bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surgical repair of spontaneous renal allograft rupture: a new procedure
Authors: He Bulang , Rao M. Mohan , Han Xiuwu , Li Xiaobei , Guan Delin , Gao Juzhong 
Published: June 2003

Background: The purpose of the present paper is to introduce a new surgical procedure using the external oblique aponeurosis (EOA) for repair of spontaneous renal allograft rupture.Methods: Thirty‐eight cases with spontaneous renal allograft rupture were encountered in 1000 consecutive kidney transplants between April 1991 and August 2000. Thirty‐three cases underwent surgical exploration with two grafts undergoing nephrectomy, while a further 31 were repaired using the new surgical procedure. The external oblique aponeurosis (EOA) from the incision was trimmed into 1 cm × 1 cm square pieces. A 2/0 Dexon suture was placed through each piece of the EOA, then through the parenchyma of the kidney perpendicular to the rupture. Each suture was then placed through another piece of EOA and tied.Results: Two repaired grafts were removed on day 7 and day 10, one due to graft re‐rupture and another with ischaemia secondary to irreversible acute rejection. The graft function of 29 cases had recovered completely at 30 days following surgical repair with one graft improving rapidly. Thirteen grafts were diagnosed as undergoing mild to moderate acute rejection, whereas a further 20 cases were considered to have acute tubular necrosis on histopathology. The allograft survival rate at 1 year and 5 years post grafting was 86% and 64%, respectively. No patients died from postoperative complications following repair using this procedure.Conclusions: Spontaneous renal allograft rupture is a relatively common post‐transplant complication secondary to either acute tubular necrosis or acute rejection. This new surgical procedure is proposed as a reliable and practical method of repair following graft rupture. Preservation of graft function and viability following rupture appears achievable both in the medium and long‐term.
Outcomes of emergency common bile duct exploration: impact of preoperative endoscopic decompression
Authors: Koh Joyce S. B. , Chow Pierce K. H. , F. Chung Alexander Y. , Ooi Lucien P. J. , Wong Wai‐Keong , Fook‐Chong Stephanie , Soo Khee‐Chee 
Published: June 2003

Background:  Emergency common bile duct exploration (CBDE) is still required in patients acutely ill with complicated biliary tract stone disease when endoscopic decompression fails to reverse their condition. This study looks at the clinical profile of patients requiring emergency CBDE and examines the various factors influencing the postoperative outcome.Methods:  Clinical records of patients with emergency CBDE in Singapore General Hospital from January 1991 to December 1998 were reviewed. Factors influencing postoperative outcomes, for example, pre‐existing medical problems, hepatic para­‐­m­eters, the impact of endoscopic procedures (if any) and indications for surgery, were correlated with postoperative morbidity and 30‐day mortality.Results:  The records of 100 patients were available for review. Major indications for emergency CBDE were cholangitis (51%) and intraoperative findings of common bile duct obstruction during emergency laparotomy (23%). Six patients had emergency CBDE because of iatrogenic complication of attempted therapeutic endoscopic retrograde cholangiopancreaticography (ERCP) for biliary stones. Overall mortality was 14.0% and 8.0% had retained stones. Mortality was significantly influenced by age, prior biliary disease, preoperative endoscopic biliary decompression in acute cholangitis (33.3%vs 9.4%, P = 0.035) and endoscopic complications.Conclusions:  Among patients requiring emergency CBDE, uncomplicated preoperative endoscopic biliary decompression ben­efits patients with acute cholangitis.
Major trauma transfer in Western Australia
Authors: Gupta Robin , Rao Sudhakar 
Published: June 2003

