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1.
Thirty rhizobacteria isolated from maize grown in Pakistani and Indonesian soils were evaluated for their morphological characteristics, nitrogen fixation, P-solubilization, indole acetic acid (IAA) and siderophores production. Nitrogenase activity was detected in nineteen isolates ranging from 21.8-3624 n moles C2H4 produced/h/mg protein. Most of the isolates produced IAA, ten were capable of siderophore production while four were P-solubilizers. Ultrastructural studies of Pseudomonas sp. F14 indicated characteristic rhizospheric colonization within 48 h that was observed to change considerably with the passage of time from few bacteria to micro colonies. Random amplified polymorphic DNA (RAPD) analysis of 30 bacterial strains using 30 oligonucleotide primers resulted in considerable level of genetic diversity, with genetic distance ranging from 2-16%. Indonesian isolates were found to be more diverse as compared to Pakistani isolates. The characterization and screening of rhizobacteria of maize rhizosphere has helped in selection of isolates F7, LS-1, 3.1.1.C, F2, F3 and F13 as superior strains for use as bioinoculant. Moreover isolate F14 identified, as Pseudomonas fulgida by partial 16S rRNA sequence analysis is a novel strain regarding its tremendous potentials for inoculum production to enhance the yield of maize. 相似文献
2.
Ruck NF Hafeez M Manzur S Nasir F Rivers K Prozesky D 《Journal of health & population in developing countries》1999,2(1):78-87
Pakistan's public sector is organized in a federal system with many management and planning functions devolved to the 4 provincial governments. Provincial health secretariats lead on most policy and planning decisions for health services. The provinces employ health personnel, although the national Public Service Commission controls some key aspects of human resources management. Reporting the findings of a training needs assessment (TNA) for health personnel in the provincial health services of Punjab, the authors show how TNA can be used systematically to improve the quality of health professional training. They also discuss the extent to which better training could contribute to improved health management capacity in Pakistan, and describe the context and problems of Pakistan's health services, focusing upon management capacity, and the methods and results of a training needs assessment conducted to address the problems. A final section covers the usefulness of the TNA method in Pakistan and its applicability to other countries. Moreover, the implications of decentralization and the problems of preparing training plans in the absence of decentralized structures are discussed. 相似文献
3.
Wenchao Xue Hua Li Roberto Dugnani Hafeez Ur Rehman Chunmei Zhang Yujie Chen Hezhou Liu 《RSC advances》2018,8(23):12494
In this study, a lead zirconate titanate (PZT)/in situ polymerized polyurethane (PU) composite with three-dimensional (3D) reduced graphene oxide (rGO) as the conductive phase was prepared and the potential of 3D rGO to enhance the damping properties was investigated. The conductivity and damping properties of the composite were systematically investigated. The results show that the conductive threshold of the composite is reached at a very low rGO content of about 0.7 wt% by using the 3D rGO structure. The best damping performance of the piezoelectric damping composite is achieved at the conductive threshold, where the loss factor is 0.22 (almost 41%) higher and the temperature range where tan δ ≥ 0.3 is 13.2 °C (almost 84%) wider than those of the PU matrix. A composite consisting of only PU and rGO sheets without the 3D structure was prepared for comparison. The conductive threshold of this composite is more than 0.9 wt% and the highest tensile strength is 5.63 MPa when the rGO content is 0.6 wt%, indicating that the 3D structure reduces the use of the conductive phase and does not significantly affect the tensile strength of the matrix.Piezoelectric damping composite with 3D rGO as the conductive phase that possesses good damping properties with the conductive threshold as low as 0.7 wt%. 相似文献
4.
Zulfiqar A. Bhutta Assad Hafeez 《Health research policy and systems / BioMed Central》2015,13(Z1):S49
Pakistan faces huge challenges in meeting its international obligations and agreed Millennium Development Goal targets for reducing maternal and child mortality. While there have been reductions in maternal and under-5 child mortality, overall rates are barely above secular trends and neonatal mortality has not reduced much. Progress in addressing basic determinants, such as poverty, undernutrition, safe water, and sound sanitary conditions as well as female education, is unsatisfactory and, not surprisingly, population growth hampers economic growth and development across the country. The devolution of health to the provinces has created challenges as well as opportunities for action. This paper presents a range of actions needed for change within the health and social sectors, including primary care, social determinants, strategies to reach the unreached, and accountability. 相似文献
5.
