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91.
In a patient who had undergone construction of a continent ileal pouch we successfully repaired an incontinent ileal tube by infolding it in an imbricated portion of the ileal pouch wall. For 2 years postoperatively the patient has been urine continent and has catheterized the pouch easily. We believe this infolding technique is useful for reconstructing the continent mechanism in patients with incompetent ileal valves.  相似文献   
92.
The study examines the osteoinductive potential of recombinant human morphogenetic protein 2 (rhBMP-2) radiologically and histologically in rat calf muscle.Ten male Wistar rats were used. rhBMP-2 50 μg was implanted with atelopeptide type I collagen as carrier in a pouch in rat calf muscle (n=5), and atelopeptide type I collagen alone was implanted in a further five as control. Induction of osteogenesis at 4 weeks was investigated.In all rats in which rhBMP-2 had been implanted there was a radio-opaque shadow in the muscle in the soft tissue radiograph. No such shadows were noted in the control group. Histological examination showed bony trabeculum, osteoblasts, and vigorous bone marrow including fatty marrow and angioid tissue both at the margins and in the center of the excised lumps in the rhBMP-2 group. There were no such signs in the control group.rhBMP-2 may be capable not only of inducing the formation of bone, but also of inducing a ‘self-supporting bone organ’ in the muscle.  相似文献   
93.
The calcifying odontogenic cyst (COC) presents with diverse hlstologlcal features; thus, several subclasslfl-cations have been proposed. To evaluate the slgnlficance of the various histological features and subtypes of COC from the perspectlve of proliferative activity, the proliferating cell nuclear antigen (PCNA) labellng index (LI; the percentage of positive nuclei) was assessed immunohistochemlcally in 25 cases of COC (21 benign and four malignant). All of the benign cases were of the cystic variety and further subclas-sified into non-proliferative subtype (NPS; four cases); proliferative subtype (PS; eight cases); and COC associated with odontoma (COCaO, nlne cases). The PCNA U of the mallgnant COC (65.2 ± 5.6) was slgnlflcantly higher than that of the benlgn COC (11.6 ± 9.0; P = 0.002). Non-proliferative subtype (6.8 ± 2.8) showed the lowest PCNA LI and PS (17.2 ± 11.2) the highest of among the three subtypes of benign cystic COC (P = 0.028). In nine cases of COCaO, six showed epithelial lining of the non-proliferative type as NPS and the other three had lining wlth proliferative features as PS. The PCNA LI of the latter COCaO group (14.3 ± 6.6) was significantly higher than that of the former (6.1 ± 4.3; P = 0.05), as Seen between PS and NPS. These results demonstrate that PCNA LI is a possible parameter for differentiating mallgnant COC from benign COC and, whatever the subtypes, the proliferative features In the lining are the main factor influencing the prollferatlng actlvity of COC.  相似文献   
94.
J Ogawa  T Tsurumi  H Inoue  A Shohtsu 《Cancer》1992,69(7):1688-1695
Seventy-four patients with lung cancer, resected consecutively from April 1989 to August 1990, were divided into (1) 21 with diploid tumors having a single G0/G1 peak and a coefficient of variation (CV) of 4.9 or less, (2) 18 with peridiploid tumors having a single G0/G1 peak and a CV at 5.0 or more, and (3) 35 with aneuploid tumors having multiple G0/G1 peaks. Aneuploid tumors had higher frequencies of lymphatic invasion and metastasis to the mediastinal lymph nodes. To evaluate the relationship between ploidy tumor status and immunologic competence of the regional lymph nodes, histologic findings and the proportion of killer T-lymphocytes were examined in the dissected lymph nodes. Aneuploid tumors had significantly lower proportions of paracortical hyperplasia and killer T-lymphocytes than did diploid and peridiploid ones in the nonmetastatic lymph nodes of N0 and N1 disease. These findings suggest the possibility that a decline in the antitumor competence of these lymph nodes could cause metastasis to the nodes. The recurrence rates were 19% in diploid, 33% in peridiploid, and 54% in aneuploid tumors, and the 2-year survival rates were 87%, 78%, and 44%, respectively. Peridiploid tumors showed intermediate values between diploid and aneuploid in terms of immunologic competence, recurrence rate, and survival. They were assumed to have a different proportion of aneuploid cells than the other two.  相似文献   
95.
p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 ± 10% in the staged group and 83 ± 9% in the simultaneous group (p= 0.79). Mean follow-up was 13 ± 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring an optimal intraoperative postangioplasty result.  相似文献   
96.
97.
Eosinophilic bronchitis without asthma can cause a persistent non-productive cough which is resistant to bronchodilator therapy. To understand the mechanism of the cough in this disorder, an animal model of eosinophilic bronchitis was developed. Guinea-pigs were treated with transnasal administration of polymyxin B or saline twice a week for 3 weeks. The number of eosinophils in bronchoalveolar lavage fluid increased in polymyxin B-treated animals when compared with those treated with saline. In addition, histological examination showed that the number of eosinophils infiltrated into the tracheal epithelium increased; injury to the tracheal epithelium was greater in polymyxin B-treated animals. The numbers of coughs induced by saline and each concentration of capsaicin (10–18, 10–16, 10–14M) were greater in the polymyxin B-treated animals. FK-224 (a neurokinin receptor antagonist) decreased the heightened cough reflex in this animal model of eosinophilic bronchitis. These findings suggest that neuropeptides, and particularly neurokinins, are involved in the heightened cough receptor sensitivity in eosinophilic bronchitis without asthma. This has implications for better understanding of this disorder and its treatment.  相似文献   
98.
In an effort to augment the anti-Helicobacter pylori effect of amoxicillin, mucoadhesive microspheres, which have the ability to reside in the gastrointestinal tract for an extended period, were prepared. The microspheres contained the antimicrobial agent and an adhesive polymer (carboxyvinyl polymer) powder dispersed in waxy hydrogenated castor oil. The percentage of amoxicillin remaining in the stomach both 2 and 4 h after oral administration of the mucoadhesive microspheres to Mongolian gerbils under fed conditions was about three times higher than that after administration in the form of a 0.5% methylcellulose suspension. The in vivo clearance of H. pylori following oral administration of the mucoadhesive microspheres and the 0.5% methylcellulose suspension to infected Mongolian gerbils was examined under fed conditions. The mucoadhesive microspheres and the 0.5% methylcellulose suspension both showed anti-H. pylori effects in this experimental model of infection, but the required dose of amoxicillin was effectively reduced by a factor of 10 when the mucoadhesive microspheres were used. In conclusion, the mucoadhesive microspheres more effectively cleared H. pylori from the gastrointestinal tract than the 0.5% methylcellulose suspension due to the prolonged gastrointestinal residence time resulting from mucoadhesion. A dosage form consisting of mucoadhesive microspheres containing an appropriate antimicrobial agent should be useful for the eradication of H. pylori.  相似文献   
99.
Background: The Rho/Rho-kinase signaling pathway plays an important role in mediating Ca2+ sensitization of vascular smooth muscle. The effect of anesthetics on Rho/Rho-kinase-mediated vasoconstriction has not been determined to date. This study is designed to examine the possible inhibitory effects of sevoflurane on the Rho/Rho-kinase pathway by measuring guanosine 5'-[[gamma]-thio]triphosphate (GTP[gamma]S)-stimulated contraction and translocation of RhoA (one of the three Rho subtypes) and Rock-2 (one of the two Rho-kinase subtypes) from the cytosol to the membrane in rat aortic smooth muscle.

