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71.
An unusual case of encephalomyeloneuritis associated with germ cell tumor with mature and immature teratoma arising in the mediastinum is presented. There was an unusually long interval from the onset of neurologic symptoms to the development of malignancy. The histopathology, characterized by limbic encephalitis, brain stem encephalitis, cortical cerebellar degeneration and myeloneuritis, was similar to that of paraneoplastic encephalomyeloneuritis previously described in the literature. Virological and immunological studies failed to demonstrate any causative agents or autoantibodies reacting with brain tissue. The causal relationship between the malignant neoplasm and encephalomyeloneuritis thus seems to be very complex.  相似文献   
72.
This study investigated the clinical characteristics of ciprofloxacin-resistant Proteus mirabilis isolates from urine samples associated with nosocomial infection or colonisation, and identified the risk-factors for ciprofloxacin resistance. Data for patients with ciprofloxacin-resistant P. mirabilis isolates (n=13) were compared with those for randomly selected patients with ciprofloxacin-susceptible P. mirabilis isolates (n=40) who were matched by temporal occurrence as control patients. The majority of ciprofloxacin-resistant P. mirabilis isolates were multiresistant, and ciprofloxacin resistance was associated significantly with previous use of fluoroquinolones and production of extended-spectrum beta-lactamases.  相似文献   
73.
74.
To isolate Babesia equi genes encoding immunodominant proteins, a cDNA expression library prepared from B. equi mRNA was immunoscreened with B. equi-infected horse serum. Eighteen positive cDNA clones were obtained, and the clone that showed the strongest immunoreactivity, designated Be82, was further characterized. The Be82 gene consisted of 1,953 bp and contained a partial open reading frame lacking the 5'-terminal sequence. As shown by Western blot analyses, immune sera from mice intraperitoneally injected with the Be82 gene product recognized the 82- and 52-kDa proteins of B. equi but not those of Babesia caballi. The glutathione S-transferase fusion protein expressed in Escherichia coli that was purified and used as the antigen in the enzyme-linked immunosorbent assay reacted specifically with B. equi-infected horse sera. These results suggest that the Be82 gene product is a potential diagnostic antigen candidate in the detection of B. equi infection in horses that will be useful both in the performance of epidemiological studies and in the granting of quarantine passes.  相似文献   
75.
The Raman spectra of solutions of poly(N-vinyl-2-pyrrolidone) (PVP; M?w = 1 000, 10 000, 40 000 and 360 000) in D2O and dimethyl sulfoxide (DMSO) were measured at various concentrations. PVP is hydrated by D2O in a manner different from N-ethyl-2-pyrrolidone (NEP) and N-methyl-2-pyrrolidone (NMP), monomer analogues of PVP. The self-association of DMSO molecules in the solution of PVP was found to be different from that in the solution of NMP by using difference spectroscopy. These phenomena were attributed to a net-like structure of concentrated solutions of PVP.  相似文献   
76.
In order to demonstrate the ultrastructural localization of the alpha-subunit of human chorionic gonadotropin (hCG) in the stomach mucosa, an immunoelectron microscopic study was performed using formalin-fixed specimens. In pyloric glands, alpha hCG-positive granules were irregular in outline, with a mean area and maximum diameter of 2,857 x 10(4) nm2 and 218.4 nm, respectively. In fundic glands, the granules had a smoother outline and were larger in both area and maximum diameter (3,943 x 10(4) nm2, 246.8 nm) than those of pyloric glands (p less than 0.001). In the atrophic fundic glands of non-antral gastritis, the alpha hCG granules showed a difference in shape; more elliptical granules appeared to be increased, as indicated by the higher value of the axial ratio (1,452) and lower value of D (1,862) (log10 area alpha D.log10 perimeter) compared with those in pyloric (1,231, 1,968) and fundic glands (1,148, 1,979) (p less than 0.001). The alpha-subunit of hCG is thus incorporated into different types of endocrine cell in pyloric and fundic glands, and the granule morphology appears to differ in hyperplastic alpha hCG cells of non-antral gastritis.  相似文献   
77.
