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11.
S Schmidt S Gorissen H Eilers H Fahnenstich A Dorer D Krebs 《Journal of perinatal medicine》1991,19(1-2):107-113
Laserspectroscopy with near-infrared light is newly available for clinical application. The equipment consists of a near-infrared data collection unit (NIRDCU) and a personal computer. Emission of laser light at wavelengths of 775, 805, 845 and 904 nm is provided by the four laser diodes of the NIRDCU. By analyzing changes of optical density during laser radiation, information is obtained regarding the intracellular redox state and relative changes of blood volume. During measurement with the system on the fetal scalp during delivery we were able to get a first impression of the method's potential. While the application of the laser sensors is still cumbersome, signals providing information of the relative changes of hemoglobin concentration, relative changes of blood volume and cytochrome aa3 seems achievable. Laserspectrophotometric monitors may become safe, low cost and portable instruments for the non-invasive assessment of the biochemical and biophysical status in the fetus. 相似文献
12.
Edward A. Essock William K. Krebs James R. Prather 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,91(3):520-524
Summary The ability of humans to detect striated stimuli on the distal phalanges was found to be highly anisotropic. Observers were much more sensitive to stripes presented in the proximal-distal orientation than to stripes in any other orientation. This tactile anisotropy was contrasted with the well-known visual anisotropy in which sensitivity is greatest for stripes at the horizontal and vertical orientations. We suggest that both the tactile anisotropy and the visual anisotropy are caused by corresponding anisotropies in the distribution of preferred orientations of orientation-selective neurons with in the respective modalities. 相似文献
13.
Homologous intrauterine insemination (IUI) both in spontaneous and, preferably, in ovulation induction cycles, is widely recommended as the first choice of assisted conception techniques. However, there is no consensus on the effectiveness of such an approach. Especially in cases of male subfertility divergent views exist with regard to the therapeutic benefit. The literature survey presented is intended to provide information on the pregnancy rates achievable after homologous IUI for male-factor subfertility. For the sake of clarity, this review is limited to prospective, randomized IUI studies conducted since 1984, which clearly indicated that the work focused on male subfertility only as well as on either spontaneous cycles or cycles stimulated with a single regimen (clomiphene citrate or gonadotropins). We conclude from evidence-based data that IUI is justified as a reasonable first-line therapy in moderate male factor cases, especially if gonadotropins are used for mild ovarian stimulation. 相似文献
14.
Thirty-one combined transrectal ultrasonographic and urodynamic studies were performed in 24 patients with spinal cord lesions at different levels between C4 and T12. Ultrasonography provided accurate real-time imaging of the bladder neck, prostatic urethra and external sphincter during the bladder filling phase as well as during the voiding phase. Bladder and rectal pressures, sphincter EMG and uroflow were recorded simultaneously. Transrectal ultrasonography contributed significantly to the accuracy of diagnosing detrusor-sphincter dyssynergia. Sphincter contractions were clearly visualised with ultrasonographic video monitoring. This imaging method was especially helpful in sorting out the problems of 3 patients with poor emptying of bladder after endoscopic sphincterotomy. One had a urethral stricture and the other 2 had sphincters that opened adequately but bladders that emptied poorly because of detrusor hypocontractility. Other problems, such as benign prostatic hyperplasia and false passage, were also easily recognised. Transrectal ultrasonography not only provides accurate information but also involves no exposure to radiation and thus precludes the need for costly lead-shielded examination rooms. 相似文献
15.
16.
