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42.
Bacterial indicators of pollution of the Douala lagoon, Cameroon: Public health implications 总被引:1,自引:1,他引:0
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Jane-Francis TK Akoachere Pius M Oben Beryl S Mbivnjo Lucy M Ndip Gerald Nkwelang Roland N Ndip 《African health sciences》2008,8(2):85-89
Background
Indiscriminate disposal of untreated wastes which are often heavily laden with sewage microorganisms some of which are pathogenic to humans into aquatic environments near cities could serve as potential dangers to human health.Objective
A prospective study was undertaken to investigate the scope of potential bacterial pathogens and to assess the extent of pollution of the Douala lagoon.Methods
A total of eighty water samples were collected fortnightly from the lagoon at five stations from March to October 2005 and analysed for heterotrophic bacterial densities, coliform counts, faecal coliform and faecal streptococcal counts. Bacteria were isolated and identified using standard microbiology and biochemical techniques.Results
High heterotrophic bacterial counts (33 × 105 − 161 × 105 CFU/ mL), total coliform counts (1.8 × 102 − 2.4 × 102 CFU/100 mL), faecal coliform counts (2.2 × 102 − 2.4 × 102 CFU/ 100 mL) and faecal streptococcal counts (2.1 × 102 − 2.3 x 102 CFU/100mL were observed in all sampling stations. Eleven species of bacteria: Bacteroides fragilis, Proteus vulgaris, Klebsiella pneumoniae, E. coli, Enterococcus faecalis, Enterobacter aerogenes, Citrobacter freundii, Aeromonas hydrophila, Pseudomonas aeruginosa, Bacillus mycoides and Serratia marcesens, were frequently isolated.Conclusion
The presence of potential bacterial agents such as Bacteroides fragilis, Pseudomonas aeruginosa, Aeromonas hydrophila, Klebsiella pneumoniae and E. coli in the lagoon may pose a serious threat to the health and well being of users of the Lagoon and calls for urgent intervention. 相似文献43.
Sujoy Pal Joseph George Anand Narayan Singh Sandeep Mathur Nihar Ranjan Dash Pramod Garg Peush Sahni TK Chattopadhyay 《Journal of gastrointestinal cancer》2018,49(3):252-259
Background
The ‘SMA-first’ (P-SMA) pancreatoduodenectomy (PD) allows dissection directly on the right lateral aspect of superior mesenteric artery (SMA) which may decrease circumferential resection margin (CRM) positivity. This comparative study between standard PD (sPD) and P-SMA approach was planned focusing on CRM involvement.Methods
This was a prospective study comparing consecutive patients with resectable periampullary cancers (PACA) undergoing PD using the standard or P-SMA approach. The perioperative outcomes and the CRM positivity rates (specimens analysed according to the standardized Leeds pathology protocol (LEEPP)) were compared.Results
Overall, 39 patients (28 men; mean age 54 years; sPD 21, P-SMA 18) were included. Both groups were comparable with regard to demographic/tumour characteristics and perioperative outcomes. The P-SMA technique was significantly faster (321.1 ± 54.0 vs. 357.6 ± 55.8 min; p = 0.05). Though the mean tumour size (2.2 vs. 2.1 cm; p = 0.84) and T stage (T2 and T3) distribution were similar in both groups, lymph node yield was significantly higher in the P-SMA group (10.7 vs. 5.95; p = 0.001; mean 8 (2–21)). Though CRM positivity (margin <1 mm) occurred in 8 (21.1%), we did not find the P-SMA PD to yield significantly lower CRM positivity rates compared to the sPD (3/17 (17.6%) vs. 5/21(23.8%); p = 0.71). At a median follow-up of 28 months, fewer patients in the P-SMA PD group developed recurrence (2/15 vs. 5/19; p = 0.3) or died (3/15 vs. 7/19; p = 0.19), though this difference was not significant.Conclusions
In patients with resectable PACA, P-SMA PD was significantly faster and yielded higher lymph node counts in the specimen but did not lower the rate of CRM positivity as determined by the LEEPP.44.
