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排序方式: 共有104条查询结果,搜索用时 31 毫秒
1.
Background and Aim: This study investigated the clinical features of hepatocellular carcinoma in patients with sustained virological response to interferon for hepatitis C viral (HCV) infection. Methods: A total of 7715 patients with HCV infection were treated with interferon and followed up for more than 1 year after withdrawal of interferon in 64 Japanese hospitals and clinics between July 1988 and August 2001. Sustained virological response was obtained in 2515 (32.6%) patients. Of these 2515 patients, clinical data were collected for 38 patients in whom hepatocellular carcinoma developed. Sustained virological response was defined as HCV RNA negativity more than 6 months after the termination of interferon. Results: All patients were HCV RNA negative at the time of diagnosis of hepatocellular carcinoma. The median period until the detection of hepatocellular carcinoma was 4.7 years (range 1.4–9.0 years). There were significant improvements in hepatic function including serum albumin, aspartate aminotransferase, alanine aminotransferase, indocyanine green test, platelet count and histological activity grade in comparison with those before interferon therapy and at the onset of hepatocellular carcinoma. The maximum tumor size in patients without medical follow‐up for 1 year or more (median: 60 mm) was significantly larger than in patients who were periodically followed up for 6 months or less (median: 25 mm) (P = 0.002). Conclusions: The present findings emphasize the importance of regular medical follow up of patients with HCV infection, as even patients showing a sustained virological response to interferon and in whom hepatic function has improved have the potential to develop hepatocellular carcinoma.  相似文献   
2.
We demonstrate here that aniracetam has the ability to block the formation of cytotoxic hydroxyl radicals (· OH) during ischaemia-reperfusion of mouse brain. The fact that brain ischaemia for 40 min followed by reperfusion increased ·OH was evidenced by detection of a peaked increase at 20 min after an ischaemic insult in the formation of 2,3-dihydroxy-benzoate (DHBA) from salicylate in cerebroventricular perfusate, a means of monitoring ·OH formation. A clearcut increase in dopamine was also observed during and after brain ischaemia. The ischaemia-reperfusion mice given aniracetam at an intraperitoneal dose of 30 or 100 mg kg?1 showed a smaller increase in the formation of DHBA than those given the vehicle only. Aniracetam at 100 mg kg?1 significantly suppressed the formation of DHBA by approximately 80%, becoming evident at 20 min after reperfusion and thereafter. Protection against death in mice insulted with a 40-min brain ischaemia (3/13 vs 13/25) was observed following 100 mg kg?1 aniracetam. The increase in the dopamine levels was substantially reduced following aniracetam treatment and the reduction became significant at 20 min after reperfusion and thereafter in parallel with attenuation by aniracetam of DHBA formation. This finding suggests that the inhibitory activity of aniracetam in attenuating the hydroxyl free-radical formation in ischaemic mice is probably due, at least in part, to its palliative action on the dopaminergic neurons.  相似文献   
3.
We tested the hypothesis that pharmacological reduction of the increase in cardiac output during dynamic exercise with a large muscle mass would influence the cerebral blood velocity/perfusion. We studied the relationship between changes in cerebral blood velocity (transcranial Doppler), rectus femoris blood oxygenation (near-infrared spectroscopy) and systemic blood flow (cardiac output from model flow analysis of the arterial pressure wave) as induced by dynamic exercise of large (cycling) vs. small muscle groups (rhythmic handgrip) before and after cardioselective β1 adrenergic blockade (0.15 mg kg?1 metoprolol i.v.). During rhythmic handgrip, the increments in systemic haemodynamic variables as in middle cerebral artery mean blood velocity were not influenced significantly by metoprolol. In contrast, during cycling (e.g. 113 W), metoprolol reduced the increase in cardiac output (222 ± 13 vs. 260 ± 16%), heart rate (114 ± 3 vs. 135 ± 7 beats min?1) and mean arterial pressure (103 ± 3 vs.112 ± 4 mmHg), and the increase in cerebral artery mean blood velocity also became lower (from 59 ± 3 to 66 ± 3 vs. 60 ± 2 to 72 ± 3 cm s?1; P < 0.05). Likewise, during cycling with metoprolol, oxyhaemoglobin in the rectus femoris muscle became reduced (compared to rest; ?4.8 ± 1.8 vs. 1.2 ± 1.7 μmol L?1, P < 0.05). Neither during rhythmic handgrip nor during cycling was the arterial carbon dioxide tension affected significantly by metoprolol. The results suggest that as for the muscle blood flow, the cerebral circulation is also affected by a reduced cardiac output during exercise with a large muscle mass.  相似文献   
4.
