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排序方式: 共有422条查询结果,搜索用时 15 毫秒
101.
Mustafa G Khan IU Ashraf M Afzal I Shahzad SA Shafiq M 《Bioorganic & medicinal chemistry》2012,20(8):2535-2539
The present study describes a convenient method for the synthesis of new lipoxygenase inhibitors, 4-(toluene-4-sulfonylamino)-benzoic acids from p-amino benzoic acid. Reaction of p-amino benzoic acid with p-toluenesulfonyl chloride provided thirteen N- and O-alkylation products 4a-4m in moderate to good yields. Lipoxygenase inhibition of newly formed sulfonamide derivatives was investigated and some of these compounds 4m, 4g, 4e, 4f and 4j showed good lipoxygenase inhibitory activities with IC(50) values ranged between 15.8 ± 0.57 and 91.7 ± 0.61 μmol whilst all other compounds exhibited mild anti-lipoxygenase activities with IC(50) values ranged between 139.2 ± 0.75 and 232.1 ± 0.78 μmol. N-alkylated products were more active against the enzyme than O-alkylated or both N- and O-alkylated ones. All synthesized sulfonamides were recrystallized in chloroform to give these title compounds which were characterized using FTIR, (1)H NMR, (13)C NMR, elemental analysis and single crystal X-ray diffraction techniques. 相似文献
102.
Muhammad HAMAYUN Sumera Afzal KHAN 《云南植物研究》2006,28(6):665-668
The traditional herbal medicine bequeathed fromgenerationto generationis richin domestic recipes andcommunal practice . Encompassing concepts and meth-ods for the protection and restoration of health, tradi-tional medicine has served as a fount of alternativemedicine , newpharmaceuticals , and healthcare prod-ucts. The best known examples of traditional medi-cine , differing in concept and protocol , are well-de-veloped systems such as acupuncture , Unani systemand ayurvedic medicine that have… 相似文献
103.
OBJECTIVE: To evaluate the utility of rapid intraoperative crush smear cytologic diagnosis of central and peripheral nervous system lesions and to determine the accuracy and relevance of the accuracy of the intraoperative cytologic diagnosis when compared to the final paraffin section diagnosis. STUDY DESIGN: The crush (squash) smear technique was introduced at Sher-i-Kashmir Institute of Medical Sciences in May 2003. The 8 months of 2003 were used for standardization of the procedure. In 2004, 151 patients with open neurosurgical specimens or stereotactic biopsies were diagnosed intraoperatively by crush smears, and the diagnosis was compared with final diagnosis on paraffin sections of the same tissue samples. No supplementation of frozen sections was used. RESULTS: Of 151 cases, 144 were diagnosed accurately intraoperatively by crush smear cytology when compared with the respective paraffin section diagnoses. The diagnostic accuracy attained was 95.36%. Each case was diagnosed within 10 minutes after receipt of sample. Neurosurgical procedure (open or stereotaxy) did not affect diagnostic accuracy. CONCLUSION: In the expert hands of a pathologist with good exposure neurosurgical specimens, crush smear cytology is an accura and reliable procedure for the intraoperative diagnosis central nervous system tumors. 相似文献
104.
105.
Khaliq S Akhtar K Afzal Ghauri M Iqbal R Mukhtar Khalid A Muddassar M 《Microbiological research》2009,164(4):469-477
Tylosin is a macrolide antibiotic used as veterinary drug and growth promoter. Attempts were made for hyper production of tylosin by a strain of Streptomyces fradiae NRRL-2702 through irradiation mutagenesis. Ultraviolet (UV) irradiation of wild-type strain caused development of six morphologically altered colony types on agar plates. After screening using Bacillus subtilis bioassay only morphological mutants indicated the production of tylosin. An increase of 2.7±0.22-fold in tylosin production (1500 mg/l) in case of mutant UV-2 in complex medium was achieved as compared to wild-type strain (550 mg/l). Gamma irradiation of mutant UV-2 using 60Co gave one morphologically altered colony type γ-1, which gave 2500 mg/l tylosin yield in complex medium. Chemically defined media promoted tylosin production upto 3800 mg/l. Maximum value of qp (3.34 mg/gh) was observed by mutant γ-1 as compared to wild strain (0.81 mg/gh). Moreover, UV irradiation associated changes were unstable with loss of tylosin activity whereas mutant γ-1 displayed high stability on subsequent culturing. 相似文献
106.
Khan SA Hamayun M Kim HY Yoon HJ Seo JC Choo YS Lee IJ Kim SD Rhee IK Kim JG 《Biotechnology letters》2009,31(2):283-287
Plant growth-promoting endophytic fungi with gibberellin-producing ability were isolated from the roots of Carex kobomugi Ohwi, a common sand-dune plant, and bioassayed for plant growth-promotion. A new strain, Arthrinium phaeospermum KACC43901, promoted growth of waito-c rice and Atriplex gemelinii. Analysis of its culture filtrate showed the presence of bioactive GA1 (0.5 ng/ml), GA3 (8.8 ng/ml), GA4 (4.7 ng/ml) and GA7 (2.2 ng/ml) along with physiologically inactive GA5 (0.4 ng/ml), GA9 (0.6 ng/ml), GA12 (0.4 ng/ml), GA15 (0.4 ng/ml), GA19 (0.9 ng/ml) and GA24 (1.8 ng/ml). The fungal isolate was identified through sequence homology and phylogenetic analysis of 18S rDNA (internal
transcribed region).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
107.
