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81.
Fly ash (FA) from coal in Orissa (India) was used for amending soil at levels equivalent to 0, 1, 2.5, 5, 10 and 15 metric
tons per ha in which, rice was grown and elemental residues of amended soil and plant parts were enumerated. FA amendments
caused significant improvement in soil quality and germination percentage of rice seeds. Growth (shoot length, leaf area and
pigment composition) and yield (panicle length, seeds per panicle, seed weight and yield per plant) of rice increased with
an increase in FA amendments. Catalase and peroxidase activities of young leaves increased initially in plants cultivated
at lower FA levels but declined sharply at higher FA levels while the protein content of seeds improved at higher FA levels.
Sodium content of rice-roots did not change with FA amendments but the contents of K, P, Mn, Ni, Co, Pb, Zn, Cu, Cr, and Cd
showed a progressive increase. Seeds of plants grown in FA amended soils accumulated Cu, Pb, Cr and Cd in amounts below allowable
limits. Based on the data obtained we found that flooded-rice soil amended at 10 metric tons FA per ha level of FA not only
improved the physical properties of the soil but also contributed to better growth and yield of rice. 相似文献
82.
Background
Nasopharyngeal carcinoma (NPC) and other head and neck cancer (HNCA) types show a great epidemiological variation in different regions of the world. NPC has multifactorial etiology and many interacting risk factors are involved in NPC development mainly Epstein Barr virus (EBV). There is a need to scrutinize the complicated network of risk factors affecting NPC and how far they are different from that of other HNCA types.Methods
122 HNCA patients and 100 control subjects were studied in the region of the Middle East. Three types of HNCA were involved in our study, NPC, carcinoma of larynx (CL), and hypopharyngeal carcinoma (HPC). The risk factors studied were the level of EBV serum IgG and IgA antibodies measured by ELISA, age, sex, smoking, alcohol intake, histology, and family history of the disease.Results
EBV serum level of IgG and IgA antibodies was higher in NPC than CL, HPC, and control groups (p < 0.01). NPC was associated with lymphoepithelioma (LE) tumors, males, regular alcohol intake, and regular smoking while CL and HPC were not (p < 0.05). CL and HPC were associated with SCC tumors (p < 0.05). Furthermore, NPC, unlike CL and HPC groups, was not affected by the positive family history of HNCA (p > 0.05). The serum levels of EBV IgG and IgA antibodies were higher in LE tumors, regular smokers, younger patients, and negative family history groups of NPC patients than SCC tumors, non-regular smokers, older patients and positive family history groups respectively (p < 0.05) while this was not found in the regular alcoholics (p > 0.05).Conclusion
It was concluded that risk factors of NPC deviate much from that of other HNCA. EBV, smoking, alcohol intake, LE tumors, male patient, and age > 54 years were hot risk factors of NPC while SCC and positive family history of the disease were not. Earlier incidence, smoking, LE tumors, and negative family history of the disease in NPC patients were associated much clearly with EBV. It is proposed that determining the correct risk factors of NPC is vital in assigning the correct risk groups of NPC which helps the early detection and screening of NPC. 相似文献83.
84.
The pulmonary arterial anatomy in 44 patients with Takayasu's arteritis was examined by intravenous digital subtraction angiography (IV-DSA) on an outpatient basis using centrally delivered, small-volume, bolus injections of an ionic, water soluble contrast medium. Diagnostic pulmonary angiograms were obtained in 42 patients (95.4%) without complication. Angiographically evident pulmonary arterial involvement was seen in six patients (14.3%). The pulmonary involvement was not suspected clinically in any patient and the chest radiographs were abnormal in only two patients (33%). The angiographic spectrum of systemic arterial involvement was the same irrespective of the presence or absence of pulmonary arterial involvement. The pulmonary arterial pressures were measured in two patients with abnormal pulmonary angiograms and were found normal. Follow up IV-DSA in one of these patients 16 months after immuno-suppressive therapy showed no change in the pulmonary angiographic picture. 相似文献
85.
86.
BACKGROUND: Acral lentiginous melanoma (ALM) is a subtype of melanoma initially described only two and half decades ago, but well-recognized by dermatologists today. However, several areas of controversy surround this entity. OBJECTIVE: The primary aims of this article are to review the literature, highlight recent advances, and review some of the ongoing controversies in ALM. METHODS: A review of the English language literature was performed. RESULTS: Controversy continues to surround ALM, particularly in regard to diagnostic histologic and clinical criteria. This leads to difficulties when reviewing studies that evaluate the epidemiology, etiology, and prognosis of ALM. CONCLUSION: Progress in understanding ALM requires the development of standardized diagnostic criteria. 相似文献
87.
88.
