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81.
AIM: The aim of the study is to analyse the benefits and risks of PEE in patients, cared for by a team with many years experience. PATIENTS AND METHODS: From 16. 2. 1988 until 31. 12. 1993 246 PEEs (229 gastrostomies, 6 duodenostomies, 7 jejunostomies, 4 attempts) were performed on 234 patients (56% male, 44% female, mean age 68.3 years). 117 patients had tumorous and 117 neurological diseases. We used the pull technique with the Fresenius Freka PEG-system. Analysis was performed using a standardised documentation sheet which was filled out until the end of tube feeding. In total, we registered 39,678 days of tube feeding, 4513 of which were in hospitalized patients. RESULTS: The mean intubation time was 192.6 days (maximum 1496). In 8 cases, the tube could be explanted before the patient was discharged; 68 patients were discharged to a nursing home and 71 patients were allowed to go home. The tube-independent hospital lethality was 36.64%. A PEE-specific lethality had not been registered. Complications arose in a total of 37 patients (15.04%), 4 of which were severe (1.63%) Fifty-nine patients (25.43%) reported short-term feelings of ill health (vomiting, diarrhoea, pain). CONCLUSION: PEE is an effective and low-risk method of long-term nutrition. The advantages are simple insertion, safe handling by patients and relatives/nursing staff and the low cost.  相似文献   
82.
The purpose of this study is to determine whether left ventricular dysfunction following coronary artery spasm by 123I-BMIPP myocardial imaging. To reveal the clinical efficacy of 123I-BMIPP SPECT, 20 patients with vasospastic angina were studied using resting, 3-hour delayed image with 123I-BMIPP and exercise, 3-hour delayed image with 201Tl SPECT. 123I-BMIPP uptake was decreased compared to 201Tl (discordant) in 12 patients (60%) and in 49/100 myocardial segments (49%). The extent and severity score in resting image with 123I-BMIPP were significantly larger than that in delayed image with 201Tl (p < 0.01). In 123I-BMIPP SPECT, the severity score in the latest ischemia were significantly larger than that in others. The incidence of a complete agreement of decreased 123I-BMIPP uptake and coronary artery spasm was significantly higher (75%) than that in 201Tl (28%, p < 0.01). Furthermore, compared to 201Tl uptake, decreased 123I-BMIPP uptake much more corresponded to reduced wall motion in 9 of patients with mismatching. The severity of regional wall motion abnormality was significantly correlated with severity score of 123I-BMIPP. Late redistribution in delayed image with 123I-BMIPP was seen in 6 patients. The regional washout rate and the severity of regional wall motion abnormality in 6 patients was significantly lower than that in others (p < 0.05). Thus, metabolic abnormality assessed by 123I-BMIPP is well associated with left ventricular asynergy and spastic region in patients with vasospastic angina. In conclusion, 123I-BMIPP SPECT may sensitively delineate the impaired myocardium following coronary artery spasm, and it is very useful in diagnosing and estimating the severity of vasospastic angina.  相似文献   
83.
84.
We investigated retrospectively 132 cases of open wedge high tibial osteotomy using an external fixation device, concentrating on the rate of neurological complications. One group of patients underwent surgery according to the conventional technique (n = 89). The rate of transient neurological complications was 15.7%; 7 months after surgery the rate of persistent deficits was 12.4%. For the second group (n = 43) a modified surgical technique was used that lowered the complication rate significantly (transient deficits 14%, persistent deficits 4.7%). In the modified technique the osteotomy is not performed in the conventional way using an oscillating saw but through consecutive drill holes of increasing diameter followed by osteoclasis. The lower complication rate in the second group is mainly due to the less extensive approach that leads to a smaller number of postoperative tibialis anterior syndromes (type B lesion). No differences were found with type C lesions (extension deficit of D1). No complete peroneal nerve palsy (type A) occurred in either group. We conclude that the reduction of neurological complications in group 2 is related to the less extensive approach of the proposed technique.  相似文献   
85.
