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71.
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The venous outlet of the corpus cavernosum is generally believed to be obstructed during erection. Some researchers, however, have demonstrated an increased venous outflow during erection. To elucidate this discrepancy, we carried out a pressure-flow study using a perfusion model of the penile deep artery in dogs. Various states of the corpus cavernosum, which were different in cavernous pressure, were induced by a delicate control of electrostimulation to the cavernous nerve. Inflow rate into the corpus cavernosum, inflow resistance and outflow resistance were simultaneously evaluated. The inflow rate in mild erection was higher than in the flaccid state, and the outflow rate was estimated to be also higher than in the flaccid state. A probable reason for the increased outflow rate was that the arterial resistance decreased remarkably, while the venous resistance only slightly increased. In full erection, both the inflow and outflow rates were lower than in the flaccid state because of a great venous resistance. Histological observation of the canine penis indicated that compression of draining veins passing through the tunica albuginea was weak in mild erection, while intense in full erection. It was proposed that in mild erection, the effect of venous occlusion was slight though that of arterial dilation was noticeable, resulting in an increase in the venous outflow. 相似文献
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Kazuki Tamura Tadayuki Oka Kazutaka Ohsawa Takehiko Koji Yoji Watanabe Shigeru Katamine Hiroshi Sato Hiroyoshi Ayabe 《The Journal of heart and lung transplantation》2003,22(4):452-459
BACKGROUND: Cytomegalovirus (CMV) diseases commonly occur in allograft recipients in the early post-transplant period. However, factors responsible for the high incidence of CMV diseases during this period are not yet fully defined. METHODS: Wistar-Furth (WF; RT-1(u)) rats were inoculated with 10(4) plaque-forming units (PFU) of rat CMV (RCMV) intraperitoneally, and then transplanted with allogeneic lungs from Dark Agouti (DA; RT-1avl) rats or stimulated with 10(7) mitomycin C-treated spleen cells from DA rats by daily sub-cutaneous injections for 2 weeks. No immunosuppressive agent was used. Naive WF rats and WF rats grafted with syngeneic lungs or cells were used as controls. The level of RCMV replication in rats was assessed by infectious virus titers in tissues. RESULTS: The virus titers in salivary glands of allogeneic and syngeneic lung graft recipients were significantly higher than in naive WF rats. The level of RCMV replication in rats stimulated with allogeneic spleen cells was significantly higher than in the syngeneic recipient rats: virus titers in the salivary gland of allogeneic and syngeneic recipients reached 4.61 +/- 0.33 and 4.00 +/- 0.37 log(10) PFU/g tissue, respectively, at 14 days post-infection (p = 0.015). The augmented viral replication in allogeneic recipients was confirmed by an increase in the number of RCMV antigen-positive macrophages present in tissue sections of the salivary gland. CONCLUSIONS: Acute lung allograft rejection and allogeneic spleen cell stimulation enhance CMV replication in the salivary gland of rats. Various responses to allogeneic antigens occurring in the process of acute allograft rejection could be risk factors for post-transplant CMV replication and infection. 相似文献
75.
Yoichi Sato Hitoshi Yokoyama Masaaki Watanabe Osami Hamada 《Annals of thoracic and cardiovascular surgery》2003,9(6):401-405
A 74-year-old man with combined valvular disease with a recent cerebral infarction was admitted. While undergoing thorough examination for valvular disease, absent right superior vena cava (RSVC) and persistent left superior vena cava (PLSVC) were recognized. Chest X-ray film suggested a right arch protrusion, and CT and venogram confirmed the diagnosis. During surgery, replacement of the mitral and aortic valves and annuloplasty of the tricuspid valve were performed. A blood draining cannula was inserted in retrograde fashion from the coronary sinus into the PLSVC, without any difficulties in the tricuspid valve repair. Due to bradycardic atrial fibrillation, we believed that it would be difficult to insert an endocardial electrode postoperatively, hence myocardial electrode was placed in the right ventricular wall. Absent RSVC combined with PLSVC is very rare, and a patient who underwent combined valve surgery with this rare anatomical abnormality is herein presented. 相似文献
76.
Akihiro Hosaka M.D. Tetsuro Miyata M.D. Hiroshi Shigematsu M.D. Jun-o Deguchi M.D. Hideo Kimura M.D. Hirokazu Nagawa M.D. Osamu Sato M.D. Takehiko Sakimoto M.D. Tomoyuki Mochizuki M.D. 《Journal of gastrointestinal surgery》2006,10(4):583-585
The vascular type of Ehlers-Danlos syndrome is a genetic disorder of connective tissue and is frequently associated with catastrophic
arterial complications. Its surgical treatment is extremely difficult because of the fragility of vessels. This article describes
three patients with vascular type of Ehlers-Danlos syndrome who developed mesenteric hemorrhage due to spontaneous arterial
rupture. The clinical and molecular characteristics of the disease are briefly reviewed. 相似文献
77.
Shigeru Abe Yuichi Sato Shigeharu Inoue Hiroko Ishibashi Naho Maruyama Toshio Takizawa Haruyuki Oshima Hideyo Yamaguchi 《Nippon Ishinkin Gakkai Zasshi》2003,44(4):285-291
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis. 相似文献
78.
S Iwata Y Sato Y Kusumoto H Shiro H Akita S Nanri T Oikawa M Osano K Sunakawa 《The Japanese journal of antibiotics》1986,39(9):2407-2420
The effect of cefotiam (CTM) on neonates and premature infants was examined in basic and clinical studies. Minimum inhibitory concentrations of CTM against 190 clinically isolated strains kept by this department were investigated. This drug was found to have a strong antibacterial effect against Escherichia coli, Klebsiella spp., Proteus mirabilis and Streptococcus agalactiae, Staphylococcus aureus and Staphylococcus epidermidis, although some strains were resistant. The CTM was given to 0-3, 4-7, and greater than or equal to 8 day-old premature infants and neonates by intravenous injection at the dose of 20 mg/kg, and we studied changes in serum CTM levels over time. Mean serum CTM levels were 62.3 micrograms/ml at 15 minutes and 16.4 micrograms/ml at 6 hours after the injection, with the half-life of 3.6 hours, for the 0-3 day-old premature infants. They were 38.5 micrograms/ml at 15 minutes and 10.1 micrograms/ml at 6 hours, with the half-life of 2.9 hours, for the 0-3 day-old neonates. Those levels were 22.5 micrograms/ml at 15 minutes and 2.9 micrograms/ml at 6 hours, with the half-life of 1.9 hours, for the 4-7 day-old neonates, and 51.8 micrograms/ml at 15 minutes and 1.0 micrograms/ml at 6 hours, with the half-life of 1.1 hours, for the greater than or equal to 8 day-old neonates. The CTM was given to 0-3 and greater than or equal to 8 day-old premature infants and neonates by 1-hour intravenous drip infusion at the dose of 20 mg/kg, and changes in serum CTM levels after the infusion were followed. The 0-3 day-old premature infant (there was only one subject) had a peak serum CTM level of 21.0 micrograms/ml 1 hour after the start of the infusion (that is, at the time of its completion), with the level decreased to 8.6 micrograms/ml at 7 hours and the half-life was 5.4 hours. The mean peak serum CTM level in 0-3 day-old neonates were 36.7 micrograms/ml at 1 hour, which decreased to a mean of 7.0 micrograms/ml at 7 hours; the half-life was 2.3 hours.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
79.
80.