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Summary Biotinylated neoglycoproteins are useful to determine the expression of sugar receptors (lectins) histochemically in routinely processed tissue sections. Assessment of the presence of distinct receptor classes with specificity to-galactosides and to- or-N-acetylgalactosamine, selected on the basis of their potential relevance for recognition processes within the metastatic cascade in murine model systems, was performed for a common human tumour type, colorectal cancer. The four different types of neoglycoproteins, derived from covalent attachment of commercially available derivatives of-N-acetylgalactosamine, differed only quantitatively in their capacity to detect specific binding on cultured cells and tissue sections, thus posing no major restriction on the choice of synthetic process for histochemical efficiency of the product. Glycocytological application revealed specific probe binding and a regulation of level of receptor expression for a human colon carcinoma cell line primarily forN-acetylgalactosamine-specific receptors upon retinoic acid-induced differentiation. Monitoring of sections of the 12 cases of primary and secondary colorectal lesions invariably disclosed the presence of the respective receptors, the extent of cell labelling in primary tumours and metastases being similar. Establishment of metastases, even in different target organs, is apparently not followed by a major phenotypic variation in this feature.  相似文献   
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Ticks are the vectors of many zoonotic diseases in the United States, including Lyme disease, human monocytic and granulocytic ehrlichioses, and Rocky Mountain spotted fever. Most known Bartonella species are arthropod borne. Therefore, it is important to determine if some Bartonella species, which are emerging pathogens, could be carried or transmitted by ticks. In this study, adult Ixodes pacificus ticks were collected by flagging vegetation in three sites in Santa Clara County, Calif. PCR-restriction fragment length polymorphism and partial sequencing of 273 bp of the gltA gene were applied for Bartonella identification. Twenty-nine (19.2%) of 151 individually tested ticks were PCR positive for Bartonella. Male ticks were more likely to be infected with Bartonella than female ticks (26 versus 12%, P = 0.05). None of the nine ticks collected at Baird Ranch was PCR positive for Bartonella. However, 7 (50%) of 14 ticks from Red Fern Ranch and 22 (17%) of 128 ticks from the Windy Hill Open Space Reserve were infected with Bartonella. In these infected ticks, molecular analysis showed a variety of Bartonella strains, which were closely related to a cattle Bartonella strain and to several known human-pathogenic Bartonella species and subspecies: Bartonella henselae, B. quintana, B. washoensis, and B. vinsonii subsp. berkhoffii. These findings indicate that I. pacificus ticks may play an important role in Bartonella transmission among animals and humans.  相似文献   
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AIMS: Cytogenetic data on solitary fibrous tumours (SFT) are very limited. We studied a benign pleural SFT for its ultrastructural and immunohistochemical details, and made cytogenetic analyses for comparison with other genetic and ultrastructural studies of SFT. RESULTS: Immunohistochemistry showed strong positivities for CD34 and vimentin, but no reactions with anti-cytokeratins and epithelial membrane antigens. Electron microscopy revealed primitive desmosomes in our SFT. The results thus evinced fibroblast-like cells with intermediate epithelial-mesenchymal character. Comparative genomic hybridization of the tumour revealed losses of 1p33-->pter, 17pter q21, entire copies of chromosomes 19 and 22, and gains of 1p21-p22, 2q23-q32.3, 3pl2-q13.2, 4p14-q28, 6p12-q21, 9p21-->pter and 13q21-q31. Furthermore, there was loss of 20q, as was previously reported elsewhere in a case of benign and a case of malignant SFT. CONCLUSIONS: The results furnish further evidence of the involvement of -20q in SFT. In addition, they show that SFT may have complex genomic imbalances and primitive features, despite having a benign appearance.  相似文献   
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Klinische und feinmotorische Therapiekontrolle bei Morbus Wilson   总被引:1,自引:0,他引:1  
At the time of diagnosis and after therapy, we examined 33 patients suffering from Wilson's disease. We applied a standardized diagnostic score system on the basis of clinical signs. Without observing any differences between pseudoparkinsonian and pseudosclerosis subtypes, patients with neurological symptoms significantly improved by 2.33 points. Patients with initially more severe symptoms showed the same improvement as less affected patients. Fine motor disturbances were evaluated using the V-scope system. Finger tapping and drawing a spiral were compared to values of a healthy control group (n = 52). Patients with neurological symptoms showed significantly decreased frequencies in both tests. The clinical score was related to frequencies in finger tapping but not in drawing a spiral. Therefore finger tapping can be used as an objective diagnostic tool to evaluate the severity of Wilson's disease, while spiral testing appears to be a sensitive screening tool.  相似文献   
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The increasing number of partial nephrectomies is accompanied by a higher incidence of rare iatrogenic vascular malformation. In the present case, an aneurysm with secondary arteriovenous (AV) fistula that developed after partial nephrectomy with a complicated course is described. The fistula was diagnosed during the sonographic follow-up in an asymptomatic patient. Due to the high flow rate of the shunt, the aneurysm was treated using open surgery.  相似文献   
8.
Most patients who die after traumatic brain injury (TBI) show evidence of ischemic brain damage. Nevertheless, it has proven difficult to demonstrate cerebral ischemia in TBI patients. After TBI, both global and localized changes in cerebral blood flow (CBF) are observed, depending on the extent of diffuse brain swelling and the size and location of contusions and hematoma. These changes vary considerably over time, with most TBI patients showing reduced CBF during the first 12 hours after injury, then hyperperfusion, and in some patients vasospasms before CBF eventually normalizes. This apparent neurovascular uncoupling has been ascribed to mitochondrial dysfunction, hindered oxygen diffusion into tissue, or microthrombosis. Capillary compression by astrocytic endfeet swelling is observed in biopsies acquired from TBI patients. In animal models, elevated intracranial pressure compresses capillaries, causing redistribution of capillary flows into patterns argued to cause functional shunting of oxygenated blood through the capillary bed. We used a biophysical model of oxygen transport in tissue to examine how capillary flow disturbances may contribute to the profound changes in CBF after TBI. The analysis suggests that elevated capillary transit time heterogeneity can cause critical reductions in oxygen availability in the absence of ‘classic'' ischemia. We discuss diagnostic and therapeutic consequences of these predictions.  相似文献   
9.
In order to evaluate the influence of the trailing edge of clicks on the auditory brain stem response (ABR) in normal ears, rarefaction and condensation step functions (RS and CS) compared to rarefaction and condensation clicks (RC and CC) at an intensity of 70 dB nHL were used. Significant intraindividual differences could be found for the latencies and amplitudes in the RS-CS, RS-RC and RC-CC comparison. However, the mean values of the complete group of test subjects showed no significant differences for the latencies and amplitudes, except the significantly greater amplitudes of wave I and II for R versus C step and R versus C click. Only a tendency to shorter latency for wave VI with R versus C step and click was revealed. These results show that there was no essential influence of the trailing edge of the used R and C clicks on the ABR. The latency of the ABR with excitation of the cochlea by step or click function seemed to be mainly determined by the internal oscillation sequence in the cochlea and not by the stimulus polarity.  相似文献   
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