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排序方式: 共有313条查询结果,搜索用时 15 毫秒
91.
Islam MS Jahid MI Rahman MM Rahman MZ Islam MS Kabir MS Sack DA Schoolnik GK 《Microbiology and immunology》2007,51(4):369-379
The role of biofilm as a microenvironment of plankton-associated Vibrio cholerae was investigated using plexiglass as a bait. A total of 72 biofilm samples were tested using culture, direct fluorescent antibody (DFA) and molecular techniques following standard procedures. Culturable V. cholerae (smooth and rugose variants) were isolated from 33% of the samples. V. cholerae O1 were detected by FA technique throughout the year except April and June. All V. cholerae O1 isolates were positive for tcpA, ctxA and ace genes while V. cholerae non-O1, non-O139 isolates lacked these genes. V. cholerae O1 (both Inaba and Ogawa) strains had identical ribotype pattern (R1), but V. cholerae non-O1, non-O139 had different ribotype patterns. All V. cholerae O1 strains were resistant to vibrio-static compound (O/129). All V. cholerae O1 except one were resistant to trimethoprime-sulphamethoxazole, streptomycin, nalidixic acid and furazolidone but sensitive to ciprofloxacin, and tetracycline. This study indicates that plexiglass can act as a bait to form biofilm, a microenvironment that provides shelter for plankton containing V. cholerae in the aquatic environment of Bangladesh. 相似文献
92.
93.
Mohammed Wasim Siddiqui Moasosang Longkumer Md. Shamsher Ahmad Kalyan Barman Pran Krishna Thakur Jahangir Kabir 《Acta Physiologiae Plantarum》2014,36(12):3115-3122
Sapota is cultivated in many countries of tropical and subtropical climate. It is delicious, nutritive, and commercially grown mainly for fresh consumption. Postharvest life of sapota is very short due to its highly perishable nature and other many reasons such as quick ripening, faster senescence, rapid loss of moisture, microbial spoilage, and fruit sensitivity to cold storage. To maintain and/or increase the shelf life of sapota, proper postharvest management is required. Unfortunately, very little work has been done so far, with limited success, leaving scarce literature published on postharvest management technologies of sapota. Different pre and postharvest treatments to reduce metabolic activity and quality loss have been suggested. Moreover, proper storage temperature and packaging may be used to increase the shelf life of fruits. This review explores the postharvest technologies adopted to enhance the shelf life of sapota during storage and distribution channel. 相似文献
94.
Md Golam Kabir Md Monsor Rahman Nazim Uddin Ahmed Md Fakruddin Saiful Islam Reaz Mohammad Mazumdar 《Biological research》2014,47(1)
Background
This study was subjected to investigate different pharmacological properties of ethanol extract of Solena amplexicaulis root.Results
The extract contains flavonoid, alkaloid, saponin and steroid compounds. The extract exhibited excellent antioxidant activity in DPPH radical scavenging activity. The extract also showed potent activity in brine shrimp lethality bioassay. The LC50 value was found to 44.677 μg/ml. The extract showed better anti-bacterial activity against gram-negative bacteria. In antifungal assay, the maximum 79.31% of anti-mycotic activity was observed against Aspergillus ochraceus while minimum 44.2% against Rhizopus oryzae. MIC value ranged between 1500–3000 μg/ml. The extract was found moderately toxic with a 24-hr LD50 value of 81.47 mg/kg in Swiss albino mice. The degree of inhibition by the ethanolic extract of the root was found less than that of standard analgesic drug diclofenac sodium. The extract also showed moderate anti-inflammatory and antinociceptive activity and anti-diabetic property. Reducing power of the extract was comparable with standard ascorbic acid. Moderate in vitro thrombolytic activity, lipid peroxidation inhibition property, metal chelating ability and stress-protective activity was also observed.Conclusion
Ethanol extract of Solena amplexicaulis root can be valuable for treatment of different diseases. 相似文献95.
