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991.
To determine the risk of exposure to body fluids potentially contaminated with infectious organisms we instituted a prospective study of all urological procedures performed at our institution. Urological procedures were divided into 3 categories: open, cystoscopic and endoscopic surgical (transurethral resection of the prostate or bladder tumor, ureteroscopy and percutaneous procedures). We have complete data analysis on 594 consecutive patients who underwent an operation at our institution: 77 (13%) underwent an open procedure, 75 (13%) underwent an endoscopic surgical procedure and the remaining 442 (74%) underwent cystoscopic procedures. All procedures were performed by supervised house staff using universal precautions. The operating surgeon was exposed to potentially contaminated body fluids in 173 of 594 cases overall (29%). There was exposure in 17% of all open procedures, 41% of all endoscopic surgical procedures and 29% of all cystoscopic procedures. Urologists must consider themselves at high risk for exposure to potentially contaminated body fluids and take appropriate precautions.  相似文献   
992.
We performed neutron reflectivity measurements on deuterated polystyrene thin films supported on silicon substrate as a function of temperature. In order to see effects of annealing on the thickness, the films were annealed at 80 °C for 12 h and 135 °C for 12 h, termed weakly and strongly annealed films, respectively. One of the main purpose of this study is to see if the negative expansivity reported for very thin films [Phys. Rev. Lett. 71 (1993) 867] is caused by unrelaxed structure due to lack of annealing. It was found that the weakly annealed films show negative expansivity in the glassy state and it disappears for the strongly annealed films with thickness above about 90 Å. This suggests that the negative expansivity is due to the unrelaxed structure. In addition to this relaxation process, the thickness difference between the heating process and the cooling process suggests that there is another very slow relaxation process in thin films detectable at around 135 °C or about 32 °C above the glass transition temperature Tg. As a candidate for this slow process a sliding motion proposed by de Gennes is discussed.  相似文献   
993.
As a part of investigations to characterize trypanosome infections in Taiwan, sera collected from patients admitted to Veterans General Hospital, Taipei were tested for antitrypanosome antibodies. A Trypanosoma cruzi extract-based enzyme-linked immunosorbent assay (ELISA) was used to screen and titrate 1,297 patient sera. High antitrypanosome titers were detected in 166 (12.8%) of these sera. Retitration of random samples of the high titer (HT) sera indicated a 5.4% false positive. Thirteen donors with high antitrypanosome ELISA titers were followed up. Twelve of then remained high serum titers also showed high ELISA titers against an extract of Trypanosoma conorhini. Hemocultures conducted on freshly drawn blood specimens of the 13 subjects did not provide any evidence of trypanosome infections. Electrophoretic analyses of sera from HT and low titer (LT) patients suggested differences between serum proteins of the subjects in each of the groups. Atypical reactions were observed in immunodiffusion tests performed with HT and LT sera and trypanosome extracts, while western blot analyses revealed a complex pattern of binding by both sera. The qualitative and quantitative differences in these tests suggested interactions of T. cruzi antigens with donor antibodies against unrelated antigens and/or with autoantibodies. Subsequent analyses did not indicate any association between rheumatoid factor and the reactivities of the HT sera with the parasites. However, antinuclear antibodies were detected with an indirect fluorescent antibody test (IFAT) in 50% of the HT sera and 22% of the LT sera. No differences were found between the levels of antilaminin activity of the two groups. The IFAT employing T. cruzi epimastigotes was positive for 100% of the HT sera and 22% of the LT sera. The data indicate that the high seropositivity recognized in this study is due in part to the activities of cross-reacting antibodies and/or autoantibodies in the sample population.  相似文献   
994.