Background:  The transfer of critically injured patients in a rural Australian setting presents a unique challenge to medical services due to the constraints of distance and time. The purpose of this study is to analyse which injuries are being transferred, how they occur, pretransfer intervention, transfer methods and transfer times.Methods:  The Trauma Registry Database collected data prospectively on all major rural trauma cases attending the Royal Perth Hospital between August 1994 and January 2000. Patients were divided into rural and metropolitan groups on the basis of trauma location, and the latter group used as a control.Results:  A total of 1275 major trauma patients were treated of which 566 (44%) were from rural areas. Driver road traffic trauma was the most common cause of injury throughout, although most prominent in rural areas (30%vs 18%). For rural patients, the Royal Flying Doctor Service was responsible for 440 (79%) of transfers of which 83% had a doctor and a nurse escort. The most commonly transferred injuries from rural areas were head injury (63%) and thoracic injury (55%). A total of 450 (93%) rural patients were transferred to Royal Perth Hospital within 24 h of trauma although the mean transfer time was over 9 h.Conclusions:  This data produces a realistic framework of how major trauma in rural areas is treated in Western Australia. It highlights some areas of good practice, such as transfer methods and escorts, but also highlights problem areas such as transfer times and pretransfer intervention.
Single stage primary anastomosis without colonic lavage for left‐sided colonic obstruction due to acute sigmoid volvulus: a prospective study of one hundred and ninety‐seven cases
Authors: De Utpal , Ghosh Shibajyoti 
Published: June 2003

Background:  The purpose of this study was to examine the feasibility of single‐stage resection and anastomosis for acute left‐sided colonic obstruction due to acute sigmoid volvulus without intraoperative lavage. Mechanical bowel preparation has been shown to be unnecessary for elective colorectal surgery. Colonic decompression without intraoperative lavage may simplify operations in acute left‐sided colorectal obstruction.Methods:  Emergency resection of acute sigmoid volvulus was performed. This was followed by primary anastomosis without on‐table lavage after closed bowel decompression.Results:  A total of 197 patients underwent bowel decompression, resection and primary colonic anastomosis. Two patients developed anastomosis leak, requiring re‐laparotomy, Hartmann's procedure and delayed closure. Two deaths occurred postoperatively; these were unrelated to the nature of the surgery. The mean hospital stay was 9.8 days.Conclusion:  Primary colonic anastomosis can be safely done for obstructed left colon due to acute sigmoid volvulus without intraoperative colonic lavage.
Outcome after intramedullary nailing of femoral shaft fractures
Authors: Harris Ian , Hatfield Angela , Donald Geoff , Walton Judie 
Published: June 2003

Background:  The results of intramedullary nailing of femoral shaft fractures from Australian institutions have not been widely reported. This study examines a consecutive group of patients treated at a major metropolitan trauma centre and reports on the injury statistics and outcome data, and compares this to previously reported results from the literature.Methods:  A total of 101 fractures in 97 consecutive adult patients were included in the study. Nine patients were excluded. At a minimum of 6 months post injury, 54 patients were interviewed by telephone and 35 patients presented for clinical review and underwent physical examination, computed tomography (CT) scanogram of the lower limbs and Short Form 36 questionnaires.Results:  Road trauma accounted for 81% of injuries and 15% of fractures were open. Of the 54 patients reviewed, 13 (23%) required further surgery for delayed or non‐union. Of the 35 who presented for physical examination, there was poor correlation between perceived leg length discrepancy and measured leg length discrepancy on examination or scanogram. Presence of a limp correlated with measured leg length discrepancy of more than 1 cm but did not correlate with rotational abnormality measured on CT scanogram. Pain at the hip, thigh or knee was present in 60% of patients. The Short Form 36 scores for physical functioning, role − physical, bodily pain, general health and vitality were all significantly lower than population norms with P values ranging from <0.001−0.05. Subgroup analysis comparing isolated femur fracture to multi‐trauma patients for all five of these parameters revealed significant differences only in the multi‐trauma group.Conclusion:  The incidence of pain, limp, leg length discrepancy and delayed or non‐union is higher in this study than in previously reported results of intramedullary nailing for femoral shaft fractures. This may be due to differences in the patient population, the skill level of the operating surgeon, or incomplete follow up.
Impact of core biopsy on the management of screen‐detected ductal carcinoma in situ of the breast
Authors: Cheng Michael S. P. , Fox Jane , Hart Stewart A. 
Published: June 2003