Elvis Cami Travis Tagami Gilbert Raff Michael J. Gallagher Austin Fan Adam Hafeez Stacy J. Willner Priscilla Sigua Arce Julie George Abhay Bilolikar Kavitha Chinnaiyan Robert D. Safian 《Journal of Cardiovascular Computed Tomography》2021,15(2):114-120
BackgroundValues of fractional flow reserve (FFRCT) by coronary computed tomography angiography (CTA) decline from the ostium to the terminal vessel, irrespective of stenosis severity. The purpose of this study is to determine if the site of measurement of FFRCT impacts assessment of ischemia and its diagnostic performance relative to invasive FFR (FFRINV).Methods1484 patients underwent FFRCT; 1910 vessels were stratified by stenosis severity (normal; <25%, 25–50%, 50–70%, and >70% stenosis). The rates of positive FFRCT (≤0.8) were determined by measuring FFRCT from the terminal vessel and from distal-to-the-lesion. Reclassification rates from positive to negative FFRCT were calculated. Diagnostic performance of FFRCT relative to FFRINV was evaluated in 182 vessels using linear regression, Bland Altman analysis, and receiver operating characteristic (ROC) curves.ResultsPositive FFRCT was identified in 24.9% of vessels using terminal vessel FFRCT and 10.1% using FFRCT distal-to-the-lesion (p ?< ?0.001). FFRCT obtained distal-to-the-lesion resulted in reclassification of 59.6% of positive terminal FFRCT to negative FFRCT. Relative to FFRINV, there were improvements in specificity (50% to 86%, p ?< ?0.001), diagnostic accuracy (65% to 88%, p ?< ?0.001), positive predictive value (50% to 78%, p ?< ?0.001), and area-under-the-curve (AUC, 0.83 to 0.91, p ?< ?0.001) when FFRCT was measured distal-to-the-lesion.ConclusionFFRCT values from the terminal vessel should not be used to assess lesion-specific ischemia due to high rates of false positive results. FFRCT measured distal-to-the-lesion improves the diagnostic performance of FFRCT relative to FFRINV, ensures that FFRCT values are due to lesion-specific ischemia, and could reduce the rate of unnecessary invasive procedures. 相似文献
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S. El-Sherry T. Rathinam M. A. Hafeez M. E. Ogedengbe H. D. Chapman J. R. Barta 《Parasitology research》2014,113(3):1135-1146
For the purpose of re-describing the Eimeria species that infect the turkey (Meleagris gallopavo) and to establish benchmark biological information linked to genetic markers for each species, a strain of Eimeria meleagrimitis Tyzzer 1929 was obtained from a litter sample from a turkey farm in Minnesota, USA in 2008. Multiple pure lines were derived by infecting turkey poults with a single oocyst; one of these lines was then used to re-describe biological and morphological features of E. meleagrimitis in the turkey and to designate a neotype of E. meleagrimitis in the turkey. Oocyst morphometrics of this line matched those of this species as originally described by Tyzzer (Am J Hyg 10:269–383, 1929). Three asexual generations of merogony (the first generation of meronts large in size and the second and third generations small) were detected in the intestines before the onset of gametogony; no developmental stages were detected in the cecal pouches. No mortality was induced by this line of E. meleagrimitis even when turkey poults were infected with high doses of oocysts (up to 5?×?105 oocysts/bird) and despite the ability of E. meleagrimitis to induce severe mucosal damage in the upper and middle duodenum. Macroscopic lesions were characterized to provide a graded lesion scoring guide that should assist assessment of the severity of infections with this species in infected turkeys. The pathogenicity of the strain was investigated, and a significant reduction in weight gain and feed conversion ratio was observed with doses of 104 oocysts/bird or more. The maximum yield of oocysts in the feces was obtained when birds were inoculated with 5?×?103 oocysts. 相似文献
9.
