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941.
An 84-year-old man complained of irritation of the left eye of several months' duration. He had had several previous surgical procedures including removal of bilateral pterygia and bilateral cataract extraction. Examination of the bulbar conjunctiva on the left eye disclosed a collection of cilia (eyelashes) located adjacent to the limbus at the 11:30-o'clock position. This aggregate of cilia was associated with irregular yellowish deposits 1.5 mm in diameter. The cilia and redundant conjunctival tissues were surgically excised. Histopathologic examination showed a botryomycotic granule surrounded by a prominent acidophilic ring (Splendore-Hoeppli phenomenon). Gram stains demonstrated the presence of microcolonies of gram-positive cocci and gram-negative rods within the granule. We postulate that the entrapment of displaced cilia provided a nidus for the bacterial colonization forming the botryomycotic granule. To our knowledge, botryomycosis of the conjunctiva has not been reported previously. 相似文献
942.
SA Evans SM Turner BJ Bosch CC Hardy MA Woodhead 《Canadian Metallurgical Quarterly》1996,9(8):1601-1604
Sputum isolation of Pseudomonas aeruginosa (PA) is associated with extensive disease in bronchiectasis. It is not known, however, whether infection with P. aeruginosa is the result or the cause of severe disease. We compared spirometry in patients with bronchiectasis before and after infection with P. aeruginosa, with that of patients infected by other organisms. All patients (n=12) with chronic colonization by P. aeruginosa (PA group) were studied. These were compared with other patients with bronchiectasis with no isolations of P. aeruginosa (n=37, non-PA group). In the PA group, forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were lower than in the non-PA group. The PA group, however, also had lower values at the time of initial colonization with P. aeruginosa than the current values for the non-PA group. Change in FEV1 and FVC over time was faster in the PA group than in the non-PA group. Reduction of FEV1 and FVC over time in the PA group prior to P. aeruginosa colonization was intermediate, not being statistically different from either value above. Our results confirm the association of chronic P. aeruginosa colonization with poor lung function, but conclude that patients with bronchiectasis who become colonized by P. aeruginosa have poorer lung function when first colonized than those colonized by other organisms. Decline in lung function is faster in those chronically colonized by P. aeruginosa than in those colonized by other organisms. It is not clear whether chronic P. aeruginosa colonization causes an accelerated decline in lung function or whether it is simply a marker of those whose lung function is already declining rapidly. 相似文献
943.
AP Ford NF Arredondo DR Blue DW Bonhaus J Jasper MS Kava J Lesnick JR Pfister IA Shieh RL Vimont TJ Williams JE McNeal TA Stamey DE Clarke 《Canadian Metallurgical Quarterly》1996,49(2):209-215
Hereditary developmental abnormalities of the upper or lower limbs in humans are easily recognizable phenotypes that can be used in the mapping and cloning of genes involved in normal human development. We studied a large Indian pedigree (UR002) with an autosomal dominant triphalangeal thumb (TPT) and polysyndactyly (PSD). The abnormalities were present only in the upper limbs, and the phenotype was fully penetrant. The expression of the phenotype was variable and ranged from unilateral TPT to bilateral TPT, preaxial du-, tri-, or quadruplication of the thumb, or syndactyly of multiple thumbs. There were 112 affected individuals in the pedigree. Previous linkage analyses on apparently similar phenotypes have identified a locus at 7q36 [Heutink et al., 1994, Nature Genet 6:287-291; Tsukurov et al., 1994]. To map the gene responsible for the TPT-PSD in family UR002, we performed linkage analysis in DNA from 47 affected and 7 normal individuals. Marker D7S550, located at 7q36, yielded a maximum LOD score of 11.31 at theta = 0.00. Additional markers in the region also showed no recombination. These data indicate that the gene responsible for the hand abnormality in pedigree UR002 maps to the same region as that in previous pedigrees with similar phenotype. Further analyses of recombinants among all the linked families by using new polymorphic markers will narrow the critical genomic region and facilitate positional cloning of the elusive gene. 相似文献
944.
