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排序方式: 共有6185条查询结果,搜索用时 15 毫秒
101.
K Imai T Wang R W Millard M Ashraf E G Kranias G Asano A O Grassi de Gende T Nagao R J Solaro A Schwartz 《Cardiovascular research》1983,17(11):696-709
Effects of myocardial ischaemia on sarcoplasmic reticulum (SR) of dog hearts were investigated. Regional ischaemia was produced by occlusion of the left circumflex artery, and a microsomal fraction enriched in vesicles of SR was isolated from subendocardium (Endo) and subepicardium (Epi) of control and ischaemic areas of the heart. No significant changes occurred in ischaemic Epi. A loss of in vitro activities (ie calcium transport and ATPase) was found for SR from ischaemic Endo which paralleled the changes in the histology of the tissue. At 5 min of coronary occlusion, Ca2+ binding and Ca2+-ATPase activities of SR from ischaemic Endo were normal. A decrease in the activities of SR was first evident at 15 min after the occlusion, decreased further at about 30 min and remained at that level at 60 min of ischaemia. The maximal rate of Ca2+ uptake did not parallel the Ca2+-binding and Ca2+-ATPase activities. The degree of cAMP-dependent phosphorylation by endogenous and exogenous protein kinase was not different between SR from control and ischaemic areas. A participatory role of SR in the ischaemic impairment of left ventricular systolic and diastolic performance is discussed. 相似文献
102.
103.
Lee CK Badros A Barlogie B Morris C Zangari M Fassas A van Rhee F Cottler-Fox M Jacobson J Thertulien R Muwalla F Mazher S Anaissie E Tricot G 《Experimental hematology》2003,31(1):73-80
OBJECTIVES: The aim of this study was to identify prognostic factors for outcome of high-risk patients with multiple myeloma after allogeneic transplantation prepared by reduced intensity conditioning (RIC). MATERIALS AND METHODS: Data from 45 consecutive patients (median age 52 years, range 38-68), who received grafts from a sibling (n = 34) or unrelated donor (n = 11) were analyzed. Fourteen patients received an RIC allotransplant while chemosensitive (>/=partial remission [PR]), whereas 31 chemoresistant patients (相似文献
104.
Suyog N. Jain Shahnoor R. Tamboli Dipak S. Sutar Vijay N. Mawal Ashraf A. Shaikh Ajay A. Prajapati 《Sustainable Chemistry and Pharmacy》2020
The present investigation assessed the applicability of incense stick ash, a novel and sustainable adsorbent for remediation of Victoria Blue dye from wastewater. Incense stick ash, without any physical and chemical treatment has been applied to investigate the influence of various experimental parameters as pH, loading of adsorbent, concentration, shaking time, temperature and ionic strength on Victoria Blue remediation in a batch operation. Incense stick ash was characterized using BET, DLS, SEM-EDS, FTIR and XRD techniques. BET surface area, pore volume and pore diameter of incense stick ash are obtained as 2.245 m2 g?1, 0.0118 cm3 g?1 and 21.02 nm, respectively. Average particle size of the adsorbent is obtained as 293.2 nm. Goodness of the fit of isotherm and kinetic model to the reported data was identified based on chi squared and coefficient of determination values. Isotherm and kinetic behavior was best represented by Freundlich and pseudo 2nd order equation, respectively. Boyd model confirmed involvement of film diffusion mechanism along with intra-particle for adsorption of Victoria Blue on incense stick ash. Maximum dye uptake was reported as 105.57 mg g?1. Thermodynamic study revealed spontaneous and favorable adsorption of Victoria Blue on incense stick ash at higher temperature. The performed elution and subsequent regeneration study implied desorption capability of incense stick ash and its applicability as a fresh adsorbent for further cycle of adsorption. The overall study implied scavenging potential of incense stick ash, a novel and sustainable adsorbent available at zero cost towards Victoria Blue removal. 相似文献
105.
