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91.
92.
We report a case of primary gastric choriocarcinoma with liver metastasis. The mixed histologic patterns included adenocarcinoma, undifferentiated carcinoma, and choriocarcinoma. Immunohistologic staining for the beta-subunit of human chorionic gonadotrophin (beta-HCG) showed positive results in the choriocarcinoma, adenocarcinoma, and normal mucosal gland. However, positive HCG cells were present at different intensities in the choriocarcinoma, adenocarcinoma, and normal mucosal gland. The level of HCG was significantly increased in serum. This unusual tumor probably resulted from dedifferentiation of a primary adenocarcinoma or developed directly from the mucosal glands. 相似文献
93.
94.
WL Bloss 《Canadian Metallurgical Quarterly》1991,44(15):8035-8042
95.
96.
97.
HC Champion JA Santiago MA Czapla TJ Bivalacqua C Ilgenfritz PJ Kadowitz 《Canadian Metallurgical Quarterly》1997,18(9):1357-1364
Responses to T-kinin and bradykinin were compared in the mesenteric vascular bed of the cat. Under constant-flow conditions, injection of T-kinin and bradykinin into the perfusion circuit induced similar dose-related decreases in perfusion pressure. Responses to T-kinin and bradykinin were inhibited by the kinin B2 receptor antagonist Hoe-140, but were not altered by the B1 receptor antagonist des-Arg9-[Leu8]-BK, the histamine H1 antagonist pyrilamine, the histamine H2 receptor antagonist cimetidine, or the H3 receptor antagonist thioperamide. Vasodilator responses to T-kinin and bradykinin were attenuated by the nitric oxide synthase inhibitor, N omega Nitro-L-arginine methyl ester (L-NAME), but were not altered by the cyclooxygenase inhibitor, sodium meclofenamate, or the K+ ATP channel antagonist, U37883A. These data suggest that vasodilator responses to T-kinin and bradykinin are mediated by kinin B2 receptor stimulated release of nitric oxide from the endothelium, but that the activation of kinin B1 receptors, the release of vasodilator prostaglandins, or the opening of K+ ATP channels are not involved in the response to T-kinin in the mesenteric vascular bed of the cat. 相似文献
98.
Salvage of lower-extremity Gustilo type IIIC fractures is difficult, time-consuming for the patients and physicians, and not universally successful because of poor functional outcomes. Even if successful with limb salvage, the functional result may be unsatisfactory because of mutilating injuries to muscle and nerve, bone loss, and the presence of chronic infection. From July 1991 until July 1994, revascularizations of open IIIC fractures were attempted for wounds with Mangled Extremity Severity Score (MESS) < or = 10. The functional results were evaluated at 2 years after injury. Thirty-six lower-extremity revascularizations were performed on 34 patients, including 1 patient with bilateral distal tibial IIIC fractures and a child with IIIC femoral fracture accompanied by ipsilateral distal tibial amputation. Excluded were patients with below-ankle IIIC fractures as well as patients who underwent immediate amputation at admission. After the revascularization, seven patients with IIIC fractures (7 of 36, 19.4%) underwent secondary amputation within 1 week. At the 2-year follow-up, the overall secondary amputation rate was 25% (9 of 36) and the salvage rate was 75% (27 of 36). Those were no deaths. Of the 29 salvaged limbs among these 27 patients, 23 limbs (23 of 29, 79.3%) required secondary coverage procedures that included 12 free flap transfers (12 of 29, 41.4%). Every patient needed subsequent reconstructive surgery to achieve an acceptable functional result. In this series, MESS was able to predict the secondary amputation rate and the functional result. Sixteen of the 17 limb-salvaged patients with MESS < or = 7 were able to achieve minimal functional requirements, whereas 3 of the 10 patients with MESS = 8 to 10 failed to achieve minimal functional requirements at the 2-year follow-up. Using statistical analysis, we found that the salvaged limbs with MESS < or = 9 exhibited a significant difference in achieving adequate function compared with limbs with MESS > 9. Using our protocol for treatment for IIIC fractures, the threshold for immediate amputation can be raised from MESS = 7 to MESS = 9. Our conclusions are (1) more severely injured limbs have poor functional results, (2) every patient needs subsequent reconstructive surgery, and (3) the MESS may be helpful in decision-making. 相似文献
99.
DNA replication origins in chromosomes of eukaryotes are activated according to a temporal program. In the yeast Saccharomyces cerevisiae, activation of origins in early S phase appears to be a default state. However, cis-acting elements such as telomeres can delay origin activation until late S phase. Site-specific recombination was used to separate origin from telomere in vivo, thereby demonstrating that the signal for late activation is established between mitosis and START in the subsequent G1 phase. Once set, the signal can persist through the next S phase in the absence of the telomere. Establishment of the temporal program and of initiation competence of origins may be coincident events. 相似文献
100.
Atef Rebhi Thabet Makhlouf Yannick Champion Jean-Philippe Couzinié Nabil Njah 《Journal of Materials Science》2011,46(7):2185-2193
Microstructure evolution of 99.1% aluminum after equal-channel angular extrusion (ECAE) and subsequent heat-treatment was
investigated. After deformation the samples were annealed at different temperatures. The deformed and annealed states were
characterized by Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), and microhardness tests. It was shown that
the observed microstructure changes during subsequent annealing have to be associated with recovery and cells formation. The
initial stages of recovery were investigated using weak-beam technique. The microstructure obtained after annealing for 1 h
at 100 °C consists of some arrangements of the dislocations into sub-grain boundaries within the wide preexisting grains.
Annealing at 300 °C led to the appearance of a duplex microstructure consisting of bands of slightly coarsened grains associated
with refined grains. No growth of dislocation cells was observed up to 400 °C. In XRD measurements, the lattice parameter
increase with subsequent heating. This indicates a continuous grain growth during annealing. This is due to the important
increase of coherency length, D observed parallel to a substantial decrease of rms-strain, ε. 相似文献