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21.
In patients with an implanted DDD pacemaker (PM), the atrial contribution may be interrupted by too short an atrioventricular (AV) delay, and filling time may be shortened by too long an AV delay. The AV delay at which the end of the A wave on transmitral flow coincides with complete closure of the mitral valve may be optimal. The subjects were 15 patients [70.3+/-12.3 (SD) years old] with an implanted DDD PM. Cardiac output (CO) and pulmonary capillary wedge pressure (PCWP) were measured by Swan-Ganz catheter. Transmitral flow was recorded by pulsed Doppler echocardiography. AV delay was prolonged stepwise by 25 msc. When the AV delay was set at 155+/-26 ms, the end of the A wave coincided with complete closure of the mitral valve. When the AV delay was prolonged 25, 50, 75, and 100 ms from this AV delay, the interval between the end of the A wave and complete closure of mitral the valve was prolonged 16+/-5, 39+/-6, 65+/-4 and 88+/-5 ms, respectively (r = 0.97, P<0.0001) and diastolic mitral regurgitation was observed during this period. Thus, the optimal AV delay may be predicted as follows: the slightly prolonged AV delay minus the interval between the end of the A wave and complete closure of the mitral valve. When the AV delay was set at 215 ms, there was a significant positive correlation between the predicted optimal AV delay (166+/-23 ms) and the optimal AV delay (CO: 161+/-26 msec, r = 0.93, P<0.0001, PCWP: 161+/-28 msec, r = 0.95, P<0.0001). In conclusion, optimal AV delay can be predicted by this simple formula: slightly prolonged AV delay minus the interval between end of A wave and complete closure of mitral valve at the AV delay setting.  相似文献   
22.
Aim: Diabetic patients are at higher risk of failure to recover after acute kidney injury, however, the mechanism and therapeutic strategies remain unclear. Erythropoietin is cytoprotective in a variety of non‐haematopoietic cells. The aim of the present study was to clarify the mechanism of diabetes‐related acceleration of renal damage after ischaemia–reperfusion injury and to examine the therapeutic potential of asialoerythropoietin, a non‐haematopoietic erythropoietin derivative, against ischaemia–reperfusion‐induced acute kidney injury in diabetic mice. Methods: C57BL/6J mice with and without streptozotocin‐induced diabetes were subjected to 30 min unilateral renal ischaemia–reperfusion injury at 1 week after induction of diabetes. They were divided into four group: (i) non‐diabetic plus ischaemia–reperfusion injury; (ii) non‐diabetic plus ischaemia–reperfusion injury plus asialoerythropoietin (3000 IU/kg bodyweight); (iii) diabetic plus ischaemia–reperfusion injury; and (iv) diabetic plus ischemia–reperfusion injury plus asialoerythropoietin. Experiments were conducted at the indicated time periods after ischaemia–reperfusion injury. Results: Ischaemia–reperfusion injury of diabetic kidney resulted in significantly low protein expression levels of bcl‐2, an anti‐apoptotic molecule, and bone morphogenetic protein‐7 (BMP‐7), an anti‐fibrotic and pro‐regenerative factor, compared with non‐diabetic kidneys. Diabetic kidney subsequently showed severe damage including increased tubular cell apoptosis, tubulointerstitial fibrosis and decreased tubular proliferation, compared with non‐diabetic kidney. Treatment with asialoerythropoietin induced bcl‐2 and BMP‐7 expression in diabetic kidney and decreased tubular cell apoptosis, tubulointerstitial fibrosis and accelerated tubular proliferation. Conclusion: Reduced induction bcl‐2 and BMP‐7 may play a role in the acceleration of renal damage after ischaemia–reperfusion injury in diabetic kidney. The renoprotective effects of asialoerythropoietin on acute kidney injury may be mediated through the induction of bcl‐2 and BMP‐7.  相似文献   
23.
The absorption of ursodeoxycholate and its tauro-conjugate by the jejunum and the terminal ileum of rat intestine was compared with that of other unconjugated bile acids and taurocholate. In the ligated jejunum, the efficacy of absorption of unconjugated bile acids was in the following order: ursodeoxycholate = deoxycholate > chenodeoxycholate = cholate > lithocholate. This order cannot be explained by the theory that the passive diffusion of bile acids is faster the less hydroxyl bonds in the molecule. These findings on the unconjugated bile acids in the ligated jejunum were further confirmed by perfusion experiments. In the ligated terminal ileum, ursodeoxycholate, cholate and deoxycholate were absorbed as fast as taurocholate or tauroursodeoxycholate, whereas absorption of chenodeoxycholate was significantly slower. The Na+-dependency of the absorption of ursodeoxycholate and cholate in the terminal ileum was confirmed by perfusion studies. In conclusion, intestinal absorption of ursodeoxycholate was efficient in both the jejunum and ileum and these results may contribute to the high availability of ursodeoxycholate in various hepatobiliary diseases.  相似文献   
24.
PURPOSE: Previous studies have indicated that 6-core transrectal prostate biopsy misses a considerable number of cancers. We performed an extensive biopsy protocol of 12-core sampling using both transperineal and transrectal approaches to determine the impact on the cancer detection rate. MATERIALS AND METHODS: We prospectively evaluated 402 men who underwent 6-core transperineal and 6-core transrectal biopsies simultaneously due to abnormal digital rectal examination (DRE) and/or elevated prostate-specific antigen (PSA) levels of 4.0 ng/mL or greater. Using the transperineal approach we obtained four cores from the bilateral peripheral zone targeting the lateral and parasagittal areas and two cores from the bilateral transition zone. The following transrectal biopsy was performed traditionally. We compared cancer detection rate between the extended 12-core procedure and conventional 6-core transperineal and transrectal groups in terms of total PSA and DRE findings. RESULTS: Using the extensive combined method, prostate cancer was detected in 195 cases (48.5%) and the detection rate significantly increased 7.2% and 8.5% compared to the transperineal and transrectal groups, respectively. According to PSA levels and DRE findings, the cancer detection rate by the combined method was significantly improved in patients with PSA levels of 4-10 ng/mL and negative DRE: 10.3% and 11.6% compared to the transperineal and transrectal groups, respectively. CONCLUSIONS: The extensive 12-core method significantly improved the overall cancer detection rate and was especially efficient for men with PSA levels of 4-10 ng/mL accompanied by a negative DRE finding.  相似文献   