Methods: GTP[gamma]S-induced contraction of rat aortic endothelium-denuded rings was measured using an isometric force transducer, and GTP[gamma]S-stimulated membrane translocation of RhoA and Rock-2 in smooth muscle cells was detected with Western blotting in the presence and absence of sevoflurane.

Results: GTP[gamma]S (10-4 m) induced a sustained contraction, which was significantly inhibited by the Rho-kinase inhibitor, Y27632 (3 x 10-6 m). Before treatment with GTP[gamma]S, RhoA and Rock-2 were detected primarily in the cytosolic fraction. GTP[gamma]S (10-4 m) stimulated the translocation of RhoA and Rock-2 from the cytosol to the membrane, which was sustained for more than 60 min. Sevoflurane (1.7, 3.4, and 5.1%) concentration dependently inhibited the GTP[gamma]S-induced constriction of rat aortic smooth muscle with a reduction of constriction of 52-75% (P < 0.01, n = 8), and attenuated the translocation of RhoA and Rock-2 by 31-66% and 34-78%, respectively (P < 0.05-0.01, respectively; n = 4).  相似文献   

100.
A 50-year old man who had acute type A aortic dissection, underwent prosthetic graft replacement of the ascending aorta. Intimal laceration of the ascending aorta was extending into the noncoronary Valsalva sinus just near the aortic annulus, but the competency of the aortic valve was preserved. Reconstruction of the noncoronary sinus was achieved by approximating intimal edge with Teflon felt reinforced buttress suture, then the ascending aorta was replaced by a Dacron prosthetic graft. His postoperative recovery was uneventful.  相似文献   
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