Background:  Screen‐detected ductal carcinoma in situ (DCIS) usually presents as clinically impalpable microcalcification. Although core biopsy is well established as a diagnostic modality for invasive breast cancers, few reports address its impact on the management of screen‐detected DCIS. We examined the sensitivity of core biopsy in diagnosing screen‐detected DCIS, as well as its role in facilitating one‐step surgery in the community, especially a breast‐conserving approach.Methods:  Through the Monash BreastScreen database, we reviewed the management of 148 patients diagnosed with pure DCIS over a 4‐year period. Particular attention was paid to the sensitivity and surgical margin status of 63 patients who underwent initial assessment with core biopsy, compared to patients who underwent excisional biopsy or fine needle aspiration cytology (FNAC).Results:  Core specimens in 63 patients yielded positive histology in 57 (90%), allowing for breast‐conserving surgery in 45 and mastectomy in 12. Negative margins were obtained in 73% of those treated by breast‐conserving surgery, compared to 51% negative margins among those who underwent excisional biopsy initially. Overall, 45 of 57 patients with a positive core biopsy histology (79%) underwent one‐step surgery. Those assessed by FNAC had a 48% incidence of non‐diagnostic/benign cytology.Conclusions:  Core biopsy facilitates one‐step surgery for screen‐detected DCIS, and potentially reduces the number of surgical procedures. Stereotactic core biopsy for suspicious microcalcifications should replace hookwire‐guided excisional biopsy and FNAC as the diagnostic modality of choice.
Epidemiology of abdominal aortic aneurysm in an Asian population
Authors: Yii Ming Kon 
Published: June 2003

Background:  Abdominal aortic aneurysms (AAA) are common in the Caucasian population. Apart from reported differences in the occurrence of AAA in the black and white populations, there are few studies on the incidence of AAA in the Asian population.Methods:  A prospective database of all patients with AAA seen between 1996 and 1999, in the South‐East Asian state of Sarawak in Borneo Island, was analysed. The demographic data included patient's age, sex, ethnic group, date of diagnosis, comorbidities, presentations and treatment outcomes. These were compared with the state population's demographic statistics.Results:  Diagnoses of AAA were made in 123 patients during the study period. The male to female ratio was 3.5 : 1. The age range was 39−88 years with a median age of 70 years. Four patients were younger than 55 years. The incidence rate for the at‐risk male population older than 50 years was 25.6/100 000. The incidence rate reached 78.3/100 000 for males older than 70 years. The incidence rate for females older than 50 years was 7.6/100 000 and for those older than 70 years it was 18.7/100 000. All races were affected. Smoking, hypertension or respiratory disorders were present in more than 40% of the patients. Half of the patients underwent surgical repair.Conclusion:  This study shows that AAA in this Asian population is not uncommon and the incidence is comparable to the Western world.
Thrombotic complications of venous aneurysms
Authors: French James R. , Moncrieff Nicholas J. , Englund Raymond , Hanel Kevin C. 
Published: June 2003

Background:  Venous aneurysms are rare vascular anomalies that have been reported to occur throughout the body. We report a unique variation, namely a thrombosed subclavian vein aneurysm.Methods:  A review of the records of patients with documented venous aneurysms presenting to the St George Hospital and their associated imaging was made. A literature search for articles pertaining to venous aneurysms was performed.Results:  Four cases of venous aneurysms were identified; one subclavian vein, one inferior vena cava and two popliteal. The clinical course of these cases is detailed, along with a review of the literature.Conclusions:  Venous aneurysms are infrequent findings and indicate that the patient is at significant risk of thrombosis. Popliteal vein aneurysms should be treated surgically.
A fatigue damage map for 2024‐T3 aluminium alloy
Authors: RODOPOULOS C. A. , DE LOS RIOS E. R. , LEVERS A. , YATES J. R. 
Published: June 2003

ABSTRACTThe propagation of a fatigue crack from an initial defect of the same order as the scale of the microstructure through to failure has been modelled using a representation of fatigue damage according to the Navarro–de los Rios (N–R) model. The fatigue processes are presented in the form of a fatigue damage map (FDM). It is shown how the map can be used to create a traditional S–N curve and to provide information suitable for estimating fatigue lifetimes under damage tolerant conditions.
The effect of plasticity on incipient mixed‐mode fatigue crack growth
Authors: DAHLIN P. , OLSSON M. 
Published: June 2003

ABSTRACTSeveral criteria for the prediction of incipient crack path direction of non‐proportional mixed‐mode fatigue cracks, immediately after a change of load from steady mode I conditions are investigated. The analysis is based on two‐dimensional plane strain FE‐simulations in which the actual elasto‐plastic stress distribution is used for the MTS, MTSR and MEPSR criteria. The purpose of the analysis is to compare the numerical results with experimental results as well as with previous predictions based on solely elastic stress analyses, taken from the literature. It is shown that the influence from elasto‐plastic deformation on crack branching direction is of utmost importance. It is found that the incipient crack growth of metals falls into two categories: high strength metals follow the MTSp criterion whereas more ductile metals follow the MTSRp criterion. The subscript p indicates that the elasto‐plastic evaluation of the respective criterion should be used.
Inclined standing contact fatigue
Authors: ALFREDSSON B. , OLSSON M. 
Published: June 2003