25.
We report a case of alanine aminotransferase (ALT) deficiency in a 68-year-old Japanese female with chronic hepatitis C. The serum was positive for antibody to hepatitis C virus (HCV) and HCV-RNA. Liver biopsy showed histological evidence of chronic active hepatitis. The level of serum aspartate aminotransferase (sAST) was elevated, but sALT was extremely low. The patient was followed up for her serum aminotransferase levels for 1.5 years under the treatment with ursodeoxycholic acid. The low sALT level persisted during all the follow-up period. The ALT activity in liver tissue was also decreased. Based on these findings, ALT deficiency was suspected. sALT activity was also found to be low in her two sons. This latter finding suggests the hereditary character of this abnormality.  相似文献   
26.
Organisms routinely cultured from throat swabs and infectious agents of sepsis and/or meningitis were reviewed. During the last 12 years, Klebsiella pneumoniae and Escherichia coli have been replaced by Staphylococcus aureus and Pseudomonas aeruginosa as the predominant isolates from throat swabs after admission. These change in the etiologic pattern of infectious agents of sepsis and/or meningitis, i.e., K. pneumoniae, E. coli, S. aureus, P. aeruginosa and staphylococcus epidermidis, were in agreement with the organisms isolated from the throat swabs after admission. The S. aureus isolated from throat swabs after admission showed a decrease in the bacterial activity of cloxacillin, cephazolin and cefotaxime since 1978.  相似文献   
27.
The distribution of human herpesvirus 6 (HHV-6) and varicella-zoster virus (VZV) was examined in autopsy samples from a fatal case with both virus infections. A 9-month-old boy developed convulsive seizures followed by macular skin rashes, rapidly progressed to brain death, and died 15 days after the onset, when signs of varicella were noted. An isolation of HHV-6 from blood and evaluation of antibody activities to various viral agents including HHV-6 were performed before his death. Postmortem examinations included: (i) isolation of HHV-6 and VZV from tissues or organs; (ii) detection of both virus antigens in tissues or organs by an indirect immunofluorescent assay using monoclonal antibodies to both viruses; (iii) amplification of both viruses and human herpesvirus 7 DNA sequences by a nested polymerase chain reaction assay; and (iv) endonuclease digestion of amplified products of HHV-6 DNA for differentation of variants A and B. Human herpesvirus 6 DNA was detected in peripheral blood mononuclear cells (PBMC) and plasma obtained at the eruptive stage but present only in PBMC 15 days after, indicating the primary infection with HHV-6, although the virus was not isolated from the same blood sample and a significant rise in the antibody titers to HHV-6 was not observed. Both virus antigens and DNA were detected in various tissues or organs obtained at autopsy, but only VZV was isolated from these samples, suggesting disseminated infection with both viruses in an infant. All the amplified products of HHV-6 DNA were variant B. Among the findings for the distribution of virus antigens, it was noteworthy that HHV-6 antigen was demonstrated in the endothelial cells of small vessels in the frontal lobe of the brain. There was no evidence of HHV-7 infection. These data indicate that the primary HHV-6 infection closely followed by the primary VZV infection had the potential hazard of an unexpected and apparently life-threatening event, in which disseminated infections with both viruses were noted in multiple tissues or organs including the brain.  相似文献   
28.
BACKGROUND: The purpose of the present paper was to detect the clinical factors most predictive of red blood cell (RBC) transfusion in extremely low-birthweight (ELBW) infants in the recombinant human erythropoietin era. METHODS: Between 1995 and 2000, 66 ELBW infants were admitted to a level III neonatal intensive care unit. Fifty-four of 66 infants were eligible for enrollment in the present study. Infants were treated with erythropoietin 200 IU/kg per dose s.c. twice a week with 4-6 mg/kg per day iron supplement. RESULTS: The mean gestational age and birthweight were 26.5 +/- 2.1 weeks and 776 +/- 134 g, respectively. Ten of 54 ELBW infants (18.5%) died during the first 21 days. Eight of 10 dead infants (80.0%) and 27 of 44 surviving infants (61.4%) received one or more RBC transfusions. The overall requirement for RBC transfusions in the surviving infants was 3.0 +/- 3.2 per infant/hospital course (range: 0-9) . There were significant differences in gestational weeks, birthweight, initial hemoglobin value, 5 min Apgar score, phlebotomy loss, phlebotomy loss/birthweight, duration of mechanical ventilation, duration of oxygen supplement, and incidence of both intraventricular hemorrhage and chronic lung disease between the transfused and non-transfused group. The predictive variables, initial hemoglobin level (odds ratio [OR] 2.61; 1 g/dL), birthweight (OR 3.00; 100 g), and gestational week (OR 1.89; 1 week), were found to be most predictive for transfusion on logistic regression analysis. CONCLUSION: ELBW infants are still the population at greatest risk for repeated blood transfusions after introduction of erythropoietin treatment. If labor develops, it is often impossible to extend the pregnancy period, therefore efforts should be made to increase hemoglobin level at birth.  相似文献   
29.