108.
Samreen Kazi J. Shultz J. Afzal Rizwan Hashmi Mohammed Jasim Jason Bond Prakash R. Arelli David A. Lightfoot 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):633-644
Soybean [Glycine max (L.) Merr.] cultivars varied in their resistance to different populations of the soybean cyst nematode (SCN), Heterodera glycines, called HG Types. The rhg1 locus on linkage group G was necessary for resistance to all HG types. However, the loci for resistance to H. glycines HG Type 1.3- (race 14) and HG Type 1.2.5- (race 2) of the soybean cyst nematode have varied in their reported locations.
The aims were to compare the inheritance of resistance to three nematode HG Types in a population segregating for resistance
to SCN and to identify the underlying quantitative trait loci (QTL). ‘Hartwig’, a soybean cultivar resistant to most SCN HG
Types, was crossed with the susceptible cultivar ‘Flyer’. A total of 92 F5-derived recombinant inbred lines (RILs; or inbred
lines) and 144 molecular markers were used for map development. The rhg1 associated QTL found in earlier studies were confirmed and shown to underlie resistance to all three HG Types in RILs (Satt309;
HG Type 0, P = 0.0001 R
2 = 22%; Satt275; HG Type 1.3, P = 0.001, R
2 = 14%) and near isogeneic lines (NILs; or iso-lines; Satt309; HG Type 1.2.5-, P = 0.001 R
2 = 24%). A new QTL underlying resistance to HG Type 1.2.5- was detected on LG D2 (Satt574; P = 0.001, R
2 = 11%) among 14 RILs resistant to the other HG types. The locus was confirmed in a small NIL population consisting of 60
plants of ten genotypes (P = 0.04). This QTL (cqSCN-005) is located in an interval previously associated with resistance to both SDS leaf scorch from
‘Pyramid’ and ‘Ripley’ (cqSDS-001) and SCN HG Type 1.3- from Hartwig and Pyramid. The QTL detected will allow marker assisted
selection for multigenic resistance to complex nematode populations in combination with sudden death syndrome resistance (SDS)
and other agronomic traits. 相似文献
109.
Sumra Afzal Mahjabeen Saleem Riffat Yasmin Mamoona Naz Muhammad Imran 《Molecular biology reports》2010,37(4):1717-1723
Consistent with its precloning characterization from the cellulolytic Bacillus sp., β-1,4-endoglucanase purified from the recombinant E. coli exhibited maximum activity at 60°C and pH 7.0. It was highly specific for CMC hydrolysis, with stability up to 70°C and over
a pH range of 6.0–8.0. The K
m and V
max values for CMCase activity of the enzyme were 4.1 mg/ml and 25 μmole/ml min−1, respectively. The purified enzyme was a monomer of 65 kDa, as determined by SDS-PAGE. The presence of sucrose and IPTG in
fermentation media increased the endoglucanase activity of the recombinant enzyme to 5.2-folds as compared with that of the
actual one. 相似文献
110.
Muhammad Naeem Anjum William Parker Russell Ruo Muhammad Afzal 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2010,26(1):38-43
The aim of this study was to use different gamma histogram criteria for the comparison of planned dose with irradiated dose distribution and find that what percent of pixels passing a certain criteria imitate a good quality plan. The dose was calculated for 156 patients by inverse planning optimization using the Corvus treatment planning system. Gafchromic films in combination with 2571 0.6 cm3 Farmer type ionization chamber and Farmer 2570/1 electrometer from NE Technology were used to measure the delivered dose in solid water phantom. All the measurements were performed on Varian CL21EX linear accelerator (Varian Medical Systems, Palo Alto, CA) fitted with a Millennium 120 leaf collimator. In this study the mean value of the percent of passing pixels within the region of interest under the criterion of 3% DD and 3 mm DTA is 90.2 ± 7.1% for head and neck cases and 92.2 ± 5.8% for non-head and neck cases. If we choose the criteria of 3% DD and 3 mm DTA then 96.3% head and neck plans have the percent of passing pixels ≥ 75% and 95.1% non-head and neck plans have the percent of passing pixels ≥ 80%. It is evident from the results of this study that the criterion of 5% DD and 3 mm DTA with the percent of passing pixels ≥ 90 for non-head and neck cases while the percent of passing pixels ≥ 85 for head and neck cases endorse that a plan is good. The results of this study may be useful for other institutions which use verification software and EBT films for patient specific IMRT QA. 相似文献