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41.
BACKGROUND: This study assessed the calcium-activating mechanisms mediating glomerular arteriolar constriction by angiotensin II (Ang II). METHODS: Immunohistochemical and physiological studies were carried out, using antibody against transient receptor potential (TRP)-1 and an isolated perfused kidney model. RESULTS: Immunohistochemical experiments demonstrated that TRP-1 proteins were transcribed on both afferent and efferent arteriolar myocytes. In the first series of physiological experiments, Ang II (0.3 nmol/L) considerably constricted afferent (20.2 +/- 0.9 to 14.9 +/- 0.7 microm) and efferent arterioles (18.4 +/- 0.7 to 14.0 +/- 0.7 microm). The addition of nifedipine (1 micromol/L) restored decrements in afferent (to 20.0 +/- 0.8 microm) but not efferent arteriolar diameters. Further administration of SKF-96365 (100 micromol/L), a TRP channel blocker, reversed efferent arteriolar constriction (to 16.2 +/- 0.8 micromol/L). In the second group, although 2-aminoethoxydiphenyl borate (100 micromol/L), an inhibitor of inositol trisphosphate-induced calcium release (IP3CR), did not alter glomerular arteriolar diameters, it prevented Ang II-induced afferent arteriolar constriction and attenuated efferent arteriolar constriction (18.8 +/- 0.8 to 16.9 +/- microm). Subsequent removal of extracellular calcium abolished residual efferent arteriolar constriction (to 19.1 +/- 0.8 microm). CONCLUSIONS: Our data provide evidence that Ang II elicits IP3CR, possibly inducing a cellular response that activates voltage-dependent calcium channels on afferent arterioles. The present results suggest that Ang II-induced efferent arteriolar constriction involves IP3CR and calcium influx sensitive to SKF-96365.  相似文献   
42.
Background/Purpose: Given that the prognosis of patients with hepatocellular carcinoma (HCC) complicating severe cirrhosis remains uncertain, particularly with regard to various therapeutic strategies, we have evaluated the prognosis in a series of patients with homogeneous diagnostic and therapeutic histories. Methods: From 1990 to 1998, 411 consecutive HCC patients associated with Child class B and class C cirrhosis who did not have lymph node or distant metastasis were treated by partial hepatectomy (PH; n = 48), percutaneous ethanol injection (PEI; n = 105), transcatheter arterial chemoembolization (TACE; n = 189), chemotherapy, or supportive care (chemo/supportive; n = 69). Univariate survival curves were estimated. The Cox model, stratified by the treatment groups, was used for multivariate analysis. Results: As of January 1999, 305 patients (74.2%) had died. Overall median survival was 23.4 months. There were statistically significant differences between the survival times of patients receiving PH or PEI and TACE, as compared with those receiving chemo/supportive care. According to multivariate analysis, the independent predictive survival factors were: albumin level (≥3.0 g/dl), esophageal varices (i.e., absence), tumor size (≤3.0 cm), tumor number (solitary), and α-fetoprotein (AFP) level (<400 ng/ml). According to the total number of risk factors and the median survival, all patients were divided into four subgroups. For the score 0 group (no risk factor group), 3- and 5-year survival rates were 83.1% and 68.0% for PH, and 87.5% and 62.3% for PEI, respectively. In the score 1–2 group (one or two risk factors), survival rates at 3 and 5 years were 53.1% and 40.3% for PH, 54.8% and 33.2% for PEI, and 35.4% and 22.8% for TACE, respectively. For patients with a score of 3 or more, there were no differences among the treatment groups, excluding those with chemo/supportive care. Conclusions: These findings indicate that, in HCC patients with complicating Child B and C cirrhosis, PEI and PH should be considered first for subgroups of patients with scores (risk factors) of 0–2, as an acceptable survival rate was obtained in such patients. Therefore, the advantages and disadvantages of these therapies regarding tumor size and location should be counterbalanced. In patients with a score of 3 or more, TACE, when possible, could be a first choice because of its applicability and its adjuvant nature with respect to other therapies such as liver transplantation. Received: February 6, 2002 / Accepted: May 22, 2002 Offprint requests to: S. Ueno  相似文献   
43.

