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21.

Background  

The Data Envelopment Analysis (DEA) method has been fruitfully used in many countries in Asia, Europe and North America to shed light on the efficiency of health facilities and programmes. There is, however, a dearth of such studies in countries in sub-Saharan Africa. Since hospitals and health centres are important instruments in the efforts to scale up pro-poor cost-effective interventions aimed at achieving the United Nations Millennium Development Goals, decision-makers need to ensure that these health facilities provide efficient services. The objective of this study was to measure the technical efficiency (TE) and scale efficiency (SE) of a sample of public peripheral health units (PHUs) in Sierra Leone.  相似文献   
22.
We estimate the incidence and describe patterns of work-related injuries during 1998 to youth in retail trades and services industries. Data from the National Electronic Injury Surveillance System and the Current Population Survey were analyzed. The highest number of work-related injuries to youth younger than 18 years occurred in eating and drinking establishments and food stores. Injuries occurring in these industries accounted for 44% of all young worker injuries. Injury rates were similar during summer and school months. Youth continue to experience high numbers and rates of injuries in retail trades and services. Improvements in safety training and injury prevention in these industries, particularly eating and drinking establishments, food stores, and health services, need to be addressed for youth.  相似文献   
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Objective  To investigate the efficacy and safety of suction–curettage with a combination of two different cannulae for treatment of axillary osmidrosis and hyperhidrosis.
Design  Retrospective analysis of patients who underwent surgery from September 2004 to September 2006.
Setting  Outpatient clinic for hyperhidrosis at a university-affiliated hospital.
Subjects  Sixty-five patients who were treated for axillary malodor and hyperhidrosis.
Interventions  Patients were sequentially treated with Fatemi and Cassio cannulae.
Main outcome measures  Demographic data, severity data (assessment of malodor), degree of satisfaction, sweating, hair growth, scarring, recurrence and complications.
Results  Sixty of the 65 patients (96.9%) had excellent to fair results, and only 2 patients (3.1%) had poor results. Complications occurred in 4 patients (6.2%). Recurrence occurred in 3 patients (4.6%).
Conclusions  This simplified and inexpensive method resulted in a high success rate with low complications and high satisfaction with minimal scarring and rapid recovery.  相似文献   
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AIM To study the clonality of the esophageal carcinosarcoma by using molecular approaches.METHODS Two esophageal carcinosarcomas were included in the study. Tumor area from dysplasticlesion, squamout cell carcinoma, basaloid cell carcinoma and spindle cell elements were microdissectedseparately. Each element was analyzed with 14 microsatellite markers and direct sequenced for p53 gene andras gene mutation.RESULTS Both tumors displayed a typical histologic feature of carcinosarcoma. Both cases showed thedivergent differentiation by immunohistochemistry study. In case 1 the identical LOH at p53 and hMLH1 lociwas detected. The heterogenous LOH was detected only in carcinosarcoma at RB1 and BRCA1 loci, whilethe LOH at ACTC locus was seen only in sarcoma. The same mutation of the splice site of exon 6-intron 6displayed in the two tumor elements. In case 2, a coordinate LOH at RB locus was demonstrated in threetypes of tumor elements: sqamous carcinoma, basaloid carcinoma and spindle cell element. A heterogenousLOH was seen only in spindle cells at TAP1 locus. No mutation in exon 5-8 of p53 gene has been found incase 2. No mutation of K-ras gene was found.CONCLUSION Although the different differentiation, the two elements of esophageal carcinosarcoma mayhave a single clonality. The p53 gene mutation occurred before the two differentiation directions switched.The distinct molecular genotype can be determined through molecular biological analysis. The microsatelliteprofiling can serve as an approach to find out which genetic alteration occurs before or after thedifferentiation is determines.  相似文献   
29.
The origin of low-grade mucosa-associated lymphoid tissue (MALT)-type B- cell lymphoma is still unclear. Using a novel two-step procedure, we have sequenced the Ig VH genes expressed by cells from four patients with gastric low-grade MALT-type lymphoma. The nucleotide sequences of the complementarity determining region 3 (CDR3) of the genomic DNA were first amplified using consensus oligonucleotide primers, then sequenced. Based on the CDR3 sequence amplified from each MALT lymphoma, individual tumor-specific primers were synthesized and used directly in the polymerase chain reaction (PCR) to analyze the sequences of their Ig heavy-chain variable region. When compared with the germ-line sequence, many nucleotide substitutions, mainly in the CDRs, were found in the variable gene sequences of the four MALT lymphomas. The mutations showed a high replacement-to-silent ratio and were distributed in a way which suggested that the tumor cells had been positively selected through their antigen receptor. Our findings indicate that the MALT-type lymphoma B cells are hypermutated postgerminal center lymphocytes that have undergone antigen selection.  相似文献   
30.
Hemoglobinopathies have a protective role in malaria that appears to be related to alterations in red blood cell (RBC) properties. Thalassemic RBCs infected with Plasmodium falciparum showed greatly reduced cytoadherence and rosetting properties as well as impaired growth and multiplication. A significant decrease in the levels of falciparum antigens associated with the membrane of infected beta-thalassemic RBCs was observed at trophozoite/schizont stage, but not young ring stage. This reduction was shown when a cytoadherence inhibitory monoclonal antibody, but not a noninhibitory pooled immune serum, was used. These observations suggest that protection against malaria in thalassemia is caused by both reduced parasitemias and altered adherence properties of the infected thalassemic RBCs that promote enhanced clearance of the parasite from the circulation.  相似文献   
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