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91.
The renal clearance of creatinine was measured following orogastric administration in conscious dogs. Values of creatinine clearance were compared with simul taneously determined values of inulin clearance, when urine volume, glomerular filtration rate and volume status were acutely altered by a variety of experimental manoeuvres. At urine volumes greater than 20 μl. min?1 · kg?1, creatinine clearance was not significantly different from inulin clearance. At low urine volumes there was some evidence of creatinine reabsorption. It is concluded that the bolus creatinine technique provides reliable estimates of glomerular filtration rate and is particularly applicable to long-term studies in conscious dogs.  相似文献   
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Using a triple wavelength (670 nm, 785 nm, 843/884 nm) scanning laser-pulse mammograph we recorded craniocaudal and mediolateral projection optical mammograms of 154 patients, suspected of having breast cancer. From distributions of times of flight of photons recorded at typically 1000-2000 scan positions, optical mammograms were derived displaying (inverse) photon counts in selected time windows, absorption and reduced scattering coefficients or total haemoglobin concentration and blood oxygen saturation. Optical mammograms were analysed by comparing them with x-ray and MR mammograms, including results of histopathology, attributing a subjective visibility score to each tumour assessed. Out of 102 histologically confirmed tumours, 72 tumours were detected retrospectively in both optical projection mammograms, in addition 20 cases in one projection only, whereas 10 tumours were not detectable in any projection. Tumour contrast and contrast-to-noise ratios of mammograms of the same breast, but derived from measured DTOFs by various methods were quantitatively compared. On average, inverse photon counts in selected time windows, including total photon counts, provide highest tumour contrast and contrast-to-noise ratios. Based on the results of the present study we developed a multi-wavelength, multi-projection scanning time-domain optical mammograph with improved spectral and spatial (angular) sampling, that allows us to record entire mammograms simultaneously at various offsets between the transmitting fibre and receiving fibre bundle and provides first results for illustration.  相似文献   
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Zusammenfassung Die umfassende Abrechnung mittels Fallpauschalen führt zu einer fundamentalen Änderung des deutschen Krankenhauswesens. Die behandelnden Ärzte übernehmen eine Schlüsselposition bei der Abrechnung stationärer Leistungen. Wir haben retrospektiv untersucht, welchen Einfluss veränderte Organisationsstrukturen auf die Qualität der Falldokumentation in einer Universitätskinderklinik haben. Die Einrichtung einer dezentralen Kontrollinstanz (DRG-Oberärzte) innerhalb der Kinderklinik—unterstützt von einem zentralen Medizinischen Controlling—führte zu einer deutlichen Besserung der Kodierqualität. Wir halten die Institution des DRG-Oberarztes für ein probates Mittel, um eine hohe Kodierqualität zu gewährleisten.
Abkürzungen DRG diagnosis related group - ICD international statistical classification of diseases and related health problems - ICPM international classification of procedures in medicine - OPS 301 Operationsschlüssel nach §301 SGB V - PCCL patients clinical complexity level  相似文献   
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BACKGROUND AND AIMS: Postoperative ileus is a common and poorly understood problem of abdominal surgery. The aim of this study was to measure postoperative intestinal transit and to evaluate bowel wall perfusion by a novel in vivo indocyanine green (ICG)-fluorescence measurement following intestinal manipulation (IM). METHODS: Rats underwent a simple intestinal manipulation. Myeloperoxidase-positive cells in the muscularis were stained with the Hanker-Yates reaction and quantified histochemically. Bowel wall perfusion was determined directly and 24 h postoperatively using a laser-fluorescence detection unit. Intestinal transit was visualized 24 h after IM. RESULTS: IM resulted in a massive infiltration (155-fold) of neutrophils into the intestinal muscularis 24 h postoperatively. Bowel wall perfusion significantly decreased directly and 24 h following surgery (29 and 59%, respectively). Gastrointestinal transit was similarly impaired and showed a reduction to 40% of the control values 24 h after IM. CONCLUSION: IM of the rat small intestine caused an impairment in bowel wall perfusion and microcirculation and a significant decrease in gastrointestinal transit. The ICG fluorescence measurement using the described system proved to be a simple and reliable method to evaluate intestinal transit and bowel wall microcirculation in vivo.  相似文献   
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Rationale The social interaction test is a valuable behavioural model for testing anxiolytic drugs in rodents, quantifying the level of social behaviour between pairs of rats.Objective The aim of the present study was to assess the appropriateness of the social interaction test for use with a Sprague–Dawley rat line, because of increasing use of this strain in targeted mutagenesis research.Methods Sprague–Dawley and Wistar rats received either diazepam or mCPP or were exposed to different environmental conditions (lighting, social isolation prior testing, habituation, testing-time). General anxiety-related parameters measured were: duration of active social contact, frequency of active social contact, latency to first contact. Different forms of active social contact were recorded: number of crawls, follows and sniffs. Secondly, aversion-induced hippocampal serotonin release and serotonin content in brain regions were measured.Results In Wistar rats habituation to the test substantially increased the time of social contact, an effect comparable with treatment with diazepam (1 mg/kg), whereas changes in the lighting level had less impact. Latency to the first contact increased under anxiety-reducing conditions, the frequency of contacts did not change consistently. Sprague–Dawley rats behaviour did not change under varying environmental conditions, and treatment with diazepam had only sedating effects at higher doses (5 mg/kg). Anxiogenic doses of mCPP caused reduced social interaction in both strains. Serotonin release and serotonin content were higher in the anxious Wistar rats.Conclusions Different rat strains as well as differing test conditions have a major impact on the outcome of this animal test for anxiety.  相似文献   
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From cultures of Mycogone cervina, a mycophilic fungus growing on the fruit bodies of ascomycete Paxina acetabulum, two new peptaibols (cervinin, N-Ac-Leu-Aib-Pro-Aib-Leu-Aib-Pro-Ala-Aib-Pro-Val-red-Leu (1) and the red-Leu O-acetylated derivative 2) were isolated. The structures of 1 and 2 were elucidated by spectroscopic techniques. They exhibited weak antibacterial as well as cytotoxic activities. They are the first secondary metabolites described from M. cervina.  相似文献   
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