Purpose

Although median raphe cysts of the penis have been widely reported the pathogenesis is obscure. We describe the microstructural detection of 3 cases of median raphe to study the true pathogenesis.

Materials and Methods

Three patients presented to our clinic of plastic surgery complaining of abnormal shape of the penis or mass recurrence. High magnification light microscopy and electron microscopy were performed.

Results

Microstructural study revealed that all 3 cases had similar findings to those of the common urethral mucosa.

Conclusions

Median raphe cysts are derived from the external paraurethral ducts and contain features that to our knowledge have not been previously reported.  相似文献   
30.

Purpose

Approximately 15 to 20% of infertile men have azoospermia. In the Y chromosome a deletion, termed the azoospermic factor, has been found in some cases of idiopathic azoospermia. We investigate the relationship of factors in autosomal chromosomes (HLA class I antigens) to spermatogenesis failure in idiopathic azoospermia.

Materials and Methods

We evaluated 65 infertile Japanese men with idiopathic azoospermia. The frequency of the HLA allele reported in 1,216 healthy Japanese men was used as a control. HLA class I typing was performed by the National Institutes of Health standard serological method or polymerase chain reaction-sequence specific primer analysis. Allele frequencies were calculated. We determined statistical significance in the frequency of each allele in patients and controls using the chi-square test. The relationship of HLA antigens to idiopathic azoospermia was expressed as relative risk.

Results

In Japanese men with idiopathic azoospermia the frequency of HLA-A33, B13 and B44 was significantly increased compared with controls. The relative risk of HLA-B44 was 8.4, an extremely high value compared with that of other diseases and HLA antigens.

Conclusions

We suggest that HLA class I antigens are important genetic markers that represent a risk factor for idiopathic azoospermia.  相似文献   
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