ABSTRACTAn experimental method is presented, in which a sphere is repeatedly pressed against a surface with an inclined contact load. The method is a development of the normally loaded standing contact fatigue test. Experiments are performed for three inclination angles below the angle of friction and the results are compared to those of the normally loaded standing contact fatigue test. The influence of tangential load on endurance limit load, number of cycles to crack initiation, contact mark appearance and crack behaviour in the surface as well as in cut views are evaluated. The surface crack behaviour outside the contact mark is analysed based on the cyclic contact stresses in the test specimen. The trajectories of the largest principal stresses are followed in both the surface view and in the cut view on the symmetry plane. These stress trajectories are compared to the experimental crack results. The connection between the inclined standing contact fatigue cracks and surface distress micro‐cracks is also discussed.
A threshold fatigue crack closure model: Part II – experimental verification
Authors: NEWMAN J. A. , RIDDELL W. T. , PIASCIK R. S. 
Published: June 2003

ABSTRACTPredictions from an analytical model that considers contributions and interactions between plasticity, roughness, and oxide induced crack closure are presented and compared with experimental data. The analytical model is shown to correctly predict the combined influences of crack roughness, oxide debris, and plasticity in the near‐threshold regime. Furthermore, analytical results indicate closure mechanisms interact in a non‐linear manner such that the total amount of closure is not the sum of closure contributions for each mechanism.
Finite element simulation of the mechanics of flat contact pad fretting fatigue tests
Authors: HAMMOUDA M. M. I. , EL‐BATANONY I. G. , SALLAM H. E. M. 
Published: June 2003

ABSTRACTAn understanding into the macro kinetic and kinematic behaviour of fretted surfaces is provided. Making use of a modified version of a previously developed in‐house two‐dimensional elastic–plastic finite element analysis numerically simulates flat contact pad fretting fatigue tests. Basic macro mechanics concepts are adopted to idealise two bodies with rough contact surfaces and loaded at two different sites with arbitrary axial loading profiles. A time scale factor is devised to recognise the earliest candidate out of the events possibly accommodated at each loading increment.The present analysis utilises a relevant experimental set up developed in the Structural Integrity Research Institute of the University of Sheffield as an application. Computational results accurate to within 1.2% and corresponding to one contact pad span and six constant normal loads acting individually with four amplitudes of two sinusoidal axial load cycles are presented. The present computations include (1) the development of the global and local normal and tangential reactions and relative sliding displacement acting along the fretting surfaces and (2) contact pad deformation, generated stress fields and plasticity development within the neighbouring region of the fretted area.
A threshold fatigue crack closure model: Part I – model development
Authors: NEWMAN J. A. , RIDDELL W. T. , PIASCIK R. S. 
Published: June 2003

ABSTRACTA fatigue crack closure model is developed that includes the effects of, and interactions between, the three closure mechanisms most likely to occur at threshold; plasticity, roughness, and oxide. This model, herein referred to as the CROP model (for Closure, Roughness, Oxide, and Plasticity), also includes the effects of out‐of‐plane cracking and multi‐axial loading. These features make the CROP closure model uniquely suited for, but not limited to, threshold applications. Rough cracks are idealized here as two‐dimensional sawtooths, whose geometry induces mixed‐mode crack‐tip stresses. Continuum mechanics and crack‐tip dislocation concepts are combined to relate crack face displacements to crack‐tip loads. Geometric criteria are used to determine closure loads from crack‐face displacements. Finite element results, used to verify model predictions, provide critical information about the locations where crack closure occurs. The CROP model is verified with experimental data in part II of this paper.
1010‐cycle fatigue properties of 1800 MPa‐class JIS‐SUP7 spring steel
Authors: FURUYA Y. , ABE T. , MATSUOKA S. 
Published: June 2003

