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41.
42.
Water soluble polysaccharides are currently finding increasing use as a basis material for plasma volume expander. In clinical setting it is desirable to have a precise knowledge of steric and chemical structure, since these affect the pharmacokinetics and pharmacology of plasma volume expander. Branch component of starch amylopectin is very similar in structure to glycogen, the reserve polysaccharide of animal and therefore is liable to be compatible with body tissue. The knowledge of weight average molecular mass, degree of branching, osmotic pressure and coil dimension are essential, since low molecular mass do not have desirable effect and large molar mass have undesirable effect. Assam Bora rice starch was characterized by polymer analysis for use as plasma volume expander. Characterization involves the determination of FTIR spectra, degree of branching by H1 NMR, osmotic pressure by internal measurement technique, establishment of Mark-Houwink relationship and determination of Molecular weight - viscosity relationship. 相似文献
43.
Population-based surveillance of typhoid fever in Egypt 总被引:1,自引:0,他引:1
Srikantiah P Girgis FY Luby SP Jennings G Wasfy MO Crump JA Hoekstra RM Anwer M Mahoney FJ 《The American journal of tropical medicine and hygiene》2006,74(1):114-119
Credible measures of disease incidence are necessary to guide typhoid fever control efforts. In Egypt, incidence estimates have been derived from hospital-based syndromic surveillance, which may not represent the population with typhoid fever. To determine the population-based incidence of typhoid fever in Fayoum Governorate (pop. 2,240,000), we established laboratory-based surveillance at five tiers of health care. Incidence estimates were adjusted for sampling and test sensitivity. Of 1,815 patients evaluated, cultures yielded 90 (5%) Salmonella Typhi isolates. The estimated incidence of typhoid fever was 59/100,000 persons/year. We estimate 71% of typhoid fever patients are managed by primary care providers. Multidrug-resistant (MDR) Salmonella Typhi (resistant to chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole) was isolated from 26 (29%) patients. Population-based surveillance indicates moderate typhoid fever incidence in Fayoum, and a concerning prevalence of MDR typhoid. The majority of patients are evaluated at the primary care level and would not have been detected by hospital-based surveillance. 相似文献
44.
Lehmann ML Selinski S Blaszkewicz M Orlich M Ovsiannikov D Moormann O Guballa C Kress A Truss MC Gerullis H Otto T Barski D Niegisch G Albers P Frees S Brenner W Thüroff JW Angeli-Greaves M Seidel T Roth G Dietrich H Ebbinghaus R Prager HM Bolt HM Falkenstein M Zimmermann A Klein T Reckwitz T Roemer HC Löhlein D Weistenhöfer W Schöps W Beg AE Aslam M Bánfi G Romics I Ickstadt K Schwender H Winterpacht A Hengstler JG Golka K 《Archives of toxicology》2010,84(12):967-978
Single nucleotide polymorphism (SNP) rs710521[A], located near TP63 on chromosome 3q28, was identified to be significantly associated with increased bladder cancer risk. To investigate the association of rs710521[A] and bladder cancer by new data and by meta-analysis including all published data, rs710521 was studied in 1,425 bladder cancer cases and 1,740 controls that had not been included in previous studies. Blood samples were collected from 1995 to 2010 in Germany (n?=?948/1,258), Hungary (n?=?262/65), Venezuela (n?=?112/190) and Pakistan (n?=?103/227) supplemented by a meta-analysis of 5,695 cases and 40,187 controls. Detection of a A/G substitution (rs710521) on chromosome 3q28, position 191128627 was done via fast real-time polymerase chain reaction (rt-PCR). Rs710521[A] is associated with increased risk in the unadjusted analysis (OR?=?1.21; 95% Cl?=?1.04-1.40; P?=?0.011) and in the recessive model adjusted for age, gender, smoking habits and ethnicity (OR?=?1.23; 95% Cl?=?1.05-1.44; P?=?0.010). No difference between individuals occupationally exposed versus not occupationally exposed to urinary bladder carcinogens was observed concerning the relevance of rs710521[A]. Similarly, rs710521[A] did not confer different susceptibility in smokers and non-smokers. Performing a meta-analysis of 5,695 cases and 40,187 controls including all published studies on rs710521, a convincing association with bladder cancer risk was obtained (OR?=?1.18; 95% Cl?=?1.12-1.25; P?0.0001). However, the odds ratio is relatively small. 相似文献
45.