Hans Goost Johannes Witten Andreas Heck Dariusch R. Hadizadeh Oliver Weber Ingo Gr?ff Christof Burger Mareen Montag Felix Koerfer Koroush Kabir 《PloS one》2012,7(10)
Introduction
Developments in telemedicine have not produced any relevant benefits for orthopedics and trauma surgery to date. For the present project study, several parameters were examined during assessment of x-ray images, which had been photographed and transmitted via cell phone.Materials and Methods
A total of 100 x-ray images of various body regions were photographed with a Nokia cell phone and transmitted via email or MMS. Next, the transmitted photographs were reviewed on a laptop computer by five medical specialists and assessed regarding quality and diagnosis.Results
Due to their poor quality, the transmitted MMS images could not be evaluated and this path of transmission was therefore excluded. Mean size of transmitted x-ray email images was 394 kB (range: 265–590 kB, SD ±59), average transmission time was 3.29 min ±8 (CI 95%: 1.7–4.9). Applying a score from 1–10 (very poor - excellent), mean image quality was 5.8. In 83.2±4% (mean value ± SD) of cases (median 82; 80–89%), there was agreement between final diagnosis and assessment by the five medical experts who had received the images. However, there was a markedly low concurrence ratio in the thoracic area and in pediatric injuries.Discussion
While the rate of accurate diagnosis and indication for surgery was high with a concurrence ratio of 83%, considerable differences existed between the assessed regions, with lowest values for thoracic images. Teleradiology is a cost-effective, rapid method which can be applied wherever wireless cell phone reception is available. In our opinion, this method is in principle suitable for clinical use, enabling the physician on duty to agree on appropriate measures with colleagues located elsewhere via x-ray image transmission on a cell phone. 相似文献96.
Ovarian cancer, one of inflammation-associated cancers, is the fifth leading cause of cancer deaths among women. Inflammation in the tumor microenvironment is associated with peritoneal tumor dissemination and massive ascites, which contribute to high mortality in ovarian cancer. Tumor suppressor p53 is frequently deleted or mutated in aggressive and high-grade ovarian cancer, probably aggravating cancer progression and increasing mortality. We therefore investigated the influence of p53 on proinflammatory chemokines in ovarian cancer cells. A PCR array of the chemokine network revealed that ovarian cancer cells with low or mutated p53 expression expressed high levels of proinflammatory chemokines such as CXCL1, 2, 3 and 8. Transient transfection of p53 into p53-null ovarian cancer cells downregulated proinflammatory chemokines induced by tumor necrosis factor-α (TNF), a proinflammatory cytokine abundantly expressed in ovarian cancer. Furthermore, p53 restoration or stabilization blocked TNF-induced NF-κB promoter activity and reduced TNF-activated IκB. Restoration of p53 increased ubiquitination of IκB, resulting from concurrently reduced proteasome activity followed by stability of IκB. A ubiquitination PCR array on restoration of p53 did not reveal any significant change in expression except for Mdm2, indicating that the balance between p53 and Mdm2 is more important in regulating NF-κB signaling rather than the direct effect of p53 on ubiquitin-related genes or IκB kinases. In addition, nutlin-3, a specific inducer of p53 stabilization, inhibited proinflammatory chemokines by reducing TNF-activated IκB through p53 stabilization. Taken together, these results suggest that p53 inhibits proinflammatory chemokines in ovarian cancer cells by reducing proteasomal degradation of IκB. Thus, frequent loss or mutation of p53 may promote tumor progression by enhancing inflammation in the tumor microenvironment. 相似文献
97.
98.
