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71.
Brian W. MacLaughlinDavid S. Plurad M.D. William SheppardScott Bricker M.D. Fred BongardAngela Neville M.D. Jennifer A. SmithBrant Putnam M.D. Dennis Y. Kim 《American journal of surgery》2015,210(6):1082-1087
Background
The effect of intracranial pressure (ICP) monitoring on mortality after severe traumatic brain injury (sTBI) remains unclear. We hypothesized that ICP monitoring would not be associated with improved survival in patients with sTBI.Methods
A retrospective analysis was performed on sTBI patients, defined as admission Glasgow Coma Scale score of 8 or less with intracranial hemorrhage. Patients who underwent ICP monitoring were compared with patients who did not. The primary outcome measure was inhospital mortality.Results
Of 123 sTBI patients meeting inclusion criteria, 40 (32.5%) underwent ICP monitoring. On bivariate and multivariate regression analyses, ICP monitoring was associated with decreased mortality (odds ratio = .32, 95% confidence interval = .10 to .99, P = .049). This finding persisted on propensity-adjusted analysis.Conclusions
ICP monitoring is associated with improved survival in adult patients with sTBI. In addition, significant variability exists in the use of ICP monitoring among patients with sTBI. 相似文献72.
Renu Sharma Aditya N Aggarwal Shuchi Bhatt Sudhir Kumar SK Bhargava 《Indian Journal of Orthopaedics》2015,49(5):542-548
Background:
de Quervain''s tenosynovitis is an inflammation of abductor pollicis longus (APL) and extensor pollicis brevis (EPB) muscle tendon sheaths at the level of radial styloid process. Its conservative management includes nonsteroidal anti-inflammatory drugs, wrist and thumb immobilization, ultrasonic therapy (US Th.) and low level laser therapy (LLLT). Literature is scanty on comparative efficacy of US Th. and LLLT for its management. This prospective study evaluates outcome of US Th. versus LLLT in de Quervain''s disease.Materials and Methods:
Thirty patients clinically diagnosed de Quervains tenosynovitis were included in the study and randomly assigned to two groups. The average age was 36 years (range: 21-45 years). One group was given LLLT and the other US Th. for a total of 7 exposures on alternate days. The clinical criteria used were Finkelstein''s test, tenderness over radial styloid (Ritchie''s tenderness scale), grip strength, pain (visual analog scale [VAS]) and radiological criteria was ultrasonographic assessment of change in thickness of APL and EPB tendon sheath. They were measured before commencement and at the end of seven sessions of therapy, as per standard procedure.Results:
Significant improvement was seen within both groups in the following outcome measures assessed: Ritchie''s tenderness scale, grip strength and VAS. Finkelstein''s test was not significantly improved in either groups. Ultrasonographic measurement of tendon sheath diameters, the mediolateral (ML), and anteroposterior (AP) diameters was not found to be significantly different in the US Th. group and the laser therapy group after treatment. On comparing both the groups, no statistically significant difference was found. However, looking at the mean values, the grip strength and VAS showed better improvement in the US Th. group as compared to the laser therapy group. 相似文献73.
Nemandra Sandiford SK Muirhead-Allwood JA Skinner 《Indian Journal of Orthopaedics》2015,49(6):595-601
Background:
Hip resurfacing arthroplasty (HRA) is primarily indicated for young, active patients with disabling coxarthrosis who wish to remain active and return to sports after surgery. Relatively few prospective studies have assessed return to sporting activity and impact of gender and age on this.Materials and Methods:
Seventy-nine consecutive patients treated with HRA were included. Patients were reviewed clinically and radiologically. Function was assessed using the modified University of California Los Angeles (UCLA) activity score. The Oxford, Harris and WOMAC hip scores were calculated.Results:
Average age at the time of surgery was 54.9 years (range 34.5–73.6 years). Average preoperative and postoperative UCLA scores were 4 and 7.6 respectively. Patients were involved in 2 (0–4) sporting activities preoperatively and 2 (0–5) postoperatively. Preoperative and postoperative Oxford Hip Scores, Harris Hip Score and WOMAC scores were 40, 46 and 51 and 16, 94 and 3 respectively (P < 0.0001). Patients returned to sports at an average of 3 months postoperatively.Conclusion:
Patients were able to return to sports by 3 months and perform the same number of activities at preoperative intensity. Activity levels are maintained up to the medium term with few complications. 相似文献74.
