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141.
J. Zhao H. Sha S. Zhou X. Tong F. Y. Zhuang H. Gregersen 《Digestive and liver disease》2002,34(10):707-716
BACKGROUND: Biomechanical properties in terms of residual strains in diabetic small intestine have not been studied. Furthermore, no data have been reported on affect of gliclazide on gastrointestinal complications of diabetes. AIMS: To determine remodelling of zero-stress state of small intestine in streptozotocin-induced diabetic rats and effect of gliclazide treatment. MATERIALS: Morphological properties and residual strains were studied in duodenum, jejunum and ileum obtained from diabetic rats, gliclazide-treated diabetic rats and normal rats (n = 8 each group). METHODS: Diabetes was induced by single intraperitoneal injection of 65 mg/kg streptozotocin. Gliclazide (10 mg kg(-1) day(-1) was injected directly into stomach lumen by intragastric gavage twice daily. Experimental period was 35 days. To approach no-load state; intestinal segments were surgically excised and cut transversely into short ring-shaped segments. Each ring was cut radially to obtain geometry of zero-stress state. Circumferential length, the wall thickness and opening angle were measured from digital images of each specimen and residual strains were computed. RESULTS: Blood glucose level of diabetic group (approximately 20 mmol/l) was consistently higher than that in normal group (approximately 4 mmol/l) after induction of diabetes (p < 0.001). Gliclazide lowered average blood glucose level to between 10 and 15 mmol/l (p < 0.001). Plasma insulin levels of both diabetic groups (average between 10 and 15 pmol/l) were significantly lower than those in normal group (average approximately 18 pmol/l, p < 0.05). Wet weight per unit length and wall thickness of duodenum, jejunum and ileum were significantly higher in Diabetes group than those in Normal group (p < 0.05). Opening angle and absolute value of residual strain were significantly smaller in duodenum and larger in jejunum and ileum in Diabetes group than in Normal group (p < 0.001). Gliclazide treatment partly restored these changes (p < 0.05). CONCLUSIONS: Diabetes induced morphometric and biomechanical remodelling in intestine. Gliclazide partly restored these changes. 相似文献
142.
143.
《Respiratory investigation》2022,60(2):300-308
BackgroundIn obstructive sleep apnea (OSA), the upper airway is obstructed during sleep due to obesity and/or posterior collapse of the tongue root. Maxillofacial morphological abnormalities increase the risk of OSA in the Asian population. This study sought to elucidate whether three-dimensional (3D) photogrammetry measurements correlate with the severity of OSA irrespective of sex and degree of obesity.MethodsA prospective pilot study was performed, in which 37 consecutive adult patients (M/F = 28/9) underwent polysomnography and 3D photogrammetry in the supine position for the diagnosis of OSA. Measurements obtained from 3D photogrammetry included mandibular width (Mw), mandibular length (Ml), mandibular depth (Md), mandibular width–length angle (Mwla), and mandibular area (Ma). The effects of sex and body mass index (BMI) on the measurements and their association with the apnea–hypopnea index (AHI) were statistically analyzed. The inter-rater reliability of the measurements was evaluated using intraclass correlation coefficients (ICC).ResultsMwla (R = 0.73, p < 0.01), Mw (R = 0.39, p < 0.05), and Md (R = ?0.34, p < 0.05) were significantly correlated with the severity of OSA. On multivariate analysis, Mwla (p < 0.01) and Md (p < 0.05) remained independent factors for AHI after adjusting for sex, age, BMI, and neck circumference. In addition, diagnosability analysis revealed that Mwla was useful for identifying the presence of OSA (AHI ≥5) (cutoff: 78.6°, sensitivity: 0.938, specificity: 0.800, area under the curve: 0.931). The ICC was >0.9, showing high reliability.ConclusionsThis study suggests that Mwla measured using 3D photogrammetry can predict the presence of OSA and correlates with the severity of OSA, independent of obesity and sex. 相似文献
144.
Dual angle laser scattering cytometry (DALC) measures erythrocyte volume and haemoglobin concentration directly and provides spherocyte quantification. We have studied DALC red cell features in hereditary spherocytosis (HS) relating them to the clinical severity of the illness. A total of 140 controls and 80 non-splenectomized HS cases were studied, with mild (n = 32), moderate (n = 37) and severe (n = 11) disease. DALC measured mean corpuscular haemoglobin concentration, percentage of erythrocytes with haemoglobin concentration over 410 g/l (%Hyper), red cell volume and haemoglobin concentration distribution widths were significantly different in HS cases when compared to controls (P < 0.001). Severe HS cases had more heterogenous erythrocyte populations, both in volume and haemoglobin concentration (P < 0.001). Clinical severity of HS was best reflected by erythrocyte volume distribution width followed by %Hyper. DALC red cell features are both a diagnostic tool and an index to the severity of HS. 相似文献
145.
