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1.
Endorectal surface coil MR imaging of prostatic carcinoma with the inversion-recovery sequence 总被引:1,自引:0,他引:1
F Parivar V Rajanayagam V Waluch R T Eto L W Jones B D Ross 《Journal of magnetic resonance imaging : JMRI》1991,1(6):657-664
The value of inversion-recovery (IR) sequences in the diagnosis and staging of prostatic carcinoma with magnetic resonance (MR) imaging was studied. Twenty-six patients with carcinoma of the prostate were imaged at 1.5 T with an endorectal surface coil and with a variety of IR sequences and a set of spin-echo (SE) sequences for comparison. Ex vivo prostate specimens were imaged again at the same field strength. The two images were correlated with histologic sections. Cancer was identified with MR imaging in 96% of patients. Of the tumors more than 4 mm in diameter, 87% were identified on T2-weighted SE images, whereas only 26% were identified on IR images. However, IR images may be more useful in local staging of carcinoma. Gross capsular infiltration was present in only two patients; however, it was detectable (and excluded in five other patients) by means of IR images. It was not detectable on SE images. The high quality of images obtained with the endorectal coil was confirmed. The authors conclude that addition of the IR sequence to MR imaging with the endorectal coil may improve the usefulness of this examination. 相似文献
2.
Takashi Akasaki Yusuke Ohya Junya Kuroda Kimika Eto Isao Abe Hideki Sumimoto Mitsuo Iida 《Hypertension research》2006,29(10):813-820
Although vascular cells express multiple members of the Nox family of nicotinamide adenine dinucleotide phosphate (NAD(P)H) oxidase, including gp91phox, Nox1, and Nox4, the reasons for the different expressions and specific roles of these members in vascular injury in chronic hypertension have remained unclear. Thus, we quantified the mRNA expressions of these NAD(P)H oxidase components by real-time polymerase chain reaction and evaluated superoxide production and morphological changes in the aortas of 32-week-old stroke-prone spontaneously hypertensive rats (SHRSP) and age-matched Wistar Kyoto rats (WKY). The aortic media of SHRSP had an approximately 2.5-fold greater level of Nox4 mRNA and an approximately 10-fold greater level of Nox1 mRNA than WKY. The mRNA expressions of gp91phox and p22phox in SHRSP and WKY were comparable. SHRSP were treated from 24 weeks of age for 8 weeks with either high or low doses of candesartan (4 mg/kg/day or 0.2 mg/kg/day), or a combination of hydralazine (30 mg/kg/day) and hydrochlorothiazide (4.5 mg/kg/day). The high-dose candesartan or the hydralazine plus hydrochlorothiazide decreased the blood pressure of SHRSP to that of WKY, whereas the low-dose candesartan exerted no significant antihypertensive action. Media thickening and fibrosis, as well as the increased production of superoxide in SHRSP, were nearly normalized with high-dose candesartan and partially corrected with low-dose candesartan or hydralazine plus hydrochlorothiazide. These changes by antihypertensive treatment paralleled the decrease in mRNA expression of Nox4 and Nox1. These results suggest that blood pressure and angiotensin II type 1 receptor activation are involved in the up-regulation of Nox1 and Nox4 expression, which could contribute to vascular injury during chronic hypertension. 相似文献
3.
Goichi Yotsumoto Koki Tanaka Naoki Ishizaki Akira Ikoma Sumihiro Kawashima Akira Taira 《Surgery today》1997,27(7):657-660
We report herein a case of spontaneous subcapsular hepatic hemorrhage which occurred in a 33-year-old woman 1 day after she
had been delivered of her second child by cesarean section following an uneventful pregnancy. She complained of right upper
quadrant pain on the 1st postoperative day, and computed tomography (CT) showed subcapsular low-density masses in both liver
lobes, while extravasation was demonstrated by CO2 intraarterial digital subtraction angiography (IADSA). The hemorrhage was successfully controlled by transcatheter arterial
embolization (TAE). However, on the 3rd day after TAE, an exploratory laparotomy was performed to establish an exact diagnosis
to explain the persistent abdominal pain and abnormal liver function tests. Subcapsular hematomas in both lobes were confirmed
and no visible laceration was present. The patient recovered gradually by spontaneous absorption of the hematomas and was
discharged on the 22nd postoperative day. Spontaneous hepatic hemorrhage associated with pregnancy is a very rare complication,
and establishing a correct diagnosis and initiating appropriate therapy are essential for this life-threatening disease. 相似文献
4.
Age- and sex-related differences in the nerve growth factor distribution in the rat brain. 总被引:2,自引:0,他引:2
Levels of the nerve growth factor (NGF) have been measured in various brain regions of young and aged male and female rats of Wistar strain by means of a highly sensitive two-site enzyme immunoassay system for beta-NGF. Among the ten regions examined, the amount of NGF per wet weight of tissue was found to be highest in the hippocampus, irrespective of the sex and age. The NGF concentration in the hippocampus of female rats at 3 months of age was comparable to that of same aged males. Further, there was no significant difference in the NGF levels of the hippocampus between young and age males. However, the NGF level was significantly lower in aged females as compared to that in 3- or 4-month-old females, and hence the marked male-female difference was found in the NGF levels in aged Wistar rats. 相似文献
5.