The self-bias potential (Vdc) induced on an RF-powdered electrode (153 mm Ø) in a plasma is measured using electrical probes which are buried in, de-insulated from, and RF-connected to the electrode. The configuration of the probes allows to study the distribution of Vdc discretely on the electrode. The potential is homogeneous in the absence of external magnetic field. In the presence of a homogeneous magnetic field parallel to the electrode, it is reduced and a monotonous gradient takes place in its distribution due to the plasma shift induced by E × B drift. When the magnetic field is rotated along the axis of the RF-electrode at a frequency less than 50 Hz, the distribution, which is almost identical to the one in a static field, rotates with the magnetic field. On the coordinate system rotating with the magnetic field, the probes are regarded to be rotating. The potential distribution is obtained as a continuous function of the azimuthal angle. Thus the rotation of the field provides information for the experimental interpolation.  相似文献   
86.
A technique for SiO2 formation by liquid-phase deposition (LPD) at nearly room temperature for low-temperature processed (LTP) polysilicon thin-film transistor (poly-Si TFT) was developed. LPD SiO2 film with a lower P-etch rate shows a dense structure. LPD SiO2 also exhibits good electrical characteristics. LTP poly-Si thin-film transistors (TFTs) with LPD SiO 2 as the gate insulator have been fabricated and investigated. Their characteristics indicate performance adequate for their use as pixel transistors in liquid crystal displays (LCDs)  相似文献   
87.
For the first time, the surface metal on nonalloyed ohmic electrodes is found to significantly change the profiles of gate grooves, when resist openings are employed to monitor drain current during wet-chemical gate recess for sub-micron InAlAs/lnGaAs heterojunction field-effect transistors (HFETs). The surface metal of Ni enhances the etching rate in comparison with that in the absence of electrodes by a factor of 4 and 10, laterally and vertically, which is favorable to fabricate deep gate grooves with small side etching. The Pt surface metal, however, leads to preferential etching of InGaAs over InAlAs, which can be useful to realize large side etching. The existence of an electrochemistry-related etching component, which arises when the ohmic electrodes are present during recess etching, is considered to be responsible for these behaviors  相似文献   
88.
Learning long-term dependencies with gradient descent is difficult   总被引:12,自引:0,他引:12  
Recurrent neural networks can be used to map input sequences to output sequences, such as for recognition, production or prediction problems. However, practical difficulties have been reported in training recurrent neural networks to perform tasks in which the temporal contingencies present in the input/output sequences span long intervals. We show why gradient based learning algorithms face an increasingly difficult problem as the duration of the dependencies to be captured increases. These results expose a trade-off between efficient learning by gradient descent and latching on information for long periods. Based on an understanding of this problem, alternatives to standard gradient descent are considered.  相似文献   
89.
90.
Combination therapies that include metronidazole (MTZ) are the most successful therapies used in eradicating Helicobacter pylori. In this study, the prevalence and the relevance of heterogeneity in susceptibility to MTZ among H. pylori populations of 156 patients were evaluated. The results of this study show that 37 patients (24%) were infected with MTZ-resistant H. pylori (MIC > or = 8 micrograms/ml). Furthermore, 33% (52 of 156) of the patients were found to be infected with H. pylori populations heterogeneous for their susceptibility to MTZ. The reassessment of the MICs of MTZ for these 52 H. pylori populations revealed MTZ resistance in 28 of them, increasing the number of MTZ-resistant H. pylori populations among the 156 patients to 65 (42%). Out of 20 isolates, 2 (10%) heterogeneous in their susceptibility to MTZ also appeared to be heterogeneous at the genome level as determined by randomly amplified polymorphic DNA fingerprinting. In conclusion, the results show the limitations and risk of possible misinterpretations when only a single colony, picked from the primary H. pylori populations isolated from patients, is analyzed for its susceptibility to MTZ.  相似文献   
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