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排序方式: 共有1322条查询结果,搜索用时 15 毫秒
1.
Basant Pant M. D. Masayuki Sumida Kaoru Kurisu Kazunori Arita Fusao Ikawa Keisuke Migita Munenori Kutsuna Tohru Uozumi 《Neurosurgical review》1997,20(2):108-113
Thirty-eight patients with convexity lesions were studied prospectively with the two-dimensional time-of-flight (2D-TOF) magnetic resonance angiography (MRA) method. Of these 21 cases had additional surface anatomy scanning (SAS) and 7 cases had three-dimensional phase contrast (3D-PC) MRA. The findings were compared during surgery, and the predictability of 2D-TOF evaluated. 2D-TOF was obtained with 2 mm slice thickness after the administration of contrast media for routine magnetic resonance imaging (MRI). Cortical veins were visualized with a good resolution with a scan time of only 5 minutes. The tumor was also visible in the background, due to enhancement, and thus the tumor-vessels relation was shown. Slow-flow vessels were also adequately seen. SAS was done at the same sitting with fast spin echo (FSE) with a scan time of 3 minutes. Once both images were incorporated, information on gyri and their relation to the lesions and vasculature could be obtained from a single image. We found 2D-TOF alone, or at times in combination with SAS, useful for planning of operation for convexity lesions. 相似文献
2.
K Takaoka T Nishina K Ohzono M Saito M Matsui N Sugano S Saito T Kadowaki K Ono 《Clinical orthopaedics and related research》1992,(277):121-127
Eighty-three hips in 66 patients with nontraumatic avascular necrosis of the femoral head (ANFH) showing evidence of severe collapse or secondary osteoarthritic changes were treated with surgical implantation of bipolar hip prostheses either with or without cement fixation of femoral stems. The cases were observed for more than three years (range, three to ten years seven months; average, five years seven months) and assessed in terms of functional and roentgenographic results. These data were compared with the results of classic hemiarthroplasties using fixed head prostheses (Austin-Moore-type with curved or straight stem) that were performed at the authors' institutions before 1980. The results confirm that the clinical outcome is improved with use of the bipolar prosthesis. Satisfactory results (a score of 80 or greater on a hip function scoring system proposed by the Japanese Orthopaedic Association) were maintained throughout the follow-up period in most cases (71 of 83 hips) with the bipolar prosthetic replacements. In a group of patients with unsatisfactory results (12 hips), proximal migration of prosthetic head was seen in two cases. The incidence of proximal migration of bipolar heads, including those exhibiting minimal movement, was significantly lower when compared with that observed in an Austin-Moore-type head-fixed prosthesis group (7/83 versus 12/19) during a comparable postoperative follow-up period. It is noteworthy that the proximal migration of the bipolar head was not progressive, and, in most cases observed more than five years, the cartilaginous spaces of acetabulum were preserved, whereas in the Austin-Moore-replaced group, the migration was evident and progression occurred within three years of surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Sho Haneda M.D. Kouhei Fukushima M.D. Yuji Funayama M.D. Chikashi Shibata M.D. Ken-Ichi Takahashi M.D. Hitoshi Ogawa M.D. Munenori Nagao M.D. Kazuhiro Watanabe M.D. Iwao Sasaki M.D. 《Journal of gastrointestinal surgery》2006,10(7):1051-1059
Our previous studies demonstrated that sodium glucose cotransporter 1 (SGLT-1) was induced in the remnant ileum of total colectomized
rats via the action of factors other than hyperaldosteronism. The aim of the present study was to clarify whether fecal stream
is required for the enhancement of SGLT-1-mediated sodium transport. Twenty-seven pairs of ileal tissues were obtained from
the proximal and distal side, respectively, of loop ileostomy after total proctocolectomy. Mucosae were mounted in an Ussing
chamber to evaluate glucose-coupled sodium transport. Levels of SGLT-1 mRNA in proximal and distal mucosae were compared by
Northern blotting. Villous height and crypt depth were measured to test for correlations between mucosal structure and SGLT-1-mediated
sodium transport or mRNA expression levels. Both glucose-coupled sodium transport and expression of SGLT-1 mRNA were significantly
lower in distal mucosae relative to proximal mucosae. In distal mucosae, villous height, but not crypt depth, was significantly
lower than in proximal mucosae, demonstrating a positive correlation between villous height and SGLT-1 function and expression.
Comparative studies of proximal and distal mucosae demonstrated that in addition to hormonal changes, fecal stream is required
for full induction of the sodium transport system (which includes SGLT-1-mediated transport) in the remnant ileum following
total proctocolectomy.
Presented in part at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois,
May 14–19, 2005 (poster presentation).