《Journal of biomaterials science. Polymer edition》2013,24(8):827-844
Monofilament polypropylene (PP) fibers, very similar to fibers that have been used as monofilament tailstrings of interuterinc contraceptive devices, were suspended vertically in bacterial liquid monocultures so that a portion of a fiber extended above the liquid surface. In some cases these highly oriented, cold drawn fibers were abraded prior to insertion in the cultures in order to produce surface roughness characterized by axial channels and protruding microfibrils that partially peeled from the fiber surface thereby forming the channels. Extent of migration on a fiber was assessed by aseptically cutting it into small segments, followed by culturing each segment on agar containing growth medium. Such assessment of the PP fibers after 48 h of incubation in the cultures revealed upward migration of Eschericia coli, Pseudomonas aeruginosa, and Staphylococcus aureus over significantly longer distances on the pre-roughened fibers than on those not so pre-treated. Mean measured distances of migration during 48 h were: for E. coli 2.7 ± 0.6 mm on roughened fibers (n = 16) and 0.4±0.7 mm on fibers not roughened (n = 17); for S. aureus 9.0±4.3 mm on roughened fibers (n = 13) and 0.2± 0.3 mm on fibers not roughened (n = 14); for P. aeruginosa 8.5± 3.7 mm on roughened fibers (n = 26) and 0.2± 0.5 mm on fibers not roughened (n = 5). Although no statistically significant (95% confidence level) difference could be discerned between the migration distances of S. aureus and P. aeruginosa, each of these species migrated a greater distance on the PP than did E. coli. The migrations observed are attributed predominantly to wicking of the liquid cultures upward in the axial grooves developed on the surface of the PP by the eruption and peeling of microfibrils from the surface. Surface tension of the growth medium was significantly lower than that of water and its contact angle on PP was less than 90 deg, thereby indicating a tendency to wet the PP. Bacterial growth in the medium further reduced its contact angle on PP, thereby indicating an even greater tendency to wet PP after such growth. 相似文献
146.
Maitreyee Nandi Samar Deb Jitendra Nath Pal Arunabha Tapadar Hironmoy Roy Chinmaya Kar 《Journal of the Anatomical Society of India》2013,62(1):68-72
Introduction: Quadriceps angle (Q angle) is one of the most important indicators of stability of patello-femoral joint. Orthopedic surgeons often measure the Q angle clinically in patients suffering from patello-femoral joint dysfunction or in subjects particularly young active sportspersons who are prone to injury of this joint. But the clinical method of measurement of Q angle is not standardized, and its value depends on various methods used. But the radiological method of measurement of Q angle is more accurate. However, due to the expense and time involved, the clinical method is preferred over the radiological one in practice. Aim: This study was aimed at studying the correlation and regression between the radiographic Q-angle values and the clinical ones, so that the former can be predicted easily from the latter. Materials and methods: Q angle was measured both clinically and radiographically in both knee joints of 93 adult subjects in North Bengal Medical College and Hospital. Result: Statistically significant correlation followed by the regression analysis could reveal simple linear regression equations for predicting the radiological Q-angle values from the clinical Q angle, derived separately in both males and females in right and left sides, separately. Conclusion: Thus, from a known clinical Q-angle value, we can derive the respective radiological Q angle, indirectly avoiding the entire troublesome maneuver in regular practice. So the present study recommends this method in clinical fields because this is a more rational and ideal approach to estimate the radiological Q angle. Increase in the Q angle beyond 20–22° predisposes to patellar dislocation which should be kept in mind while screening athletes, especially females. This tendency can be countered by quadriceps exercises and appropriate footwear. 相似文献
147.
《Gait & posture》2021
BackgroundRadiographic factors estimate the state of the static knee joint, and it is questionable how well these parameters reflect the dynamic knee condition. The external knee adduction moment (KAM) during gait is known to be a kinetic variable contributing to osteoarthritis progression. This study aims to investigate the effects of static radiographic parameters on the dynamic KAM during gait.MethodsOverall, 123 patients (mean age, 65.7 years; standard deviation, 8.1 years; 34 men and 89 women) were included. Seven radiographic parameters including the mechanical tibiofemoral angle (mTFA), Kellgren-Lawrence grade, and ankle joint line orientation (AJLO) were measured on radiographs, and the maximum KAM and KAM-time integral in the stance phase were obtained using three-dimensional gait analysis. The correlation and multiple regression analyses were performed for identifying significant radiographic measurements associated with the KAM.ResultsMost of the radiographic measurements correlated with the maximum KAM and KAM-time integral. As a result of multiple regression analysis, the mTFA (p < 0.001) and AJLO (p = 0.003) were identified as significant factors associated with the KAM-time integral (R2 = 0.450); the mTFA (p < 0.001) and AJLO (p = 0.003) were identified as a significant factor associated with the maximum KAM (R2 = 0.352) in multiple regression analysis. The discriminant validity of KAM was highest at varus 5.7 degree of the mTFA and 7.5 degree of the AJLO.SignificanceThe mTFA and AJLO were significantly associated with the KAM. However, to be used as a surgical indication for corrective osteotomy, a longitudinal study is needed to validate whether the mTFA and AJLO values directly cause osteoarthritis progression as we have suggested.Level of evidenceIII. 相似文献
148.
