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71.
72.
Identification and functional characterization of a sex pheromone receptor in the silkmoth Bombyx mori 总被引:7,自引:0,他引:7
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Sakurai T Nakagawa T Mitsuno H Mori H Endo Y Tanoue S Yasukochi Y Touhara K Nishioka T 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(47):16653-16658
Sex pheromones released by female moths are detected with high specificity and sensitivity in the olfactory sensilla of antennae of conspecific males. Bombykol in the silkmoth Bombyx mori was the first sex pheromone to be identified. Here we identify a male-specific G protein-coupled olfactory receptor gene, B. mori olfactory receptor 1 (BmOR-1), that appears to encode a bombykol receptor. The BmOR-1 gene is located on the Z sex chromosome, has an eight-exon/seven-intron structure, and exhibits male-specific expression in the pheromone receptor neurons of male moth antenna during late pupal and adult stages. Bombykol stimulation of Xenopus laevis oocytes expressing BmOR-1 and BmGalphaq elicited robust dose-dependent inward currents on two-electrode voltage clamp recordings, demonstrating that the binding of bombykol to BmOR-1 leads to the activation of a BmGalphaq-mediated signaling cascade. Antennae of female moths infected with BmOR-1-recombinant baculovirus showed electrophysiological responses to bombykol but not to bombykal. These results provide evidence that BmOR-1 is a G protein-coupled sex pheromone receptor that recognizes bombykol. 相似文献
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Norihiro Sato Kei Yabuki Kazunori Shibao Yasuhisa Mori Toshihisa Tamura Aiichiro Higure Koji Yamaguchi 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(2):177-182
Background: A prolonged operative time is associated with adverse post-operative outcomes in laparoscopic surgery. Although a single-incision laparoscopic cholecystectomy (SILC) requires a longer operative time as compared with a conventional laparoscopic cholecystectomy, risk factors for a prolonged operative time in SILC remain unknown.Methods: A total of 20 clinical variables were retrospectively reviewed to identify factors for a prolonged operative time (longer than 3 h) in a total of 220 consecutive patients undergoing SILC.Results: The median operative time was 145 min (range, 55–435) and a prolonged operative time was required in 62 patients (28%). Independent factors that predict a prolonged operative time as identified through multivariate analysis were body mass index (BMI) (P = 0.009), acute cholecystitis (P < 0.001) and operator (resident or staff surgeon) (P < 0.001). Furthermore, a prolonged operative time was significantly associated with an increased amount of intra-operative blood loss (P < 0.001) and a prolonged stay after surgery (P < 0.001).Conclusions: These findings suggest that a higher BMI, acute cholecystitis and a resident as an operator significantly increase the duration of SILC procedures. 相似文献
75.
76.
Sugiura R Ogawa H Oka T Koyanagi R Hagiwara N;HIJ-CREATE Investigators 《The American journal of cardiology》2012,109(4):576-580
The aim of the present study was to clarify the influence of candesartan-based therapy on subsequent carcinogenesis and cancer death in patients with coronary artery disease with hypertension in a substudy of a multicenter, prospective, randomized, controlled trial. That trial compared the effects of candesartan-based therapy with those of non-angiotensin receptor blocker (ARB)-based standard therapy on major adverse cardiovascular events. Hypertensive patients with coronary artery disease were randomly assigned to receive either candesartan-based (n = 1,024) or non-ARB-based pharmacotherapy, including angiotensin-converting enzyme inhibitors (n = 1,025). During a median follow-up of 4.2 years, 1,606 adverse events (798 in the candesartan group and 808 in the non-ARB standard group) were reported. Among them, new cancer occurred in 5.37% of subjects in the candesartan group and 5.66% of subjects in the standard therapy group (hazard ratio 0.95, 95% confidence interval 0.65 to 1.38). Cancer deaths occurred in 1.66% in the candesartan group and 2.44% in the standard therapy group, respectively (hazard ratio 0.74, 95% confidence interval 0.39 to 1.39). Kaplan-Meier estimates of survival without new cancer and cancer deaths demonstrated that candesartan-based therapy does not accelerate the occurrence of new cancer (log-rank, p = 0.84) or cancer death (p = 0.39) compared to standard therapy. Advanced age and male gender were independently and significantly correlated with the subsequent incidence of cancer. In conclusion, the results of the present study suggest that candesartan-based therapy is not associated with either carcinogenesis or cancer death compared to non-ARB standard therapy. 相似文献
77.
