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排序方式: 共有5012条查询结果,搜索用时 15 毫秒
21.
Hironobu Fukuzaki Yoshikazu Aiba Masaru Yoshida Masaharu Asano Minoru Kumakura 《Macromolecular chemistry and physics.》1989,190(10):2571-2577
Biodegradable copolymers of L -lactic acid (L -LA) and DL -α-hydroxy acids with relatively low molecular weights, for example L -LA/DL -lactic acid (DL -LA), L -LA/DL -α-hydroxybutyric acid (DL -HBA), L -LA/DL -α-hydroxyisovaleric acid (DL -HIVA), and L -LA/DL -α-hydroxyisocaproic acid (DL -HICA), were synthesized by quantitative direct copolycondensation without catalysts at 200°C. The in vitro degradation, which was evaluated by measuring the weight loss of these copolymers in M/15 phosphate buffer solution (pH 7,2) without enzymes at 37°C, is strongly dependent on the kind and molecular weight of these copolymers, resulting in the formation of different degradation patterns such as parabola type (L -LA/DL -HBA system), linear type (L -LA/DL -LA system), and S type (L -LA/DL -HIVA and L -LA/DL -HICA systems). 相似文献
22.
Crystal-matrix interrelations in brushite and uric acid calculi 总被引:1,自引:0,他引:1
Brushite and uric acid calculi were studied by means of scanning electron microscopy with the partial dissolution method and transmission electron microscopy. Brushite calculi consist of radially oriented columnar crystals which have sheet-like substructure. The organic matrix is identified chiefly at the outside of the crystals but partly included between the substructure. The concentric matrix bands are often dislocated between the neighbouring crystals. Uric acid calculi also consist of radially oriented columnar crystals, and a fine meshwork of the organic matrix is incorporated within the crystals. The concentric matrix layers of different density are angled according to the crystal lattice. These findings indicate that the organic matrix arose from a mucinous surface coat, at least in the radially striated calculi. The crystals continued to grow in this gel-state milieu, either thrusting the matrix aside or incorporating it within the crystals. 相似文献
23.
Ryoji Kajiwara Takahiro Matsuno Osamu Ishida Toru Sunagawa Osami Suzuki Mitsuo Ochi 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2004,38(6):373-375
We report a case of an anterior interosseous nerve palsy after closed reduction and percutaneous pinning of open fractures of the radius and ulna in an adult. Operative findings showed that the anterior interosseous nerve was trapped between the distal and proximal part of the fractured radius. Treatment by neurorrhaphy gave a satisfactory result. 相似文献
24.
Chukwudi Ochi Onyeaso 《American journal of orthodontics and dentofacial orthopedics》2004,126(5):604-607
The objective of this study was to determine the prevalence of malocclusion among predominantly Yoruba adolescents in Ibadan, Nigeria, and to compare the results with those of other authors. The sample for this epidemiological survey comprised 636 secondary school students, (334 [52.5%] boys and 302 [47.5%] girls), aged 12-17 years (mean age, 14.72 +/- 1.16 SD). The subjects were randomly selected, and none had received previous orthodontic treatment. Occlusal anteroposterior relationships were assessed based on the Angle classification. Other variables examined were overjet, overbite, crowding, and midline diastema. The results showed that about 24% of the subjects had normal occlusions, 50% had Class I malocclusions, 14% had Class II malocclusions, and 12% had Class III malocclusions. Over 66% had normal overbites, and 14% and 9% had increased and reduced values, respectively. Overjet relationship was normal in 66%, increased in 16%, and decreased in 8%. Crowding was observed in 20% of the subjects and midline diastema in 37%. No statistically significant differences were observed for any occlusal variables (P > .05). Class I malocclusion is the most prevalent occlusal pattern among these Nigerian students. Different patterns of Class II and Class III might be present for the dominant ethnic groups in the country. Therefore, a survey of the occlusal pattern in southeastern Nigerians (Ibo ethnic group) would appear to be worthwhile. 相似文献
25.
Masataka Deie Yoshio Sumen Nobuo Adachi Atsuo Nakamae Ayato Miyamoto Atsushi Kanaya Mitsuo Ochi 《Knee surgery, sports traumatology, arthroscopy》2007,15(1):61-66
The purpose of this study was to examine the long-term clinical results of meniscus transplantation for articular cartilage
defects in the knee joint. The type of study was case series. From October 1990 to June 1995, eight cases underwent allogenic
or autogenic meniscus transplantations for articular cartilage defects, and seven cases were available for follow-up evaluations.
The age at surgery ranged from 14 to 42 years of age (average 22.5). In one case, transplantation of tissue-engineered cartilage
was performed due to pain 5 years after surgery. The other six cases were followed up for 8–13 years (average 10.1). The size
of the cartilage defect ranged from 1.0 to 6.3 cm2 (average 2.8 cm2). Patients were evaluated with the Lysholm score and MR images. We also performed arthroscopic examinations in three cases
at the final evaluation. This study leads to the conclusion that meniscus transplantation for articular cartilage damage is
not comparable to autologous chondrocyte transplantation. Two cases showed a good clinical outcome but the tissue remained
as fibrocartilage tissue in the long-term. 相似文献
26.
