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排序方式: 共有735条查询结果,搜索用时 46 毫秒
1.
Between June and September, 1986, an outbreak of measles occurred in Pilkhi Primary Health Centre area (population 56,000) in Tehri Garhwal district, Uttar Pradesh, India. Overall, 1092 cases were identified and 62 died; case-fatality ratio was 5.7%. Illness was restricted primarily to children below 15 years of age; 38% cases were in children under 5 and 58% between 5-14 years of age. To better characterize the outbreak, a survey was conducted in 13 affected villages. The age of the cases ranged from 5 months to 19 years (median = 7.0 years). The age-specific attack rates were 22.4%, 54.5%, 46.2% and 35.3% for children under 1, 1-4, 5-9, 10-14 years of age respectively. In as many as four villages, the attack rate in children below ten was 80% or more. Secondary attack rate among family members was 70%. Overall, 82% of children with measles developed complications which consisted mainly of pneumonia, diarrhoea and dysentery. The age-specific case-fatality ratios in infants and children 1-4 years of age were 23.1% and 11.5% respectively; thereafter the rates tended to decline with increasing age and was higher in females than in males (less than 0.05). Pneumonia which was a complication in 39% of measles cases contributed to 56% of deaths. Traditional beliefs and customs in the area were strong and did not encourage treatment of measles cases. Although a measles vaccination programme has been launched in India since 1985, only 30 districts could be covered during the first year and another 90 during 1986.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
2.
Background: Whether or not laparoscopic cholecystectomy may be performed safely as an outpatient procedure is controversial. In 1993,
a protocol for outpatient laparoscopic cholecystectomy was instituted to determine the benefits and safety of discharging
patients within several hours of surgery.
Methods: The initial 60 outpatient laparoscopic cholecystectomies performed by one surgeon in a hospital-based outpatient teaching
facility between February 1993 to June 1996 were prospectively studied.
Results: Fifty-eight (97%) patients were discharged successfully after an average stay in the recovery room of 3 h. There were no
deaths. Two patients required overnight observation and three patients required readmission. Two patients (3%) had cystic
duct leak. The average hospital stay for all patients undergoing laparoscopic cholecystectomy at the institution (inpatient
and outpatient) decreased from 3.2 to 1.5 days and the average hospital cost decreased from $7,800 to $4,600 during this period.
Conclusion: Laparoscopic cholecystectomy in an outpatient setting is safe and cost-effective in healthy patients.
Received: 3 April 1997/Accepted: 10 June 1997 相似文献
3.
The authors presented a new posterior beam-stop (PBS) technique for measuring the ratio of scattered to total-detected photon flux (scatter fraction) in a radiographic examination while preserving the diagnostic quality of the image. The scatter measurement was made using a standard imaging geometry with both beam stops and an additional x-ray detector placed behind the standard imaging detector. This PBS geometry differs from the standard beam-stop (SBS) technique for scatter measurement. With SBS, a beam-stop shadow appears on the image. To evaluate the PBS technique, scatter fraction measurements were performed on an anatomic phantom using both the PBS and SBS techniques. When compared with the standard technique, PBS provided accurate estimation of scatter fractions. Since the measurement can be performed without degrading a standard clinical radiographic examination, the PBS technique allows simultaneous acquisition of scatter measurements from human patients in combination with a standard radiographic examination. 相似文献
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Adrian Ooi Narain Moorjani Giedrius Baliulis Barry R. Keeton Anthony P. Salmon James L. Monro Marcus P. Haw 《European journal of cardio-thoracic surgery》2006,30(6):917-922
Objective: To assess the impact of early corrective surgery on the short and medium term outcome in tetralogy of Fallot (TOF). Materials and methods: All patients under 12 months of age undergoing correction of isolated TOF between February 1997 and July 2003 were reviewed retrospectively. Outcome data for mortality, post-operative care management, major morbidity and clinical follow-up were analysed. Results: Fifty-two operations were performed. The mean age at surgery was 5 months (range 1–12) of whom 16 (30.8%) were less than 3 months old, including 2 neonates, 22 (42.3%) were 3–6 months old and 14 (26.9%) were 7–12 months old. There was 1 (1.9%) early death caused by a cerebro-vascular accident and 1 (1.9%) late death secondary to acute infective endocarditis. There were no differences in post-operative morbidities attributable to age. Patients under 3 months old required greater duration of post-operative ventilation, ITU stay and in-hospital stay. At a mean follow-up of 4.0 years (range 1.5–8.0), 33 (63.5%) patients had well-tolerated pulmonary regurgitation (PR) and 3 (5.8%) patients required re-operation for right ventricular outflow tract obstruction (RVOTO). All patients had right bundle-branch-block but with QRS < 150 ms. Conclusion: Early definitive repair of TOF can be performed safely on patients under 6 months old. Age at surgery does not appear to affect the medium term haemodynamic outcome. However, early surgery does escalate the need for ICU care. This data suggests repair in asymptomatic patients be delayed until 3–6 months of age. 相似文献
6.
