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排序方式: 共有1836条查询结果,搜索用时 15 毫秒
1.
Kazunori Aizawa Takeshi Hanaoka Hiroki Kasai Kaoru Kogashi Setsuo Kumazaki Jun Koyama Hiroshi Tsutsui Yoshikazu Yazaki Noboru Watanabe Osamu Kinoshita Uichi Ikeda 《Hypertension research》2006,29(2):123-128
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH. 相似文献
2.
Yukio Naya Toyofusa Tobe Takahito Suyama Kazuhiro Araki Akira Komiya Hiroyoshi Suzuki Tatsuo Igarashi Tomohiko Ichikawa 《International journal of urology》2007,14(1):17-20
OBJECTIVES: Laparoscopic surgery for kidney treatment is a common procedure. However, the efficacy of this procedure in patients with several comorbidities has not been well investigated. We conducted a retrospective comparison of results of laparoscopic surgery between patients with several comorbidities and patients with no comorbidity to access the efficacy and safety of this procedure. METHODS: The subjects were 20 patients with three or more comorbidities (group A) and 46 patients with less than three comorbidities (group B). These 66 patients were 48 men and 18 women with a mean age of 62.3 years (age range, 24-83 years). The data from these two groups were compared for American Society of Anesthesiology (ASA) physical status score, previous surgical history, duration of surgery, estimated blood loss, tumor size, complications during and after surgery, conversion rates, time to oral intake, and length of hospital stay. RESULTS: The initial ASA score and age were significantly higher for the patients with comorbidities (P < 0.0001, P = 0.0008, respectively). All other variables before, during, and after surgery were similar for both laparoscopic groups. However, the incidence of atelectasis of laparoscopy was higher than that of open surgery. CONCLUSIONS: Laparoscopic nephrectomy for patients with comorbidities is safe and minimally invasive. Further investigation to prevent atelectasis is necessary. 相似文献
3.
Takahito Adachi Makoto Takeuchi Satomi Uno Motohisa Kato Kiichi Miya Shigetoyo Saji 《Surgery today》1997,27(12):1144-1149
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor
activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive
activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced
by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA
synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with
serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted
DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth
factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide
(MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate
dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced
in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment
of liver failure. 相似文献
4.
S Sato T Iiyama R Hata H Tomomasa H T Iizumi T Yazaki T Umeda H Amemiya H Muramatsu 《Nihon Jinzo Gakkai shi》1992,34(6):711-715
A 59-year-old male was admitted to our clinic for further examination of the calcified renal cyst discovered incidentally on medical workup elsewhere. CT showed a left renal cyst associated with calcification. Ultrasound-guided puncture of the renal cyst was not successful because of thickness of the cystic wall. Renal angiography showed hypervascularity of the cystic wall. Association of renal cell carcinoma could not be ruled out, therefore the exploration was performed. Histological examination revealed benign renal cyst with calcification. A 27-year-old male presented with the chief complaint of left flank pain. Following examinations by US, CT and MRI, a renal cyst associated with renal cell carcinoma was highly suspected. Subsequent exploration revealed cluster of cysts with a yellowish lesion a few mm in diameter. Frozen section revealed no malignancy, and cystic fluid was not hemorrhagic. Therefore as many cystic walls as possible were removed without nephrectomy. Histological examination of the permanent specimen revealed renal cell carcinoma. Renal cyst associated with renal cell carcinoma was regarded as rare clinical entity, but such cases are reported in increasing number in recent years. We report such cases and review the pertinent literature in this paper. 相似文献
5.
Ouabain has recently been reported to be an endogenous Na, K-ATPase inhibitor. To evaluate whether it exerts hypertensive action itself or amplifies the hypertensive action of small doses of mineralocorticoids, 5 mg deoxycorticosterone acetate (DOCA), 1 mg ouabain, or a combination of both were injected into mononephrectomized rats weekly for 6 weeks, and changes in blood pressure were evaluated. The blood pressures of control, DOCA-treated, ouabain-treated, and the combination treatment group at the sixth week were 138 +/- 3 (SE), 160 +/- 6, 144 +/- 6, and 201 +/- 14 mmHg, respectively. The blood pressure of rats given DOCA or ouabain alone was not significantly different from that of controls. In contrast, the blood pressure of rats given the combination of DOCA and ouabain was significantly higher than that of control rats and those given DOCA or ouabain separately. Cardionephromegaly and histopathological changes found in rats given the combination of DOCA and ouabain were consistent with the effects of an elevation of blood pressure. Further evaluation revealed that the amplification effect of ouabain on the hypertensive action of DOCA was dose dependent, with the minimum dose that caused the amplification effect being 0.25 mg/week. These results indicate that ouabain, although devoid of hypertensive action itself, amplifies the hypertensive action of small doses of DOCA and can cause a hypertensive state similar to that induced by larger doses of DOCA. It is inferred that the amplification effect of ouabain on mineralocorticoids is important in the genesis of hypertension. 相似文献
6.
