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D Y Lin

Publications and source records attributed to D Y Lin.

At least 91 records · Page 5Linked to original sources
PubMed1994

Role of hepatitis C and delta viruses in the termination of chronic hepatitis B surface antigen carrier state: a multivariate analysis in a longitudinal follow-up study.

Influences of hepatitis delta (HDV) or C virus (HCV) superinfection on the spontaneous clearance of hepatitis B virus (HBV) surface antigen (HBsAg) were investigated in 992 patients. Patients were infected with HBV alone (group 1), HBV and HDV (group 2), HBV and HCV (group 3), or all three viruses (group 4). They were followed for 6.2 +/- 3.7 years. Thirty-six patients (3.6%) had spontaneous serum HBsAg clearance. There was an increasing linear trend in the annual incidence from 0.43% (group 1) to 0.64% (group 2), 2.08% (group 3), and 2.33% (group 4; P < .0001). Relative risk (RR) of group 3 to 1 was 4.8 (P < .001) and of group 4 to 1 was 5.1 (P < .02). RR was significantly higher in group 3 than 2 (P < .02). By Cox multivariate regression analysis, only HCV superinfection and age at entry were significant influencing factors. Moreover, there was a significant interaction between HCV and age. Patients > 35 years old with HCV had a higher HBsAg clearance rate. Results suggest that HCV is the most important hepatotropic virus that enhances HBsAg clearance in chronic hepatitis B.

Adolescent↗
PubMed1994

Regression analysis of multivariate grouped survival data.

Multivariate failure time data arise when each study subject may experience several types of event or when there are clusterings of observational units such that failure times within the same cluster are correlated. The failure times are often subject to interval grouping or have truly discrete measurements. In this paper, the marginal distribution for each discrete failure time variable is formulated by a grouped-data version of the proportional hazards model while the dependence structure is unspecified. Generalized estimating equations in the spirit of Liang and Zeger (1986, Biometrika 73, 13-22) are proposed to estimate the regression parameters and survival probabilities. The resulting estimators are consistent and asymptotically normal. Robust estimators for the limiting covariance matrices are constructed. Simulation studies demonstrate that the asymptotic approximations are adequate for practical use and that ignoring the intracluster dependence in the variance-covariance estimation would lead to invalid statistical inference. A psychological experiment is provided for illustration.

Age Factors↗
PubMed1994

Long term survival of a patient with a regressed giant hepatocellular carcinoma after transcatheter hepatic artery embolization (TAE) complicated with liver abscess.

A 62-year-old male patient with histologically proven hepatocellular carcinoma, received transcatheter hepatic artery embolization (TAE) therapy. Development of right pyothorax and liver abscess at the tumor region occurred 4 months later after TAE. Aeromonas hydrophila was isolated from the liver abscess. After repeated percutaneous drainage, the abscess cavity disappeared and the tumor became undetectable by ultrasonography. Nineteen months after the initial presentation, a second tumor at the dome of the right lobe liver was found. TAE was repeated. Bile stasis with stricture of left intrahepatic ducts were found by Tc-99m HIDA cholangiography and endoscopic retrograde cholangiography. The patient had a normal lifestyle until the third tumor appeared at the right lower liver 18 months after the second TAE. TAE was conducted a third time. A shunting between the hepatic artery and vein developed at the new tumor area 3 months later. The patient is surviving today which is five and a half years after the initial diagnosis. We believe that the liver abscess after TAE contributed to the complete regression of the giant tumor, in addition to the anti-tumor effect of the successful TAE.

Carcinoma, Hepatocellular↗
PubMed1993

Evaluating the role of CD4-lymphocyte counts as surrogate endpoints in human immunodeficiency virus clinical trials.

In human immunodeficiency virus clinical trials, the CD4-lymphocyte count has been regarded as a promising surrogate endpoint for clinical efficacy measures such as time to opportunistic infection and survival time. In the present paper, we test this hypothesis according to a criterion proposed by Prentice. This criterion requires the surrogate variable to capture the entire effect of treatment on the clinical endpoint, and it is satisfied if the hazard rate of the clinical endpoint is not affected by treatment among patients with the same preceding history of the surrogate variable. We analyse data from two completed zidovudine trials using the Cox regression model with the CD4-lymphocyte count as a time-varying covariate. The results indicate that the CD4-lymphocyte count captures part of the relationship between zidovudine and time to a first critical event but does not fulfil the Prentice criterion.

AIDS-Related Complex↗
PubMed1993

Ultrasonographic changes of early liver cirrhosis in chronic hepatitis B: a longitudinal study.

