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61.
Eric Schulze‐Bahr Lars Eckardt Günter Breithardt Karlheinz Seidl Thomas Wichter Christian Wolpert Martin Borggrefe Wilhelm Haverkamp 《Human mutation》2005,26(1):61-61
In supplementation of previously published cardiac sodium channel (SCN5A) gene mutations that were cited in the text, in Table 2 and in Figure 2 we here apply an updated gene mutation nomenclature (Human Genome Variation Society, 2005) to facilitate mutation annotation comparison (SCN5A cDNA reference: NM_198056.1 or GI: 37622906; amino acid reference sequence: SWISS‐PROT entry Q14524, long splice variant, 2,016 amino acids): Mutation: c.2602delC Amino acid change: p.Glu868X Mutation: c.2581_2582delTT Amino acid change: p.Phe861Trp fsX90 Mutation: c.4477_4479delAAG Amino acid change: p.Lys1493del Mutation: c.5425C>A Amino acid change: p.Ser1812X 相似文献
62.
Jacques Chappuis Igor A. Sherman A. Wilhelm Neumann 《Annals of biomedical engineering》1983,11(5):435-449
Measurements of the surface tension of articular cartilage and friction experiments were carried out to provide further evidence
in support of a new theory regarding the mechanism of friction in joints. To determine the surface tension of cartilage, contact
angle measurements were used in conjunction with the equation of state for interfacial tensions. The advancing contact angle
between saline drops and articular cartilage was found to be 100°±5°, indicating a highly hydrophobic surface. The corresponding
surface tension value was calculated to be 22.5 ergs/cm2. Friction of cartilage against hydrophobic surfaces is shown to be lower than the friction of cartilage against hydrophilic
surfaces. All these results further support the theory that lubrication by nonwetting drops occurs in joints and may be responsible
for the exceptional friction characteristics of the joints. 相似文献
63.
1. The temperature of the spinal cord (Tvc) was measured in unanaesthetized pigeons at different ambient temperatures (Ta). 2. In short-term experiments spontaneous or noncyclic variations of Tvc at constant (20 and 10 degrees C) and changing Ta were correlated with the amplitude of the electromyogram EMG) which indicates shivering, i.e., heat production. At constant Ta no unequivocal correlation between Tvc (and also Tskin) and EMG was found. During ambient cooling there was often an increase of Tvc which resulted in a positive correlation whereas there was a negative correlation to Tskin. 3. In long-term experiments (24h, LD 12:12Y cyclic variations of Tvc were measured at different Ta and ocrrelated with O2-consumption, i.e., heat production. As with body temperature Tvc was lowered during the dark phase of the diurnal cycle. In the light phase both Tvc and heat production increased with decreasing Ta which results in a positive correlation. In the dark phase there was a smaller increase in heat production but a decrease in Tvc, i.e., a negative correlation. 4. The results show that natural variations of Tvc are often positively ocrrelated with heat production. This is in contrast to experimental changes of Tvc where a clear negative correlation to heat production can be observed. 相似文献
64.
Alteration of the LRP1B gene region is associated with high grade of urothelial cancer 总被引:6,自引:0,他引:6
Langbein S Szakacs O Wilhelm M Sukosd F Weber S Jauch A Lopez Beltran A Alken P Kälble T Kovacs G 《Laboratory investigation; a journal of technical methods and pathology》2002,82(5):639-643
We have delineated regions of interest at chromosome 2q21.2, 2q36.3, and 2q37.1 by deletion mapping of 114 urothelial cancers (UC). Altogether, 17%, 18%, and 63% of the G1, G2, and G3 tumors displayed loss of heterozygosity at chromosome 2q, respectively, The region at 2q21.2 was narrowed down to the LRP1B gene (NT_005129.6). Hemi- and homozygous deletion at the LRP1B gene region was seen in 31 of 114 UCs. Only 8% of the UCs with G1 and none with G2 tumors showed loss of heterozygosity at the LRP1B gene, whereas 49% of the G3 UCs had allelic loss at this region. RT-PCR analysis of the LRP1B gene showed the lack of expression of several exons in 2 of 9 cases analyzed. Our analysis suggests that the LRP1B gene is a candidate tumor suppressor gene in UCs. 相似文献
65.