Background  

This study was designed to determine whether gene methylation is a novel diagnostic marker for micrometastasis to the lymph nodes (LNs) in gastric cancer.  相似文献   
44.
The fear of serious complications, such as a necrotic conduit caused by an impaired blood circulation can arise when replacing the esophagus with an intestinal conduit. The aim of this paper is to present effective superdrainage of an intestinal conduit using an inferior mesenteric vein (IMV) interposition graft. In 2008, we performed superdrainage of the ileocolic vein to the internal jugular vein interposed by an IMV graft in replacing the esophagus with the right hemicolon for advanced thoracic esophageal cancer in three patients with a synchronous gastric cancer or a previous gastrectomy. No leakage at the enteric anastomoses occurred. Neither ischemic lesions in these intestinal conduits nor complications caused by harvesting an IMV graft were observed. Superdrainage of the ileocolic vein to the internal jugular vein interposed by an IMV graft effectively improves the blood circulation in intestinal conduits brought up to the neck as an esophageal replacement.  相似文献   
45.
Background: Previous studies documented that near-infrared spectroscopy values were affected by factors related to optical path length, such as hemoglobin concentration, the differential path length factor, skull thickness (t-skull), and the area of the cerebrospinal fluid layer (a-CSFL). Lately, the NIRO-100 (Hamamatsu Photonics, Hamamatsu, Japan) has provided a tissue oxygen index (TOI) that theoretically is not supposed to be affected by optical path length. Therefore, the authors hypothesized that TOI is not influenced by the above-described individual factors.

Methods: Cardiac surgical or neurosurgical 103 patients (65 men and 39 women; aged 63 +/- 14 yr) were studied. TOI and regional cerebral oxygen saturation (rSO2) (INVOS 4100; Somanetics, Troy, MI) were measured sequentially on patients in a resting state. The t-skull and a-CSFL were calculated using computed tomographic image slices of the head corresponding with the position of near-infrared spectroscopy sensors. The effects of these two factors, hemoglobin concentration and mean arterial pressure, on TOI and rSO2 values were evaluated by linear regression analysis.

Results: Simple linear regression analysis showed that mean arterial pressure (r = 0.27, P = 0.008), t-skull (r = 0.22, P = 0.034), a-CSFL (0.26, P = 0.012), and hemoglobin concentration (r = 0.42, P < 0.0001) were significant determinants of rSO2. Multiple linear regression analysis showed that hemoglobin concentration (r = 0.34, P < 0.001), a-CSFL (r = -0.252, P = 0.012), and t-skull (r = 0.22, P = 0.037) were significant determinants of rSO2. On the other hand, simple and multiple linear regression analysis showed that there was no significant determinant of TOI.  相似文献   

