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221.
The postoperative blind-loop syndrome can occur after side-to-side, end-to side or by-pass anastomoses of the gut and presents clinically as malabsorption syndrome. Pathogenetically, stasis or slowing of the bowel movements will cause a rapid increase of pathogenic bacteria in the small intestine. Malabsorption is characterized by 3 symptoms: Loss of weight, anemia, steatorrhoea. The method of choice for therapy is to perform a new, end-to-end, anastomosis of the intestine in order to re-establish a physiological situation. During the last 6 years 14 patients with malabsorption syndromes of varying degrees were operated upon: 6 had pure small intestinal anastomoses, 7 anastomoses between the small and large intestine and 1 patient had a side-to-side sigmoidal anastomosis. In all patients the side-to-side or by-pass anastomoses could be reversed.  相似文献   
222.
Photorealistic Scene Reconstruction by Voxel Coloring   总被引:16,自引:6,他引:16  
A novel scene reconstruction technique is presented, different from previous approaches in its ability to cope with large changes in visibility and its modeling of intrinsic scene color and texture information. The method avoids image correspondence problems by working in a discretized scene space whose voxels are traversed in a fixed visibility ordering. This strategy takes full account of occlusions and allows the input cameras to be far apart and widely distributed about the environment. The algorithm identifies a special set of invariant voxels which together form a spatial and photometric reconstruction of the scene, fully consistent with the input images. The approach is evaluated with images from both inward-facing and outward-facing cameras.  相似文献   
223.
OBJECTIVE: To study the mechanisms underlying recovery from middle cerebral artery infarction in 7 patients with an average age of 53 years who showed marked recovery of hand function after acute severe hemiparesis caused by their first-ever stroke. INTERVENTIONS: Assessment of motor functions, transcranial magnetic stimulation, somatosensory evoked potentials, magnetic resonance imaging, and positron emission tomographic measurements of regional cerebral blood flow during finger movement activity. RESULTS: The infarctions involved the cerebral convexity along the central sulcus from the Sylvian fissure up to the hand area but spared the caudate nucleus, thalamus, middle and posterior portions of the internal capsule, and the dorsal part of the precentral gyrus in each patient. After recovery (and increase in motor function score of 57%, P<.001), the motor evoked potentials in the hand and leg muscles contralateral to the infarctions were normal, whereas the somatosensory evoked potentials from the contralateral median nerve were reduced. During fractionated finger movements of the recovered hand, regional cerebral blood flow increases occurred bilaterally in the dorsolateral and medial premotor areas but not in the sensorimotor cortex of either hemisphere. CONCLUSIONS: Motor recovery after cortical infarction in the middle cerebral artery territory appears to rely on activation of premotor cortical areas of both cerebral hemispheres. Thereby, short-term output from motor cortex is likely to be initiated.  相似文献   
224.
FNA smears from six histologically documented cases of tubular adenoma of breast were critically analysed and compared with 10 histologically confirmed cases of fibroadenoma (five pericanalicular and five intracanalicular). Initially a cytological diagnosis of tubular adenoma was rendered only in one case. On review, two cases could be characterized as tubular adenoma, while the findings were suggestive in two others. The features helpful in diagnosis of tubular adenoma were the presence of benign ductal cells as three-dimensional cohesive balls and tubular structures in highly cellular smears. Stroma was conspicuously scanty or absent. Myoepithelial cells were present along with sheets of ductal cells as well as bipolar naked nuclei. Confusion with fibroadenoma occurred in two cases due to presence of a stag-horn pattern of ductal cells.  相似文献   
225.
Polyhydroxyalkanoates (PHAs) are biopolymers accumulated by a diversity of bacterial strains as carbon and energy reserve when grown under unbalanced nutritional conditions. Among the wide spectrum of applications for these biopolymers, the generation of nano and microparticles has drawn huge attention. PHA nanoparticles showed a high surface-to-volume ratio that makes them interesting for pharmaceutical uses. Bacteria from the Halomonas genus became interesting tools for biopolymer production in the last years, due to its metabolic plasticity that allows them to grow in a wide spectrum of compounds and salt concentrations. Halomonas titanicae KHS3 was previously isolated based on their ability to grow using aromatic hydrocarbons as the sole carbon source. In this work, the novelty lies in the evaluation of PHA accumulation by H. titanicae KHS3. Accumulation was successfully observed and thoroughly characterized on various carbon sources. Irrespective of the carbon source employed for growth, our experimental conditions consistently yielded PHB as the sole material identified. The truly intriguing aspect of this study is that PHB solutions in glacial acetic acid demonstrated exceptional suitability for electrospraying processing. This groundbreaking development led to the creation of nanoparticles with unique characteristics that hold immense promise for a wide range of applications.  相似文献   
226.
Determination of the minimum inhibitory concen-trations (MIC) of 212 common soap fragrance raw materials demonstrated that the paper disc-petri plate technique does not reflect the relative anti-microbial activity of these materials. Commonly used soap bacteriostats were shown to be 100 to 1000 times more effective than the most active fragrance materials. Of 521 fragrance materials initially screened by the petri plate method, 44% were inhibitory against one of the three test organisms, and 15% were effective against all three(Staphylococcus aureus, Escherichia coli, Candida albicans). Of a selected number (212) of these positive materials, subsequently screened against a lipophilic diphtheroid organism(Corynebacterium sp.), 64 materials (30%) were positive against all four test organisms. However, only nine materials (4%) had a MIC as low as 50 ppm compared to the common soap bacteriostat TCC, which had a MIC of 0.08 ppm (vs.S. aureus). In hand-degerming tests, no reduction of bacterial counts was obtained with a soap containing the most active fragrance materials. These results demonstrate that creation of a practical antimicrobial soap fragrance does not appear to be possible. 1Preliminary report presented at the 1976 national meeting of the American Chemical Society, Miami Beach, FL, September 1978.  相似文献   
227.
228.
We present the optical design and realization of a low-resolution liquid-crystal (LC) Fourier-transform spectrometer (FTS). This FTS is based on a polarization interferometer that has a Wollaston prism made of a LC material as a key component. It has a compact design, a good acceptance angle, and low temperature dependence and can be fabricated with cost-effective LC technology. Because the LC is polymerized, it is robust, and the temperature dependence is drastically reduced. The performance of a compact handheld version of the spectrometer and the characteristics (angular dependence, resolution, stray light, and temperature dependence) will be discussed.  相似文献   
229.
In this paper, we present a new kind of mobile ad hoc application, which we call mobile profile based distributed grouping (MoPiDiG), which is a combination of mobile clustering and data clustering. In MoPiDiG, each mobile host is endowed with a user profile and, while the users move around, hosts with similar profiles are found and a robust mobile group is formed. The members of a group are able to cooperate with each other or attain a goal together. In this article, MoPiDiG is defined and compared with related approaches. Furthermore, a modular architecture and algorithms are presented to build arbitrary MoPiDiG applications.
Christian SeitzEmail:
  相似文献   
230.
User-Oriented performance measurements on the ARPANET   总被引:2,自引:0,他引:2  
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