Five cellulose-binding polypeptides were detected in Cellulomonas fimi culture supernatants. Two of them are CenA and CenB, endo-beta-1,4-glucanases which have been characterized previously; the other three were previously uncharacterized polypeptides with apparent molecular masses of 120, 95, and 75 kDa. The 75-kDa cellulose-binding protein was designated endoglucanase D (CenD). The cenD gene was cloned and sequenced. It encodes a polypeptide of 747 amino acids. Mature CenD is 708 amino acids long and has a predicted molecular mass of 74,982 Da. Analysis of the predicted amino acid sequence of CenD shows that the enzyme comprises four domains which are separated by short linker polypeptides: an N-terminal catalytic domain of 405 amino acids, two repeated sequences of 95 amino acids each, and a C-terminal domain of 105 amino acids which is > 50% identical to the sequences of cellulose-binding domains in Cex, CenA, and CenB from C. fimi. Amino acid sequence comparison placed the catalytic domain of CenD in family A, subtype 1, of beta-1,4-glycanases. The repeated sequences are more than 40% identical to the sequences of three repeats in CenB and are related to the repeats of fibronectin type III. CenD hydrolyzed the beta-1,4-glucosidic bond with retention of anomeric configuration. The activities of CenD towards various cellulosic substrates were quite different from those of CenA and CenB.  相似文献   
995.
Enteric hyperoxaluria and primary hyperparathyroidism have been associated with the development of nephrolithiasis. We report a case involving a patient who had hyperparathyroidism due to a parathyroid adenoma and enteric hyperoxaluria resulting from a small bowel bypass and who had severe stone-related complications. This combination of stone-generating factors has heretofore not been reported. The pathophysiology of these entities is discussed.  相似文献   
996.
OBJECTIVE: The excess of pediatric emergencies going to hospitals has been the subject of many studies in Spain and, on some occasions, this problem has attributed to the inefficiency of pediatric primary care. Our main objective was to evaluate whether or not our community health center is an efficient filter for hospital emergencies. PATIENTS AND METHODS: We conducted a prospective one year long study of all pediatric emergency demands within our normal office hours (workdays, from 08:00 to 21:00 hours). RESULTS: The total number of emergencies amounted to 1,294, with an average of 5.78 per day. The largest inflow occurred in September and the lowest in August. Most of the emergencies were between 16:00 and 19:00 hours. Fifty percent of the patients were under 4 years of age. We made 86 different diagnoses according to the WONCA classification. Only 10 diagnoses came with a frequency superior to 3%, and 60% of the emergencies were related to one of these 10 diagnoses. Of all pediatric emergencies, 94.7% were completely resolved by us. Only 60 patients (4.6%) were sent-on to hospital emergency services. Among these patients, 40 required traumatological or surgical attention, 5 ophthalmological care, 3 otorhinolaryngological care, and only 12 exclusively needed pediatric attention. In 55.7% of the cases there was no reason to use the emergency channel. CONCLUSIONS: During our office hours, our community health center is an efficient filter for hospital pediatric emergencies.  相似文献   
997.
We describe a myelolipoma of the thoracic spine in a patient with gradual and progressive myelopathy. MR imaging showed this predominately fatty lesion to be extradural in location.  相似文献   
998.
This article describes the methodological approach of systemic psychology. In the framework of this approach a wide range of experimental data is analyzed: results of neuronal recordings in vitro and in awake normal and pathological animals learning to perform and performing both complex instrumental and simple behavioral acts. Another block of analyzed data is based on the experiments with human subjects that learn and perform the tasks of categorization of words and operator tasks, subjects, performing group game activity and answering the questionnaires of psychodiagnostic methods. As a result of this analysis, the system psychology approach is used to describe qualitatively and quantitatively the formation and realization of individual experience.  相似文献   
999.
1000.
Gangliogliomas of the optic nerve are extremely rare. The case is reported of a 38-year-old man who presented with a visual field deficit and was discovered to have an optic nerve ganglioglioma. The possible embryological origins of this neoplasm, its histological and immunohistochemical features, and its appearance on magnetic resonance imaging are examined. The prognoses of optic nerve glioma and of gangliogliomas occurring elsewhere in the nervous system are compared.  相似文献   
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