46.
Hepatopulmonary syndrome (HPS) is a serious complication of terminal liver disease, which manifests as severe hypoxia without any pulmonary anatomic or functional causes. The precise indications for liver transplantation in patients with severe HPS also remain unclear. A 49-year old woman was referred to our department for investigation and management of liver cirrhosis with severe hypoxia (PaO2, 38 mmHg). A pulmonary perfusion scintigram showed an intrapulmonary shunt ratio of 40%, confirming a diagnosis of severe HPS. She underwent living donor liver transplantation using a right lobe graft donated by her 27-yearold daughter. Her post-transplant graft function was excellent, and her oxygenation recovered slowly but steadily. She was discharged from hospital on posttransplant day 39 with an SpO2 of 94% under 3 l/min of O2, delivered nasally. Despite the severity of the HPS, her postoperative recovery was smooth after the liver transplant.  相似文献   
47.
Twelve years after receiving a renal transplant, a 50-year-old woman developed asthmatic symptoms. Chest CT revealed a descending thoracic aortic aneurysm. She had undergone percutaneous coronary intervention to treat the left anterior descending artery 10 years earlier. Coronary artery angiography revealed restenosis of the left anterior descending artery (99%, #6 in-stent). Because cardiopulmonary bypass may cause problems for transplanted kidney, we performed off-pump coronary artery bypass grafting (left internal thoracic artery to left anterior descending artery) and thoracic endovascular graft placement to treat the aortic aneurysm. Considering that the artery of the transplanted kidney was attached to the right iliac artery, and then the left common femoral artery was selected as the access root for GORE TAG(?) endografts (34 × 200 and 34 × 150 mm) (stentgrafts were deployed for the descending aortic artery). Postoperative angiography showed a patent bypass graft. Postoperative CT confirmed the absence of endoleaks. The postoperative course was uneventful, and she was discharged without complications. Ischemic heart disease and descending thoracic aortic aneurysm in recipients of kidney transplants can be treated using off-pump coronary bypass grafting and thoracic endovascular graft placement. The transplanted kidney was protected without using cardiopulmonary bypass (CPB).  相似文献   
48.
We assessed the potential clinical utility of levels of p53-specific antibodies as a novel serum biomarker of prostate cancer that could be used in conjunction with level of PSA. Material and methods Serum levels of p53-specific antibodies in patients with relapsed, newly diagnosed prostate cancer and in patients with benign prostate hyperplasia were quantified by an enzyme-linked immunoabsorbent assay. Result There was no significant difference (P = 0.96) between the serum levels of p53-specific antibodies in patients with newly diagnosed prostate cancer and with benign prostatic hyperplasia. In the newly diagnosed prostate cancer group, stage T1c (n = 8) showed the lowest p53-specific antibody level. However, the difference between T1c group and benign prostatic hyperplasia group was not significant (P = 0.686). The relapsed cancer group tended to have low levels of the antibodies, and, there was no significant difference between the relapsed prostate cancer group and the benign prostatic hyperplasia group (P = 0.14). The serum levels of p53-specific antibodies in patients with metastatic and with localized prostate cancer showed no significant difference (P = 0.68). Conclusion The use of titers of p53-specific antibodies to make differential diagnosis between prostate cancer and benign prostatic hyperplasia might have no role, and the antibodies should not be used as a marker of prostate cancer by itself. Because our study is based on small number of patients, further studies are necessary before its absolute validity can be determined.  相似文献   
49.
BACKGROUND: Renal transplantation is a definitive therapeutic modality in end-stage renal disease (ESRD). Most ESRD patients in Japan experience dialysis prior to renal transplantation. The present study was undertaken to examine the usefulness of pre-emptive renal transplantation (PET). METHODS: Between 1987 and 1998, 255 renal transplantations were carried out by the authors. Among those consecutive cases, 10 were cases of PET. In nine pediatric cases, demographics, graft and patient survival, height growth and benefits from successful transplantation were studied and compared with age-matched dialyzed transplantation controls. RESULTS: All transplantation was living-related. There was a disparity of causes of ESRD between the two groups. In PET, acquired renal deterioration due to a congenital lower urinary tract disorder was the major cause. Graft and patient prognosis was favorable in both groups. Growth retardation in PET patients under 15 years of age was significantly less apparent at the time of transplantation and after 3 years compared to the control. The benefits from transplantation were different in the two groups. Most PET patients felt an improvement of their physical condition; however, all of the control patients felt that the major boon was the freedom from the restriction of the daily diet and time for dialysis. CONCLUSION: In pediatric renal transplantation, short-term preceding dialysis does not have a detrimental effect, but PET could benefit ESRD patients by maintaining their quality of life. Moreover, PET minimizes the production of renal dwarfism in prepubertal children. Thus, PET should be taken into consideration in the choice of renal replacement therapy.  相似文献   
50.
STUDY OBJECTIVE: To evaluate the safety and efficacy of small-bore, silastic drains for patients undergoing general thoracic surgery. PATIENTS AND METHODS: Twenty-five patients who received soft, small-bore, silastic drains were compared with 17 patients who received semi-rigid double lumen (DL) tubes retrospectively. RESULTS: The pain score was significantly lower in patients who received the silastic tubes in video-assisted thoracoscopic surgery (VATS) cases on postoperative days 5 and 6 , after continuous epidural analgesia had finished (P=0.018). No specific morbidity was seen in the patients who received silastic tubes. CONCLUSION: We considered that soft, small-bore silastic drains were just as effective as traditional DL tubes, but caused less pain especially in VATS cases.  相似文献   
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