Ultrasonography of prospectively followed chronic hepatitis B patients who developed liver cirrhosis were reevaluated in order to identify the ultrasonographic changes of early cirrhosis. Ultrasonographic features of 29 patients before and after cirrhosis were as follows: portal vein diameter--1.20 cm/1.29 cm (NS); cirrhosis score--5.69/7.52 (p < 0.01); spleen size index--21.99 cm2/25.84 cm2 (NS). The result suggests that ultrasonographic diagnosis of early cirrhosis is not easy on a single occasion; however, the score system method is helpful in longitudinal follow-up chronic hepatitis patients. A careful comparison of hepatic parenchymal and surface changes are mandatory.

Chronic Disease↗
PubMed1993

MULCOX2: a general computer program for the Cox regression analysis of multivariate failure time data.

Multivariate failure time data is commonly encountered in biomedicine, because each study subject may experience multiple events or because there exists clustering of subjects such that failure times within the same cluster are correlated. MULCOX2 implements a general statistical methodology for analyzing such data. This approach formulates the marginal distributions of multivariate failure times by Cox proportional hazards models without specifying the nature of dependence among related failure times. The baseline hazard functions for the marginal models may be identical or different. A variety of statistical inference can be made regarding the effects of (possibly time-dependent) covariates on the failure rates. Although designed primarily for the marginal approach, MULCOX2 is general enough to implement several alternative methods. The program runs on any computer with a FORTRAN compiler. The running time is minimal. Two illustrative examples are provided.

Age Factors↗
PubMed1993

High incidence of hepatitis C virus infection in hemodialysis patients in Taiwan.

A longitudinal follow up of 202 hemodialytic patients were conducted to evaluate the incidence of hepatitis C virus (HCV) infection in this high-risk group. A total of 113 patients were found to be seronegative for anti-HCV at the start of this study period. During the average follow-up period of 39 months, 51 patients developed anti-HCV later (group I), while the remaining 62 patients (group II) were seronegative throughout the study period. The results showed that the incidence of HCV seropositivity is 14.6% per year. Longer periods of hemodialysis and younger age of the patient, but not reuse of dialyzer or sex, were correlated with a higher positive rate of anti-HCV. Clinical hepatitis episodes occurred more frequently in group I (56.9%), while persistently normal alanine aminotransferase (ALT) was observed more often in group II (54.8%). There was no significant changes in hepatitis B surface antigen (HBsAg). A total of 41 patients developed hepatitis among the 59 patients who received transfusions, but there was no significant difference between the two groups. We conclude that HCV infection is the main cause of hepatitis in hemodialysis. The longer the patient underwent hemodialysis, the higher the anti-HCV positive rate became, which did not seem to be related to transfusions. Once infected, there is a low disappearance rate of anti-HCV. The exact route of transmission awaits further investigation.

Adolescent↗
PubMed1993

Measurements of urinary growth hormone in the assessment of its secretory status.

A highly sensitive enzyme immunoassay was used to measure urinary growth hormone (GH) levels in 29 children and 32 adults with different levels of GH secretion. The 24-hour urinary GH excretion of seven children with complete GH deficiency was 1.90 +/- 1.55 ng/g Cr (mean +/- SD), of 10 normal but short children was 19.04 +/- 14.11 ng/g Cr, of 12 children with normal height was 14.57 +/- 5.53 ng/g Cr, of 11 adults of normal height was 4.46 +/- 4.47 ng/g Cr, and of six adults with acromegaly was 366.75 +/- 349.95 ng/g Cr. The nocturnal urinary GH excretion of seven children with complete GH deficiency was 2.27 +/- 1.22 ng/g Cr, of 10 normal but short children was 22.74 +/- 12.76 ng/g Cr, of 12 children of normal height was 22.40 +/- 11.86 ng/g Cr, of 26 adults of normal height was 7.14 +/- 5.86 ng/g Cr and of six adults with acromegaly was 338.70 +/- 309.12 ng/g Cr. There was no overlap in the urinary GH excretion, either 24-hour or nocturnal values, between children with complete GH deficiency and children without GH deficiency, or between adults with acromegaly and normal adults. These data indicate that urinary GH measurements can reflect the endogenous GH secretory status and may be a promising tool for the diagnosis of complete GH deficiency in children and acromegaly in adults.

Adolescent↗
PubMed1993

Liver transplantation for a hepatitis B-related cirrhotic patient.

