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41.
PURPOSE: To examine value of prostate-speci fi c antigen (PSA) adjusted by prostate volume measured using transabdominal ultrasonography in prostate cancer detection among men with elevated PSA. METHODS: 238 men aged 79 years or younger with serum PSA levels of 2.0-20.0 ng/mL and normal digital rectal examination fi ndings were studied in terms of total and free PSA, prostate volumes with transrectal (TRUS) and transabdominal (TAUS) ultrasonography and transition zone volumes with TRUS prior to transrectal 10-core biopsy. In addition to sole PSA values and the free-to-total PSA ratio, volume-adjusted PSA values, PSA densities determined by TRUS (PSAD(TRUS)), and TAUS (PSAD(TAUS)), and PSA transition zone densities (PSATzD) were compared using receiver operating characteristic (ROC) analysis. RESULTS: Prostate cancer was diagnosed in 58 (24.4%) of the 238 men who underwent prostate biopsies. Of the areas under ROC curves (AUC) of studied parameters, PSATzD (AUC 0.751) was the best and signi fi cantly superior to PSAD(TAUS) (AUC 0.664, P = 0.007). However, PSAD(TAUS) exceeded PSA (AUC 0.559, P = 0.004) and showed potential capability of a one-fourth reduction in unnecessary biopsies without spoiling sensitivity (90%). Cancer detection rate was only 4.2% in the 48 patients whose prostate volume in TAUS was > 50 mL and PSAD(TAUS) was < 0.075. CONCLUSIONS: Since PSAD(TRUS) and PSATzD were signi fi cantly superior to PSAD(TAUS), TRUS is feasible as the standard fashion to determine prostate volume in the diagnosis of prostate cancers. However, TAUS is also worthwhile as it can improve the prostate cancer detection using sole PSA, and primary use of TAUS has the potential to reduce the substantial number of unnecessary biopsy safely.  相似文献   
42.
BACKGROUND: We retrospectively evaluated the erectile function after nerve-sparing radical retropubic prostatectomy (RRP) and the efficacy of sildenafil for erectile dysfunction (ED) following RRP according to the preoperative erectile function. METHODS: We evaluated 48 Japanese patients who underwent nerve-sparing RRP at the Sapporo Medical University School of Medicine, Sapporo, Japan, between January 1996 and December 2001. Erectile function following nerve-sparing RRP was assessed by a simple mailed questionnaire that was constructed for the study. RESULTS: Of the 48 patients, 36 had normal erectile function preoperatively, but for 12, function was not sufficient to penetrate. The overall estimated recovery rates of any degree of erection were 50.6% at 36 months and 94.3% at 60 months. However, that of erection sufficient to penetrate was only 17.7% at 36 months and was only seen in bilateral nerve-sparing patients. Sildenafil was effective in 9 of 13 ED patients (69.2%) in both nerve-sparing groups. When patients were divided according to preoperative erectile function, no difference was found in the efficacy rate between patients with normal function and those with ED. CONCLUSIONS: Even bilateral nerve-sparing RRP can not always guarantee a sufficient erection. However, sildenafil is effective for ED following nerve-sparing RRP regardless of the nerve-sparing procedure or preoperative erectile function. Thus, preoperative function alone, although depending on its severity, may not necessarily be a reason for exclusion from receiving nerve-sparing RRP if patients want to have the operation.  相似文献   
43.
44.
The absorption, especially the stability and transportability, of the cyclic peptide cyclic glycylphenylalanine (cyclo(Gly-Phe)) and the linear peptides glycylphenylalanine, glycyl-d -phenylalanine and phenylalanylglycine have been studied in rat small intestine. Linear peptides were degraded on the mucosal side and only glycyl-d -phenylalanine appeared on the serosal side. However, cyclo(Gly-Phe) was stable on the mucosal side and appeared on the serosal side. Furthermore, the absorption clearance of cyclo(Gly-Phe) was higher than that of glycyl-d -phenylalanine. In the presence of the peptidase inhibitor bestatin, the degradation of linear peptides was reduced and linear peptides appeared on the serosal side, but only phenylalanylglycine, which is transported by the oligopeptide transporter, was absorbed faster than cyclo(Gly-Phe). The absorption clearance of cyclo(Gly-Phe) was reduced as its concentration was increased from 125 μm to 500 μm . Furthermore, the absorption clearance of cyclo(Gly-Phe) at 125 μm was reduced at 4°C or in the presence of glycylsarcosine and cephalexin, which are transported by the oligopeptide transporter. These results indicated that cyclo(Gly-Phe) was stable enough to be absorbed and was transported in part by the oligopeptide transporter rather than completely by passive diffusion.  相似文献   
45.
A case of mosaic 9p tetrasomy (46,XX/47,XX, + dic[9] [q21]) is reported. Clinical manifestations of the patient were generalized hypotonia, severe mental retardation and characteristic dysmorphic features of 9p tetrasomy. A brief review of the literature is also included.  相似文献   
46.
Abstract The prognosis of 174 patients with cirrhosis during the 1980s (1981–89) was analysed. The estimated survival rates were 87.3% in 3 years and 68.5% in 5 years. During the follow-up period, 58 patients died: 20 of hepatocellular carcinoma (37.7%); 11 of hepatic failure (20.8%); eight of gastrointestinal bleeding (15.1%); and 14 of other causes (26.4%). Multivariate analysis revealed that serum albumin, indocyanine green retention rate at 15 min and white blood cell count were significantly associated with prognosis. The results were also compared to our previous study covering the 1970s (1971–80). The estimated survival rate was significantly improved compared to that during the 1970s (54.3% in 5 years, P < 0.001). In the 1980s, hepatic failure mortality significantly decreased ( P < 0.01), and non-liver-related mortality significantly increased ( P < 0.05). In summary, the prognosis of cirrhosis has improved in recent years, and changes of death cause and prognostic factors were observed. It was concluded that to evaluate the severity and prognosis of cirrhosis, new indices and appropriate classification were necessary.  相似文献   
47.
