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S Y Lam

Publications and source records attributed to S Y Lam.

35 records · Page 2Linked to original sources
PubMed1994

Evaluation of a histogenetic classification for thymic epithelial tumours.

We reviewed 87 thymic epithelial tumours from Chinese patients and typed them according to the Marino and Müller-Hermelink classification as updated by Kirschner and Müller-Hermelink in 1989. Related categories were grouped for statistical analyses: group 1, medullary thymoma and mixed thymoma; group 2, cortical predominant thymoma; group 3, cortical thymoma and well-differentiated thymic carcinoma; group 4, other thymic carcinomas; and group 5, unclassified. Group 3 tumours were more frequently associated with the myasthenia gravis syndrome compared with group 1 tumours (P = 0.001). They also presented at a more advanced stage. Groups 1 and 2 showed an excellent prognosis (100% survival at 10 years). The 10-year survival for groups 3 and 4 patients was 40% and 30% respectively. Pure medullary thymoma made up a higher proportion of our cases (10.3%) than those of a similar Caucasian study (5.3%). The eight thymic carcinomas (group 4) included two thymic lymphoepitheliomas. We conclude that the histogenetic classification evaluated shows a clear correlation with prognosis and clinical features, even when tested on separate geographic groups, where pathogenetic factors may be different. A common approach to classification of thymic epithelial tumours would greatly facilitate future studies on these possible differences.

Adult↗
PubMed1993

Hepatitis C virus antibody in multiply transfused Chinese with thalassaemia major.

Thirty-four of 99 multiply transfused Chinese (49 females, 50 males) with thalassaemia major were positive for antibody to hepatitis C virus. There was no sex predominance in seropositivity with 18 females and 16 males positive. The mean (+/- SD) age and units of blood transfused were significantly higher in the seropositive patients (167 +/- 48 months, 206 +/- 82 units respectively) than the seronegative patients (113 +/- 56 months, 124 +/- 80 units respectively). The seropositive patients had higher mean (+/- SD) serum alanine aminotransferase, aspartate aminotransferase and ferritin concentrations (91 +/- 82 IU/L, 67 +/- 38 IU/L, 4797 +/- 2522 ng/ml respectively) than the seronegative patients (38 +/- 29 IU/L, 48 +/- 28 IU/L, 3620 +/- 2140 ng/ml respectively). Serum ferritin had an independent and significant effect on serum alanine aminotransferase in addition to that of seropositivity to hepatitis C virus.

Alanine Transaminase↗
PubMed1989

Factors affecting fetal loss in induction of ovulation with gonadotropins: increased abortion rates related to hormonal profiles in conceptual cycles.

Thirty-six first-trimester abortions (9.7%), 16 second-trimester abortions (4.3%), 11 ectopic pregnancies (2.9%), and 10 stillbirths (2.7%) occurred in 373 conceptual cycles after gonadotropin induction of ovulation. Fetal wastage was higher in spontaneous pregnancies that occurred before therapy (54.3%, p less than 0.0001) and lower with subsequent spontaneous pregnancies (10.1%, p less than 0.05). Significant risk factors for overall fetal loss during induced ovulation were a continuous rise of estrogen excretion until ovulation (p less than 0.01) and previous abortion (p less than 0.05). For first-trimester abortion, the risk factor was continuous estrogen rise (p less than 0.01); for second-trimester abortion, the risk factors were a low luteal pregnanediol-to-estrogen excretion ratio (p less than 0.002), increased age at conception (p less than 0.02), and high baseline estrogen excretion (p less than 0.05). Multiple pregnancy was not significant. The continuous rising estrogen pattern may serve as a marker of abnormal oocyte maturation. We propose that future studies on infertility treatment should report on pregnancy outcome.

Abortion, Spontaneous↗
PubMed1988

Treatment-independent pregnancies after cessation of gonadotropin ovulation induction in women with oligomenorrhea and anovulatory menses.