Calmodulin-stimulated cyclic nucleotide phosphodiesterase (PDE1C) is induced in human arterial smooth muscle cells of the synthetic, proliferative phenotype. 总被引:3,自引:0,他引:3
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S D Rybalkin K E Bornfeldt W K Sonnenburg I G Rybalkina K S Kwak K Hanson E G Krebs J A Beavo 《The Journal of clinical investigation》1997,100(10):2611-2621
The diversity among cyclic nucleotide phosphodiesterases provides multiple mechanisms for regulation of cAMP and cGMP in the cardiovascular system. Here we report that a calmodulin-stimulated phosphodiesterase (PDE1C) is highly expressed in proliferating human arterial smooth muscle cells (SMCs) in primary culture, but not in the quiescent SMCs of intact human aorta. High levels of PDE1C were found in primary cultures of SMCs derived from explants of human newborn and adult aortas, and in SMCs cultured from severe atherosclerotic lesions. PDE1C was the major cAMP hydrolytic activity in these SMCs. PDE expression patterns in primary SMC cultures from monkey and rat aortas were different from those from human cells. In monkey, high expression of PDE1B was found, whereas PDE1C was not detected. In rat SMCs, PDE1A was the only detectable calmodulin-stimulated PDE. These findings suggest that many of the commonly used animal species may not provide good models for studying the roles of PDEs in proliferation of human SMCs. More importantly, the observation that PDE1C is induced only in proliferating SMCs suggests that it may be both an indicator of proliferation and a possible target for treatment of atherosclerosis or restenosis after angioplasty, conditions in which proliferation of arterial SMCs is negatively modulated by cyclic nucleotides. 相似文献
17.
18.
Fatty acid composition of lipids of Escherichia coli W 1655 F+ and its stable protoplast type L-form
J. Gumpert W. Schade D. Krebs S. Baykousheva E. Ivanova As. Toshkov 《Journal of basic microbiology》1982,22(3):169-174
The comparative fatty acid analysis of extractable and non-extractable lipids of Escherichia coli W 1655 F+ and its stable protoplast type L-form shows quantitative as well as qualitative differences. From 10 different fatty acids obtained 16:0, 17:0, and 18:0 are present at about the same quantities in the lipid fractions of the bacterial and L-form. The absence of larger amounts of 12:0, 14:0, and 14:βOH fatty acids in non-extractable L-form lipids reflects the loss of the cell wall in L-form cells. 16:1 fatty acid was found in L-form lipids only. This qualitative difference and the 2–3 times higher content of 18:1 in L-form lipids and the 7 times lower content of cyc 19:0 in extractable lipids of the L-form may be interpreted as alterations characteristic for the changed composition of the cytoplasmic membrane in L-form cells. 相似文献
19.
Notch signaling regulates left-right asymmetry determination by inducing Nodal expression 总被引:1,自引:0,他引:1
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20.
Urs M Nater Elvira Abbruzzese Monika Krebs Ulrike Ehlert 《International journal of psychophysiology》2006,62(2):300-308
Although it is known that men and women differ in their music preferences and emotional reactions to music, little is known about sex differences in physiological reactions to music. In our study, we therefore set out to examine the differential reactivity to two musical stimuli that elicit distinct psychological and physiological reaction patterns. Fifty-three healthy subjects (mean age: 26.13, SD: 3.97; 26 males, 27 females) were examined. Heart rate, electrodermal activity, skin temperature, salivary cortisol, salivary alpha-amylase, and psychological variables were assessed during the course of the whole study. Following baseline assessment, two musical stimuli, which were carefully selected and rated in a pre-study as relaxing and pleasant (renaissance music) and arousing and unpleasant (heavy metal), respectively, were introduced. They were presented on two different days in a randomized order. Whereas psychological variables did not differ between men and women, results of electrophysiological measures indicate significantly different reactivity patterns between men and women. Women displayed elevated response curves to the arousing and unpleasant stimulus, whereas men did not. However, no differences were found with regards to endocrine measures in saliva. Our results demonstrate sex differences in reactivity patterns to musical stimuli in psychophysiological measures. In our study, we were able to show that women tend to show hypersensitivity to aversive musical stimuli. This finding is in accordance with previous literature on sex differences in emotion research. Furthermore, our study indicates that the confounding effects of sex differences have to be considered when using musical stimuli for emotion induction. 相似文献