Severe hypertension developed in a fifty-five year-old woman after surgical removal of a retroperitoneal tumor, when the renal artery was injured. Renal arteriography after the surgery demonstrated a segmental infarction of the right kidney. A close relationship between activation of the renin-angiotensin system and the development of severe hypertension was observed. Satisfactory control of blood pressure concomitant with reduction of plasma renin activity was achieved by a combination of an angiotensin-converting anzyme inhibitor, beta-blocking agent, and calcium-entry blocker. The mechanism of activation of the renin-angiotensin system in renal infarction is discussed. 相似文献
6.
7.
Shuichiro Uchiyama Kazuo Chijiiwa Masahide Hiyoshi Motoaki Nagano Jiro Ohuchida Koki Nagaike Masahiro Kai Kazuhiro Kondo 《Journal of gastrointestinal surgery》2007,11(11):1570-1572
Mucin-producing tumor in the bile duct is referred to clinically as mucin-producing bile duct tumor (MPBT). Intraductal papillary
neoplasm of the biliary tract that resembles an intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a rare category
of MPBT and is not well characterized. We, herein, report a case of MPBT of the caudate lobe of the liver that showed papillary
growth and communicated with the bile duct of the caudate lobe and protruded into the common hepatic duct. Histologically,
MPBT cells showed papillary overgrowth with abundant mucinous secretions, resembling an IPMN of the pancreas. The MPBT cells
showed the same immunostaining pattern as that of cells from IPMN of the pancreas. 相似文献
8.
A case of a rare anomaly of the common bile duct associated with an abnormal arrangement of the pancreaticobiliary ductal union 总被引:1,自引:0,他引:1
L E Loria K Yamamoto T Eto T Tomioka T Miyamoto N Mochinaga R Tsuchiya 《The Japanese journal of surgery》1988,18(6):718-724
A 39 year-old Japanese female patient with a duplication of the distal portion of the common bile duct is presented herein. Moreover, an abnormal arrangement of the pancreaticobiliary ductal union, congenital biliary dilatation and carcinoma of the gallbladder were all demonstrated by cholangiographic and endoscopical studies. The patient underwent radical surgery for advanced adenosquamous carcinoma of the gallbladder, and her postoperative course was satisfactory. A reflux of pancreatic juice into the bile duct was demonstrated, but it was eliminated and considered to be a contributory etiologic factor of the gallbladder carcinoma. 相似文献
9.
Hikaru Tanaka Naofumi Uesato Koki Shigenobu 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(4):391-397
Chronotropic and inotropic effects of histamine were examined in isolated atrial and ventricular preparations from embryonic and hatched chicken hearts. Histamine produced positive chronotropic and inotropic responses both in embryonic and hatched hearts. The responses to histamine in middle embryonic myocardia, which were observed in the micromolar range, were antagonized by H2 antagonists but not by H1, H3 antagonists and propranolol. Isobutylmethylxantine, an inhibitor of phosphodiesterase, produced a leftward shift of the concentration-response curve for the chronotropic effect of histamine in the embryo. The responses to histamine in myocardia from hatched chicks, which were observed in the milimolar range, appeared concurrently with the responses to tyramine during development and were antagonized by beta adrenoceptor antagonists but not by any of the histamine antagonists. The positive inotropic response to histamine in hatched ventricular preparations were greatly attenuated by reserpine pretreatment or in the presence of desipramine. Thus, we demonstrated that exogenously applied histamine produces positive chronotropic and inotropic responses in developing chicken hearts and that the mechanisms are different between embryonic and hatched chicks: direct action on H2 receptors in the embryonic heart and release of norepinephrine from sympathetic nerve terminals in hatched hearts. 相似文献
10.
Opioid supplements are often required in total intravenous anesthesia (TIVA). Most ϰ-opiate receptors are found in the spinal
cord, wherea μ-opiate receptors are widespread throughout the brain and spinal cord. Buprenorphine has a strong μ-action with
a minute ϰ-action, while eptazocine stimulates ϰ-receptors only. From these, epidural eptazocine is expected to exert strong
spinal analgesia by ϰ-stimulation without μ-action, which produces circulatory and respiratory depression. Therefore, the
clinical effects of epidural opioids on circulation, respiration, and analgesia were compared. Continuous epidural administration
of eptazocine or buprenorphine was combined with TIVA in patients scheduled for elective abdominal surgery. Epidural opioid
administration was continued throughout and for 72h after anesthesia. A significant analgesic effect (P<0.01) of epidural eptazocine without circulatory and respiratory depression was observed. With epidural buprenorphine, circulatory
and respiratory depression during and immediately after anesthesia were significant (P<0.05). These results suggest that medullary μ-stimulation by an epidural opioid induces circulatory (hypervagotonicity and
hypervagosensitivity) and respiratory depression, while ϰ-stimulation produces only minimal effects on circulatory and respiratory
systems. 相似文献