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991.
Toward high-precision service retrieval 总被引:1,自引:0,他引:1
Online repositories are increasingly called on to provide access to services that describe or provide useful behaviors. Existing techniques for finding services offer low retrieval precision, returning many irrelevant matches. We introduce a novel service retrieval approach that captures service semantics using process models, and applies a pattern-matching algorithm to find the services with the behavior the user wants. Evaluations suggest that process-based queries offer substantially greater retrieval precision than existing approaches and scale well with the number of services being accessed. 相似文献
992.
JF Eary KA Krohn OW Press L Durack ID Bernstein 《Canadian Metallurgical Quarterly》1997,24(7):635-638
We have been developing a new type of centrifugal pump for long-term use. The magnetically suspended centrifugal pump (MSCP) contains no shaft and seal so that long life expectancy is predicted. Paracorporeal left ventricular (LV) assist circulation between the left atrium and the descending aorta was instituted using sheep. The flow rates ranged from 2.5-5.5 L/min. The sheep that lived the longest (46 days) died of an embolism as a result of the thrombus in the pump. No thrombus formation was observed in other pumps. Plasma free hemoglobin levels ranged from 9 to 18 mg/dl, which led to the conclusion that the hemolysis level remained within an acceptable range. Two driving modes were compared. The slope of the pressure-flow relationship plot under a constant motor current mode was steeper than that under a constant rotational speed mode, and thus, the flow fluctuation decreased. In conclusion, the MSCP is durable for more than a month at the current stage of development and is a promising device for long-term ventricular assist. 相似文献
993.
OBJECTIVE: To review the morbidity and mortality among 68 premature infants treated with enterostomy for necrotizing enterocolitis. DESIGN: Data were collected retrospectively from hospital medical records to include the period between January 1, 1987, and September 30, 1997. SETTING: Tertiary care children's hospital. PATIENTS: A group of 68 infants aged 2 to 35 days (mean age, 12.5 days), weighing 1500 g or less, with necrotizing enterocolitis necessitating surgical enterostomy for treatment. INTERVENTIONS: Creation of any enterostomy during exploratory laparotomy for necrotizing enterocolitis and subsequent closure. MAIN OUTCOME MEASURES: Morbidity and mortality associated with infant enterostomy and its closure. RESULTS: Thirty-nine infants underwent ileostomy with mucous fistula, 16 underwent ileostomy with a Hartmann pouch, 7 had jejunostomy with mucous fistula, 2 had colostomy with mucous fistula, and 4 had colostomy with a Hartmann pouch. Eighteen (26%) of the 68 infants died in the postoperative period of sepsis (n = 10), continuing necrotizing enterocolitis (n = 5), or respiratory distress (n = 3). Of the remaining 50 infants, complications developed in 34 (68%). These complications included strictures requiring further resection at the time of enterostomy closure in 20 infants; stricture of the enterostomy requiring surgical revision in 6; incisional hernia in 3; parastomal hernia in 4; enterostomal prolapse or intussusception in 6 and 1, respectively; wound dehiscence in 4; wound infection in 8; small-bowel obstruction requiring laparotomy in 2; and anastomotic complications in 2. Only 16 enterostomies were closed uneventfully, with 3 of these infants subsequently dying of sudden infant death syndrome between 6 and 8 months after the operation. Of the surviving infants, 3 (6%) continue to require home hyperalimentation. CONCLUSIONS: Although enterostomy in infants with low birth weight with necrotizing enterocolitis may be lifesaving, it is also a major cause of morbidity. These data suggest the feasibility of a prospective study comparing resection and primary anastomosis with resection and enterostomy. 相似文献
994.
Epididymocutaneous fistula is a rare entity. A recent case in a patient with the acquired immunodeficiency syndrome and Marfan's syndrome led to this review. The patient's immunocompromised status as well as his past medical history necessitated special considerations in the diagnosis and management of his epididymocutaneous fistula. 相似文献
995.
M Nielen FC Jansen LA van Wuijckhuise AA Dijkhuizen 《Canadian Metallurgical Quarterly》1996,121(20):576-581
The performance of the Dutch cattle I&R system was analysed, with emphasis on the potential use of the system for the control of an outbreak of foot and mouth disease (FMD). The analysis showed that not all mutations were centrally registered within the three working days that are allowed to pass between the actual change and the obligatory report. In particular, young calves and cattle heading for slaughter were reported too late. During an outbreak of FMD, the best strategy to trace animals off a farm seems to be first to identify all animals on the farm, using a preprocessed list of the animals that should be present on the farm according to the I&R system. Then all the animals that have left the farm during the last month can be traced in the central I&R computer or by asking the person to whom the farmer sold the cattle (the next owner). In the present study, 54% of the animals were localized within one day, and 94% within one week. Finally, some suggestions for improvement for the system are given. 相似文献
996.
The current restructuring of the U.S. health care delivery system is driven primarily by economic forces. Although primary care providers may understand the roles of technology and advocacy in fostering fundamental change, they may not be familiar with the issues related to financing of health care and, thus, may not fully appreciate the extent to which economic factors influence the character of their professional lives and the services they provide. Analysis of the loss of the home birth option in the 1950s provides a method for understanding and influencing the factors driving health care restructuring today. In examining short-stay delivery in the 1990s, this article also addresses ways in which managed health care systems may improve or restrict women's access to a variety of primary care services. 相似文献
997.