A patient with chronic end-stage liver cirrhosis resulting from a hepatitis B viral infection had a successful liver transplantation performed on 1 July 1991. Preoperative serology revealed that both HBsAg and HBeAg were positive, and the anti-HBs antibody was negative. Immunoprophylaxis included active immunization, as well as injections of large doses of hepatitis B immunoglobulin (HBIG) given perioperatively to reverse the antigen status. The patient has been anti-HBs antibody positive for more than 10 months since the transplantation. The immunoprophylaxis protocol used has been effective in the prevention of hepatitis B viral reinfection.

Adult↗
PubMed1993

Eosinophilic gastroenteritis: 10 years experience.

Eight patients (five men, three women), mean age 36.9 +/- 13.5 (17-60) yr, were diagnosed to have eosinophilic gastroenteritis. The condition was proved in five patients by biopsies through endoscope, and in three, by operation. All had hypereosinophilia (absolute eosinophil count of 1,337-21,787/cm3). According to Klein classification, two had mucosal disease, three had muscle layer disease, and three, subserosal disease. The most common symptoms were abdominal pain (100%), diarrhea (62.5%), vomiting (62.5%), and nausea (50%). Four patients (50%) had symptoms for more than 1 yr before diagnosis. Barium studies revealed mucosal edema and/or thickening of the small intestinal wall in three cases (including one case with ulceration), partial gastric outlet obstruction in one case, and narrowing of lumen of the terminal ileum in one case. Hypotonic duodenogram revealed double contour in one case. Ultrasound examination revealed thickening of the intestinal wall in two cases; computer tomography revealed thickening of the intestinal wall in one case. All patients were treated with steroid (40 mg/day for initial dose and relapse; 5-10 mg/day for maintenance). The symptoms subsided and the eosinophil counts returned to normal within 2 wk in seven patients and 1 month in one. Of six patients being followed up for 2-10 yr, one had remission, four needed small maintenance dose of steroid, and one suffered from relapse with intestinal perforation.

Adolescent↗
PubMed1992

GOFCOX: a computer program for the goodness-of-fit analysis of the Cox proportional hazards model.

GOFCOX is a user-friendly FORTRAN program for assessing the adequacy of the Cox proportional hazards model. The underlying methodology is based on the comparison of the maximum partial likelihood estimator and a weighted parameter estimator. The latter is the root to an estimation equation that assigns varying weights to the individual contributions to the partial likelihood score function. The weighted and unweighted parameter estimators have the same expectation under the Cox model, but tend to differ when the model is inappropriate. The GOFCOX program computes a rich class of weighted parameter estimators and corresponding goodness-of-fit test statistics. The program runs on both mainframe computers and microcomputers. The running time is minimal even for large data sets. A simple example is provided to illustrate the features of the program.

Computers, Mainframe↗
PubMed1992

The prevalence of hepatitis C virus antibodies in patients treated with continuous ambulatory peritoneal dialysis.

OBJECTIVE: To assess the prevalence of anti-HCV (hepatitis C virus antibodies) in continuous ambulatory peritoneal dialysis (CAPD) patients and staff members. DESIGN: Fifty-nine serum samples were collected and tested by an enzyme immunoassay for anti-HCV. Records and past history of blood transfusion and hemodialysis were reviewed. Results were analyzed using the Fisher's exact test. SETTING: A medical college-operated teaching hospital. PARTICIPANTS: Fifty-two patients and 7 staff members from the Chang Gung Memorial Hospital CAPD unit were studied. RESULTS: Anti-HCV prevalence in patients and staff were 15.4% and 0%. A history of maintenance hemodialysis was associated with a higher prevalence of anti-HCV (33.3% versus 5.9% without hemodialysis, p = 0.015). The prevalence of anti-HCV did not increase with longer CAPD duration. Among those with an episode of hepatitis, higher prevalence of anti-HCV was observed (57.1% versus 8.9% without hepatitis, p = 0.0073). CONCLUSION: HCV is an important agent of hepatitis in CAPD patients. The risk of HCV infection among CAPD staff members is negligible. CAPD offers better control of HCV infection among patients with end-stage renal failure.

Blood Transfusion↗
PubMed1992

Retrograde jejunogastric intussusception caused by a jejunal polyp.

A 70-year-old male presented with epigastric pain, vomiting and upper gastrointestinal bleeding 11 years after a subtotal gastrectomy. Retrograde jejunogastric intussusception was diagnosed by endoscopy and barium meal study and finally confirmed by laparotomy. After reduction of the intussusception, a small polyp was found at 20 cm distal to the anastoma, which served as the leading point of intussusception. The pathophysiology and clinical manifestations of this disease were reviewed.

Aged↗