ABSTRACT: Using concanavalin A (Con A) crossed-line affinity immunoelectrophoresis and lentil lectin (LCH) crossed-line affinity immunoelectrophoresis, alpha-fetoprotein (AFP) subfractions were studied in sera including three sera from nude mice heterotran-splanted with human yolk sac tumor of the ovary and three sera from patients with yolk sac tumor, mature solid teratoma, or immature solid teratoma of the ovary. In sera of nude mice bearing yolk sac tumor or from a patient with yolk sac tumor, subfractions from yolk sac and those from fetal liver were identified. Since AFP subfractions from yolk sac and fetal liver can be differentiated according to the carbohydrate moieties, our findings indicate that AFP produced by yolk sac tumor and fetal yolk sac are to some extent differently glycosylated. We also found that AFP in both mature and immature solid teratoma was composed of two subfractions ontogenetically originating from yolk sac or fetal liver. All these findings indicate that more than two different factors are responsible for the AFP synthesis in germ cell tumor of the ovary.  相似文献   
5.
In order to determine the reliability of endoscopic biopsy indiagnosis of early gastric cancer, and to clarify the problemswith biopsies, preoperative endoscopic biopsies from 771 earlygastric cancer cases were reviewed and analyzed clinicopathologicallyin comparison with surgically resected specimens. The 771 cancerswere surgically resected at the National Cancer Center Hospitalduring the period from 1972 to 1982. Definite histological diagnosiswas obtained in 87.4% of the carcinomas at the initial biopsies.Repeated biopsy raised the percentage of correct definite diagnosesto 96.1%. False-negative (including suspicion of cancer) diagnosiswas most frequent in the case of depressed lesions (50 lesions).Half of the false negatives were found to be due to samplingerrors by the endoscopists. The other half of these 50 lesionswere diagnosed as "suspicious of malignancy" because of thehistological difficulty in differentiating early gastric cancerfrom regenerative atypia with intestinal metaplasia, or becausethere was not enough information, or for the other reasons.Most of the 31 false-negative diagnoses at the initial biopsyfrom elevated lesions were reported as adenoma (group III) orsuspicious of carcinoma (group IV), indicating that differentialdiagnosis between well-differentiated adenocarcinoma and adenomais very difficult. The result of the present study suggeststhat repeated biopsy from correct sites and discussion of thelesions between clinicians and pathologists are very important. **Present affiliation: Toranomon Hospital, Toranomon 2-2-2,Minato-ku, Tokyo 105, Japan.  相似文献   
6.