The signal recognition particle 54-kDa subunit (SRP54) binds to the signal sequences of nascent presecretory and transmembrane proteins. Previous studies have shown that signal sequences bind to the C-terminal methionine-rich domain of the protein (M-domain), but have raised the possibility that either the N-terminal domain (N-domain) or the central guanosine triphosphatase module (GTPase-domain) also contribute to signal-sequence-binding activity. We have generated a series of N-domain and GTPase-domain mutants to investigate this issue further. Mutations in a conserved N-domain motif (ALLEADV) produced significant defects in signal sequence binding that correlate with the severity of the mutation. The magnitude of the defect was independent of the preprotein substrate, which suggested that the mutations do not alter the specificity of signal sequence recognition. The N-domain mutants also showed defects in promoting the translocation of presecretory proteins across the membrane of microsomal vesicles, but these defects appeared to be a direct consequence of the reduction in signal-sequence-binding activity and not separate effects of the mutations. By contrast, mutations in the guanosine triphosphatase consensus sequence had no effect on signal sequence binding, but instead severely impaired protein translocation activity. These results indicate that a principal function of the SRP54 N-domain is to promote efficient signal sequence binding. These data also suggest that the SRP54 GTPase regulates the cycle of signal sequence binding and release, perhaps by modulating the relative orientation of the N- and M-domains. 相似文献
998.
SJ Kern RS Smith WR Fry SD Helmer JA Reed FC Chang 《Canadian Metallurgical Quarterly》1997,63(8):669-674
The role of lysozyme in the immune immobilisation of Treponema pallidum is not yet fully understood. The T. pallidum immobilisation assay was used to demonstrate that the immobilisation and lysis of T. pallidum in vitro by antibodies (serum, IgG fraction or IgM fraction) and complement proceed in a lysozyme-independent mode. In the presence of lysozyme the rate of immobilisation increased. In contrast with its effect on Escherichia coli, the effect of lysozyme on T. pallidum was governed exclusively by its enzymic activity rather than by the cationic protein nature of the molecule. Lysozyme, released from stimulated phagocytes, induced formation of lysozyme antibodies in 59.6% of syphilis patients as determined by lysozyme antibody ELISA. The highest frequency was found in patients with untreated secondary syphilis, whereas untreated primary syphilis was only rarely accompanied by the presence of lysozyme antibodies. Cross-reactivities between lysozyme and treponemal antigens were excluded by immunoblotting. The autoantibodies did not influence the lysozyme activity. It was concluded that the formation of lysozyme antibodies is only an epiphenomenon in the host defence against treponemal infection. 相似文献
999.
SM Sheen-Chen CW Chou MC Chen FC Chen YS Chen JJ Chen 《Canadian Metallurgical Quarterly》1997,44(17):1488-1494
BACKGROUND/AIMS: The prognosis of patients with gastric adenocarcinoma varies with the location of the tumor. Adenocarcinoma in the middle third of the stomach has been claimed to have a better outcome than those in other locations. However, there is still very limited information specifically regarding the prognostic factors which influence the survival time of patients with adenocarcinoma in the middle third of the stomach. This retrospective study was designed with the aim to evaluate and uncover the possible significant clinicopathological parameters for adenocarcinoma in the middle third of the stomach. METHODOLOGY: Between 1986 and 1992, 363 patients underwent gastric resection for primary gastric adenocarcinoma at this hospital. Fifty-two (14.3%) of these patients were included in this study and they all met the following criteria: 1) tumor primarily located in the middle third of the stomach without distant metastases or peritoneal seeding, 2) undergoing curative resection and 3) undergoing R2 nodal dissection, at least. The clinicopathological findings were obtained by detailed review of the medical records and the histologic slides. All surviving patients were also contacted and their current conditions were recorded. RESULTS: The overall 5-year survival rate (Kaplan-Meier method) was 42.5%. In univariate survival analysis by Kaplan-Meier method and long-rank test, serosal invasion (p < 0.01), lymph node metastasis (p < 0.01) and lymphatic involvement (p < 0.01) had an individual prognostic significance. When a multivariate analysis using Cox proportional hazards regression was performed, serosal invasion (P < 0.01) and lymphatic involvement (p < 0.05) appeared as the only two independent prognostic factors regarding long-term survival. When these 52 patients were categorized into patients with early gastric cancer (n = 10) and patients with advanced gastric cancer (n = 42), there was a significant difference (p < 0.01) between the survival rates (90.0% vs. 29.1%). When these tumors were further categorized into early gastric cancer (n = 10), early simulating advanced gastric cancer (n = 14) and Borrmann type advanced gastric cancer (n = 28), there were significant differences (P < 0.01 and P < 0.01, respectively) in 5-year overall survival rates between early gastric cancer (90.0%) and Borrmann type advanced gastric cancer (18.9%), also between early simulating advanced gastric cancer (52.5%) and Borrmann type advanced gastric cancer (18.9%). UICC stage also had significant influence (P < 0.01) on the survival rates. CONCLUSIONS: Serosal invasion and lymphatic involvement are the significant, independent prognostic factors in predicting the survival rate of patients with adenocarcinoma in the middle third of the stomach. Since more advanced stage tumors usually carry a poorer prognosis, early detection is of extreme importance for improving the survival rate. 相似文献