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91.
Seiya Kikuchi Akira Ingu Masayoshi Ito 《Annals of thoracic and cardiovascular surgery》2005,11(5):320-323
We report an 18-month-old boy with the association of pectus excavatum and tetralogy of Fallot (TOF). We successfully performed simultaneous pectus repair using sternal elevation without any prosthetic support and total correction of TOF after a prior modified Blalock-Taussig shunt. Retracting a divided costo-sternal complex with a rectus abdominal flap away from the operative field before the cardiac operation provided excellent surgical exposure. The modified Blalock-Taussig shunt prior to the combined repair prevented life-threatening hypoxic spells during dissection of the deformed sternum and costochondral cartilages before institution of cardiopulmonary bypass. 相似文献
92.
Akio Tanaka Motoyoshi Okamoto Dai Yoshizawa Shigeru Ito Patricia González Alva Fumio Ide Kaoru Kusama 《Journal of oral pathology & medicine》2007,36(7):400-404
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas. 相似文献
93.
An attempt was made to detect a pancreatic tumor antigen (PTA) in transplantable pancreatic adenocarcinomas induced by N-bis(2-hydroxypropyl)nitrosamine (DHPN) in hamsters. Antibody against antigenic protein was raised by immunizing rabbits with whole homogenate of the tumors transplanted into the back of hamsters. PTA was purified by affinity chromatography and shown to have the physicochemical properties of a glycoprotein with a molecular weight of 800,000, migrating in the beta regions upon agarose gel electrophoresis. Loss of immunological properties was observed after heating at 65 degrees C for 30 min. Enzyme immunoassay revealed that the levels of PTA in the serum and tissue showed a positive correlation with the induction of the presence of tumor, and size of the tumor. It is tentatively suggested that PTA values above 150 ng/ml serum are indicators of tumors, because in normal hamsters the PTA range is from 25 to 130 ng/ml serum. Immunohistochemically, PTA was demonstrated to be localized within the cytoplasm of epithelial tumor cells of well-differentiated tubular adenocarcinomas. 相似文献
94.
The neural control of smooth muscle cells in the corpus spongiosum, helicine artery and bulbus glandis of the dog was investigated in relation to the mechanism involved in erection, using isometric tension recording and micro-electrode methods. In the corpus spongiosum, field stimulation evoked twitch-like contractions followed by relaxations. These relaxations were enhanced and prolonged by neostigmine and partly suppressed by atropine. Guanethidine abolished the twitch-like contractions and increased muscle tone. The relaxations observed after pre-treatment with guanethidine were abolished by tetrodotoxin (TTX), thereby indicating that these muscles are innervated by adrenergic excitatory, cholinergic and non-adrenergic non-cholinergic inhibitory nerves. In the helicine artery and bulbus glandis, field stimulation evoked contractions and these contractions were abolished by guanethidine or TTX, indicating that these muscles are innervated by adrenergic excitatory nerve fibres. After pre-treatment with guanethidine and atropine, muscle relaxation appeared in response to field stimulation in the helicine artery but not in the bulbus glandis, indicating that the helicine artery in the corpus spongiosum is also innervated by non-adrenergic non-cholinergic inhibitory nerves in addition to the excitatory adrenergic nerves. In the smooth muscle cells of the corpus spongiosum, slow potential changes were correlated with spontaneous contractions and field stimulation evoked excitatory or inhibitory junction potentials. The neural mechanism involved in erection is discussed in relation to the topical difference in the autonomic innervation patterns in the corpus spongiosum, helicine artery and bulbus glandis. 相似文献
95.
Hideaki Anai Yoshihiko Maehara Tatsuo Oshiro Hideo Baba Hiroyuki Orita Toshiro Okuyama Keizo Sugimachi 《Journal of surgical oncology》1993,53(3):204-207
In 268 of the 1,115 patients (24.0%) with gastric cancer who underwent a curative resection in our clinics, the tumor was located in the middle third of the stomach. The clinicopathological features and prognosis of these patients were divided into two groups, according to site of the tumor: anterior wall (n = 58) vs. other sites (n = 210). Clinicopathological factors did not differ between the two groups. The survival time for patients with a tumor in the anterior group was shorter than that for patients with a tumor in other areas (P < 0.05). The five-year survival rate was 79.3% for patients with an anterior tumor and 91.9% for those with a tumor at a different site. A multivariate analysis indicated lymph node metastasis, serosal invasion, and anterior wall location to be independent prognostic factors indicative of a poor prognosis when the tumor was located in the middle third of the stomach. For such patients, close follow-up is needed to detect possible recurrences. © 1993 Wiley-Liss, Inc. 相似文献
96.
