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91.
Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts.  相似文献   
92.
93.
The use of cryopreserved aortic allografts in cardiovascular surgery is widespread and has resulted in excellent outcomes. However, it is controversial whether cryopreservation suppresses the antigenicity of tissue. We designed experimental models to study whether the cryopreservation process alters antigenicity in comparison with that found in fresh and glutaraldehyde treated tissues. Fresh, cryopreserved, and glutaraldehyde treated thoracic aorta from Brown Norway rats were subcutaneously implanted into Lewis rats. Inflammatory cells infiltrating around the grafts were measured on days 7, 14, 28, and 56 after implantation. The glutaraldehyde treated grafts showed significantly less infiltration than the fresh or cryopreserved grafts (p < 0.005). No significant difference was detected between the fresh and cryopreserved grafts. Another study examined the effect of modifications of the aortic allograft on subsequent allogeneic skin graft antigenicity. Subcutaneous implantation of fresh, cryopreserved, and glutaraldehyde treated aortic grafts from Brown Norway into Lewis rats resulted in subsequent skin graft rejection at 4.4+/-0.7, 5.1+/-0.8, and 6.6+/-2.1 days, respectively. There was no significant difference between the fresh and cryopreserved groups; whereas skin grafts in the glutaraldehyde group survived longer than those in the cryopreserved group. These results indicate that cryopreservation had no significant influence on antigenic suppression of arterial allografts.  相似文献   
94.
PROBLEM: The preconceptional natural-killer cell (NK) activity predicts subsequent miscarriage among women with unexplained recurrent spontaneous abortion (RSA). Psycho-neuro-immuno-endocrine network has recently been proposed as a mechanism for abortions. We therefore examined which psychosocial factors influenced the NK activity among women with RSA. METHOD OF STUDY: We measured the preconceptional NK activity of 61 women with a history two consecutive unexplained first-trimester miscarriages and no live births. We also administered semi-structured interviews and a battery of self-report questionnaires to assess their social support, personality, self-esteem and psychiatric symptoms. RESULTS: The preconceptional NK activity was negatively correlated with the women's neuroticism personality trait (r= -0.32, P = 0.01) and current depressive symptoms (r = -0.26, P= 0.05), and positively correlated with their self-esteem (r = 0.34, P = 0.01). CONCLUSIONS: In addition to several substances such as transforming-growth-factor beta and granulocyte-macrophase colony-stimulating factor, we found that low neuroticism, low depression scale score and high self-esteem contributed to high NK activity among women with RSA.  相似文献   
95.
PROBLEM: Hepatocyte growth factor (HGF) exists abundantly in seminal plasma and its receptor, c-met, is expressed on spermatozoa. Considering its motogenic activity, we speculated that HGF might affect the movement ability of spermatozoa. METHODS: Recombinant HGF was added to washed spermatozoa and their movements were analyzed using a computer-assisted sperm analyzer. The concentration of HGF in the seminal plasma of infertile patients (n = 83) was measured by ELISA, and the data were compared with their hormonal profile and semen parameters. RESULTS: The HGF physiological concentration (1 ng/mL) maintained the motility of sperm after a long incubation, though the difference was not statistically significant. Recombinant HGF did not affect the linearity or frequency of movement, which suggested that it does not evoke the hyperactivation of spermatozoa. The concentration of HGF in seminal plasma did not correlate with any clinical parameter of the patients. CONCLUSIONS: These findings contradict the theory that HGF controls the movement of sperm. The main role of this axis in the male reproductive system might be maturation in the epididymis.  相似文献   
96.
The authors observed a variation of the inferior mesenteric artery, which arose from the superior mesenteric artery, in a 69-year-old Japanese male cadaver during dissection in 1984. In this case, no rudiment of the ordinary inferior mesenteric artery could be found on the abdominal aorta. There are few reports of this variation, and an extensive search of the available literature revealed only four cases, including two in Japan. Such a variation had been somewhat inadequately described as an "absence of the inferior mesenteric artery" in the previous reports, but we avoided this terminology, because all of the cases possessed an artery, which, though arising from the superior mesenteric artery instead of the abdominal aorta, had the same branches as a normal inferior mesenteric artery. Consistent with findings observed in the previous cases, the unusual inferior mesenteric artery arose as the first branch of the superior mesenteric artery, with the common trunk of both mesenteric arteries originating from the abdominal aorta at a level at which an ordinary superior mesenteric artery would arise. It is for this reason that we did not adopt another acceptable name, that is, "the common mesenteric artery," for this variation. The variation can be explained as the result of an unusual development of the embryonic artery system, which comprises a number of ventral splanchnic arteries interconnected by longitudinal anastomotic channels to supply the primitive digestive tube.  相似文献   
97.