ABSTRACT1010‐cycle fatigue tests were conducted at 100 Hz for three years and at 20 kHz for one week on 1800 MPa‐class JIS‐SUP7 spring steel. Uniaxial tests up to 108 cycles were also conducted at 120 and 600 Hz. The 120 Hz tests had larger control volumes. The fatigue limit at 1010 cycles was lower than at 108 cycles, and any frequency effect was shown to be negligible. A size effect was found; the tests with larger control volumes showed results of lower fatigue strength.
The effect of T‐stress on plane strain dynamic crack growth in elastic–plastic materials
Authors: JAYADEVAN K. R. , NARASIMHAN R. , RAMAMURTHY T. S. , DATTAGURU B. 
Published: June 2003

ABSTRACTIn this paper, the effects of T‐stress on steady, dynamic crack growth in an elastic–plastic material are examined using a modified boundary layer formulation. The analyses are carried out under mode I, plane strain conditions by employing a special finite element procedure based on moving crack tip coordinates. The material is assumed to obey the J2 flow theory of plasticity with isotropic power law hardening. The results show that the crack opening profile as well as the opening stress at a finite distance from the tip are strongly affected by the magnitude and sign of the T‐stress at any given crack speed. Further, it is found that the fracture toughness predicted by the analyses enhances significantly with negative T‐stress for both ductile and cleavage mode of crack growth.
Deficits in spatial learning and synaptic plasticity induced by the rapid and competitive broad‐spectrum cyclooxygenase inhibitor ibuprofen are reversed by increasing endogenous brain‐derived neurotrophic factor
Authors: Shaw Kendra N. , Commins Sean , O'Mara Shane M. 
Published: June 2003

AbstractCyclooxygenase (COX), which is present in two isoforms (COX1 and 2), synthesizes prostaglandins from arachidonic acid; it plays a crucial role in inflammation in both central and peripheral tissues. Here, we describe its role in synaptic plasticity and spatial learning in vivo via an effect on brain‐derived neurotrophic factor (BDNF) and prostaglandin E2 (PGE2; both measured by Elisa). We found that broad‐spectrum COX inhibition (BSCI) inhibits the induction of long‐term potentiation (LTP; the major contemporary model of synaptic plasticity), and causes substantial and sustained deficits in spatial learning in the watermaze. Increases in BDNF and PGE2 following spatial learning and LTP were also blocked. Importantly, 4 days of prior exercise in a running wheel increased endogenous BDNF levels sufficiently to reverse the BSCI of LTP and spatial learning, and restored a parallel increase in LTP and learning‐related BDNF and PGE2. In control experiments, we found that BSCI had no effect on baseline synaptic transmission or on the nonhippocampal visible‐platform task; there was no evidence of gastric ulceration from BSCI. COX2 is inhibited by glucorticoids; there was no difference in blood corticosterone levels as measured by radioimmunoassay in any condition. Thus, COX plays a previously undescribed, permissive role in synaptic plasticity and spatial learning via a BDNF‐associated mechanism.
Intracellular calcium release resulting from mGluR1 receptor activation modulates GABAA currents in wide‐field retinal amacrine cells: a study with caffeine
Authors: Vigh Jozsef , Lasater Eric M. 
Published: June 2003

AbstractThe modulatory action of calcium (Ca2+) released from intracellular stores on GABAA receptor‐mediated current was investigated in wide‐field amacrine cells isolated from the teleost, Morone chrysops, retina. Caffeine, ryanodine or inositol 1,4,5‐triphosphate (IP3) markedly inhibited the GABAA current by elevating [Ca2+]i. The inhibition resulted from the activation of a Ca2+→ Ca2+/calmodulin → calcineurin cascade. Long (>12 s) exposure to glutamate mimicked the caffeine effect, i.e. it inhibited the GABAA current by elevating [Ca2+]i through mGluR1 receptor activation and consequent IP3 generation. This pathway provides a ‘timed’ disinhibitory mechanism to potentiate excitatory postsynaptic potentials in wide‐field amacrine cells. It occurs as a result of the suppression of GABA‐mediated conductances as a function of the duration of presynaptic excitatory input activity. This is much like some forms of long‐term potentiation in the central nervous system. In a local retinal circuit this will selectively accentuate particular excitatory inputs to the wide‐field amacrine cell. Similar to other neural systems, we suggest that activity‐dependent postsynaptic disinhibition is an important feature of the signal processing in the inner retina.