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991.
Continuous hemofiltration/hemodiafiltration in critical care.   总被引:12,自引:0,他引:12  
Continuous hemofiltration and continuous hemodiafiltration (CHF/CHDF) were developed as continuous renal replacement therapy for patients with severe conditons and has come to be widely performed mainly in critical care, taking the place of intermittent hemodialysis. The membrane pore size of a hemofilter used for CHF/CHDF allows passage of substances ranging from 30,000 to 50,000 Da, and the method for solute removal in CHF/CHDF employs the principle of convection, which is advantageous for removing middle- to high-molecular-weight substances. As apheresis therapy to remove pathogenic substances in blood, CHF/CHDF is therefore being investigated for its possible effect on various morbid conditions. It has recently been found that CHF/CHDF removes humoral mediators including cytokines, particularly in severe systemic inflammatory response syndromes such as septic shock and severe acute pancreatitis. CHF/CHDF is thus beginning to be performed for the prevention and treatment of organ dysfunction secondary to septic shock, trauma, or acute pancreatitis. CHF/CHDF is also efficacious as artificial liver support in preventing adverse effects caused by plasma exchange (PE) and for continuous removal of hepatic coma-inducing substances. CHF/CHDF is effective for various morbid conditions not only as renal replacement therapy, but also as apheresis therapy and is expected to be applied more widely in critical care in the future.  相似文献   
992.
993.
The reliability of radiological diagnosis of abnormal pancreatico-choledocho-ductal junction (APCDJ) in comparison with findings of gross dissection of the pancreatic choledocho-ductal junction was studied in 8 patients, based on comparison between radiologic and macroscopic findings of the junction in 99 patients who had received pancreatoduodenectomy. APCDJ, that is the joining of the common bile duct and the pancreatic duct in the pancreatic parenchyma extraduodenally, was identified in 5 patients both radiologically and macroscopically. Macroscopically, the length of their common channel ranged from 20 to 32 mm. with a mean of 29 mm. In the other three patients, APCDJ was misdiagnosed radiologically, for the following reasons. In a patient with pancreatic carcinoma, a rather long common channel, 15 mm in length, while ran in the submucosal layer of the duodenum, was though to be APCDJ on radiologic examinations. In a patient with bile duct carcinoma, an abnormal closing between the common bile duct and the pancreatic duct due to carcinomatous infiltration of the pancreas led to a radiologication misinterpretation for APCDJ. In the last patient, APCDJ was identified only macroscopically, not radiologically, because of a relatively short common channel and the location of common bile duct carcinoma. Thus, APCDJ was clearly identified in patients with a long common channel, whereas it was difficult to identify in patients with a short common channel.  相似文献   
994.
Abstract: The effectiveness of dynamic cardiomyoplasty (DCMP) remains controversial. We hypothesized that effectiveness of DCMP using the latissimus dorsi muscle graft (LDMG) depends on the wrapping method. We analyzed pressure-volume relations (PVR), the left ventricular stroke work (LVSW), and the left ventricular end diastolic volume (LVEDV) changes during nonstimulation and stimulation of the LDMG to evaluate the effect of a new wrapping method of DCMP on the LVSW and the LVEDV changes. The new wrapping technique was evaluated in an acute animal experimental model. In 12 mongrel dogs, we performed continuous measurement of the dimensional and pressure dates of the left ventricle (LV) after the DCMP. The measurement was performed 15 min after wrapping during 5 periods. The duration of one measurement period was 15 s. The animals were divided into 2 groups according to the wrapping method. The heart was wrapped with the LDMG using 2 different methods. For Method 1, Carpentier's method, the heart was wrapped primarily with the distal part of the LDMG, the lateral segment. The vasculoneural pedicle of the latissimus dorsi muscle (LDM) was preserved. For Method 2, the LDM was separated, and the vasculoneural pedicle was cut. The medial sternotomy was performed. The thoracodorsal artery of LDMG was anastomosed to the right internal mammary artery, and the thoracodorsal vein was anastomosed to the right atrial appendage. The heart was wrapped primarily with the proximal part of the “free LDMG,” the transverse segment. Based on the PVR loops, the changes of the LVSW and the LVEDV in both experimental groups were analyzed. The paired t-test was used for statistical analysis. Using Method 1, the LVSW and the LVEDV showed no significant changes during stimulation (stim) of the LDMG, compared with non-stimulation (nonstim) (LVSW: nonstim, 970 ± 168 erg × 103; stim, 1,181 ± 203 erg ± 103; p = 0.126 and LVEDV: nonstim, 36.6 ± 6.7 ml; stim, 37.2 ± 6.8 ml; p = 0.36). Using Method 2, the LVSW was increased, and the LVEDV was decreased during stimulation of the free LDMG, compared with nonstimulation (LVSW: nonstim, 694 ±117 erg ± 103; stim, 846 ± 104 erg ± 103; p < 0.001 and LVEDV: nonstim, 47.7 ± 2.8 ml; stim, 46.8 ± 2.7 ml; p < 0.001). The stimulated free LDMG wrapping of the heart seems to be a more effective wrapping method for DCMP, and it results in an increase of the LVSW and a decrease of the LVEDV, compared with the original Carpentier's rnethod.  相似文献   
995.
Background :
The objectives of this study were to compare the efficacy of 3 modalities (prostate-specific antigen (PSA) assay, digital rectal examination (DRE), and transrectal ultrasonography (TRUS)) in detecting prostate cancer which was pathologically confirmed by TRUS-guided systematic six-sextant biopsy, and to investigate the relationship between the number of positive cores and several clinicopathological parameters.