Stem cells of the adult kidney: where are you from? 总被引:1,自引:0,他引:1
Takahito Ito 《Nephrology, dialysis, transplantation》2003,18(4):641-644
7.
Tsukasa Tsunoda Toshifumi Eto Takahito Tsurifune Shigeki Tokunaga Tatsuhiro Ishii Koichi Motojima Teiji Matsumoto Tohru Segawa Kazuhide Ura Hiroshi Fukui 《Pathology international》1991,41(10):763-770
A solid and cystic tumor (SCT) was located at the head of the pancreas in a 43-year-old Japanese male, and pancreatoduodenectomy was performed on the suspicion of papillary carcinoma or cystadenocarcinoma of the pancreas. The lesion, which measured 4.5 X 4.5 X 4.0 cm, was clearly demarcated by connective tissue. The cut surface showed solid grayish-white areas with central cystic degenerative changes. The solid areas consisted of small round cells proliferating in a small solid or a pseudopapillary pattern. The tumor cells partially invaded the surrounding normal pancreatic parenchyma. Immunohistochemical studies revealed positive staining for alpha-1-antitrypsin and neuron-specific enolase, but no staining for known pancreatic hormones. Moreover, ultrastructural studies showed the absence of zymogen granules and the presence of anullate lamellae and neurosecretory granules. On the basis of these findings, a diagnosis of SCT of the pancreas was established. In order to clarify the histogenesis and biological behavior of the tumor, it is necessary to accumulate and analyze similar cases, an endeavor which in turn will contribute to the successful management of this disease. Acta Pathol Jpn 41: 763-770, 1991. 相似文献
8.
Spreading of cells on a solution surface could visualize vesicular stomatitis virus nucleocapsids and virions in infected cells easily and clearly without the need for any purification. Characteristic structures observed by the spreading of the infected cells are described and discussed. 相似文献
9.
C-reactive protein levels in the serum of asthmatic patients. 总被引:1,自引:0,他引:1
Miyoshi Fujita Shigeharu Ueki Wataru Ito Takahito Chiba Masahide Takeda Norihiro Saito Hiroyuki Kayaba Junichi Chihara 《Annals of allergy, asthma & immunology》2007,99(1):48-53
BACKGROUND: Asthma is a chronic airway inflammatory disease caused by immune cells such as T lymphocytes and eosinophils. Recently, highly sensitive C-reactive protein (hs-CRP) assays have become available for detecting small changes in CRP levels within the reference range, allowing for the evaluation of clinical inflammation. OBJECTIVE: To investigate the relationship between hs-CRP levels and bronchial asthma. METHODS: We collected blood samples from 109 patients with bronchial asthma, with or without attacks, and measured serum eosinophil cationic protein levels, pulmonary function, and serum CRP levels using an hs-CRP assay. RESULTS: Mean serum hs-CRP levels were significantly higher in patients without attacks (0.473 mg/L) and with attacks (0.908 mg/L) (P < .001 for both) than in controls (0.262 mg/L). Serum hs-CRP levels were inversely correlated with forced expiratory volume in 1 second/forced vital capacity in asthmatic patients (r = -0.4915; P < .01). CONCLUSION: Serum hs-CRP levels may be related to the state of asthma exacerbation and allergic inflammation. 相似文献
10.
Yamamoto H Yazaki K Inoue K 《Journal of chromatography. B, Biomedical sciences and applications》2000,738(1):3-15
A high-performance liquid chromatography (HPLC) analysis system based on a water-acetonitrile gradient program was established for simultaneous quantification of shikimate-derived secondary metabolites in cultured cells of Lithospermum erythrorhizon. The cells cultured in pigment production medium (M-9) are capable of producing five highly hydrophilic compounds such as p-hydroxybenzoic acid-O-glucoside and lithospermic acid B, as well as eleven lipophilic compounds including echinofuran B and acetylshikonin. In addition to the wide polarities of those compounds, many of them are unstable under light, dryness, oxygen and heating. Thus, a new extraction procedure for all these compounds was also established by use of ultrasonication under ice-water chilling with MeOH as the solvent. This procedure was applied to the quantitative analyses of these compounds in cell cultures and hairy root cultures of Lithospermum, and in the intact plants as well. 相似文献