66.
Identification of a novel coronavirus in patients with severe acute respiratory syndrome 总被引:1,自引:0,他引:1
Drosten C Günther S Preiser W van der Werf S Brodt HR Becker S Rabenau H Panning M Kolesnikova L Fouchier RA Berger A Burguière AM Cinatl J Eickmann M Escriou N Grywna K Kramme S Manuguerra JC Müller S Rickerts V Stürmer M Vieth S Klenk HD Osterhaus AD Schmitz H Doerr HW 《The New England journal of medicine》2003,348(20):1967-1976
67.
R. Fuchs T. Thalhammer M. Peterlik J. Graf 《Pflügers Archiv : European journal of physiology》1986,406(4):430-432
Mechanisms of Na+–H+ exchange in the hepatocyte were studied utilizing isolated basolateral membrane vesicles prepared by two different methods: Evidence was obtained for the existence of molecular coupling of Na+ and H+ fluxes (Na+/H+-antiport) which exhibits saturation kinetics (Km 7 mmol/l Na+) and is inhibited by amiloride (1.0 mmol/l). Although the two membrane preparations showed differences with respect to ionic permeabilities, our data suggest that a relatively high H+ conductance exists in the basolateral plasma membrane. Hence, electrical coupling of conductive H+ and Na+ fluxes in the opposite direction could contribute to net Na+–H+ exchange across the basolateral hepatocyte plasma membrane. 相似文献
68.
Conservative treatment of cervical pregnancy by curettage and local prostaglandin injection 总被引:2,自引:4,他引:2
Spitzer D; Steiner H; Graf A; Zajc M; Staudach A 《Human reproduction (Oxford, England)》1997,12(4):860-866
Recently, various conservative regimens for the treatment of cervical
pregnancy have been introduced to preserve fertility in young women, with
methotrexate being one of the most widely used drugs. The success of
conservative treatment depends on early preoperative diagnosis. We report
three cases of first trimester cervical pregnancy, successfully treated by
curettage to evacuate the conceptus, followed by local prostaglandin
instillation to prevent severe haemorrhage. In one patient, intra-amniotic
instillation of hyperosmolar glucose was necessary to terminate fetal
cardiac activity. beta-Human chorionic gonadotrophin returned to normal
within 3 weeks in one patient and within 7 weeks in another, both of whom
became pregnant again within 1 year, resulting in term deliveries. The
third patient was lost to follow-up after 1 week. The advantage of
prostaglandin and curettage is the absence of major side-effects to the
mother or the fetus of a subsequent pregnancy. The management strategies
used in the treatment of cervical pregnancies and the results obtained
since the introduction of methotrexate in 1989 are discussed in the context
of previously published literature. The incidence of subsequent pregnancies
among women treated medically versus women treated surgically is reported.
相似文献
69.
A case of papillary-cystic variant of acinic-cell adenocarcinoma is described. The cytologic findings differed significantly from the classic features of this tumor with smears showing large monolayer sheets and small papillary groups, no acinic structures or naked tumor cell nuclei, sparse cell dissociation and many vacuolated cells. © 1994 Wiley-Liss, Inc. 相似文献
70.
Cavitation potential of mechanical heart valve prostheses 总被引:3,自引:0,他引:3
Just like technical check valves, the function of mechanical heart valve prostheses may presumably also lead to cavitation effects during valve closure. Due to the waterhammer effect, cavitation may primarily occur in the mitral position leading to high mechanical loading of the valve itself and of corpuscular blood elements. Ten different types of commercial mechanical heart valves were investigated in the mitral position of a pulsatile mock loop, to detect cavitation thresholds under physiologically similar conditions by cinematographic techniques. Almost all these valve prostheses show cavitation up to a ventricular pressure gradient of 5000 mmHg/s. The threshold depends on valve type and size and is sometimes within the physiological range below 2000 mmHg/s. Visible cavitation bubbles with a diameter of up to 1.8 mm and a collapse time of less than 0.1 ms suggest that vapour cavitation may play an important role for material and blood damage in mechanical heart valve prostheses. 相似文献