Background: A case control study was carried out to study the emerging risk factors for coronary artery disease in Indians. 相似文献
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46.
Schuler PJ Trellakis S Greve J Bas M Bergmann C Bölke E Lehnerdt G Mattheis S Albers AE Brandau S Lang S Whiteside TL Bier H Hoffmann TK 《European journal of medical research》2010,15(8):337-344
Background
Systemic treatment of head and neck squamous cell carcinoma (HNSCC) includes a variety of antineoplastic drugs. However, drug-resistance interferes with the effectiveness of chemotherapy. Preclinical testing models are needed in order to develop approaches to overcome chemoresistance.Methods
Ten human cell lines were obtained from HNSCC, including one with experimentally-induced cisplatin resistance. Inhibition of cell growth by seven chemotherapeutic agents (cisplatin, carboplatin, 5- fluorouracil, methotrexate, bleomycin, vincristin, and paclitaxel) was measured using metabolic MTT-uptake assay and correlated to clinically-achievable plasma concentrations.Results
All drugs inhibited cell growth in a concentration-dependent manner with an IC50 comparable to that achievable in vivo. However, response curves for methotrexate were unsatisfactory and for paclitaxel, the solubilizer cremophor EL was toxic. Cross-resistance was observed between cisplatin and carboplatin.Conclusion
Chemosensitivity of HNSCC cell lines can be determined using the MTT-uptake assay. For DNA-interfering cytostatics and vinca alkaloids this is a simple and reproducible procedure. Determined in vitro chemosensitivity serves as a baseline for further experimental approaches aiming to modulate chemoresistance in HNSCC with potential clinical significance. 相似文献47.
LW Law TK Lau TY Fung TY Leung CC Wang KW Choy 《BJOG : an international journal of obstetrics and gynaecology》2009,116(2):339-343
Objective We investigated the application of high-resolution microarray-based comparative genomic hybridisation (array CGH) on a fetus showing increased nuchal translucency (NT).
Design Case study.
Setting Tertiary referral obstetrics unit.
Sample Pregnant woman attended the antenatal clinic.
Methods Conventional karyotyping and genetic test was carried out for the alpha-globin gene. High-resolution array CGH using the high-density 244K Agilent microarray was performed on fetal blood sample by cordocentesis to investigate the possibility of any genomic imbalance.
Main outcome measures Detection of chromosomal abnormality.
Results Karyotyping analysis showed 46,XY. Molecular genetic diagnosis confirms the fetus has Hb-H constant spring disease but cannot explain the increased NT to 3.2 mm. Array CGH analysis discovered a 1.32-Mb microdeletion on chromosome 16p13.11. Deletion at 16p13.11 has been implicated to predispose to autism and/or mental retardation. Baby was delivered at 40 weeks of gestation, and follow up was carried out at 3 months of age without sign of mental retardation/developmental delay.
Conclusions This case study demonstrated that array CGH can accurately calibrate the size and identify de novo interstitial chromosome imbalances. However, the presence of chromosome copy variants with unknown clinical significance currently limits its wider scale application in prenatal diagnosis and needs further investigations. 相似文献
Design Case study.
Setting Tertiary referral obstetrics unit.
Sample Pregnant woman attended the antenatal clinic.
Methods Conventional karyotyping and genetic test was carried out for the alpha-globin gene. High-resolution array CGH using the high-density 244K Agilent microarray was performed on fetal blood sample by cordocentesis to investigate the possibility of any genomic imbalance.
Main outcome measures Detection of chromosomal abnormality.
Results Karyotyping analysis showed 46,XY. Molecular genetic diagnosis confirms the fetus has Hb-H constant spring disease but cannot explain the increased NT to 3.2 mm. Array CGH analysis discovered a 1.32-Mb microdeletion on chromosome 16p13.11. Deletion at 16p13.11 has been implicated to predispose to autism and/or mental retardation. Baby was delivered at 40 weeks of gestation, and follow up was carried out at 3 months of age without sign of mental retardation/developmental delay.
Conclusions This case study demonstrated that array CGH can accurately calibrate the size and identify de novo interstitial chromosome imbalances. However, the presence of chromosome copy variants with unknown clinical significance currently limits its wider scale application in prenatal diagnosis and needs further investigations. 相似文献
48.