Objective: To assess the relationship between the HLA-DRB1 genes with disease severity as assessed by radiological erosions in Malaysian patients with rheumatoid arthritis (RA).Methods: In this cross-sectional study, we studied 61 RA patients who fulfilled the ACR criteria for the diagnosis of RA. HLA-DRB1 genotyping was performed by sequence specific primer (SSP)—PCR. Radiological grading and erosive score of the hands and wrists was calculated according to the Larsen–Dale method. Demographic data and treatment given to the patients were obtained from their case records.Results: Fifty-six females and five males were studied from three ethnic groups. In 57 patients with erosions, rheumatoid factor was detected in 80%, HLA-DR4 in 40%, HLA-DRB1*0405 in 24% and shared epitope (SE) in 31%. The median delay in starting DMARDs was 24 months. The presence of rheumatoid factor, HLA-DR4 and HLA-DRB1*0405 were not significantly associated with a worse erosive score. Patients who possessed the SE had a higher erosive scores, compared to those who did not (p = 0.05). Concurrently, a delay in starting DMARD was associated with a high erosive score (p = 0.023, r = 0.348). However, after adjustment for the delay in starting DMARD, SE was no longer significantly associated with the erosive score.Conclusions: In these patients, the delay in starting DMARDs had a greater influence on the erosive score than SE alone. Whilst we cannot discount the contribution of the SE presence, we would advocate early usage of DMARDs in every RA patient to reduce joint erosions and future disability. 相似文献
106.
Hakim Hashom Mohd Khan Hussein Omar Ismail Siti Afifah Lalung Japareng Kofi Abban Edward Aziz Mohd Yusmaidie Pati Siddhartha Nelson Bryan Raveen Chambers Geoffrey Keith Edinur Hisham Atan 《International journal of legal medicine》2021,135(4):1433-1435
International Journal of Legal Medicine - DNA profiling of X-chromosomal short tandem repeats (X-STR) has exceptional value in criminal investigations, especially for complex kinship and incest... 相似文献
107.
108.
Marietta Taylor Mohd Masood George Mnatzaganian 《The Journal of prosthetic dentistry》2021,125(4):611-619
Statement of problemPatients and clinicians are aware of the efficacy and benefits of complete dentures, but evidence regarding their longevity is limited.PurposeThe purpose of this systematic review was to examine the literature describing the longevity of complete dentures and to review variations in longevity by denture type and duration of follow-up.Material and methodsFour electronic databases were searched by using key terms: MEDLINE, CINAHL (EBSCO), Dentistry and Oral Sciences Databases, and The Cochrane Library. Studies meeting the inclusion criteria were reviewed according to an established protocol and data extracted. Reference lists of identified studies were examined. Risk of bias was assessed by using the AXIS tool. Weighted means and weighted standard deviations were calculated. Pooled complete denture failure proportions were estimated by using random effects models based on the DerSimonian and Laird method.ResultsThe search yielded 21 607 unique abstracts, of which 273 met the inclusion criteria. Assessment of the full-text articles reduced this number to 42. Of these, 24 studies were rated as having low risk of bias and 18 as very low. The weighted mean ±standard deviation longevity of maxillary complete dentures was 10.3 ±3.8 years, of mandibular dentures was 8.6 ±2.6 years, and of both maxillary and mandibular dentures was 10.8 ±4.7 years. The pooled failure proportion for complete dentures observed for 2 years or less was 0.05 (95% confidence interval [CI]: 0.00-0.10), 5 to 6 years was 0.12 (95% CI: 0.08-0.16), and 10 years or more was 0.41 (95% CI: 0.28-0.53).ConclusionsComplete dentures, fabricated primarily in university settings, were found to have a weighted mean ±standard deviation longevity of 10.1 ±4.0 years. The failure rate of these prostheses increased with denture age, and the longevity of maxillary dentures was greater than that of mandibular dentures. 相似文献
109.