This work was supported by Grants-in-Aid for Scientific Research 10557118 and 14657295 from the Ministry of Education, Science
and Culture of Japan to K. Fukushima, and by Kanae Foundation to K. Fukushima. 相似文献
4.
A model of hematuria was established in rabbits. An accelerated form of unilateral Masugi nephritis was induced in 10 New Zealand white rabbits by an intravenous injection of duck antirabbit kidney serum and by ligating the left renal artery immediately after the injection of the antibody. All 10 rabbits became hematuric 1-2 weeks after the injection of the antibody and red blood cell (RBC) casts were found in the urinary sediment of all these animals. An ultrastructural examination of renal glomeruli by transmission electron microscopy revealed the transcapillary passage of polymorphonuclear leukocytes through the gaps of the glomerular basement membrane (GBM). RBC were found in the urinary space in 50% of the glomeruli observed by scanning electron microscopy (SEM) and the passage of leukocytes and RBCs through the glomerular capillary wall was also observed. Gaps in the GBM became clearer after the removal of cellular components by detergents. In control rabbits, no RBCs could be observed in the urinary space, and isolated GBM were intact by SEM. These data further support the hypothesis that in rabbit Masugi nephritis hematuria is a result of the passage of RBCs through gaps in the GBM. 相似文献
5.
Sehata S Maejima T Watanabe M Ogata S Makino T Tanaka K Manabe S Takaoka M 《Toxicologic pathology》2002,30(3):328-338
The carcinogenic potential of chloroform was evaluated in a short-term carcinogenicity testing system using CB6F1 rasH2-Tg (rasH2-Tg) mice. Chloroform was administered to rasH2-Tg males at doses of 28, 90, or 140 mg/kg and rasH2-Tg females at 24, 90, or 240 mg/kg by oral gavage for 26 weeks. Wild-type (non-Tg) male and female mice received doses of 140 mg/kg and 240 mg/kg, respectively. N-methyl-N-nitrosourea was administered to rasH2-Tg mice by single intraperitoneal injection (75 mg/kg) as a positive control. In both the rasH2-Tg and non-Tg mice, there was no significant increase in the incidence of neoplastic lesions by chloroform treatment. The incidence of hepatocellular foci in the rasH2- and non-Tg females receiving 240 mg/kg was increased. Forestomach tumors and malignant tumors occurred in most of the rasH2-mice in the positive control group. Swelling or vacuolation of hepatocytes, a toxic change induced by chloroform, occurred in both the rasH2-Tg and non-Tg mice. It is concluded that chloroform, a putative human noncarcinogen, did not show evidence of carcinogenic potential in the present study using rasH2-Tg mice. This study suggests that the rasH2-Tg mouse model may not be appropriate for detecting nongenotoxic carcinogens. However, the sensitivity of rasH2-Tg mice to nongenotoxic carcinogens should be assessed with consideration of the results from the other ILSI-HESI project studies. 相似文献
6.
Komei Ito Masaki Futamura Yuri Takaoka Masashi Morishita Kumiko Nakanishi Tatsuo Sakamoto 《Arerugī》2008,57(8):1043-1052
Background: A method for open food challenge test to determine food allergy has not been established in an evidence-based manner. Methods: We conducted an analysis of 438 open food challenges of raw milk (n=133, mean age 2.7+/-1.9 years), boiled egg white (n=216, 2.8+/-2.1 years) or udon noodles (n=89, 2.7+/-1.7 years) for the patients aged 1 year or more. Doses were increased (trace amounts, 1 g, 2 g, 5 g, 10 g, 20-30 g) every 20 minutes. Results: In total, 151 (38.5%) of food challenges were positive. The positive rates of milk, egg and wheat challenges were 35.8%, 42.4% and 33.3%, respectively. Of these, 76.2%, 32.5%, 27.8% and 0.7% had, respectively, skin, respiratory, gastrointestinal and cardiovascular symptoms. Although the prevalence of positive challenge increased with level of specific IgE, it did not correlate with the threshold amount of positive food challenge or the severity of symptoms. Among the challnege positive patients, 10.6% required injection of antihistamines, corticosteroids or adrenalines for the treatment of the symptoms. Conclusions: This challenge protocol seemed to be appropriate and safe. 相似文献
7.
Regulation of the type I IFN induction: a current view 总被引:14,自引:0,他引:14
The type I IFN-alpha/beta gene family was identified about a quarter of a century ago as a prototype of many cytokine gene families, which led to the subsequent burst of studies on molecular mechanisms underlying cytokine gene expression and signaling. Although originally discovered for their activity to confer an antiviral state on cells, more evidence has recently been emerging regarding IFN-alpha/beta actions on cell growth, differentiation and many immunoregulatory activities, which are of even greater fundamental biological significance. Indeed, much attention has recently been focused on the induction and function of the IFN-alpha/beta system regulated by Toll-like receptors (TLRs), which are critical for linking the innate and adaptive immunities. The understanding of the regulatory mechanisms of IFN-alpha/beta gene induction by TLRs and viruses is an emerging theme, for which much new insight has been gained over the past few years. 相似文献
8.