Yuka Takakura Hiroyuki Murai Hirokazu Furuya Hirofumi Ochi Jun-ichi Kira 《Clinical neurology》2005,45(5):346-350
A 74-year-old woman suffered from progressive muscle atrophy and weakness of her arms since she was seventy two years old. Before referral to our department, she was diagnosed as having cervical spondylotic myeloradiculopathy and received spinal fusion. Though spinal decompression was successful, muscle weakness of her upper limbs were progressive even after the surgery. On admission, neurological examinations revealed marked atrophy and weakness of her bilateral upper limbs with absent deep tendon reflexes showing man-in-the-barrel syndrome. Her lower extremities had normal muscle strength, but fasciculations were seen in her all four limbs. Electrophysiologically, motor nerve conduction velocity was almost normal but the amplitude was remarkably decreased, conduction block was not detected, and electromyography showed neurogenic patterns on her all extremities. Spinal progressive musclar atrophy (SPMA) accompanied with Sj?gren's syndrome was the likely diagnosis. Because 50 kDa anti-neuronal antibodies were found in her serum, we assumed that anterior horn cells were impaired by an autoimmune mechanism. Thus we treated her with corticosteroid pulse therapy, plasma exchange (PE) and intravenous immunoglobulin infusion therapy (IVIG). Although steroid pulse therapy only had a minimal effect, PE and IVIG promoted a remarkable improvement on her weakness, and the effect lasted for about three months. This is the first case of SPMA with Sj?gren's syndrome which showed good response to PE and IVIG in the early course of the disease. We considered that some SPMA-like motor neuron syndrome accompanied with autoimmune features may require immunomodulating therapies. 相似文献
27.
Yoshito Matsui Tomoatsu Kimura Noriyuki Tsumaki Haruhiko Nakahara Nobuhito Araki Natsuo Yasui Takahiro Ochi 《Journal of orthopaedic science》1996,1(2):130-135
Recent DNA studies performed by several groups have detected mutations of the gene encoding fibroblast growth factor receptor
3 (FGFR3) in patients with achondroplasia-group disorders, including achondroplasia (ACH), hypochondroplasia (HCH), and thanatophoric
dysplasia (TD). For this study, we analyzed theFGFR3 gene in 31 Japanese patients with typical ACH, four with HCH, three with a condition intermediate between ACH and HCH (ACH/HCH-intermediate),
and one with TD. Of the 31 typical ACH patients, 29 showed a G1138 to A transition and the other two a G1138 to C transversion,
both resulting in a common Gly380Arg substitution in the transmembrane domain of FGFR3. The one TD and the four HCH patients
did not display any mutations in the transmembrane domain of FGFR3. Of the three ACH/HCH-intermediate cases, one patient showed
the Gly380Arg substitution and one did not, and further analysis of the second patient revealed the presence of Asn540Lys
substitution. The first patient was, therefore, genotypically diagnosed as ACH and the second as HCH. Peripheral blood leukocyte
DNA analysis in the remaining ACH/HCH-intermediate patient indicated an unequal ratio of mutant to normal PCR products, possibly
representing a somatic mosaic for the Gly380Arg mutation. Analysis of the common FGFR3 mutation thus appears to help in the
molecular diagnosis of patients with achondroplasia-group disorders. 相似文献
28.
Tohru Hashimoto M.D. Hironobu Nakamura Shinichi Hori Kaname Tomoda Katsuyuki Nakanishi Takamichi Murakami Takahiro Kozuka Morito Monden Mitsukazu Gotoh Chikazumi Kuroda Kenichi Wakasa Masami Sakurai 《Cardiovascular and interventional radiology》1995,18(2):82-86
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis
of microscopic and macroscopic findings postembolization.
Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients
who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the
basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding
type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings:
single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth
type.
Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing
type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis)
to the SNE type (21%), and the other types (9%). 相似文献
29.
A female patient with a clinical picture of Turner's syndrome had five separate malignant tumors (three squamous cell carcinomas of the tongue, a colon cancer, and a glioblastoma multiforme). Her peripheral blood cells showed a 45,X/46,XXp-/46,XX/47,XXX mosaicism. The findings are discussed in relation to other extragonadal tumors in Turner's syndrome reported to-date. 相似文献
30.
Takahashi S Ogasawara H Hiwatashi K Hata K Hori K Koizumi Y Sugiyama T 《Biomedical research (Tokyo, Japan)》2005,26(3):117-121
Our recent studies have demonstrated that the middle domain of N-acetyl-D-glucosamine (GlcNAc) 2-epimerase participates in the specificity for and binding of nucleotides. To identify the residue conferring nucleotide binding, amino acid substitutions were introduced in the human and rat GlcNAc 2-epimerases. The mutational analyses indicate that residue 171 of GlcNAc 2-epimerase is critical for the nucleotide binding of GlcNAc 2-epimerase. 相似文献