We report a patient with ventral simultanagnosia, prosopagnosia for “unfamiliar faces” (dorsal prosopagnosia), spatial agraphia, and constructional disorder, particularly on the left spatial side, due to a lesion in the right posterior superior and middle temporal gyri and angular gyrus. The patient showed impairment of fundamental visual and visuospatial recognition, such as in object size, configuration, and horizontal point location, which probably underlay the mechanism of simultanagnosia and prosopagnosia. This case also suggests that the coexistence of simultanagnosia and prosopagnosia results from a right hemispheric insult, and damage to the temporoparietal area interrupts the incorporation of spatial information into object recognition. This disconnection of information flow, together with impaired object recognition per se, may impair the parallel processing of multiple objects, leading to object-by-object or part-by-part recognition. 相似文献
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79.
Tsutsumi K Ohtsuka T Mori Y Fujino M Yasui T Aishima S Takahata S Nakamura M Ito T Tanaka M 《Journal of gastroenterology》2012,47(6):678-685
Background
Because of the rarity and variety of pancreatic neuroendocrine tumors (PNETs), there have been few reports regarding the indication for lymph node dissection in patients with these tumors. This study aimed to evaluate the risk of lymph node metastasis of PNETs based on the tumor size and hormonal production.Methods
Data for a total of 66 patients who had PNETs resected at our department between 1987 and 2010 were retrospectively studied. The clinicopathological features, including the disease-specific survival rate, were assessed based on the status of lymph node metastasis at the time of initial surgical resection. Then the cut-off point of tumor size to predict lymph node metastasis was estimated.Results
There were 12 patients (18%) with lymph node metastasis. The frequency of lymph node metastasis tended to be higher in gastrinomas than that in other tumors (43 vs. 15%; P?=?0.08). The size of PNETs with lymph node metastasis was significantly larger than that of the PNETs without metastasis (P?=?0.04). The postoperative survival rate in the PNET patients with lymph node metastasis was significantly lower than that in the patients without metastasis (P?0.0001). Only 2 (8%) of 26 PNETs with a tumor size of <15?mm had lymph node metastasis, and both of these were gastrinomas. On the other hand, 10 (25%) of the remaining 40 PNETs with a tumor size of ≥15?mm had lymph node metastasis. Notably, there were no PNETs with lymph node metastasis in 22 non-gastrinomas with a tumor size of <15?mm.Conclusions
Non-gastrinomas with a tumor size of ≥15?mm and all gastrinomas would be an indication for pancreatectomy with lymph node dissection. 相似文献80.
Watanabe T Urano E Miyauchi K Ichikawa R Hamatake M Misawa N Sato K Ebina H Koyanagi Y Komano J 《AIDS research and human retroviruses》2012,28(8):913-922
Rho GTPases are able to influence the replication of human immunodeficiency virus type 1 (HIV-1). However, little is known about the regulation of HIV-1 replication by guanine nucleotide dissociation inhibitors (GDIs), one of the three major regulators of the Rho GTPase activation cycle. From a T cell-based cDNA library screening, ARHGDIB/RhoGDIβ, a hematopoietic lineage-specific GDI family protein, was identified as a negative regulator of HIV-1 replication. Up-regulation of ARHGDIB attenuated the replication of HIV-1 in multiple T cell lines. The results showed that (1) a significant portion of RhoA and Rac1, but not Cdc42, exists in the GTP-bound active form under steady-state conditions, (2) ectopic ARHGDIB expression reduced the F-actin content and the active forms of both RhoA and Rac1, and (3) HIV-1 infection was attenuated by either ectopic expression of ARHGDIB or inhibition of the RhoA signal cascade at the HIV-1 Env-dependent early phase of the viral life cycle. This is in good agreement with the previous finding that RhoA and Rac1 promote HIV-1 entry by increasing the efficiency of receptor clustering and virus-cell membrane fusion. In conclusion, the ARHGDIB is a lymphoid-specific intrinsic negative regulator of HIV-1 replication that acts by simultaneously inhibiting RhoA and Rac1 functions. 相似文献