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41.
The 13C-mixed triglyceride (13C-MTG) breath test (BT) is a safe and noninvasive method to measure exocrine pancreatic function. We examined the reproducibility of the 13C-MTG BT in a group of 17 healthy controls and 8 adult patients with cystic fibrosis (CF). In controls no statistically significant difference in percentage dose recovered (PDR) was found between the first and the second result of repeated tests: the mean values were 35.5 +/- 5.5 vs. 32.3 +/- 7.4 PDR (n = 17). Also in the group of CF patients (n = 8) no significant difference between duplicate tests was found: mean values 17.5 +/- 7.5 and 17.5 +/- 7.8 PDR, respectively. The coefficient of repeatability is 8 PDR for the controls and CF patients together. Two factors might influence the outcome of the test. First, individually measured CO2 excretion instead of the usually assumed 9 mmol/h/kg CO2 production might alter the result of the 13CO2-MTG BT. Therefore CO2 production was measured by indirect calorimetry in 12 healthy controls and 13 CF patients. Measured CO2 excretion was not significantly different between healthy controls and CF patients. Secondly, exercise might influence BT results due to its separate effects on both CO2 production and excretion. The influence of physical exercise at a level of 25 or 50 W was studied on a bicycle ergometer in 4 healthy controls during the last 5 min of each 30-min sampling period. Exercise gave lower test results, on average 85% of the PDR value at rest. Incidently, it was observed in 1 patient that use of 13C-enriched food during the day preceding the test caused inappropriately low test results in the 13C-MTG BT. The 13C-MTG BT is a test with a fair but less than desirable reproducibility. Test conditions should be standardized to eliminate confounding influences. Exercise should be limited or strictly defined. Diet on the day preceding the test should not contain naturally 13C-enriched food. There is no need to measure individual CO2 production.  相似文献   
42.
Hidradenitis suppurativa (HS) represents a chronic, recurrent, deep-seated folliculitis resulting in abscesses followed by the formation of sinus tracts and scarring. It is an uncommon disorder frequently involving the perianal region. We review the clinical and pathological features of 12 patients (10 men and two women) with perianal HS (PHS). The mean age at presentation was 43 years (range 24-65), and the mean duration of illness was 14 years (range 2-30). Two patients exhibited multiple areas of involvement, including the axilla and the nape of the neck, in addition to the perianal region. Histological examinations showed epidermis-lined sinuses surrounded by dense plasma cell infiltration in four of nine specimens. The complications related with PHS included anal fistula (seven patients), diabetes mellitus (four), malignant tumour (two) and sepsis (one). Three patients died of the complications. Eight patients underwent wide local excision. The defects were managed with a meshed split-thickness skin graft in five patients, and open treatment in the remainder. New lesions developed in untreated skin of two patients. However, no patient relapsed in the surgically treated sites. PHS is frequently complicated with anal fistula and is occasionally life-threatening as a result of the occurrence of malignant tumours or sepsis. Early surgical excision followed by meshed split-thickness skin graft can successfully cure the lesion without functional disturbance.  相似文献   
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Photosystem I (PSI) from Thermosynechococcus elongatus was immobilized on ITO by using vitamin K1 exchange with artificial molecular wires in PSI. A PSI-modified surface was prepared for observation of lateral TEM images to provide an understanding of its interfacial structure. This paper describes the use of an ultramicrotome to prepare ultra-thin (< 20 nm) sections of PSI on ITO substrates. Cross-sectional TEM and energy-dispersive X-ray spectrometry supported that monolayer PSI was attached to the ITO electrode.  相似文献   
46.
The characteristics of a detector fabricated using piezoelectric lead zirconate titanate (PZT) were studied by irradiating it with a 400 MeV/n xenon (Xe) beam while changing the beam flux intensity. The largest output signal was observed from the detector when the beam power per unit time was estimated to be largest. It was also found that the sensitivity per Xe ion of the detector seemed to be higher with decreasing the amount of the Xe ion flux within the limits of the experimental conditions.  相似文献   
47.
The photosynthetic bacterium Rhodobacter sphaeroides accumulates 5-aminolevulinic acid (ALA), which is a precursor in tetrapyrrole biosynthesis, under light illumination and upon addition of levulinic acid as an inhibitor of ALA dehydratase. To generate an industrial strain which produces ALA in the absence of light, we sequentially mutated R. sphaeroides CR-286 using N-methyl-N'-nitro-N-nitrosoguanidine (NTG). The mutant strains were screened by cultivating in the absence of light and assayed for ALA by the Ehrlich reaction in a 96-well microtiter plate. The mutant strain CR-386, derived from R. sphaeroides CR-286, was selected as a mutant that exhibited significant ALA accumulation. While CR-286 required light illumination for ALA production, CR-386 was able to accumulate 1.5 mM ALA in the presence of 50 mM glucose, 60 mM glycine, 15 mM levulinic acid and 1.0% (w/v) yeast extract under conditions of agitation in the absence of light. The mutant strain CR-450, derived from strain CR-386, was selected further as a mutant that exhibited significant ALA accumulation but no accumulation of aminoacetone, analogue of ALA. CR-450 accumulated 3.8 mM ALA under the same conditions. In the presence of 50 mM glucose, 60 mM glycine, 5 mM levulinic acid and 1.0% (w/v) yeast extract, the mutant strain CR-520, derived from strain CR-450, and strain CR-606, derived from strain CR-520, accumulated 8.1 mM and 11.2 mM ALA, respectively. In batch fermentation, the strain CR-606 accumulated 20 mM ALA over 18 h after the addition of glycine, levulinic acid, glucose and yeast extract.  相似文献   
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The gallbladder is perforated and stones are spilled more frequently during laparoscopic cholecystectomy than during open cholecystectomy. Recent reports have implicated spilled gallstones as a source of infrequent but serious complications of laparoscopic of laparoscopic cholecystectomy. They can cause serious morbidity, and in most cases the patient will require open surgery for management of these complications. The authors report the case of a patient who was ill for 14 months after laparoscopic cholecystectomy when spilled stones formed a nidus for intra-abdominal abscess and colocutaneous fistula. Every effort must be made to prevent gallbladder perforation. When it does occur, all stones should be retrieved. Attempts at repairing gallbladder perforations are often unsatisfactory. A simple solution to this potential problem is to retrieve all stones immediately, place them in an intraperitoneal specimen bag, and "park" the bag on the liver. As soon as the gallbladder is dissected off the liver it should be placed in the specimen bag with the stones and removed through the umbilical port opening.  相似文献   
50.
This paper deals with important practical problems related to vibration reduction in a circular saw used for wood cut-offs. An investigation is made of the static and dynamic characteristics of thin plate structures as a model of a circular saw, to obtain fundamental knowledge to improve circular saw performance. The circular saw is represented experimentally by a thin rectangular plate clamped by two shims. The bending rigidity and damping capacity of a structure are measured for six different clamping methods. The results are evaluated by a coefficient, which is introduced through Merritt's regenerative chatter vibration theory. The most effective thin plate structure is found to improve vibration-proof capacity. This structure is easily applicable to an actual circular saw.  相似文献   
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