal gland, the dielectric properties of a sample of 20 freshly removed pineal glands were measured less than 20 h after death. Furthermore, a corresponding high resolution numerical model of the brain region surrounding the pineal gland was developed, based on a real human tissue sample. After inserting this model into a commercially available numerical head model, FDTD-based computations for exposure scenarios with generic models of handheld devices operated close to the head in the frequency range 400-1850 MHz were carried out. For typical output power values of real handheld mobile communication devices, the obtained results showed only very small amounts of absorbed RF power in the pineal gland when compared to SAR limits according to international safety standards. The highest absorption was found for the 400 MHz irradiation. In this case the RF power absorbed inside the pineal gland (organ mass 96 mg) was as low as 11 microW, when considering a device of 500 mW output power operated close to the ear. For typical mobile phone frequencies (900 MHz and 1850 MHz) and output power values (250 mW and 125 mW) the corresponding values of absorbed RF power in the pineal gland were found to be lower by a factor of 4.2 and 36, respectively. These results indicate that temperature-related biologically relevant effects on the pineal gland induced by the RF emissions of typical handheld mobile communication devices are unlikely. 相似文献
996.
997.
998.
Age-related rhabdosphincter function in female urinary stress incontinence: assessment of intraurethral sonography. 总被引:5,自引:0,他引:5
Andrea Klauser Ferdinand Frauscher Hannes Strasser Gernot Helweg Dieter Klle Dagmar Strohmeyer Arnulf Stenzl Dieter zur Nedden 《Journal of ultrasound in medicine》2004,23(5):631-7; quiz 638-9
OBJECTIVE: To assess dynamic intraurethral sonography in the diagnostic evaluation of the function of the rhabdosphincter in female patients with urinary stress incontinence in relation to patient age. METHODS: Sixty-two patients with clinically proved urinary stress incontinence were investigated by means of intraurethral sonography with a 12.5-MHz endoluminal 9F catheter. The omega-shaped rhabdosphincter was visualized at rest and during voluntary contractions. Changes of muscle thickness and transducer-sphincter distance were measured and considered as parameters of muscle function. The intraurethral sonographic data were compared with results of standard urodynamic tests. RESULTS: Transducer-sphincter distance and sphincter muscle thickness showed a significant decrease with positive linear dependency on patient age (P < .001). Patients with grade III urinary stress incontinence had complete loss of sphincter contractility. A negative correlation was revealed between urethral closure pressure and patient age. CONCLUSIONS: We found an age-related decrease in rhabdosphincter function. Our results suggest that the rhabdosphincter is a substantial component of the continence mechanism in female urinary stress incontinence. Unlike urethral pressure profiles, which can only reveal zones of higher intraluminal pressure, transurethral sonography is highly specific for measurement of the function of the rhabdosphincter. 相似文献
999.
Grechenig W Mayr JM Peicha G Hammerl R Schatz B Grechenig S 《Journal of clinical ultrasound : JCU》2004,32(7):338-343
PURPOSE: The aim of this study was to describe typical age-related sonographic features of the Achilles tendon and calcaneal apophysis in children, providing a reference for the assessment of heel pathologies during the growth period. METHODS: The calcaneal apophysis and Achilles tendon insertion of 100 children 2 months to 18 years old were examined by high-frequency gray-scale and color Doppler sonography along both the longitudinal and transverse planes. The thicknesses of the apophyseal cartilage at the calcaneal tuberosity and of the Achilles tendon were measured. Also, the sonographic appearance of the bone-cartilage interface was studied. RESULTS: In children 2 months to 3 years old, the cartilage of the calcaneal tuberosity apophysis was anechoic, with small scattered echoes. In 19 of these 25 children (76%), the echogenic areas contained at least 1 small vessel, visualized on color Doppler sonography. In 15 of 25 children (60%) 4-6 years old, a wavy interface was noted at the junction of the calcaneus and the apophyseal cartilage. CONCLUSIONS: High-frequency sonography can yield reliable information about the bone-cartilage interface and the Achilles tendon insertion site at the calcaneal tuberosity in children. The sonographic features of the normal heel described here may contribute to improved assessment of pathologies in this anatomic region. 相似文献
1000.
Walder G Falkensammer B Aigner J Tiwald G Dierich MP Würzner R Lechleitner P 《Wiener klinische Wochenschrift》2003,115(7-8):263-266
We report the first documented case of human granulocytic ehrlichiosis (HGE) in Austria. The infection was acquired near Arzl in the surroundings of Innsbruck in northern Tyrol. Except for a biphasic course of illness, presentation in this 33-year-old female patient was comparable to clinical findings observed in other European adults with high fever, transient thrombocytopenia, elevated levels of CRP and LDH, arthralgias, myalgias, fatigue and subfebrile temperature. Flu-like symptoms started about seven days after a tick bite and lasted for ten days, followed by an asymptomatic interval of three days and an acute onset of fever up to 39.5 degrees C on day 20. On admission, the patient showed high antibody titres against Anaplasma phagocytophilum (IgG 1:1024, IgM 1:640); six weeks later the IgG-titre had risen to 1:2048, and IgM-levels had fallen below 1:40. The demonstration of anti-platelet antibodies in acute-phase serum was noteworthy. We conclude that also in Austria HGE should be considered in patients with febrile thrombocytopenia, especially when the medical history reveals recent tick exposure. 相似文献