Two cases of papillary type of C cell carcinoma of the thyroid were reported. They showed papillary arrangement with Abrovascular stalk in properly Axed tissues. Histochemically argyrophil reaction was positive in the cytoplasm and amyloid deposited in the stroma. Ultrastructurally secretory granules were found in their cytoplasm. The papillary type is not an artifact but one of the histologic variations of this carcinoma. ACTA PATH. SAP. 29: 653–659, 1979.  相似文献   
98.
The 4-aminopyridine (4AP) sensitive outward current of enzymatically dispersed single smooth muscle cells of the rabbit main pulmonary artery were investigated using the voltage clamp method. When the cell was exposed to physiological salt solution (PSS) in the bath and high K+ in the pipette no inward current was generated by depolarization of the membrane, but when 4AP was present in the bath or when Cs+ with tetraethylammonium+ (Cs+-TEA+) in the pipette, an inward current was generated. This current was enhanced by Ba2+ or high Ca2+ and was blocked by inorganic or organic Ca2+ channel blockers.The outward current was partly inhibited by the Ca2+ channel blockers, Ca2+-free or Mn2+ containing solution. The residual outward current was blocked by external application of 10 mM 4AP, whereas it was inhibited by half with 100 mM TEA+. To investigate further natures of 4AP sensitive outward current, the following experiments were done in the bath solution containing 2.5 mM Mn2+. The reversal potential of this outward current, estimated from the tail current, remained the same in Na+-deficient solution, but shifted to near the K+-equilibrium potential in Cl deficient solution. Thus, the main current carrier for the outward current seems to be K+, but Cl may participate to some extent. The amplitude of the outward current decreased slowly. However, the reversal potential was not changed, suggesting the reduction in amplitude of the outward current was not due to the accumulation of K+ on the outer surface of the membrane. As 4AP inhibited the outward current to a greater extent at lower than higher membrane potential levels, 4AP bound to the channel may be dislodged at higher levels. When pH of the bath solution was modified from 7.3 to 8.0, inhibitory actions of 4AP were enhanced (pKa value of 4AP=9.17). Thus, a non-ionized form of 4AP may act as a channel blocker. We conclude that in smooth muscle cells of the pulmonary artery, lack of an action potential in physiological solution may partly be due to a small inward current as well as a large contribution of the 4AP sensitive outward current.  相似文献   
99.
Recently, cavitation on the surface of mechanical heart valves has been studied as a cause of fractures occurring in implanted mechanical heart valves. The cause of cavitation in mechanical heart valves was investigated using the 25 mm Medtronic Hall valve and the 23 mm Omnicarbon valve. Closing of these valves in the mitral position was simulated in an electrohydraulic totally artificial heart. Tests were conducted under physiologic pressures at heart rates from 60 to 100 beats per minute with cardiac outputs from 4.8 to 7.7 L/min. The disk closing motion was measured by a laser displacement sensor. A high-speed video camera was used to observe the cavitation bubbles in the mechanical heart valves. The maximum closing velocity of the Omnicarbon valve was faster than that of the Medtronic Hall valve. In both valves, the closing velocity of the leaflet, used as the cavitation threshold, was approximately 1.3-1.5 m/s. In the case of the Medtronic Hall valve, cavitation bubbles were generated by the squeeze flow and by the effects of the venturi and the water hammer. With the Omnicarbon valve, the cavitation bubbles were generated by the squeeze flow and the water hammer. The mechanism leading to the development of cavitation bubbles depended on the valve closing velocity and the valve stop geometry. Most of the cavitation bubbles were observed around the valve stop and were generated by the squeeze flow.  相似文献   
100.
An autopsy case of a 65-year-old male who died of hepatocellular carcinoma superimposed on liver cirrhosis complicated with systemic sarcoidosis is presented. No organ metastasis of hepatocellular carcinoma was found except for a minute tumor embolus in the left upper lobe of the lung. Involved organs by sarcoidosis were the lymph nodes, lungs, heart, liver and spleen, but its presence was not noticed before death. Its cardiac involvement coincide with his clinical symptom of exertional dyspnea and the ECG finding of A-V block.  相似文献   
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