Ericksen SS Cummings DF Teer ME Amdani S Schetz JA 《The Journal of pharmacology and experimental therapeutics》2012,342(2):472-485
In an effort to delineate how specific molecular interactions of dopamine receptor ligand classes vary between D2-like dopamine receptor subtypes, a conserved threonine in transmembrane (TM) helix 7 (Thr7.39), implicated as a key ligand interaction site with biogenic amine G protein-coupled receptors, was substituted with alanine in D2 and D4 receptors. Interrogation of different ligand chemotypes for sensitivity to this substitution revealed enhanced affinity in the D4, but not the D2 receptor, specifically for substituted benzamides (SBAs) having polar 4- (para) and/or 5- (meta) benzamide ring substituents. D4-T7.39A was fully functional, and the mutation did not alter the sodium-mediated positive and negative allostery observed with SBAs and agonists, respectively. With the exception of the non-SBA ligand (+)-butaclamol, which, in contrast to certain SBAs, had decreased affinity for the D4-T7.39A mutant, the interactions of numerous other ligands were unaffected by this mutation. SBAs were docked into D4 models in the same mode as observed for eticlopride in the D3 crystal structure. In this mode, interactions with TM5 and TM6 residues constrain the SBA ring position that produces distal steric crowding between pyrrolidinyl/diethylamine moieties and D4-Thr7.39. Ligand-residue interaction energy profiles suggest this crowding is mitigated by substitution with a smaller alanine. The profiles indicate sites that contribute to the SBA binding interaction and site-specific energy changes imparted by the D4-T7.39A mutation. Substantial interaction energy changes are observed at only a few positions, some of which are not conserved among the dopamine receptor subtypes and thus seem to account for this D4 subtype-specific structure-activity relationship. 相似文献
46.
47.
The aim of the study was to compare the long-term efficacy of high versus low frequency repetitive transcranial magnetic stimulation
(rTMS), applied bilaterally over the dorsolateral prefrontal cortex (DLPFC), on cognitive function and cortical excitability
of patients with Alzheimer's disease (AD). Forty-five AD patients were randomly classified into three groups. The first two
groups received real rTMS over the DLPFC (20 and 1 Hz, respectively) while the third group received sham stimulation. All
patients received one session daily for five consecutive days. In each session, rTMS was applied first over the right DLPFC,
immediately followed by rTMS over the left DLPFC. Mini Mental State Examination (MMSE), Instrumental Daily Living Activity
(IADL) scale and the Geriatric Depression Scale (GDS) were assessed before, after the last (fifth) session, and then followed
up at 1 and 3 months. Neurophysiological evaluations included resting and active motor threshold (rMT and aMT), and the duration
of transcallosal inhibition (TI) before and after the end of the treatment sessions. At base line assessment there were no
significant differences between groups in any of the rating scales. The high frequency rTMS group improved significantly more
than the low frequency and sham groups in all rating scales (MMSE, IADL, and GDS) and at all time points after treatment.
Measures of cortical excitability immediately after the last treatment session showed that treatment with 20 Hz rTMS reduced
TI duration. These results confirm that five daily sessions of high frequency rTMS over the left and then the right DLPFC
improves cognitive function in patients with mild to moderate degree of AD. This improvement was maintained for 3 months.
High frequency rTMS may be a useful addition to therapy for the treatment of AD. 相似文献
48.
Sheikh Mohd Saleem Sheikh Imran Sayeed Khan S. Muhammad Salim Mir Shahnawaz 《International journal of diabetes in developing countries.》2019,39(2):331-339
International Journal of Diabetes in Developing Countries - Over the previous 30 years, the status of diabetes has changed from being considered as a mellow issue of the elderly to one of... 相似文献
49.
Del Fabbro Massimo Tommasato Grazia Pesce Paolo Ravidà Andrea Khijmatgar Shahnawaz Sculean Anton Galli Matthew Antonacci Donato Canullo Luigi 《Clinical oral investigations》2022,26(2):1137-1154
Clinical Oral Investigations - By means of a systematic review and network meta-analysis, this study aims to answer the following questions: (a) does the placement of a biomaterial over an... 相似文献
50.
Medulloblastoma with cartilaginous differentiation 总被引:1,自引:0,他引:1
U E Anwer T W Smith U DeGirolami H A Wilkinson 《Archives of pathology & laboratory medicine》1989,113(1):84-88
We describe the histologic, immunocytochemical, and electron microscopic features of a medulloblastoma containing cartilage that occurred in the left cerebellar hemisphere of a 57-year-old man. By light microscopy, highly cellular areas of the tumor typical of medulloblastoma showed evidence of both glial and neuroblastic differentiation. The tumor also contained foci of mature and immature cartilage. Transitions were observed between the cartilaginous foci and the more densely cellular regions of the tumor. No frankly teratomatous features or mesenchymal components other than cartilage were present. We postulate that the production of cartilage within this neoplasm most likely resulted from the metaplastic transformation of preexisting mesenchymal elements within the tumor or from multipotential neural crest-derived ectomesenchymal cells. Alternatively, the cartilage could have been produced directly by the neuroectodermal cells themselves, possibly related to a capacity for the latter to produce a chondroid ground substance. 相似文献