Mandeep Singh MRCSEd Jovina LS See FRCSEd Maria C Aquino MD Lennard SY Thean FRCSEd Paul TK Chew FRCSEd 《Clinical & experimental ophthalmology》2009,37(4):345-351
Background: The aim of this work was to image trabeculectomy blebs using spectral domain optical coherence tomography (SDOCT).
Methods: In this prospective cross-sectional study, patients who had undergone trabeculectomy with at least 3 months of follow up were included. Blebs were imaged using an adapted SDOCT system (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) and time domain anterior segment optical coherence tomography (ASOCT) (Visante OCT, Carl Zeiss Meditec Inc.). An observer masked to clinical data assessed the utility of SDOCT and ASOCT in visualizing structures in successful and failed blebs.
Results: Fifty-one eyes were imaged, of which 43 (84.3%) were successful. SDOCT showed wall thickening (93.0% vs. 67.4%, P = 0.006) and discrete hyporeflective spaces in the wall (88.4% vs. 14.0%, P < 0.0001) in a greater proportion of successful blebs than ASOCT. SDOCT showed the bleb cavity (23.3% vs. 48.8%, P = 0.02), scleral flap (34.9% vs. 90.7%, P < 0.0001), subflap space (20.9% vs . 72.1%, P < 0.0001) and ostium (9.3% vs. 88.4%, P < 0.0001) in fewer successful blebs than ASOCT. The internal ostium was not visualized in any failed bleb using SDOCT, whereas ASOCT showed the ostium in 87.5% of failed blebs ( P = 0.001). SDOCT showed cystic spaces in the bleb wall in a greater proportion of successful blebs than failed blebs (88.4% vs. 37.5%, P = 0.005).
Conclusions: SDOCT imaging was able to show fine superficial features in the bleb wall. However, SDOCT had limited clinical utility in that it did not provide useful information about deep features such as flap position, bleb cavity formation or patency of the subflap space and internal ostium. 相似文献
Methods: In this prospective cross-sectional study, patients who had undergone trabeculectomy with at least 3 months of follow up were included. Blebs were imaged using an adapted SDOCT system (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) and time domain anterior segment optical coherence tomography (ASOCT) (Visante OCT, Carl Zeiss Meditec Inc.). An observer masked to clinical data assessed the utility of SDOCT and ASOCT in visualizing structures in successful and failed blebs.
Results: Fifty-one eyes were imaged, of which 43 (84.3%) were successful. SDOCT showed wall thickening (93.0% vs. 67.4%, P = 0.006) and discrete hyporeflective spaces in the wall (88.4% vs. 14.0%, P < 0.0001) in a greater proportion of successful blebs than ASOCT. SDOCT showed the bleb cavity (23.3% vs. 48.8%, P = 0.02), scleral flap (34.9% vs. 90.7%, P < 0.0001), subflap space (20.9% vs . 72.1%, P < 0.0001) and ostium (9.3% vs. 88.4%, P < 0.0001) in fewer successful blebs than ASOCT. The internal ostium was not visualized in any failed bleb using SDOCT, whereas ASOCT showed the ostium in 87.5% of failed blebs ( P = 0.001). SDOCT showed cystic spaces in the bleb wall in a greater proportion of successful blebs than failed blebs (88.4% vs. 37.5%, P = 0.005).
Conclusions: SDOCT imaging was able to show fine superficial features in the bleb wall. However, SDOCT had limited clinical utility in that it did not provide useful information about deep features such as flap position, bleb cavity formation or patency of the subflap space and internal ostium. 相似文献
49.
在当前医学教育持续变革的背景中,医学教师的专业发展成为广泛关注的焦点.为了解目前美国以提高教师的教学技能为目标的教师专业发展(faculty development,FD)活动的参与率、课程设计、教学方法和评估策略等情况,美国约翰·霍普金斯大学预防、流行病学和临床研究中心采取邮件调查的方式,对美国277家教学医院进行了调查. 相似文献
50.