目的探讨O-arm导航辅助下后路椎弓根螺钉复位内固定治疗寰枢椎骨折的疗效。方法采用回顾性病例对照研究分析2016年1月至2018年6月河北医科大学第三医院收治的37例寰枢椎骨折患者临床资料,其中男22例,女15例;年龄29~68岁[(50.9±9.8)岁]。24例行O-arm导航辅助下后路椎弓根螺钉复位内固定术(导航组),13例行徒手后路椎弓根螺钉复位内固定术(徒手组)。比较两组手术时间和术中出血量。术前、术后7 d及末次随访采用日本骨科学会(JOA)评分和颈椎功能障碍指数(NDI)评分对患者临床疗效进行评估。观察患者并发症情况。采用Neo分级评价螺钉位置分级及皮质穿透率。结果者均获随访24~38个月[(27.7±4.0)个月]。导航组手术时间[(189.8±35.4)min]显著短于徒手组[(221.5±48.6)min](P<0.05),术中出血量[300.0(250.0,537.5)ml]〖显著少于徒手组[500.0(425.0,625.0)ml](P<0.05)。两组患者术后7 d及末次随访JOA评分较术前显著升高(P<0.05),NDI评分较术前显著降低(P<0.05)。而组间差异无统计学意义(P>0.05)。术中未见神经、血管损伤等严重相关并发症。导航组共置入椎弓根螺钉86枚,包括Neo分级0级83枚,1级2枚,2级1枚;徒手组共置入椎弓根螺钉44枚,包括Neo分级0级36枚,1级5枚,2级2枚,3级1枚(P<0.05)。导航组螺钉皮质穿透率为3%(3/86),徒手组为18%(8/44)(P<0.05)。结论对于寰枢椎骨折,在行后路椎弓根螺钉复位内固定术时,应用O-arm导航辅助可以显著缩短或减少手术时间和术中出血量,提高椎弓根螺钉置入的精确率。 相似文献
149.
Intradural petrous bone drilling has become a widespread practice, providing extended exposure in the removal of cerebellopontine angle (CPA) or petroclival tumors. Adjacent neurovascular structures are at risk, however, when drilling is performed in this deep and narrow area. Hence, this study evaluates the use of Piezosurgery (PS) as a non-rotating tool for selective bone cutting in CPA surgery.A Piezosurgery® device was used in 36 patients who underwent microsurgery for extra-axial CPA or petroclival tumors in our Neurosurgical Department between 2013 and 2019. The clinical and radiological data were retrospectively analyzed. The use of PS was evaluated with respect to the intraoperative applicability and limitations as well as efficacy and safety of the procedure.Piezosurgical petrous bone cutting was successfully performed in the removal of meningiomas or extra-axial metastases arising from the dura of the petroclival region (21 patients) or petrous bone (15 patients). PS proved to be very helpful in the deep and narrow CPA region, considerably reducing the surgeon’s distress toward bone removal in close proximity to cranial nerves and vessels in comparison to common rotating drills. The use of PS was safe without injuries to neurovascular structures. Gross total resection was achieved in 67% of petroclival and 100% of petrous bone tumors.Piezosurgery proved to be an effective and safe method for selective petrous bone cutting in CPA surgery avoiding rotating power and associated risks. This technique can particularly be recommended for bone cutting in close vicinity to critical neurovascular structures. 相似文献
150.
《Clinical neurophysiology》2021,132(4):864-871
ObjectiveWe propose a novel method that predicts facial nerve function (FNF) calculated from the drop and recovery of facial motor evoked potential (FMEP) amplitude ratio during the surgery of cerebellopontine angle tumors.MethodsWe enrolled 73 patients with cerebellopontine angle tumor, and used a biphasic, constant current, and suprathreshold stimulation (BCS) protocol to record FMEP of the orbicularis oris. We measured the intraoperative minimum-to-baseline amplitude ratio (MBR), the final-to-baseline amplitude ratio (FBR), and the recovery value (RV). RV was measured by subtracting MBR from FBR. Using those values, we evaluated FNF both at early postoperative (EP) and late postoperative (LP) periods.ResultsWe successfully obtained 62 FMEP readings. Facial palsies occurred in 22 patients during the EP period, and 14 patients recovered during the LP period. Both MBR and FBR showed a significant correlation with FNF in the EP period. RV showed a good predictive power of FNF recovery during the LP period for the first time.ConclusionsRV is a new and useful predictor of FNF recovery. MBR can be an intraoperative predictor of FNF in the EP period.SignificanceFNF outcome in the early and late postoperative periods can be predicted by FMEP. 相似文献