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981.
Fa-Hsuan Lin Shang-Yueh Tsai Ricardo Otazo Arvind Caprihan Lawrence L Wald John W Belliveau Stefan Posse 《Magnetic resonance in medicine》2007,57(2):249-257
Magnetic resonance spectroscopic imaging (MRSI) provides spatially resolved metabolite information that is invaluable for both neuroscience studies and clinical applications. However, lengthy data acquisition times, which are a result of time-consuming phase encoding, represent a major challenge for MRSI. Fast MRSI pulse sequences that use echo-planar readout gradients, such as proton echo-planar spectroscopic imaging (PEPSI), are capable of fast spectral-spatial encoding and thus enable acceleration of image acquisition times. Combining PEPSI with recent advances in parallel MRI utilizing RF coil arrays can further accelerate MRSI data acquisition. Here we investigate the feasibility of ultrafast spectroscopic imaging at high field (3T and 4T) by combining PEPSI with sensitivity-encoded (SENSE) MRI using eight-channel head coil arrays. We show that the acquisition of single-average SENSE-PEPSI data at a short TE (15 ms) can be accelerated to 32 s or less, depending on the field strength, to obtain metabolic images of choline (Cho), creatine (Cre), N-acetyl-aspartate (NAA), and J-coupled metabolites (e.g., glutamate (Glu) and inositol (Ino)) with acceptable spectral quality and localization. The experimentally measured reductions in signal-to-noise ratio (SNR) and Cramer-Rao lower bounds (CRLBs) of metabolite resonances were well explained by both the g-factor and reduced measurement times. Thus, this technology is a promising means of reducing the scan times of 3D acquisitions and time-resolved 2D measurements. 相似文献
982.
Tun Hing Lui 《Knee surgery, sports traumatology, arthroscopy》2007,15(5):671-675
We describe an arthroscopic approach of tarsometatarsal arthrodesis for post-traumatic arthritis. Five tarsometatarsal portals
(medial, P1–2, P2–3, P3–4, P4–5) are identified at the junctional points between the metatarsals by means of image intensifier.
The first metatarsocuneiform joint is approached through the medial and P1–2 portal. Articular cartilage is denuded and micro-fracture
of subchondral bone is performed with an arthroscopic awl. The second metatarsocuneiform joint is approached through the P1–2
and P2–3 portals and the third metatarsocuneiform joint is approached through the P2–3 and P3–4 portals. The articular surfaces
are prepared for arthrodesis. The articulations are kept in desired position and transfixed with 4.0 mm cannulated screws.
The fourth and fifth metatarsocuboid articulations are rarely included in the procedure. Arthroscopic arthrodesis or tendon
arthroplasty of the lateral column can be performed through the P3–4 and P4–5 portals. 相似文献
983.
Young-Mo Kim Sung-Jae Kim Jun-Young Yang Kyung-Cheon Kim 《Knee surgery, sports traumatology, arthroscopy》2007,15(7):847-850
We describe a firm, effective suture-tying method using a tensioner for reattaching tibial avulsion fractures of the anterior
cruciate ligament. Our simple method achieves strong, firm reattachment of the fracture. In addition, it prevents fixation
loosening during suture tying effectively. Since pullout repair using nonabsorbable sutures is commonly used to fix various
avulsion fractures, the tensioner helps attain strong, firm reattachment of avulsion fractures simply and effectively. 相似文献
984.
Lisbeth Brax Olofsson Olle Svensson Ronny Lorentzon Inger Lindström Håkan Alfredson 《Knee surgery, sports traumatology, arthroscopy》2007,15(5):560-563
Autologous periosteal transplantation (without chondrocyte cell transplantation) for treating traumatic articular cartilage
defects of the patella gives pain relief in uncontrolled clinical studies. To study the whole transplanted area macroscopically
and microscopically, animal studies are motivated. In this pilot study, we reproduce the surgical technique for periosteum
transplantation on human patella to a rabbit model. A full-thickness cartilage defect of the whole patella was created in
eight adult female rabbits. The defect was treated with autologous periosteal transplantation. After surgery, the rabbits
were allowed free activity. This is the difference compared to the treatment in humans, where our group uses CPM for 5 days
and non-weight-bearing for 12 weeks. After 21 weeks, there was a diffuse synovitis in all transplanted knees, and in five
of eight knees there were signs of osteoarthritis in the patello-femoral joint. Histologically, in three animals, small islands
of hyaline cartilage surrounded by fibrocartilage were seen in the transplanted area. In the other five animals, fibrocartilage
was the predominant tissue. In contrast to previous experimental studies using a rabbit model, we did not achieve hyaline
cartilage resurfacing. 相似文献
985.