Rouven Schoenhof Adelheid Munz Anna Yuan Ashraf ElAyouti Hans Boesmueller Gunnar Blumenstock Siegmar Reinert Sebastian Hoefert 《Journal of cranio-maxillo-facial surgery》2021,49(6):508-517
Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive (AR) drugs such as bisphosphonates (BP) and denosumab (Dmab). Although several risk factors are described, the etiology of MRONJ is still not fully elucidated. Bone-strengthening is the primary aim of antiresorptive therapy; however, overly increased bone mass and microcrack accumulation are also discussed in MRONJ etiologies. The aim of this study is to evaluate the microarchitecture of jaw bones with micro?computed tomography (micro-CT) in AR-treated patients with or without MRONJ.Human jaw bone samples of AR-treated patients were separated into 11 groups by AR treatment bisphosphonate (BP), denosumab (Dmab), both (M) and control groups. Subgroups were divided according to the clinical localization as AR-exposed vital jaw bone (BPexp, Dmabexp, Mexp), osteonecrosis–margin of a sequestrum (BPOmar, DmabOmar, MOmar) and osteonecrosis–sequestrum (BPOseq, DmabOseq, MOseq). Healthy jaw bone (CHB) and osteoporotic jaw bone (COP) represent control groups. Samples underwent retrospective micro-CT and morphometric analysis in representative units by bone volume fraction (BV/TV), bone surface density (BS/BV), trabecular thickness (Tr.Th.), trabecular number (Tr.N.), trabecular space (Tr.Sp.), Euler characteristic for bone connectivity, bone mineral density (BMD) and tissue mineral density (TMD).A total of 141 samples from 78 patients were analyzed. BV/TV of Mexp group (mean: 0.46 ± 0.27) was significantly higher than in the COP group (mean: 0.14 ± 0.05; p = 0.0053). Tr.Th. differed significantly between the BPexp group (mean: 0.32 ± 0.15) and the Mexp group (mean: 0.57 ± 0.20; p = 0.0452) as well as between the BPOseq group (mean: 0.25 ± 0.10) and the MOseq group (mean: 0.39 ± 0.18; p = 0.0417). Signs of trabecular thickening and unorganized trabecular microarchitecture from AR-exposed- to sequestrum groups, were analyzed in 3D reconstructions. However, BS/BV, Tr.N., and Tr.Sp. showed no significant differences. Euler characteristic of the BPOseq group (median: 7.46) doubled compared to that of the BPexp group (median: 14.97; p = 0.0064). Mineralization parameters BMD and TMD were similar in all groups.Findings show evidence of enhanced bone mass and suspect microarchitecture in some AR-treated jaw bone compared to osteoporotic jaw bone. Despite increased bone mass, some MRONJ samples showed decreased trabecular connectivity by Euler characteristic compared to AR-treated jaw bone. These samples may indicate extensive ossification and ineffective bone mass with superficially higher bone mass without existing or even reduced mechanical stability, indicated by connectivity loss. This result might also suggest a high risk to microcrack accumulation. At some point, possibly some kind of over-ossification could lead to under-nourishment and microarchitectural weakness, creating instability, subsequently increasing vulnerability to MRONJ. 相似文献
110.
Wadad Sami Mneimneh Muhammad Ameen Ashraf Li Li Osama El‐Kadi Jiang Qian Tipu Nazeer Alida Hayner‐Buchan 《Pathology international》2013,63(1):68-72
Spinal primary dural lymphoma (PDL) is uncommon with a total of 37 previous well‐documented cases reported, including one diagnosed in the authors' institution. More recently we encountered an additional case of spinal PDL that, similarly to our previous case, was grade 1–2 follicular B‐cell PDL. Our two cases were diagnosed over a 3‐year interval in a 72‐year‐old female and a 74‐year‐old male, respectively. An exhaustive literature review on PDL was performed consequently to reveal that: (i) spinal and cerebral sites of involvement by PDL are constantly mutually exclusive; and (ii) unlike cerebral PDL, which is usually of marginal zone B‐cell type, only two of the 38 cases of spinal PDL were diagnosed as such, diffuse large B‐cell lymphoma being the most commonly encountered type in the spine. This divergence infers that, in contrast to the prevailing concept that PDL is a unique disease group, PDL appears to be rather heterogeneous with a difference in predilection of lymphoma type for the anatomical site of dural involvement. Such a site‐specific lymphoma‐type predilection phenomenon, well‐recognized in other organ systems, has not been acknowledged in PDL. This report brings new insights into PDL, and may contribute to a better understanding of nervous system pathophysiology and lymphoma classification. 相似文献