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排序方式: 共有690条查询结果,搜索用时 31 毫秒
1.
Kathryn E Arnold Jody L Schweitzer Barbara Wallace Monique Salter Ruth Neeman W Gary Hlady Bernard Beall 《Infection control and hospital epidemiology》2006,27(12):1377-1384
OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs. 相似文献
2.
Gü l Gü rsel Haluk Tü rktas Nahide G k ora Ishak
zel Tekin 《The Journal of asthma》1997,34(4):313-319
The aim of the present study was to investigate whether sputum eosinophil cationic protein (ECP) concentrations could be a useful marker in the differential diagnosis between intrinsic asthma and chronic obstructive pulmonary disease (COPD). For this purpose total blood eosinophil counts were obtained and concentrations of serum and sputum ECP from 10 nonatopic asthmatics with a mild attack and 9 COPD patients with acute exacerbation were measured by radioimmunoassay. Mean serum ECP concentration was 54.3 ± 23.0 g/L in the asthmatic group and 83.3 ± 79.2 g/L in the COPD group (p: n.s.). In the group of asthmatics mean sputum ECP level was 984.5 ± 1245.5 mg/L/g sputum and in the COPD group it was 417.5 ± 363.5 mg/L/g sputum. There was no significant difference in sputum ECP levels between patients with asthma and COPD. We conclude that neither sputum nor serum ECP levels are useful markers in differential diagnosis of asthma attack and acute exacerbation of COPD. 相似文献
3.
G. Amir S. Silberman Z. Neeman R. Udassin D. Seror E. Rosenmann 《Pediatric surgery international》1991,6(4-5):353-356
A 7 1/2-year-old girl with an inflammatory pseudotumor of the lung is presented. The nature of the lesion was not recognized pre-or intraoperatively. The lesion was rubbery, yellowish, and well-defined but not encapsulated. Histologically, a spindle-cell lesion with a storiform pattern and chronic inflammatory-cell infiltrate was seen. The immunological and ultrastructural studies supported an inflammatory origin. The lesion corresponds to the fibrous histiocytoma variant of inflammatory pseudotumor of the lung, as defined recently by Matsubara et al. [17]. This must be distinguished from rare benign neoplasms of the lung such as benign fibrous histiocytoma, leiomyoma, Schwannoma, and histiocytosis. 相似文献
4.
Alcohollike liver disease in nonalcoholics. A clinical and histologic comparison with alcohol-induced liver injury 总被引:29,自引:0,他引:29
Individuals who deny alcohol consumption may develop liver injury that histologically resembles the liver injury found in alcoholic patients. To determine whether any clinical or histologic features distinguish alcoholic and nonalcoholic subjects with "alcohollike" liver injury, the clinical records and liver biopsy specimens of 68 alcoholic and 39 nonalcoholic patients with alcohollike injury on liver biopsy were compared. The clinical and biochemical features of the two groups differed significantly. Alcoholism was associated with more severe clinical and biochemical manifestations of liver disease. However, there was considerable overlap among histologic features of the two clinically defined groups. Based on histology alone, alcoholic and nonalcoholic patients were often indistinguishable. The observations suggest that the clinical differences between the alcoholic and non-alcoholic patients cannot be attributed to qualitative or quantitative differences in liver histology. On the other hand, histologic similarities between the two groups raise the possibility that a shared condition, perhaps nutritional or hormonal, is responsible for the histologic expression of alcohollike injury in both groups. 相似文献
5.
Houkin K Fukuhara S Selladurai BM Zurin AA Ishak M Kuroda S Abe H 《Neurologia medico-chirurgica》1999,39(11):773-7; discussion 777-8
A new image transmission and teleconference system using international digital telephone services was established between Japan and Malaysia. This new system consists of an ordinary personal computer, image scanner, and terminal adapter for digital telephone lines. The quality of images transferred using this system was high enough for diagnosis and discussion except for images such as radiographs requiring huge data transfer. Transmission of one image took approximately 20 seconds. The cost performance was almost equal to the conventional mailing system. The most remarkable advantage of this new system is the high quality of transferred images, the cost and time performance, and security of the medical information. New communication systems using international digital networks including the internet may allow re-distribution of medical resources between advanced countries and developing countries in neurosurgery. 相似文献
6.
J. Jaime Caro MDCM K. Jack Ishak MSc Ingrid Caro MEd Kristen Migliaccio-Walle BS Wendy S. Klittich BS 《Value in health》2004,7(5):585-594
OBJECTIVES: Clinicians are told to use the number needed to treat (NNT) to compare the benefits of therapeutic strategies, and researchers are asked to report results this way, generally without considering differences among the studies from which these were derived. METHODS: The crude NNT currently advocated is compared to the NNT standardized for a common outcome, follow-up time, study population and comparator. An NNT model for cardiovascular disease is described as an example that addresses differences among studies of secondary prevention of cardiovascular disease. Crude NNTs are compared to those obtained from the model. RESULTS: Follow-up in the 18 trials identified varied from 1.0 to 6.2 years; rates of cardiovascular events in the untreated subgroups ranged from 4.8% to 45.9%. The crude NNTs were more variable (9.1-163.7) than those obtained from the model (9.1-75.2). The effect of standardization was substantial in some cases, with proportional changes ranging from a 91% decrease to a 223% increase. CONCLUSION: Using an NNT model to account for differences in study design allows for more meaningful comparisons. 相似文献
7.
