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61.
We have determined the consequences of insulin-like growth factor-binding protein-1 (IGFBP-1) administration alone and in combination with insulin-like growth factor-I (IGF-I). Human recombinant IGF-I, infused as a bolus into male Wistar rats, induced a fall in plasma glucose to 72 +/- 3% of baseline 15 min after injection. Co-infusion of equimolar concentrations of human IGFBP-1 abolished the IGF-I-induced fall (P less than 0.001). Injection of IGFBP-1 alone caused a rise in plasma glucose levels (P less than 0.002). The half life of human IGFBP-1, measured using a primate-specific RIA, was 12.5 +/- 0.7 min and was not influenced by the co-infusion of IGF-I. This study demonstrates that, in the rat, human IGFBP-1 blocks the hypoglycemic response to intravenous IGF-I and increases blood glucose levels when administered alone. Since IGFBP-1 concentrations are dependent on metabolic status, we suggest that fluctuating IGFBP-1 levels might modulate the hypoglycemic activity of unbound IGFs in the circulation. 相似文献
62.
Vishnu Prasad Pulappadi Smita Manchanda Pritviraj SK Smriti Hari 《The British journal of radiology》2021,94(1117)
Corpus luteum rupture presenting as acute abdomen is an underdiagnosed condition. Though a self-limiting entity, its differentiation from other causes is essential to prevent unnecessary surgical procedures. The radiologist should be aware of the possibility of a ruptured haemorrhagic ovarian cyst in a female of reproductive age group presenting with pelvic pain and a large amount of haemorrhagic ascites. Imaging characteristically reveals a thick-walled cystic structure in the adnexa with internal echoes, focal discontinuity or irregularity of its wall with haemoperitoneum. While sonography is usually indicative of corpus luteum rupture, cross-sectional imaging (CT/MRI) can be used to confirm the diagnosis. 相似文献
63.
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64.
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65.
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
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69.
Bradley Jacobson Michael Cendoma Jacob Gdovin Kevin Cooney Dustin Bruening 《Journal of Athletic Training》2014,49(1):42-48
Context
The National Athletic Trainers'' Association position statement on acute management of the cervical spine-injured athlete recommended the all-or-nothing endeavor, which involves removing or not removing both helmet and shoulder pads, from equipment-laden American football and ice hockey athletes. However, in supporting research, investigators have not considered alternative protocols.Objective
To measure cervical spine movement (head relative to sternum) produced when certified athletic trainers (ATs) use the all-or-nothing endeavor and to compare these findings with the movement produced using an alternative pack-and-fill protocol, which involves packing the area under and around the cervical neck and head with rolled towels.Design
Crossover study.Setting
Movement analysis laboratory.Patients or Other Participants
Eight male collegiate football players (age = 21.4 ± 1.4 years; height = 1.87 ± 0.02 m; mass = 103.6 ± 12.5 kg).Intervention(s)
Four ATs removed equipment under 4 conditions: removal of helmet only followed by placing the head on the ground (H), removal of the helmet only followed by pack-and-fill (HP), removal of the helmet and shoulder pads followed by placing the head on the ground (HS), and removal of the helmet and shoulder pads followed by pack-and-fill (HSP). Motion capture was used to track the movement of the head with respect to the sternum during equipment removal.Main Outcome Measure(s)
We measured head movement relative to sternum movement (translations and rotations). We used 4 × 4 analyses of variance with repeated measures to compare discrete motion variables (changes in position and total excursions) among protocols and ATs.Results
Protocol HP resulted in a 0.1 ± 0.6 cm rise in head position compared with a 1.4 ± 0.3 cm drop with protocol HS (P < .001). Protocol HP produced 4.9° less total angular excursion (P < .001) and 2.1 cm less total vertical excursion (P < .001) than protocol HS.Conclusions
The pack-and-fill protocol was more effective than shoulder pad removal in minimizing cervical spine movement throughout the equipment-removal process. This study provides evidence for including the pack-and-fill protocol in future treatment recommendations when helmet removal is necessary for on-field care.Key Words: National Athletic Trainers'' Association position statement, pack and fill, motion analysis, helmet removalKey Points
- The pack-and-fill protocol resulted in less overall motion than removal of the helmet and shoulder pads followed by placing the head on the ground, which is currently endorsed by the National Athletic Trainers'' Association.
- Using pack and fill, the athletic trainers could position the head at release in, on average, nearly the identical position as at initiation.
- Removal of the helmet and shoulder pads resulted in a drop in linear and angular head position, placing the cervical spine into increased extension.
70.
L Blanc SL Ciciotte B Gwynn GJ Hildick-Smith EL Pierce KA Soltis JD Cooney BH Paw LL Peters 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(30):12099-12104
Phenotype-driven approaches to gene discovery using inbred mice have been instrumental in identifying genetic determinants of inherited blood dyscrasias. The recessive mutant scat (severe combined anemia and thrombocytopenia) alternates between crisis and remission episodes, indicating an aberrant regulatory feedback mechanism common to erythrocyte and platelet formation. Here, we identify a missense mutation (G125V) in the scat Rasa3 gene, encoding a Ras GTPase activating protein (RasGAP), and elucidate the mechanism producing crisis episodes. The mutation causes mislocalization of RASA3 to the cytosol in scat red cells where it is inactive, leading to increased GTP-bound Ras. Erythropoiesis is severely blocked in scat crisis mice, and ~94% succumb during the second crisis (~30 d of age) from catastrophic hematopoietic failure in the spleen and bone marrow. Megakaryopoiesis is also defective during crisis. Notably, the scat phenotype is recapitulated in zebrafish when rasa3 is silenced. These results highlight a critical, conserved, and nonredundant role for RASA3 in vertebrate hematopoiesis. 相似文献