The authors present an immunohistochemical analysis of tissue from five cases of morphologically distinctive Ewing's sarcoma in bone and soft tissue. The mean age of the five patients was 16.6 years, with a range of 6-28 years. The tumors existed in chest wall, pelvis, and lower extremities. Two siblings with tumor in bone were clinically diagnosed as having Ewing's sarcoma. All cases had immunoreactivity for neuron-specific enolase (NSE), and four cases revealed positive staining for Leu-7. Neuron-specific enolase is highly specific for neurons and neuroendocrine cells. In addition, immunoreactivity for Leu-7, expressing a natural killer activity, has been demonstrated in peripheral nerve fibers and neuroendocrine cells. The authors suggest that NSE and Leu-7 immunoreactive small round-cell neoplasm is probably a primitive neuroectodermal tumor and should be categorized as Ewing's sarcoma in bone and soft tissue.  相似文献   
78.
We examined the effects of anteroposterior movement of a sled on human upright standing. Each of six healthy men stood on the platform of a sled in the dark. The sinusoidal acceleration was provided, from 0.02 to 0.04 G, followed by 0.06 and 0.08 G, at a stroke length from 6 to 10 m and then to 14 m. Low acceleration (0.02 and 0.04 G) induced body sway, pivoting on the ankle joint. High acceleration (0.06 and 0.08 G) increased body sway, but the head-neck joint remained locked upright. The electromyographic recordings of the lower leg muscles revealed continuous tonic EMG activities of the gastrocnemius and tibialis anterior muscles at acceleration of 0.02 and 0.04 G, while reciprocal activation was observed at 0.06 and 0.08 G. During head movement, the neck muscles were slightly activated tonically at acceleration of 0.02 and 0.04 G, but they were markedly and tonically activated at 0.06 and 0.08 G. We speculate that the sled oscillation caused body sway in proportion to the acceleration, with the ankle joint playing a principal role. Analysis of neck movement also revealed that the head was held in a fixed upright position, indicating that the vestibulocollic reflex might tonically activate the neck muscles.  相似文献   
79.
To demonstrate unbalanced distribution of subunits of human chorionic gonadotropin (hCG) in the lung and lung tumors and to clarify its significance in differentiation and carcinogenesis of the lung, immunohistochemistry was performed on human fetus, infant, and adult lungs, and endocrine and nonendocrine tumors of the lung. Tissues were immunostained for alpha-subunits and for beta-subunits of glycoprotein hormones (hCG, luteinizing hormone, follicle stimulating hormone, and thyroid stimulating hormone), serotonin, and gastrin-releasing peptide. Immunoreactive alpha-subunit was first identified in endocrine-like cells at the 39th gestational week, and was found in all infant lungs and two-thirds of adult lungs. The hCG beta-immunoreactive cells were extremely rare in an adult lung, and were not found in fetus or infant lungs. The alpha-subunit-containing cells were present in neuroepithelial bodies, tumorlets, carcinoid tumors, and small cell carcinomas of the lung (SCCL). There were occasionally alpha-subunit-containing cells in non-SCCL but one of the carcinomas also contained many serotonin-positive and gastrin-releasing peptide-positive cells in the same region. All alpha-subunit-immunoreactive cells lacked immunoreactivity for beta-subunits of glycoprotein hormones, except some for hCG beta in one carcinoid tumor. Immunoreactive cells for isolated hCG beta appeared much more frequently in non-SCCL than in SCCL. Most non-SCCL containing hCG beta-positive cells did not show alpha-subunit-immunoreactivity. Thus, immunohistochemical distribution of hCG-subunits was unbalanced and hCG-subunits may be expressed through an independent mechanism, commonly in the lung and lung tumors. The significance of isolated alpha-subunit is further discussed in light of multidirectional differentiation of lung neoplasms (14, 17).  相似文献   
80.
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