Takatani T Takaoka N Tatsumi M Kawamoto H Okuno Y Morita K Masutani T Murakawa K Okamoto Y 《Molecular genetics and metabolism》2001,73(4):344-348
Reduced activity of serum lactate dehydrogenase (LDH; EC 1.1.1.27) was found in a male medical student during practical examinations of his own blood. Serum LDH isoenzyme pattern showed reductions in activities of the isoenzymes with lower subunit A/B ratios such as LDH1 and LDH2. These findings were indicative of a partial LDH-B subunit deficiency, which was confirmed in erythrocyte hemolysates by Western blotting. Polymerase chain reaction (PCR)-based DNA sequence analysis of the LDH-B subunit gene revealed a heterozygous nucleotide change: a guanine to adenine substitution in codon 69 (GGG --> GAG) at the third exon of the LDH-B subunit gene that resulted in a glycine to glutamic acid substitution (G69E). The mutation was confirmed by PCR-restriction fragment length polymorphism (RFLP) analysis using a mismatched primer to introduce a new NcoI restriction site. The same heterozygous mutation was found in his mother but not in other family members. This mutation involves a residue belonging to alphaC helix in LDH-B subunit protein molecule that functions as an interface for other subunits. 相似文献
9.
The egg dormancy and embryogenesis of the univoltine black fly, Prosimulium kiotoense Shiraki, in southwestern Japan were examined under natural and laboratory conditions. Eggs laid in April remained dormant until August (approximately 14 wk after oviposition). Hatching commenced in early October (after 23 wk), when air and water temperatures decreased to 20 and 15 degrees C, respectively, and continued until mid-December (32 wk) in the field. Laboratory experiments showed that lower temperatures (10 and 14 degrees C) supported embryogenesis similar to that observed in the field. In contrast, higher temperatures (18 and 22 degrees C) retarded or completely suppressed embryogenesis after the termination of dormancy. However, completion of dormancy was accelerated when eggs were exposed experimentally to these higher temperatures for 3-12 wk, then returned to a constant low temperature (14 degrees C). Daylength did not affect the maintenance and termination of dormancy. Therefore, temperature played an important role differentially affecting completion of dormancy and postdormancy development. Variable lengths of developmental periods among egg batches under the same conditions indicated possible genetic control of dormancy intensity. 相似文献
10.
Anterior surgery with short fusion using the Zielke procedure for thoracic scoliosis: focus on the correction of compensatory curves 总被引:3,自引:0,他引:3
Kamimura M Ebara S Kinoshita T Itoh H Nakakohji T Takaoka K Ohtsuka K 《Journal of spinal disorders》1999,12(6):451-460
Anterior instrumentation is recommended to correct idiopathic thoracolumbar or lumbar scoliosis through short fusion within the major curve. Only a few reports exist of anterior surgical correction for thoracic scoliosis. This study assessed the results of Zielke instrumentation for thoracic curve and analyzed the three-dimensional correction of deformity, especially correction of the uninstrumented compensatory curve. Seventeen patients, who had undergone selective thoracic correction and fusion using the Zielke procedure to treat thoracic scoliosis, had been followed for at least 3 years. Three-dimensional correction was evaluated radiographically. Furthermore, three-dimensional back deformities were evaluated using a topographic body scanner. Twelve patients with a single thoracic curve and five with a double curve were all female, with a mean age of 14.6 years. The preoperative main thoracic curve was 54.8 degrees +/- 10.5 degrees (range, 40-78 degrees), and it was 23.8 degrees +/- 10.5 degrees (range, 7-40 degrees) at the final follow-up examination (p < 0.0001). The average correction rate of the main curves was 56.6%. By correcting the thoracic curve, the upper and lower compensatory curves were corrected spontaneously without surgical instrumentation, with average correction rates of 45.1% and 50.2%, respectively. The average correction loss of the main curve was 2.3 degrees. The hump angle measured using a topographic body scanner decreased from 12.8 degrees +/- 4.5 degrees to 8.4 degrees +/- 4.3 degrees after surgery (p = 0.0001). Of the three patients in whom the rod broke up, only one showed a correction loss of 10 degrees; however, bony fusion was obtained. Anterior short fusion for thoracic scoliosis appears to offer significant correction, stabilization, and spontaneous correction of the compensatory lumbar curve without limiting lumbar motion. 相似文献