414 research outputs found
Posterior Surgery for Cervical Myelopathy: Laminectomy, Laminectomy with Fusion, and Laminoplasty
Surgical Treatment for Skeletal Metastases From Soft Tissue Sarcomas: Experience With 23 Lesions in 20 Patients
Purpose. This paper reports the procedures and the clinical results of a series of surgical treatments for skeletal metastases from soft tissue sarcomas
Late Holocene volcanic activity and environmental change in Highland Guatemala
We present a record of late Holocene volcanic eruptions with elemental data for a sequence of sampled tephras from Lake Amatitlan in Highland Guatemala. Our tephrochronology is anchored by a Bayesian P_Sequence age-depth model based on multiple AMS radiocarbon dates. We compare our record against a previously published study from the same area to understand the record of volcanism and environmental changes. This work has implications for understanding the effects of climate and other environmental changes that may be related to the emission of volcanic aerosols at local, regional and global scales
Prediction of myelopathic level in cervical spondylotic myelopathy using diffusion tensor imaging
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Magnetic properties of surficial sediments in Lake Ogawara on the Pacific coast of northeastern Japan: spatial variability and correlation with brackish water stratification
To examine limnological conditions in Lake Ogawara on the Pacific coast of northwestern Japan, we investigated the magnetic properties of dredged bottom sediment originally collected from the lake in the summer of 2011. We used non-destructive methods to measure the low-field magnetic susceptibility shortl after sampling, and anhysteretic remanent magnetization (ARM) was assessed in 2012 and 2015. The ARM acquisition and demagnetization curves from littoral sites showed several patterns that reflect the provenance of the sediments. At water depths below 10 m, the magnetic susceptibility and ARM of greenish black mud with high organic content decreased considerably with the increase in water depth, but ARM increased slightly at water depths greater than 16 m. We also found that the magnetic concentrations of mud samples were reduced markedly during a period of storage for about 3 years. We attributed these reductions to diagenetic loss of magnetic minerals, which had been enhanced at deeper sites. It is possible that the ARM carriers in deeper areas were derived from authigenic formation of iron sulfide or from deposition of suspended matter in the hypolimnion water. We propose that the magnetic properties of surficial sediments are controlled by limnological stratification of the brackish lake water, thus possibly providing an analog for down-core variations of magnetic parameters associated with the modification of magnetic minerals during reductive diagenesis
Successful outcome of six-level cervicothoracic corpectomy and circumferential reconstruction: case report and review of literature on multilevel cervicothoracic corpectomy
The authors report the successful outcome of a six-level corpectomy across the cervico-thoracic spine with circumferential reconstruction in a patient with extensive osteomyelitis of the cervical and upper thoracic spine. To the authors’ knowledge, this is the first report of a corpectomy extending across six levels of the cervico-thoracic spine. Clinical relevance: the authors recommend anterior cage and plate-assisted reconstruction and additional posterior instrumentation using modern spinal surgical techniques and implants
Reconstruction of northeast Asia spring temperature 1784–1990
We describe a first attempt of wide-area dendroclimatic reconstruction, based upon seven spring temperaturesensitive chronologies from the ring widths of living trees, in Japan and Korea. Mean March–May temperature derived from a gridded land air temperature dataset (CRUTEM4) between 35–40; N and 125–140; E was reconstructed for the period of AD1784–1990. Of the seven, two Japanese chronologies were eliminated during the calibration trials. The reconstruction accounted for 19.4% of the temperature variance in the calibration period, and is considered to be skillful for estimating interannual-to-interdecadal variations and not for long-term change. This reconstruction showed remarkably similar fluctuations to regional dendroclimatic reconstructions in Japan and Korea, indicating the past spatial coherency of spring temperatures in the region. The reconstruction was validated against other climate proxies. A fairly good agreement was found with cold periods as estimated from documentary records in southeast China and Japan. The west Japan temperature series recovered from instrumental records also showed a reasonable agreement with the reconstruction. On the other hand, the reconstruction did not show clear abrupt depressions after the Laki and the Tambora eruptions. These comparisons revealed that dendroclimatic spatial reconstruction in this area offers a good potential for reconstructing long-term and large-scale past temperature patterns for northeast Asia
Postoperative Spinal Epidural Hematoma: Risk Factor and Clinical Outcome
