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11.
Differential Stripping: Determination of the Amount of Topically Applied Substances Penetrated into the Hair Follicles
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Alexa Teichmann Ute Jacobi Michael Ossadnik† Heike Richter Stefan Koch† Wolfram Sterry Jürgen Lademann 《Journal of general internal medicine》2005,20(5):264-269
The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively. 相似文献
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Dr. med. Dipl.-Soz. T. Krones E. Schlüter S. El Ansari T. Wissner R. Zoll G. Richter 《Gyn?kologische Endokrinologie》2004,2(4):245-250
Preimplantation genetic diagnosis (PGD) has been vigorously debated in Germany ever since the Bundesärztekammer (BÄK) published a draft of guidelines for PGD in March 2000. Many stakeholders such as churches, medical societies, and diverse associations have participated in the discussion. However, little is known about the attitudes of experts, directly affected patient groups, and the public in Germany. In several studies that are part of the German research program on ethical implications of the Human Genome Project, representative surveys were undertaken to assess the attitudes of the general population (n=1017), five relevant expert groups (n=879), and couples at high risk for genetic disorders(n=324) towards PGD and prenatal diagnosis (PD). All groups favor legislation for PGD. Differences exist in regard to the extent of their approval. For 17% of the high-risk couples with a persisting desire for a child, PGD performed in a neighboring country is the most probable reproductive option. These results should be carefully considered in the ongoing legislation process on human reproduction in our country. 相似文献
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Boerhaave’s syndrome: Primary repair vs. esophageal resection—Case reports and meta-analysis of the literature 总被引:3,自引:0,他引:3
Otto Kollmar M.D. Werner Lindemann M.D. Sven Richter M.D. Ingo Steffen M.D. Georg Pistorius M.D. Martin K. Schilling M.D. 《Journal of gastrointestinal surgery》2003,7(6):726-734
Boerhaave’s syndrome is a life-threatening disease with a high mortality. With regard to the heterogeneity of treatment strategies,
no comparative studies exist and recommendations remain controversial. Seventeen cases of Boerhaave’s syndrome operated on
between 1989 and 2000 at our hospital were reviewed retrospectively to compare the time period between perforation and diagnosis,
and the morbidity and mortality among the different treatment options. In addition, we conducted a meta-analysis of the literature
including all series containing five or more patients and compared the findings with our own data. Our patients with a perforation
history of less than 12 hours showed significantly fewer signs of sepsis compared to patients with a history of more than
12 hours. In a comparison of patients with primary repair vs. patients treated with esophageal resection or an exclusion operation,
no differences were found. In the literature, patients with a long period of perforation (more than 24 hours) were treated
more often with an esophageal resection than patients with primary repair. In cases of Boerhaave’s syndrome, primary suturing
of the esophageal perforation should be reserved only for those patients presenting within 12 hours after perforation. In
all other cases, depending on the extent of the tissue damage, a two-stage esophageal resection with cervical esophagostomy
and gastrostomy is recommended as the safest treatment. 相似文献
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Helmut Seidel Barbara Harazin Kristina Pavlas Christine Sroka Jörg Richter Ralph Blüthner Udo Erdmann Jan Grzesik Barbara Hinz Reinhard Rothe 《International archives of occupational and environmental health》1988,61(1-2):95-106
Summary This study was carried out in order: (1) to examine the effects of isolated and combined prolonged exposures to noise and whole-body vibration on hearing, vision and subjectively experienced strain, and (2) to check the combined effects with repeated exposures. Six male subjects were exposed twice to noise (N) at 92 dBA, whole-body vibration (V) in the Z-axis at 4 Hz and 1.0 ms–2 rms, and noise and vibration (NV) for 90 min with each condition. Temporary threshold shifts of hearing (TTS) and their integrals (ITTS) were measured at 4, 6, 10, and 12 kHz. Visual acuity was examined by means of a very sensitive test. Cross-modality matching (CMM) of the handgrip force was used to judge the subjectively experienced strain. NV induced a clear tendency of higher TTS and ITTS than N, with several significant differences most pronounced at 10 kHz. With repeated exposures, the effect of NV decreased, while the reactions to N and V remained unchanged. The individual reactions to NV differed. The influence of the duration of exposures on vision depended on the condition; N caused time-dependent changes, whereas V did not. CMM-data increased with the duration of the exposure during V and NV. N was generally judged to be more straining than V; NV caused higher strain than V during the first 30 min of exposure only. Correlations between different effects suggest certain links between them. Additionally, less motivation — daily obtained by a questionnaire — often correlated with higher ITTS during N and NV. The results also illustrate the combined effects on the individual susceptibility, repetition of exposure, the kind of response, and, possibly, the actual psychic state.Abbreviations CMM
cross-modality matching
- MVC
maximum voluntary contraction force
- N
exposure condition: noise level 92dBA, no whole-body vibration
- NV
exposure condition: combined exposure to noise with a level of 92 dBA and wholebody vibration with 4 Hz, 1 ms–2 rms
- V
exposure condition: whole-body vibration with 4 Hz, 1 ms–2 rms
- TTS
temporary threshold shift
- ITTS
integral of temporary threshold shift
- WBV
whole-body vibration in the common sense
This work was done in the Temporary International Research Team on Combined Effects of Noise and Vibration of the Council of Mutual Economic Assistance of the Socialist Countries. The authors gratefully acknowledge the help and assistance of L.-M. Brumm, Y. Bening, M. Godau, G. Weber, and R. Vizcaino. 相似文献
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. We invited Dr Peplau to provide a personal reflection on the recent history of psychiatric nursing and her thoughts on immediate challenges facing the profession. The paper is an individual scholar's commentary on the way that psychiatry has waxed and waned over the years, in relation to nursing. This historical review discovers and reports a challenge to current practice. Dr Peplau describes a professional shift that is pulling nurses toward the subordinate role observed earlier this century. The paper draws attention to how contemporary practice can be positively influenced, e.g., by giving a structure to the allocation and conduct of nurse–patient time. 相似文献
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Mycobacterium fortuitum NRRL B-8119 transformes sterols into 9 alpha-hydroxy-androsta-4-ene-3,17-dione (9OH-AD) at high efficieny. Cells strongly aggregate to the surface of the sterol particles forming stable agglomerates (“substrate immobilized cells”). Substrate uptake and product formation were studied as function of the size of the sterol particles. Using particle sizes comparable with the size of the mycobacterial cells (> 5μm) highest rates were found for both the substrate uptake and the product formation. After mechanical reinforcement of the contact between mycobacterial cells and the sterol substrate by co-grinding of the components, a significantly increased product formation was observed. Associated cells and cell-sterol agglomerates were investigated by freeze-fracture electron microscopy. The micrographs obtained demonstrate that cells of M. fortuitum are growing into the sterol microcrystallite. The uptake of the sterol substrate is assumed to take place via direct contact between cells and the substrate particles. To understand the transport mechanism a model is proposed that includes a flexible multicomponent mesophase (FMCM) which is placed between cells and particles and which mediates the sterol uptake. The putative FMCM is assumed to be composed of mycobacterial glycolipids, extracellular biolipids, synthetical detergents, sterol and water. 相似文献