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Embryonic stem (ES) cells deficient in poly(ADP‐ribose) polymerase‐1 (Parp‐1) develop into teratocarcinomas with the appearance of trophoblast giant cells (TGCs) when injected subcutaneously into nude mice. Because the uterus is one of the original organs in which germ cell tumors develop with induction of trophoblast lineage, here we investigated whether Parp‐1 deficiency in ES cells affects teratocarcinoma formation processes by grafting ES cells into the horns of uteri. Teratocarcinomas developed from both wild‐type (Parp‐1+/+) and Parp‐1?/? ES cells. The weights of the tumors derived from Parp‐1?/? ES cells were lower than those of the tumors derived from Parp‐1+/+ ES cells (P < 0.05). The Parp‐1?/? tumors showed the appearance of TGCs. Notably, organ metastasis to the lung and liver was observed for the Parp‐1?/? tumors, but not for the Parp‐1+/+ tumors (P < 0.05). Invasions were more frequently observed with the Parp‐1?/? tumors compared with the Parp‐1+/+ tumors (P < 0.05). Since TGCs are known to have invasive properties, the appearance of TGCs may have supported the metastatic process. The present findings suggest that loss of Parp‐1 during teratocarcinoma formation might augment invasive and metastatic properties of the tumors in the uterine environment.  相似文献   
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This study describes a novel technique for skeletonization and isolation of Glissonean and venous branches during liver surgery using a harmonic scalpel (HS). Hepatic resections with HS were performed with the skeletonization and isolation technique in 50 patients (HS group). Variables evaluated were blood loss, operative time, biliary leak, and morbidity. The results were compared with 50 hepatic resections that were performed using a previously established technique: Cavitron ultrasonic surgical aspirator with electric cautery, ligatures, and hemoclips (NHS group). The HS group had shorter total operative times (285 versus 358 minutes; P = 0.01), less blood loss (389 versus 871 mL; P = 0.034), and less crystalloid infusion (2744 versus 3299 mL; P = 0.027) compared with the NHS group. Postoperative liver function and complication rates were similar when comparing the two groups. These data demonstrate that HS is a simple, easy, and effective instrument for the skeletonization and isolation of vessels during liver transection.Key words: Liver resection, Ultrasonic scalpel, Skeletonization, Cavitation effectVarious devices are available for liver transection, but the availability of comparative data for transection techniques is limited by the diversity of operative procedures. Clamp crushing (CC) and a Cavitron ultrasonic surgical aspirator are widely used for splitting the liver parenchyma,1,2 and hemostasis is achieved by bipolar coagulation, ligatures, or hemoclips. Various coagulating devices, such as Ligasure,3 Tissuelink,4 and the Harmonic Scalpel (HS),57 have recently been developed to aid in liver splitting. The choice of instrument is often based on individual surgeon preference. Higami et al8,9 described a novel technique to skeletonize and harvest the internal thoracic artery with the HS, and the present study capitalizes on their experience to describe a unique method to skeletonize and isolate the Glissonean and venous branches using an HS.  相似文献   
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Recent advances in optical imaging with two-photon excitation microscopy have enabled visualization of the inside of intact bone tissues in living animals. Using these advanced techniques, the dynamic behaviors of live bone cells and static histological information on bone tissue structures can be elucidated. The migration and positioning of osteoclast precursor monocytes, the bone-resorbing function of mature osteoclasts, and its functional coupling with bone-replenishing osteoblasts have been evaluated, including their dynamic properties in intact live bones. This novel ‘bone histodynametric’ methodology, combined with conventional histomorphometric analyses, will surely contribute to opening of a new era in bone and mineral research.  相似文献   
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Information on obstructive sleep apnea-hypopnea syndrome (OSAHS) in Japan has been limited. The purposes of this clinical study were to evaluate the demographic characteristics of Japanese OSAHS patients and to assess how demographic factors are associated with OSAHS severity. We analyzed 3,659 OSAHS patients who underwent polysomnographic evaluation between January 2000 and December 2004 at 11 hospitals in Niigata Prefecture, Japan. Data consisted of apnea-hypopnea index (AHI) and demographic characteristics, including sex, age, and body-mass index, for statistical analysis. Levels of obesity were classified according to the WHO criteria. The male-to-female patient ratio for OSAHS was 4.6, and male patients presented more severe OSAHS than female patients. High AHI and a high proportion of moderate to serious OSAHS (AHI > or = 15) were found among the patients in their 30s, as well as female patients in their 70s and male patients in their 80s. The AHI and the proportion of moderate-to-serious OSAHS (AHI > or = 15) were greater in patients classified as underweight than in normal weight patients. In conclusion, there is a higher male predominance in the prevalence of OSAHS, and in both sexes, the results suggest different pathophysiological mechanisms of deteriorating OSAHS between adults under age 55 and adults 55 years or over. In addition, underweight patients exhibit more severe OSAHS than normal weight patients.  相似文献   
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