Theophylline metabolism in acute asthma with MxA-indicated viral infection   总被引:2,自引:0,他引:2  
BACKGROUND: Although viral infection might alter theophylline metabolism in acute asthma, there are some difficulties in detecting infection due to various kinds of viruses in a clinical setting. METHODS: To evaluate the usefulness of assessment of MxA protein in acute asthma exacerbated by viral infection, MxA protein expression in lymphocytes was assayed by flow cytometric analysis in whole peripheral blood in 21 children (aged 0-6 years) receiving continuous theophylline infusion for management of asthma attack. Serum theophylline levels were measured at 24 and 72 h after initiating theophylline infusion. RESULTS: At the beginning of theophylline infusion, 11 children had increased expression of MxA protein, indicating viral infected states. After 24 h continuous infusion, there were no differences in theophylline levels between MxA-negative and MxA-positive groups. After 72 h infusion, the mean theophylline level of MxA-positive children was significantly higher than that of MxA-negative children (9.7 +/- 2.2 microg/mL vs 7.3 +/- 1.6 microg/mL). The ratio of theophylline clearance at 72 h to that at 24 h in the MxA-positive group was significantly lower than that of the MxA-negative group (1.1 +/- 0.2 vs 1.4 +/- 0.1). CONCLUSIONS: Viral infection appeared to affect theophylline metabolism. Flow cytometric assay of lymphoid MxA protein expression in whole blood is an easy and useful method of evaluating viral infection in acute asthma exacerbation.  相似文献   
7.
A female infant with 21 trisomy syndrome associated with congenital chylothorax was reported. She was born at a gestational age of 34 weeks by Cesarean section because of fetal hydrothorax and hydrops fetus, confirmed by ultrasonography at 32 weeks. Emergent resuscitation and immediate thoracentesis were performed soon after birth. After beginning breast feeding, the serous pleural fluid became opalescent and a diagnosis of congenital chylothorax was made. Feeding was changed to medium-chain triglyceride (MCT) feeding and the production of pleural effusion disappeared after thoracentesis was performed several times. Accumulating evidence suggested that MCT feeding and intermittent thoracentesis under echo guide were effective. Some reports on patients, including this one, suggest that there may be more patients with 21 trisomy associated with congenital hydrothorax. Therefore, congenital hydrothorax might be listed as a complication of 21 trisomy.  相似文献   
8.
KAWASAKI, T., et al. : Determinant of QT Dispersion in Patients with Hypertrophic Cardiomyopathy. QT dispersion is thought to reflect a regional difference in repolarization process although QT interval is composed of depolarization and repolarization. This study was designed to investigate the effect of depolarization and repolarization on QT dispersion in hypertrophic cardiomyopathy. Standard 12-lead ECG was recorded in 70 hypertrophic cardiomyopathy patients with anteroseptal wall hypertrophy (HC-As), 8 patients with lateral wall hypertrophy (HC-L), 8 patients with diffuse hypertrophy (HC-D), and 46 normal controls. QRS, JTc, maximum and minimum QTc, and QTc dispersion were compared. The maximum QTc was greater in HC-As and HC-L than in the control; the minimum QTc was similar in all 3 groups; consequently, QTc dispersion was greater in HC-As and HC-L. In HC-D, the maximum QTc and the minimum QTc were greater than the control, which produced QTc dispersion similar to that in the control. JTc did not differ among 4 groups. In hypertrophic cardiomyopathy, both QTc and QRS duration were increased in the leads coinciding with the left ventricular portion of localized hypertrophy. We conclude that QTc dispersion depended on the heterogeneity of QRS duration or depolarization rather than repolarization, which in fact may be ascribed to the regionally different hypertrophy of the left ventricle in hypertrophic cardiomyopathy. (PACE 2003; 26[Pt. I]:819–826)  相似文献   
9.
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   
10.
Selective effector mechanisms for the expulsion of intestinal helminths   总被引:10,自引:2,他引:8  
In the middle of the era of molecular biology, much less attention is paid to in vivo phenomena. However, carefully designed experimental systems in vivo still can provide valuable information as to the mechanisms underlying the establishment and maintenance of host-parasite relationships. In this review we describe the advantage of using concurrent infections with appropriately chosen combinations of different genera or different maturation stages of parasites to segregate the cellular responses of the host. By means of simple experimental approaches we have found that mucosal mast cells and goblet cells, both of which have long been considered as non-specific effectors, are in fact highly selective and specific effector cells of the host defence mechanisms capable of acting on the establishment and the expulsion of intestinal helminths.  相似文献   
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