Sympathetic stimulation is well known to contribute to the genesis of QTU prolongation and ventricular lachyarrhythmias in patients with congenital long QT syndrome. In this study, we performed exercise treadmill testing, isoproterenol infusion (1–2 μg/min), and right atrial pacing (cycle length 500 msec) in 11 patients with congenital long QT (LQT) syndrome (LQT group) and in 12 age- and sex-matched controls (control group). The responses of the corrected QT (QTc; Bazett's method) interval and the TU wave complex tvere evaluated. The QTc interval was prolonged from 482 ± 63 msec1/2 to 548 ± 28 msec1/2 by exercise in the LQT group (n = 11; P < 0.005), and this was associated with fusion of the T waves with enlarged U waves, whereas the QTc interval did not increase with exercise in the control group (n = 12; 402 ± 19 msec1/2 vs 409 ± 22 msec1/2). The QTc interval was also prolonged from 466 ± 50 msec1/2 to 556 ± 33 msec1/2 by isoproterenol in the LQT group (n = 7; P < 0.005) in association with morphological changes of the TU wave complex like those seen with exercise, whereas it was only slightly increased from 399 ± 10 msec1/2 to 436 ± 13 msec1/2 by isoproterenol in the control group (n = 77; P < 0.001). However, the QTc interval did not increase with atrial pacing in the LQT group (n = 8; 476 ± 57 msec1/2 vs 486 ± 59 msec1/2), whereas it was slightly increased from 400 ± 21 msec1/2 to 426 ± 18 msec1/2 by atrial paring in (he control group (n = 8; P < 0.005). These results suggest that sympathetic stimulation plays an important role in the QTU prolongation and marked TU wave complex abnormalities in patients with congenital long QT syndrome.  相似文献   
48.
Diastolic mitral regurgitation has been observed in patients with DDD pacemakers when the atrioventricular (AV) delay was prolonged. However, diastolic mitral regurgitation associated with first-degree AV block has not been fully studied. We examined transmitral blood flow in 24 patients with first-degree AV block and normal cardiac function (ages 35.3 ± 17.4 years), and in nine patients with DDD pacemakers and normal cardiac function (ages 73.1 ± 8.1 years), using pulsed Doppler echocardiography. Diastolic mitral regurgitation was observed in 19 of 24 patients with first-degree AV block. Although PQ interval was shortened from 0.32 ± 0.06 to 0.20 ± 0.05 seconds (P < 0.01) after 1 mg atropine sulfate IV, the interval between P wave (ECG) and the beginning of diastolic mitral regurgitation did not change, while the duration of diastolic mitral regurgitation was shortened from 0.15 ± 0.03 to 0.05 ± 0.03 seconds (P < 0.01). There was a significant correlation between changes in PQ interval and changes in the duration of diastolic mitral regurgifation (r = 0.92, P < 0.001). Although cardiac output (3.9 ± 0.05 L/min) and pulmonary capillary wedge pressure (5.1 ± 1.5 mmHg) were normal in all patients with pacemakers, diastolic mitral regurgitation was observed when the AV delay was prolonged. The critical PQ interval for the appearance of diastolic mitral regurgitation was 0.23 ± 0.01 seconds. In patients with prolonged PQ intervals, delayed ventricular contraction following atrial contraction may be associated with mitral regurgitation in the presence of a reversed AV pressure gradient. The results of this study suggest that diastolic mitral regurgitation occurs not only in patients with DDD pacemakers, but also with AAIR pacemakers when the PQ interval is prolonged. The occurrence of diastolic mitral regurgitation is associated with the pacing mode or the setting of AV delay.  相似文献   
49.
It is well known that some patients with neurally mediated syncope have a feeling of aura before the onset of syncope. A case is reported in which cerebral dysfunction recorded by EEG was present before the onset of a vasovagal reaction. The vasovagal reaction, bradycardia and/or asystole, was preceded by abnormal EEG findings when the patient complained of feeling a headache, photophobia, and nausea. These findings suggest that cerebral hypoperfusion, such as with cerebral vasospasms, before the onset of bradycardia might be involved in the mechanism of neurally mediated syncope in patients with an aura.  相似文献   
50.
The levels of prostaglandin E2 (PGE2), 6-keto-prostaglandin F1α (PGF1α) and thromboxane B2 (TXB2) in endoscopic biopsy specimens from the gastric and duodenal mucosa of healthy volunteers and ulcer patients were measured by radio-immunoassay. The PGE2 and PGF1α levels in the mucosa of the corpus of the stomach were lower and the TXB2 level was higher in 10 patients with gastric ulcer in the corpus than in the 16 healthy subjects. The PGE2 level in the antral mucosa of 14 patients with gastric ulcer in the antrum was lower than in the controls. In 18 patients with duodenal ulcer, PGE2 deficiency was more widespread in the entire gastric and duodenal mucosa while the reduced PGF1α level was limited in the gastric corpus. Lower levels of PGE2 in patients with antral or duodenal ulcer and of PGE2 and PGF1α in patients with corpus ulcer in the anatomical mucosal area including the ulcer site may predispose the mucosa to ulceration.  相似文献   
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