Meagan A. Barry Misha V. Koshelev Grace S. Sun Sarah J. Grekin Charles E. Stager A. Hafeez Diwan Carina A. Wasko Kristy O. Murray Laila Woc-Colburn 《The American journal of tropical medicine and hygiene》2014,91(2):345-347
Cutaneous leishmaniasis is rarely seen in the United States. Four Cuban immigrants traveled along the same route at different times from Cuba to Ecuador, then northward, including through the Darién Jungle in Panama. These patients had chronic ulcerative non-healing skin lesions and were given a diagnosis of leishmaniasis.Leishmaniasis is a vector-borne disease caused by the protozoan parasite of the genus Leishmania and is spread by the bite of sand flies from the sub-family Phlebotominae.1 There are various clinical manifestations of leishmaniasis, including cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis, and visceral leishmaniasis. Cutaneous leishmaniasis occurs at the site of the bite, with lesions forming weeks to months later starting with a papule, which then develops into a nodule or plaque-like lesion and progresses to a painless ulceration with an indurated border.We report four cases of CL caused by Leishmania (Viannia) panamensis in Cuban immigrants who traveled through the Darién Gap Jungle between Colombia and Panama on their journey north to the United States. This region has been shown to have high transmission rates of leishmaniasis,2 and, in 2012, Panama experienced an outbreak beyond expected endemic rates.3 This case series highlights a previously underappreciated immigration route to the United States for Cubans and the need to include leishmaniasis as a differential diagnosis for non-healing skin ulcers in this patient population.During May 2012–April 2013, four persons who had recently immigrated to the United States from Cuba came to the National School of Tropical Medicine at Baylor College of Medicine''s (BCM) Tropical Medicine Clinic for non-healing skin ulcers. All four persons reported a similar route of travel from Cuba to Texas (Figure 1), although at different times. Each person began their journey by flying to Quito, Ecuador, where they then traveled by bus through Colombia, passing through the cities of Pasto and Cali to Quibdo. In Quibdo, they took a short flight to Bahia Solano, Colombia, where a boat ride then transported them to Punta Ardita near the Panama border. They then traveled by foot through the thick jungle in Darién, Panama, for 5–15 days. During this time, they slept outdoors and reported numerous insect bites. Once through the Darién area, they traveled northward until they entered the United States at the Mexican border.Open in a separate windowFigure 1.Map showing immigration route of a cluster of Cuban patients with cutaneous leishmaniasis caused by Leishmania (V.) panamensis. Note the travel by foot through the thick jungle of the Darién National Park, Panama, where they likely contracted the disease.Once in the United States, the four persons sought medical care at outside clinics for skin lesions that had developed within two months after they passed though the Darién. They were treated for presumed infection with Staphylococcus aureus. The antibiotics had no therapeutic effect, and the lesions continued to grow and develop into non-healing, painless ulcers with accompanying satellite lesions. Once in Houston, Texas, the four persons were directed to the Department of Dermatology at BCM (Patient Age, years/sex Lesion location; size; presence of satellite lesions (+/−) Diagnosis and pathogen Duration of disease before initiation of treatment Treatment course 1 38/F Proximal right posterior arm; 5 cm; (+) CL L. (V.) panamensis 3 months AmBisome (days 1–5, 14, 21) 2 46/M Distal left forearm; 2 lesions: 4 cm and 3 cm; (+) CL L. (V.) panamensis 2 months AmBisome (days 1–5, 14, 21); then itraconazole (daily, 30 days) 3 43/M Vertex of scalp, 8 more lesions on eyes, legs, and torso; 5 cm, other lesions 1 cm; (+) CL L. (V.) panamensis 2 weeks AmBisome (days 1–5); then pentostam (daily, 20 days) 4 43/F Left malar area; 1.5 cm; (+) CL L. (V.) panamensis 3 months AmBisome (days 1–5, 14)