97.
Tatsuo Shirota Mie Tashiro Kohsuke Ohno Akira Yamaguchi 《Journal of oral and maxillofacial surgery》2003,61(4):471-480
PURPOSE: This study investigated the effect of parathyroid hormone (1-34) [PTH(1-34)] on bone reactions after tibial placement of titanium screw implants into ovariectomized rats. MATERIALS AND METHODS: Twelve-week-old female Wistar rats were divided into 3 groups of 24. The first group (Sham group) was sham-operated; the second group (OVX group) was ovariectomized only; and the third group (PTH group) was subcutaneously administered 30 microg/kg PTH in the dorsal region 3 days per week starting the fourth week after ovariectomy until the end of the experiment. Titanium screw implants were placed in the proximal metaphysis of the tibia of all 3 groups at 168 days after surgery. The animals were killed 7, 14, 28, and 56 days after implantation. Undecalcified sections were prepared and evaluated by light microscopy. Histomorphometric measurements were obtained using a computer-based image analyzer to quantify the unit bone mass around the implant and the rate of implant-bone contact. RESULTS: When PTH administration was started 21 days after ovariectomy, the volume density of bone around implants in the PTH group was almost the same as that of the Sham group throughout the entire observation period. This finding suggests that not only can intermittent human PTH(1-34) administration prevent resorption of newly generated trabeculae around an implant but also it can aid in the recovery of bone volume lost due to ovariectomy. CONCLUSION: When dental implants are applied to jaw bone showing trabecular bone loss, it may be possible to increase bone density around an implant by intermittent human PTH(1-34) administration and thereby improve clinical results. 相似文献
98.
Takashi Ito Ryuji Sakakibara MD Tatsuya Yamamoto Tomoyuki Uchiyama Zhi Liu Masato Asahina Morihiro Higashi Kimihito Arai Shoichi Ito Yusuke Awa Kaori Yamamoto Mika Kinou Tomonori Yamanishi Takamichi Hattori 《Clinical autonomic research》2006,16(1):66-71
Abstract Uro-neurological assessment was performed in four patients with small-fiber neuropathy due to amyloidosis (2 transthyretin-type/2
immunoglobulin light-chain-type). Voiding difficulties were due to detrusor weakness and impaired bladder sensation. In two
patients cholinesterase inhibition treatment caused urge incontinence, indicating detrusor denervation supersensitivity. The
underlying mechanisms of urinary dysfunction seem to involve postganglionic cholinergic and afferent somatic nerves. 相似文献
99.
100.
N Yamada M Nakamura K Ishikura M Ota T Yazu N Hiraoka H Tanaka M Ito H Fujioka N Isaka T Nakano 《International angiology》2003,22(1):50-54
AIM: In Japan, acute pulmonary thromboembolism (APTE) is still rare, but the number of patients with APTE has been steadily increasing. It is important for early diagnosis and early management of APTE to recognize epidemiological characteristics of this condition. METHODS: We investigated the epidemiological characteristics of 252 patients with APTE who were admitted to our institutions between 1975 and 2001. APTE was more prevalent in women that in men. It was observed the most in the age group between 50s to 70s, especially in women. Many patients had prolonged immobilization, recent major operation, obesity, or cancer, as risk factors for venous thromboembolism. One hundred and thirty-eight patients developed APTE in hospital; 60 patients were in Department of Internal Medicine, 28 in General Surgery, 15 in Orthopedics, 15 in Obstetrics and Gynecology, and 20 in other services. RESULTS: Among 58 patients with malignancy, 43% had cancers in digestive organs, 21% in gynecological, and 17% in urological. Among 61 patients who were examined for the presence of thrombophilia, 13 patients had inherited thrombophilia (8 protein C deficiency, 4 protein S deficiency, and 1 antithrombin III deficiency) 11 had antiphospholipid antibodies which indicated thrombophilia. Five out of the above 61 patients (8%) had no obvious risk factors including thrombophilia. CONCLUSION: The findings in our patients were almost the same as those in Western patients, except for some points. These results might be useful to establish a preventive approach for APTE in Japan. 相似文献