Methods :
Between 1 992 and 1994, 297 males (155 from a mass screening program and 142 identified as outpatients) with a mean age of 71 years, underwent examinations including PSA determination, DRE, TRUS and systematic six-sextant biopsy, and/or additional directed biopsy.
Results :
Prostate cancer was detected in 93 men. The sensitivity level of the PSA assay was significantly higher (85%) than that of either DRE or TRUS. Patients with an abnormal DRE or TRUS, elevated PSA levels, and those in the T3-T4 category or with moderate to poorly-differentiated adenocarcinomas had more positive biopsy cores (P< 0.05). Also, the relationships of both the number of positive biopsy cores and tumor grade to bone metastasis were significant (P < 0.01). Of 209 hypoechoic areas identified by transrectal ultrasonography, 42% were cancerous, and of 427 isoechoic areas, 1 2% were cancerous. The percentage of positive biopsy cores with hypoechoic areas was 86% in the subjects with a PSA > 10 ng/mL, but low (9%) in subjects with a PSA < 4 ng/mL, and the percentage of negative biopsy cores with a normal TRUS was high (98%) in subjects with a PSA of < 4 ng/mL, but lower (67%) in subjects with a PSA > 10 ng/mL.
Conclusion :
The serum PSA assay was more useful than either DRE or TRUS in detecting prostate cancer. The percentage of bone metastasis increased concomitant with the number of positive biopsy cores, and the positive biopsy rate of hypoechoic areas positively correlated with the PSA level.  相似文献   
996.
The characteristics of serum prostate specific antigen (PSA)in normal Japanese men were studied in 1480 subjects examinedby mass screening (MS) for prostate cancer (Pea) in Gunma Prefecturein 1992. The serum PSA concentration was correlated with patientage. The average serum PSA level increased by 0.04 ng/ml/year.The upper normal limits (95 percentiles)of age specific PSAfor normal men are 1.33 ng/ml for those aged 39–49 years,3.65 ng/ml for those aged 50–59 years, 4.06 ng/ml forthose aged 60–69 years, 5.09 ng/ml for those aged 70–79years and 5.66 ng/ml for those aged 80–89 years. Among227 normal men examined by our MS in 1991 and 1992, the PSAvelocity (PSAV) was calculated to be 0.05 ng/ml/year. Among10 Pea patients with normal PSA levels ( < 6 ng/ml) detectedpreviously by our MS, three had an abnormal PSAV. We demonstratedthe possibility that PSA density could distinguish between Peaand benign prostate hypertrophy. The significance of PSA asa Pea screening modality should be evaluated across multipleage ranges and in combination with previous PSA data and/orprostate volume estimated by sonography.  相似文献   
997.
998.
We reported a case of recurrence of localized thymoma accompanied with hypogammaglobulinemia (Good's syndrome) 20 years after surgery. A 74-year-old man was admitted to this hospital because of mediastinal tumor and chronic pulmonary infection. He had been thymectomised at the age of 55 because of spindle cell thymoma. After that, he had been asymptomatic until January 1997, when he began to have a recurrent productive cough, and low-grade fever. Laboratory findings revealed hypogammaglobulinemia. Percutaneous needle biopsy of the mediastinal tumor revealed spindle cell thymoma. Therefore, hypogammaglobulinemia with thymoma (Good's syndrome) accompanied with a chronic lower respiratory tract infection was diagnosed. Immunologic studies revealed a marked decrease of CD 20 positive cells and decreased lymphocyte activation under the stimuli of phytohemagglutinin and concanavalin A. The thymoma was resected in Dec 1997, but the serum immunoglobulin showed no increase at al.  相似文献   
999.
Abstract: A totally implantable ventricular assist system (VAS), including a drive system and a percutaneous electric energy transmission system, was developed and evaluated in acute animal experiments using adult goats. This newly designed VAS mainly consists of a vibrating tube, coils, magnets, and a jelly-fish valve as the outlet valve. For energy transmission, a new implantable transmitter with a plain weave structure was proposed as a noncon-tacting transform by using the spinal amorphous magnetic fibers. The fluid mechanical and hemodynamic properties and the efficiency of the energy transmission system were evaluated in acute animal experiments using healthy adult goats. This vibrating electromagnetic artificial heart (AH) could generate more than 10 L/min as output volume, with 10 Hz vibration using 20 volts as supplied voltage. The total efficiency of the percutaneous energy transmission system was 76%, and temperature increases were within the acceptable range, suggesting the usefulness of our newly developed implantable VAS.  相似文献   
1000.
The width of low echoic region at the internal ring (WLIR) of an inguinal canal demonstrated by ultrasonography was applied in the preoperative diagnosis of the contralateral side in pediatric patients with inguinal hernia. The ultrasonic diagnosis of 39 pediatric patients with inguinal hernia and 38 children without inguinal hernia under 15 years of age were conducted at Hamamatsu University Hospital from April 1988 to January 1989. The WLIR of children without inguinal hernia were within 6 mm in boys under 15 years of age and within 3 mm in girls under 5 years of age. There were no statistically significant differences between the WLIR of the right side and that of the left side, and the WLIR of the following three age groups also demonstrated no statistical significance: under 1 year of age, 1 to 5 years of age, 5 to 15 years of age. On the other hand, the WLIR of the hernia side of pediatric patients with inguinal hernia were significantly wider than that of the contralateral side in boys and girls under 5 years of age (P<0.01), as well as in boys 5 to 15 years of age (P<0.05). Therefore, we recommend a contralateral exploration for pediatric patients with inguinal hernia when the WLIR is 7 mm or more in boys under 15 years of age and 4 mm or more in girls under 5 years of age.  相似文献   
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