We report a series of epidural hematomas which cause neurologic deterioration after spinal surgery, and have taken risk factors and prognostic factors into consideration. We retrospectively reviewed the database of 3720 cases of spine operation in a single institute over 7 years (1998 April-2005 July). Nine patients who demonstrated neurologic deterioration after surgery and required surgical decompression were identified. Factors postulated to increase the postoperative epidural hematoma and to improve neurologic outcome were investigated. The incidence of postoperative epidural hematoma was 0.24%. Operation sites were cervical 3 cases, thoracic 2 cases, and lumbar 4 cases. Their original diagnoses were tumor 3 cases, cervical stenosis 2 cases, lumbar stenosis 3 cases and herniated lumbar disc 1case. The symptoms of epidural hematomas were neurologic deterioration and pain. After decompression, clinical outcome revealed complete recovery in 3 cases (33.3%), incomplete recovery in 5 cases (55.6%) and no change in 1 case (11.1%). Factors increasing the risk of postoperative epidural hematoma were coagulopathy from medical illness or anticoagulation therapy (4 cases, 44.4%) and highly vascularized tumor (3 cases, 33.3%). The time interval to evacuation of complete recovery group (29.3 hours) was shorter than incomplete recovery group (66.3 hours). Patients with coagulopathy and highly vascularized tumor were more vulnerable to spinal epidural hematoma. The postoperative outcome was related to the preoperative neurological deficit and the time interval to the decompression
New 14C Determinations from Lake Suigetsu, Japan:12,000 to 0 Cal BP
Calibration is a fundamental stage of the radiocarbon (14C) dating process if one is to derive meaningful calendar ages from samples’ 14C measurements. For the first time, the IntCal09 calibration curve (Reimer et al. 2009) provided an internationally ratified calibration data set across almost the complete range (0 to 50,000 cal BP) of the 14C timescale. However, only the last 12,550 cal yr of this record are composed of terrestrial data, leaving approximately three quarters of the 14C timescale necessarily calibrated via less secure, marine records (incorporating assumptions pertaining to the temporally variable “marine reservoir effect”). The predominantly annually laminated (varved) sediment profile of Lake Suigetsu, central Japan, offers an ideal opportunity to derive an extended terrestrial record of atmospheric 14C across the entire range of the method, through pairing of 14C measurements of terrestrial plant macrofossil samples (extracted from the sediment) with the independent chronology provided through counting of its annual laminations.
This paper presents new data (182 14C determinations) from the upper (largely non-varved) 15 m of the Lake Suigetsu (SG06) sediment strata. These measurements provide evidence of excellent coherence between the Suigetsu 14C data and the IntCal09 calibration curve across the last ~12,000 cal yr (i.e. the portion of IntCal based entirely on terrestrial data). Such agreement demonstrates that terrestrial plant material picked from the Lake Suigetsu sediment provides a reliable archive of atmospheric 14C, and therefore supports the site as being capable of providing a high-resolution extension to the “wholly terrestrial” (i.e. non-reservoir-corrected) calibration curve beyond its present 12,550 cal BP limit
JOA Back Pain Evaluation Questionnaire: initial report
AbstractBackgroundThere is no widely accepted objective evaluation for lumbar spine disorders. New outcome measures should be patient-oriented and should measure symptoms and self-reported functional status in multiple dimensions. The aim of this study was to identify items to be included in the disease-specific quality of life (QOL) questionnaire for the assessments of patients with lumbar spine disorders.MethodsThe draft of the QOL questionnaire that consisted of a total of 60 items, including 24 items derived from the Japanese version of the Roland Morris Disability Questionnaire (RDQ) and 36 items derived from the Japanese version of Short Form 36 (SF-36), were administered to patients and controls. After obtaining written informed consent, the following data were collected from the patient group (n = 328) and the control group (n = 213): (1) background characteristics, including age, diagnosis, Japanese Orthopaedic Association (JOA) score, and finger to floor distance; (2) responses to the questionnaire; (3) the identification rate by discrimination analysis to select the candidates for adoption and by adopting explanatory variables. The items to be excluded were determined by examining the explanatory variables, which were selected after the discrimination analysis, by setting the candidate to-be-excluded items as an objective variable.ResultsBased on the distribution of the responses, two items, RDQ-15 and RDQ-19, were excluded. From the results of the correlation coefficient calculation for each question in the patient group, 33 items were excluded and 27 candidate items were adopted. Based on the adoption explanatory variable used in the discrimination analysis, 25 of the 27 candidate items for adoption were accepted.ConclusionsThis study identified the 25 specific questionnaire items that should be included in the questionnaire to evaluate QOL of patients with various lumbar spine disorders
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