This paper presents a new ECG denoising approach based on noise reduction algorithms in empirical mode decomposition (EMD) and discrete wavelet transform (DWT) domains. Unlike the conventional EMD based ECG denoising approaches that neglect a number of initial intrinsic mode functions (IMFs) containing the QRS complex as well as noise, we propose to perform windowing in the EMD domain in order to reduce the noise from the initial IMFs instead of discarding them completely thus preserving the QRS complex and yielding a relatively cleaner ECG signal. The signal thus obtained is transformed in the DWT domain, where an adaptive soft thresholding based noise reduction algorithm is employed considering the advantageous properties of the DWT compared to that of the EMD in preserving the energy in the presence of noise and in reconstructing the original ECG signal with a better time resolution. Extensive simulations are carried out using the MIT-BIH arrythmia database and the performance of the proposed method is evaluated in terms of several standard metrics. The simulation results show that the proposed method is able to reduce noise from the noisy ECG signals more accurately and consistently in comparison to some of the stateof-the-art methods. 相似文献
99.
Can Homegardens Conserve Biodiversity in Bangladesh? 总被引:1,自引:0,他引:1
In managed landscapes, tree-dominated habitats often show promise for biodiversity conservation. In Bangladesh where natural forest cover is less than 10 percent, homegardens, which are maintained by at least 20 millions households, represent one possible strategy for biodiversity conservation. This study investigated the floristic and structural diversity of 402 homegardens from six regions across southwestern Bangladesh. All plants were censused, totaling 419 species (59% native), including six IUCN Red Listed. The median homegarden (800 m2 ) contained a mean of 34 species. Each region contained a mean of 293 species in a mean of 67 homegardens. A total of 49,478 individuals (107 per homegarden and 1003 per hectare) of trees and shrubs were counted from 45.2 ha total sampled area. Thus, significant botanical richness was exhibited in the homegardens across southwestern Bangladesh. However, most species were rare: 82 percent of all species including 189 native were found in 50 or fewer homegardens, and 63 species (36 native) were found in only one or two homegardens. Sixty percent of all tree and shrub species had 50 or fewer individuals each. Thus, whereas richness across the landscape was high, serious effort must be made to increase the populations of most species. We propose three main conservation activities: (1) awareness building; (2) protection of existing individuals of rare species; and (3) propagation. Overlaying all of these activities is the inclusion of local communities in the process, who were the ones to retain these species in homegardens in the first place, and the stakeholders who will determine whether homegardens indeed act as long-term repositories to biodiversity conservation. 相似文献
100.
Occurrence, seasonality and genetic diversity of Vibrio vulnificus in coastal seaweeds and water along the Kii Channel, Japan 总被引:1,自引:0,他引:1
Mahmud ZH Neogi SB Kassu A Mai Huong BT Jahid IK Islam MS Ota F 《FEMS microbiology ecology》2008,64(2):209-218
Vibrio vulnificus is a ubiquitous toxigenic bacterium found in a coastal environment but little is known about its occurrence and seasonality among seaweeds, which are widely consumed as seafood in Japan. Therefore, we have observed the bacterium's abundance in seawater and seaweed samples from three areas of the Kii Channel, Japan, during June 2003 to May 2004. A total of 192 samples were collected: 24 from each source in summer, autumn, winter and spring. The samples were selectively cultivated following the most probable number (MPN) technique. Vibrio vulnificus population ranged from 0 to 10(3) MPN 100 mL(-1) seawater or 10 g seaweeds; higher counts were observed during summer. The optimum temperature, salinity and pH for the bacterium were 20-24 degrees C, 24-28 p.p.t. and 7.95-8.15, respectively. However, seaweeds always contained higher V. vulnificus than seawater. Among 280 V. vulnificus strains, detected by species-specific colony hybridization and PCR, 78, 74, 11 and 16 were from seaweeds and 46, 42, 2 and 11 were from seawater during summer, autumn, winter and spring, respectively. Ribotyping of 160 selected strains revealed a higher genotypic diversity (18 patterns) among strains from seaweeds than from seawater (10 patterns). Seaweeds can thus act as a potential habitat for V. vulnificus and are more unsafe for consumption during summer. 相似文献