Sravya Taneeru Venkateswara Rao Guttikonda Rajani Korlepara Rajasekhar Gaddipati Vinay Kumar Kundoor 《Journal of maxillofacial and oral surgery》2017,16(2):253-257
Calcifying epithelial odontogenic tumour also known as Pindborg tumour, is a rare benign odontogenic neoplasm of locally aggressive behavior. It is thought to arise from the epithelial element of the enamel origin which are reminiscent of the cells in the stratum intermedium layer of enamel organ in tooth development. The tumour is characterized histologically by the presence of polygonal epithelial cells, calcifications and eosinophilic deposits resembling amyloid. Non-calcifying epithelial odontogenic tumours are very rare and unusual. Only five cases have been reported in the English literature till date. Here, we present an additional case of non calcifying type along with a review of previously reported cases. It has a much lower recurrence and malignant transformation rate. 相似文献
89.
V Devi K Ramnarayan RR Abraham V Pallath A Kamath S Kodidela 《Journal of postgraduate medicine》2015,61(3):163-168
Background:
Participation in research during undergraduate studies may increase students’ interest in research and inculcate research essentials in them.Aims:
The purpose of this study was to evaluate the effectiveness of the mentored student project (MSP) program.Settings and Design:
In the MSP program, students in groups (n = 3 to 5) undertook a research project, wrote a scholarly report, and presented the work as a poster presentation with the help of a faculty mentor. To begin with, the logic model of the program was developed to identify short-term outcomes of the program on students, mentors, and the institution. A quasi-experimental design was used to measure the outcomes.Materials and Methods:
A mixed method evaluation was done using a newly-developed questionnaire to assess the impact of the MSP on students’ attitude, a multiple-choice question (MCQs) test to find out the impact on students’ knowledge and grading of students’ project reports and posters along with a survey to check the impact on skills. Students’ satisfaction regarding the program and mentors’ perceptions were collected using questionnaires. Evidence for validity was collected for all the instruments used for the evaluation.Statistical Analysis:
Non-parametric tests were used to analyze data. Based on the scores, project reports and posters were graded into A (>70% marks), B (60-69% marks), and C (<59% marks) categories. The number of MSPs that resulted in publications, conference presentation and departmental collaborations were taken as impact on the institution.Results:
Students’ response rate was 91.5%. The students’ attitudes regarding research changed positively (P = 0.036) and score in the MCQ test improved (P < 0.001) after undertaking MSP. Majority of project reports and posters were of grade A category. The majority of the items related to skills gained and satisfaction had a median score of 4. The MSPs resulted in inter-departmental and inter-institutional collaborations, 14 publications and 15 conference presentations. An area for improvement noted was to have the MSP implemented in the curriculum without increasing students’ overall workload and stress.Conclusion:
The study identified strengths and weaknesses of the MSP program. Our model of undergraduate research project may be incorporated in undergraduate medical programs to foster positive attitude and knowledge base about scientific research and to instil research skills among students.KEY WORDS: Attitude, knowledge, mentored, outcome, research, skills, student 相似文献90.
H S Wasir V Dev U Kaul M Rajani S Mukherjee S Sharma M L Bhatia 《Clinical cardiology》1988,11(7):461-465
A total of 1150 consecutive patients (1052 males and 98 females; age 51.2 +/- 10.1 years) with suspected coronary artery disease (Group I) were subjected to fluoroscopy for detection of coronary artery calcification (CAC) and coronary angiography. Another group (Group II) of 120 patients (95 males and 25 females; age 51.4 +/- 9.4 years) catheterized for cardiac diseases other than coronary artery disease (CAD) were subjected to the same protocol of fluoroscopy and coronary angiography to exclude incidental CAD in view of their age. CAC was present in 240 patients (20.0%) in Group I. Of these, 200 (83.4%) had triple-vessel disease (TVD); 20 (8.3%) had double-vessel disease (DVD); 19 (7.9%) had single-vessel disease (SVD); and 37 (15.4%) patients had left main coronary disease (LMCAD). Only one of these patients had insignificant CAD considered as "normal" coronary arteries (NC). Incidence of LMCAD, TVD, DVD, SVD, and NC in patients without CAC was 4.4%, 56.3%, 18.2%, 14.0%, and 11.5%, respectively. Incidence of CAC in patients with LMCAD, TVD, DVD, SVD, and NC was 48.1%, 28.1%, 10.8%, 13.0%, and 1.0% respectively. In Group II (n = 120), 24 patients (20%) had CAD, CAC was present in 5 patients with CAD (20.9%), and in two patients without CAD (2%). CAC is relatively uncommon in Indian CAD patients. Its presence, however, indicates severe multivessel disease. 相似文献