8.
Maya Frank-Wolf Josef Tovbin Yifat Wiener Ortal Neeman Yaffa Kurzweil Ron Maymon 《The journal of maternal-fetal & neonatal medicine》2017,30(13):1637-1640
Purpose: Since more senior and attending physicians work in labor wards during morning shifts, we expect a better delivery outcome during that time period.Materials and methods: A retrospective study was conducted between 1/2005 and 12/2014. Records of 56 428 singleton deliveries from a tertiary hospital in which cord blood pH was routinely measured at birth were analyzed. Time of birth was divided into shifts: 7 AM–3?PM (morning shift), 3?PM–11?PM (afternoon shift), and 11?PM–7 AM (night shift). Additional stratification compared weekdays and weekend deliveries.Results: 19?601, 18?429, and 18?398 neonates were born during morning, afternoon, and night shifts, respectively. There was no significant difference in maternal age, neonatal weight, or mean 5-min Apgar score among the three shift periods. Furthermore, there was no correlation between shift time of delivery and newborn acidosis with respect to cord pH less than 7 (0.1% in each time periods, p?=?0.67). Despite the above, instrumental deliveries and cesarean sections were more common in the morning shift compared to the afternoon and night shift, respectively (p?=?0.001 each).Conclusions: Although shift time of delivery was found to be related to mode of delivery it was not related to either 5-min Apgar score or newborn acidosis as reflected by cord pH. 相似文献
9.
M. M. Quazi M. Ishak A. Arslan M. A. Fazal Farazila Yusof B. S. Sazzad M. Nasir Bashir M. Jamshaid 《RSC advances》2018,8(13):6858
Laser composite surfacing (LCS) is a photon driven manufacturing technology that can be utilized for depositing hybrid metal matrix composite coatings (HMMC) on softer Ti/Al/Mg alloys to enhance their tribo-mechanical properties. LCS offers the advantages of higher directionality, localized microstructural refinement and higher metallurgical bonding between coating and substrate. The current research presents the tribo-mechanical evaluation and characterization of solid lubricant based Ni–WC coatings deposited by LCS on Al–Si piston alloy by varying the concentration of graphite between 5-to-15-weight percentage. The tribological behavior of LCS samples was investigated using a ball-on-plate tribometer. Results indicate that the surface hardness, wear rate and friction coefficient of the Al–Si hypereutectic piston alloy were improved after LCS of graphite based HMMC coatings. The maximum surface hardness of 781Hv was acquired for the Ni–WC coating containing 5 wt% graphite. The friction coefficient of Al–Si under dry sliding conditions was reduced from 0.47 to 0.21. The reduction in the friction coefficient was attributed to the formation of a shearable transfer layer, which prevented delamination and reduced adhesion, abrasion and fatigue cracking.The addition of graphite as solid lubricant has significantly reduced the friction coefficient and wear of a Ni–WC composite coating. 相似文献
10.
Long-term mortality and morbidity of transfusion-associated non-A, non-B, and type C hepatitis: A National Heart, Lung, and Blood Institute collaborative study 总被引:10,自引:0,他引:10
Seeff LB Hollinger FB Alter HJ Wright EC Cain CM Buskell ZJ Ishak KG Iber FL Toro D Samanta A Koretz RL Perrillo RP Goodman ZD Knodell RG Gitnick G Morgan TR Schiff ER Lasky S Stevens C Vlahcevic RZ Weinshel E Tanwandee T Lin HJ Barbosa L 《Hepatology (Baltimore, Md.)》2001,33(2):455-463
Persons with non-A, non-B hepatitis (cases) identified in 5 transfusion studies in the early 1970s have been followed ever since and compared for outcome with matched, transfused, non-hepatitis controls from the same studies. Previously, we reported no difference in all-cause mortality but slightly increased liver-related mortality between these cohorts after 18 years follow-up. We now present mortality and morbidity data after approximately 25 years of follow-up, restricted to the 3 studies with archived original sera. All-cause mortality was 67% among 222 hepatitis C-related cases and 65% among 377 controls (P = NS). Liver-related mortality was 4.1% and 1.3%, respectively (P =.05). Of 129 living persons with previously diagnosed transfusion-associated hepatitis (TAH), 90 (70%) had proven TAH-C, and 39 (30%), non-A-G hepatitis. Follow-up of the 90 TAH-C cases revealed viremia with chronic hepatitis in 38%, viremia without chronic hepatitis in 39%, anti-HCV without viremia in 17%, and no residual HCV markers in 7%. Thirty-five percent of 20 TAH-C patients biopsied for biochemically defined chronic hepatitis displayed cirrhosis, representing 17% of all those originally HCV-infected. Clinically evident liver disease was observed in 86% with cirrhosis but in only 23% with chronic hepatitis alone. Thirty percent of non-A, non-B hepatitis cases were unrelated to hepatitis viruses A,B,C, and G, suggesting another unidentified agent. In conclusion, all-cause mortality approximately 25 years after acute TAH-C is high but is no different between cases and controls. Liver-related mortality attributable to chronic hepatitis C, though low (<3%), is significantly higher among the cases. Among living patients originally HCV-infected, 23% have spontaneously lost HCV RNA. 相似文献