Characterization of a novel leucine-rich repeat protein antigen from group B streptococci that elicits protective immunity 总被引:4,自引:0,他引:4
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Seepersaud R Hanniffy SB Mayne P Sizer P Le Page R Wells JM 《Infection and immunity》2005,73(3):1671-1683
Group B streptococci (GBS) usually behave as commensal organisms that asymptomatically colonize the gastrointestinal and urogenital tracts of adults. However, GBS are also pathogens and the leading bacterial cause of life-threatening invasive disease in neonates. While the events leading to transmission and disease in neonates remain unclear, GBS carriage and level of colonization in the mother have been shown to be significant risk factors associated with invasive infection. Surface antigens represent ideal vaccine targets for eliciting antibodies that can act as opsonins and/or inhibit colonization and invasion. Using a genetic screen for exported proteins in GBS, we identified a gene, designated lrrG, that encodes a novel LPXTG anchored surface antigen containing leucine-rich repeat (LRR) motifs found in bacterial invasins and other members of the LRR protein family. Southern blotting showed that lrrG was present in all GBS strains tested, representing the nine serotypes, and revealed the presence of an lrrG homologue in Streptococcus pyogenes. Recombinant LrrG protein was shown in vitro to adhere to epithelial cells in a dose-dependent manner, suggesting that it may function as an adhesion factor in GBS. More importantly, immunization with recombinant LrrG elicited a strong immunoglobulin G response in CBA/ca mice and protected against lethal challenge with virulent GBS. The data presented in this report suggest that this conserved protein is a highly promising candidate antigen for use in a GBS vaccine. 相似文献
7.
Ravin AG Olbrich KC Levin LS Usala AL Klitzman B 《Journal of biomedical materials research》2001,58(3):313-318
Fibrous capsule formation around implants can inhibit solute exchange between implantable devices and the circulation. Parylene-n coated polycarbonate disks surrounded with growth factor reduced Matrigel (MG) or several gelatin-based matrices were implanted intramuscularly into rats for 21 or 50 days. MG supplemented with vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) increased capsule microvascular density at 21 days (p < 0.05) when compared to bare parylene-coated polycarbonate disks (control). The increased microvascular density around VEGF- and bFGF-treated implants regressed by 50 days and was no longer significantly different from controls. The microvascular density induced by the gelatin-based matrices was not significantly different from controls at 21 days, but was increased at 50 days (p < 0.05), suggesting a slower, long-term effect. Disks treated with MG and gelatin-based matrices had thinner capsules at 21 days (p < 0.05). By 50 days, the capsule thicknesses around these implants were no longer statistically thinner than controls. The capsule thickness around implants treated with VEGF, bFGF, and essential gelatin-based matrix was thinner than controls at 50 days (p < 0.05). These results indicate that it is possible to increase functional microvascular density within fibrous capsules using angiogenic growth factors and gelatin-based matrices. However, this effect may be short-lived, requiring chronic administration of growth factors. 相似文献
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10.
Rajiv Bharat Kharwar M.D. Rishi Sethi M.D. D.M. F.A.C.C. Varun Shankar Narain M.D. D.M. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(10):E322-E325
Endomyocardial fibrosis is a form of restrictive cardiomyopathy mainly affecting poor children and young adults in geographically restricted areas of Latin America, Africa, and Southeast Asia. The pathophysiological hallmark of the disease is focal or diffuse endocardial thickening involving mainly the inflow, the apices, and the subvalvular region leading to valvular regurgitation, diastolic dysfunction and obliteration of the ventricular apex. Advanced right‐sided disease has slow flow of blood through chambers with propensity of thrombus formation especially in the right atria. Although two‐dimensional transthoracic echocardiography remains the cornerstone for the diagnosis of this disease, the case presented here shows how three‐dimensional transthoracic echocardiography can add substantial information regarding the region of involvement of the right ventricle as well as the various characteristics of the right atrial thrombus. 相似文献