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51.
In the guinea-pig tracheal smooth muscle, effects of various relaxants were compared in normal (5.9 mM) and excess (40 mM) K media. The relaxing effect of calcium-channel blockers, nifedipine and verapamil (group I) was potentiated by increasing the external K concentration. The effect of the drugs which are supposed to increase intracellular cyclic AMP, such as isoprenaline, forskolin, isobutylmethylxanthine, theophylline, dibutyryl cyclic AMP (group II) was moderately reduced by excess K. Nitroprusside, 8-bromo-cyclic GMP and sodium nitrite (group III) are generally considered to increase intracellular cyclic GMP and their effect was markedly reduced by excess K. When the tension development was made the same at 5.9 mM K and 40 mM K by adjusting the Ca concentration, the relaxing effect was similar and independent of the K concentration both for group II and group III drugs. It seems that the group II drugs can better overcome a large influx of Ca than group III drugs.  相似文献   
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Full length cDNA and gene encoding ghrelin precursor and mature ghrelin peptide were identified from the stomach of Pacific bluefin tuna, Thunnus orientalis, which has unique metabolic physiology and high commercial value at fishery markets. Quantitative expression analysis was conducted for the gastric ghrelin and pepsinogen 2 genes during the early stage of somatic growth from the underyearling to yearling fish. The full length cDNA of bluefin tuna ghrelin precursor has a length of 470bp and the deduced precursor is composed of 107 amino acids. The ghrelin gene is 1.9kbp in length and has a 4 exon-3 intron structure. The major form of mature ghrelin in the stomach was an octanoylated 20-amino acid peptide with C-terminal amidation, while overall 12 different forms of ghrelin peptides, including short form of 18-amino acid peptide and seven kinds of acyl modifications were identified. The expression profiles of the gastric ghrelin and pepsinogen 2 genes showed no significant changes related to the early growth stages. The present results suggest that digestive physiology has already been functional in this growth stage of the juvenile bluefin tuna and ghrelin may have a role in the sustained digestive and metabolic activities.  相似文献   
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The aim of this study was to measure exercise-induced changes in knee joint laxity in patients with knee osteoarthritis (OA). The study subjects were 46 female patients with OA and 22 age- and sex-matched normal controls. Radiographs of the knee were taken in all subjects, and the disease severity was graded according to the Kellgren and Lawrence (K-L) grading system. The K-L grade of the control subjects (non-OA group) was 0-1. The OA patients were divided into those with mild OA (K-L grade 2, n = 20) and advanced OA (K-L grade 3-4, n = 26). The subject climbed up and down 8 steps on a staircase apparatus over a period of 10 min. The anteroposterior (A-P) translation was measured with KT2000 arthrometer, and varus-valgus (V-V) rotation was measured on stress radiographs before and after the stair climbing. The Δchange in A-P translation after the exercise was significantly larger in mild OA group than other groups (P < 0.005). The Δchange in V-V rotation after exercise was significantly larger in mild and advanced OA groups than the control (P < 0.003). There were no significant differences in A-P laxity and V-V laxity before exercise among the non-OA, mild OA and advanced OA groups. Exercise resulted in significant changes in A-P knee joint laxity in patients with mild OA relative to the control. The results suggest that daily physical activities (e.g., knee bending or squatting) play a role in the development of knee laxity, particularly in patients with mild OA, and that progression of knee OA seems to correlate with increments of A-P knee joint laxity.  相似文献   
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Purpose

Diabetes mellitus (DM) is known as an important risk factor for surgical site infection (SSI) in spine surgery. It is still unclear however which DM-related parameters have stronger influence on SSI. The purpose of this study is to determine predisposing factors for SSI following spinal instrumentation surgery for patients with DM.

Methods

110 DM patients (66 males and 44 females) who underwent spinal instrumentation surgery in one institute were enrolled in this study. For each patient, various preoperative or intraoperative parameters were reviewed from medical records. Patients were divided into two groups (SSI or non-SSI) based on the postoperative course. Each parameter between these two groups was compared. Univariate and multivariate analyses were performed to determine predisposing factor for SSI.

Results

The SSI group consisted of 11 patients (10 %), and the non-SSI group of 99 patients (90 %). Univariate analysis revealed that preoperative proteinuria (p = 0.01), operation time (p = 0.04) and estimated blood loss (p = 0.02) were significantly higher in the SSI group compared to the non-SSI group. Multivariate logistic regression identified preoperative proteinuria as a statistically significant predictor of SSI (OR 6.28, 95 % CI 1.58–25.0, p = 0.009).

Conclusions

Proteinuria is a significant predisposing factor for SSI in spinal instrumentation surgery for DM patients. DM patients with proteinuria who are likely to suffer latent nephropathy have a potential risk for SSI. For them less invasive surgery is recommended for spinal instrumentation. In this retrospective study, there was no significant difference of preoperative condition in glycemic control between the two groups.  相似文献   
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This report describes case series of the femoral head fractures associated with fracture-dislocation of the hip joint to evaluate the mid- and long-term outcomes and to highlight the surgical technique of fixation of the femoral head from the posterior trochanteric flip osteotomy approach. Twelve patients (6 men and 6 women) with dislocated femoral head fractures (mean age at the time of injury, 56 years; range, 23–80) were followed up for mean period of 9.7 years (range, 5–20). All dislocations were reduced within less than 6 h after the injury. The type of femoral head fracture was classified according to the Pipkin classification on radiographs and CT. Five patients were classified as type I, 2 as type II, 2 as type III, and 3 as type IV. The clinical and radiological outcomes were assessed by Thompson and Epstein’s regimen. Excluding 2 patients with Pipkin type III, the outcome of 9 patients was excellent/good, and poor in 1. The latter patient sustained Pipkin type IV and developed osteoarthritis 1 year after surgery and consequently required total hip arthroplasty. We conclude that small fragment of the femoral head less than 1 cm can be removed, while larger fragments should be fixed by bioabsorbable screws or pins in all types of femoral head fractures. In Pipkin type IV fractures, surgeons should always take anatomical reduction in the acetabulum into consideration during surgery.  相似文献   
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