Tsung-Hui Hu Jui-Wei Lin Chi-Sin Changchien Shang-Yun Liu Shue-Shian Chiou Jiin-Haur Chuang 《台湾医志》2003,102(10):707-714
BACKGROUND AND PURPOSE: Gastrointestinal stromal tumors (GISTs), identified by the presence of CD117 (KIT), were previously classified as gastric and intestinal smooth muscle tumors prior to the availability of immunohistochemical methods. This study evaluated the percentage of GISTs previously diagnosed as gastric smooth muscle tumors in our hospital during an 11-year period. METHODS: A total of 81 surgically resected gastric smooth muscle tumor specimens from 81 patients were collected from January 1986 to December 1997. Immunohistochemical studies were performed on these tumors with antibodies of CD34, CD117, smooth muscle actin (SMA), S-100, and desmin. RESULTS: Among the 81 tumors, 74 (91.4%) were CD117-positive and were classified as GISTs. Among the 74 GISTs, CD34 was positive in 72 tumors (97.3%), SMA was positive in 12 tumors (16.2%), desmin was positive in 5 tumors (6.7%), and S-100 was positive in 4 tumors (5.4%). The 7 tumors classified as non-GISTs had the following immunohistochemical characteristics: 1 was a CD117-negative CD34-positive stromal tumor (GINST) [1/81, 1.2%]; 3 were schwannomas with strong S-100-positive characteristics (3/81, 3.7%); and 3 were smooth muscle tumors with both SMA- and desmin-positive status (3/81, 3.7%). No clear relationship between CD117 or CD34 expression and prognosis was found for these tumors. CONCLUSIONS: The majority (91.4%) of gastric tumors originally diagnosed as gastric smooth muscle tumors were GISTs, except for small groups of smooth muscle tumors and schwannomas. 相似文献
986.
Dinesh Rakheja Golder N. Wilson Beverly B. Rogers 《Pediatric and developmental pathology》2003,6(3):270-277
We describe a female infant with morphologic features of Rutledge multiple-congenital-anomaly syndrome (RMCAS) and biochemical features of Smith-Lemli-Opitz syndrome (SLOS). She had microcephaly with hypoplastic cerebral frontal lobes and cerebellum, agenesis of the splenium of corpus callosum, abnormal facies including hypertelorism with bilateral inner epicanthal folds, a broad nasal bridge with slightly anteverted nares and patent choanae, low set ears and complex conchal formation, high-arched palate and thick maxillary alveolar ridges, and micrognathia. Her chest was broad, genitalia were ambiguous, and uterus was bicornuate. Skeletal abnormalities included a hypoplastic appendicular skeleton, post-axial hexadactyly of the right hand and the left foot, syndactyly of bilateral 2nd-3rd toes and left 5th-6th toes, right talipes varus and left talipes valgus, and fused L5-S1 vertebrae. Congenital heart disease consisted of hypoplastic left heart, coronary sinus agenesis, ostium secundum and ostium primum defects, and a thickened septum primum. The lungs were hypolobated and the kidneys manifested oligopapillary hypoplasia. Total colonic Hirschsprung disease was noted microscopically. Analysis of liver tissue taken at postmortem examination revealed the ratio of 7-dehydrocholesterol and cholesterol to be 143 (expected, 0.28 +/- 0.28). Although initially described as a distinct syndrome, RMCAS was merged with the severe form of SLOS, because of significantly overlapping features [Online Mendelian Inheritance in Man (OMIM) #268670]. The biochemical data showing an excess of 7-dehydrocholesterol and low cholesterol in the liver tissue of our case supports this viewpoint. 相似文献
987.
988.
Louis Pobereskin 《Acta neurochirurgica》2007,149(8):835-835
989.
Lygia Stewart J. McLeod Griffiss Gary A. Jarvis Lawrence W. Way 《Journal of gastrointestinal surgery》2007,11(8):977-984
Objective Gallstone bacteria provide a reservoir for biliary infections. Slime production facilitates adherence, whereas β-glucuronidase
and phospholipase generate colonization surface. These factors facilitate gallstone formation, but their influence on infection
severity is unknown.
Methods Two hundred ninety-two patients were studied. Gallstones, bile, and blood (as applicable) were cultured. Bacteria were tested
for β-glucuronidase/phospholipase production and quantitative slime production. Infection severity was correlated with bacterial
factors.
Results Bacteria were present in 43% of cases, 13% with bacteremia. Severe infections correlated directly with β-glucuronidase/phospholipase
(55% with vs 13% without, P < 0.0001), but inversely with slime production (55 vs 8%, slime <75 or >75, P = 0.008). Low slime production and β-glucuronidase/phospholipase production were additive: Severe infections were present
in 76% with both, but 10% with either or none (P < 0.0001). β-Glucuronidase/phospholipase production facilitated bactibilia (86% with vs 62% without, P = 0.03). Slime production was 19 (±8) vs 50 (±10) for bacteria that did or did not cause bacteremia (P = 0.004). No bacteria with slime >75 demonstrated bacteremia.
Conclusions Bacteria-laden gallstones are biofilms whose characteristics influence illness severity. Factors creating colonization surface
(β-glucuronidase/phospholipase) facilitated bacteremia and severe infections; but abundant slime production, while facilitating
colonization, inhibited detachment and cholangiovenous reflux. This shows how properties of the gallstone biofilm determine
the severity of the associated illness.
Presented at the annual meeting of the Society for Surgery of the Alimentary Tract, held May 20–24, 2006 in Los Angeles, California. 相似文献
990.
Ioannis Alexiou Anastasios Germenis Athanasios Ziogas Katerina Theodoridou Lazaros I Sakkas 《BMC musculoskeletal disorders》2007,8(1):37