Expression and function of CD40 on Hodgkin and Reed-Sternberg cells and the possible relevance for Hodgkin's disease 总被引:7,自引:2,他引:7
Gruss HJ; Hirschstein D; Wright B; Ulrich D; Caligiuri MA; Barcos M; Strockbine L; Armitage RJ; Dower SK 《Blood》1994,84(7):2305-2314
CD40 was originally described as a B-cell-restricted antigen and was subsequently found to be a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 is also expressed on dendritic cells, thymic epithelium, monocytes, and some carcinoma cell lines, and plays a critical role in cell contact-dependent activation. Primary and cultured Hodgkin and Reed-Sternberg (H-RS) cells, the presumed malignant cells of Hodgkin's disease (HD); were found to express high levels of cell surface CD40. We found that recombinant CD40 ligand (CD40L) induced interleukin-8 (IL-8) secretion and enhanced IL-6, TNF, and lymphotoxin-alpha (LT-alpha/TNF-beta) release from cultured H-RS cells. These cytokines play a significant role in the clinical presentation and pathology of HD, a tumor of cytokine-producing cells. CD40L had no mitogenic activity for HD-derived cell lines. In contrast, CD40L enhanced expression of costimulatory molecules intracellular adhesion molecule-T and B7-1 on cultured H-RS cells, both of which are overexpressed on primary H-RS cells. In addition, CD40L induced a 40% to 60% reduction of the expression of the HD-associated CD30 antigen, another member of the TNF receptor superfamily. Primary and cultured H- RS cells express not only CD30, but also CD40. CD40L has pleiotropic biologic activities on H-RS cells, and the CD40-CD40L interaction might be a critical element in the deregulated cytokine network and cell contact-dependent activation cascade typical for HD. 相似文献
75.
Amino acid sequence of the variable region of a human mu chain: location of a possible JH segment.
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D W Lehman F W Putnam 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(6):3239-3243
The complete amino acid sequence of th variable (V) region of the mu heavy chain of a human IgM immunoglobulin (Cam) has been determined. The strategy for sequence determination involved sequenator analysis of the CNBr cleavage products of the succinylated carboxymethylated Fab mu fragment, and of tryptic peptides of the CNBr polypeptides and thermolytic subpeptides. The variable region of this heavy chain (VH) belongs to the VHIII subgroup; it has greater than 70% homology with other VHIII sequences and contains the VHIII marker peptide, Phe-Thr-Ile-Ser-Arg (residues 67-71). As more sequences have been published, the number of subgroup-specific residues has diminished to the point that no position is absolutely subgroup specific. An analysis of the available human VH sequences in the V/C switch region showed the likelihood of a human JH segment (residues 101-113) analogous to the J segments in mouse light chains. The JH region is highly conserved, has striking homology to proposed mouse JH regions, and has significant homology to known mouse J lambda and J kappa segments. 相似文献
76.
Biological evaluation of intervertebral disc cells in different formulations of gellan gum‐based hydrogels
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G Khang SK Lee HN Kim J Silva‐Correia ME Gomes CAA Viegas IR Dias JM Oliveira RL Reis 《Journal of tissue engineering and regenerative medicine》2015,9(3):265-275
Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
77.
78.
Identical structural changes in inherited albumin variants from different populations. 总被引:2,自引:6,他引:2
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K Arai N Ishioka K Huss J Madison F W Putnam 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(2):434-438
Alloalbuminemia is rare and has a cumulative frequency of only approximately 1 in 3,000 in Europeans and Japanese. The worldwide ethnic and geographic distribution of certain albumin genetic variants appears to be nonrandom. Moreover, we have found that structurally identical variants may occur at different frequencies in ethnically distinct populations, presumably owing to independent mutations. In this study, albumin B and two types of proalbumins, which as a group are the most common European albumin variants, have also been found in Asians. We have identified the amino acid substitution characteristic of albumin B (glutamic acid----lysine at position 570) in alloalbumins from six unrelated individuals of five different European descents and also in two Japanese and one Cambodian. The two types of proalbumins most common in Europe (Lille type, arginine----histidine at position -2; Christchurch type, arginine----glutamic acid at position -1) also occur in Japan. These results provide evidence for independent mutations at single sites in the albumin genome. The clustering of these and of several other amino acid exchanges in certain regions of the albumin molecule suggests two possibilities: that certain sites are hypermutable or that mutants involving certain sites are more subject to selection than mutants involving others. 相似文献
79.