J Chen RL Zhu M Nakayama K Kawaguchi K Jin RA Stetler RP Simon SH Graham 《Canadian Metallurgical Quarterly》1996,67(1):64-71
The observation that delayed death of CA1 neurons after global ischemia is inhibited by protein synthesis inhibitors suggests that the delayed death of these neurons is an active process that requires new gene expression. Delayed death in CA1 has some of the characteristics of apoptotic death; however, candidate proapoptotic proteins have not been identified in the CA1 after ischemia. We studied the expression of Bax protein and mRNA, a member of the bcl-2 family that is an effector of apoptotic cell death, after global ischemia in the four-vessel global ischemia model in the rat and compared these results with the expression of the antiapoptotic gene bcl-2. Bax mRNA and protein are both expressed in CA1 before delayed death, whereas bcl-2 protein is not expressed. Bcl-2 protein expression, but not that of Bax, is increased in CA3, a region that is ischemic but less susceptible to ischemic injury. In the dentate gyrus, both Bax and bcl-2 proteins are expressed. The selective expression of Bax in Ca1 supports the hypothesis that Bax could contribute to delayed neuronal death in these vulnerable neurons by an independent mechanism or by forming heterodimers with gene family members other than bcl-2. 相似文献
945.
RL Goldstone 《Canadian Metallurgical Quarterly》1996,22(4):988-1001
According to the assumption of monotonicity in similarity judgments, adding a shared feature in common to 2 items should never decrease their similarity. Violations of monotonicity are not predicted by feature- or dimension-based models but can be accommodated by alignment-based models in which the parts of one compared display are placed in correspondence with the parts of the other display. In 2 experiments, evidence for nonmonotonicities is obtained that is generally consistent with the alignment-based model SIAM (similarity as interactive activation and mapping; R.L. Goldstone, 1994). The calculation of similarity in this model involves an interactive activation process whereby correspondences between the parts of compared displays mutually and concurrently influence each other. As SIAM predicts, the occurrence of nonmonotonicities depends on perceptual similarity of features and the duration of presented comparison. 相似文献
946.
Cervico-vaginal smears were quite difficult to accept when they were first introduced in France, during the fifties, probably due to a fear that cytology might replace surgical pathology, whereas both methods may develop close together. At last, bridging the gap was accomplished by the pathologists and, nowadays, a number of cytopathologists have been trained and have become quite clever. Obviously, clinicians cannot do without the method described by George N. Papanicolaou (the so-called Pap test). Although cervical carcinoma is the very one cancer that should have been eradicated, as complete recovery is the rule when the diagnosis is made in time, at the preinvasive stage of the tumor, in France it is still responsible for 2000 annual deaths. Systematical target population screening should be organized, as well as in other countries and should become one of the main priorities of health care control. 相似文献
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950.
Bosch F. Palmer G. Sallada C. Swan C. 《Selected Areas in Communications, IEEE Journal on》1984,2(6):992-999
The mechanical, optical, and electrical design leading to a reliable, high-performance, robust, and compact transmitter are described. Reliability considerations are of paramount importance in the design of undersea systems. Main features of the laser-fiber-monitor package and the light-feedback control strategy are outlined. The functions of the laser drive circuit, consisting of a low-speed feedback IC and a high-speed modulation IC are discussed. Access to multiple test points through an edge board connector permits automated tuning and reliability testing. The transmitter circuit can provide a 200-mA bias current, about double the expected end of life laser bias requirement, and 60-mA modulation current, double the typical value, with < 0.75-ns rise and fall time. The transmitter operates up to 800 Mbit/s, far beyond the TAT-8 bit rate of 295.6 Mbit/s. Transmitter redundancy is planned to meet the extreme reliability requirements for the transatlantic system. Up to four of the compact transmitters can be mounted per regenerator, thus providing as many as three redundant transmitters for improved system reliability. 相似文献