Life-table analysis was performed for the cumulative spontaneous pregnancy rate (CSPR) of 56 patients with oligomenorrhea and anovulatory cycles who had been treated with gonadotropin for ovulation induction between 1963 and 1985. Twenty-seven had at least one spontaneous pregnancy, giving rise to a CSPR of 66.4% (95% confidence limit [CL] 42.4% to 90.4%) at 115 months for the first spontaneous pregnancy, which is significantly lower than the cumulative induced pregnancy rate (CIPR) of 88.6% at 23 months for the first course of gonadotropin therapy (P less than 0.0001). This fertility potential was not affected by the baseline estrogen and follicle-stimulating hormone levels, diagnosis, result of gonadotropin therapy, and age and menstrual pattern during exposure to spontaneous pregnancy by Cox regression analysis. More multiple births occurred in the induced pregnancies than in the spontaneous pregnancies (P = 0.005).

Anovulation↗
PubMed1987

Outcome of patients with one ovary in an in vitro fertilization program.

To determine whether the absence of one ovary would influence adversely the outcome of in vitro fertilization, the results of 60 laparoscopic oocyte retrieval procedures in 34 single-ovary patients were compared with the outcome for all laparoscopic retrieval cycles during the same period (January 1984-August 1986) in patients with tubal infertility and two accessible ovaries (559 cycles in 335 patients). The median age was younger in the one-ovary group (31 vs 32) (P less than 0.05). The group with two accessible ovaries had significantly more follicles aspirated (median, 7 vs 5; P less than 0.001) and more oocytes obtained (median, 5 vs 4; P less than 0.001) per retrieval compared with the single-ovary group. However, the single-ovary group had a higher percentage fertilization (69 vs 62%; P less than 0.05) so that the number of embryos transferred per transfer patient (median, 3 vs 3) and pregnancy rate per cycle (9.7 vs 15.6%) did not differ significantly between groups. We conclude that patients with a single ovary have a compensatory increase in the ability to produce oocytes which may have greater potential for fertilization and subsequent development.

Abortion, Spontaneous↗
PubMed1987

Smoking, passive smoking and histological types in lung cancer in Hong Kong Chinese women.

In a case control study in Hong Kong, 445 cases of Chinese female lung cancer patients all confirmed pathologically were compared with 445 Chinese female healthy neighbourhood controls matched for age. The predominant histological type was adenocarcinoma (47.2%). The relative risk (RR) in ever-smokers was 3.81 (P less than 0.001, 95% CI = 2.86, 5.08). The RRs were statistically significantly raised for all major cell types with significant trends between RR and amount of tobacco smoked daily. Among never smoking women, RR for passive smoking due to a smoking husband was 1.65 (P less than 0.01, 95% CI = 1.16, 2.35) with a significant trend between RR and amount smoked daily by the husband. When broken down by cell types, the numbers were substantial only for adenocarcinoma (RR = 2.12, P less than 0.01, 95% CI = 1.32, 3.39) with a significant trend between RR and amount smoked daily by the husband. The results suggest that passive smoking is a risk factor for lung cancer, particularly adenocarcinoma in Hong Kong Chinese women who never smoked.

Adenocarcinoma↗
PubMed1987

Mild to moderate abnormalities of semen do not affect pregnancy rates during ovulation induction with gonadotrophins.

One or more semen analysis results were available for 195 men whose wives responded to ovulation induction with gonadotrophins performed at The Royal Women's Hospital since 1963. Fifty-three men (27%) has subnormal semen analyses by conventional criteria: sperm concentration less than or equal to 20 X 10(6)/ml, motility less than or equal to 40% or normal morphology less than or equal to 50%. The lifetable pregnancy rates were not significantly different for those with subnormal and normal semen (chi 2 = 0.169), by six cycles 64% (s.e.m. = 7) with subnormal semen had conceived compared with 59% (s.e.m. = 5) with normal semen. It appears that lower limits of semen quality could be relaxed for women needing ovulation induction with gonadotrophins.

Female↗
PubMed1987

Reliability of the wetting value of tears.

The wetting value is the length of a Schirmer strip wetted in millimetres for a 5 min test period plus the length of time in seconds for dry spots to appear and has been suggested as a better prognostic test than its components in isolation (Fanti and Holly, 1980). Parameters of these procedures are examined and important shortcomings in the derivation of wetting value discussed. Reliability figures are presented for the Schirmer, tear break-up and wetting value tests. The norms obtained for the tear break-up test are substantially different from those usually assumed and we recommend that practitioners should therefore rely on their own norms rather than published values.

Contact Lenses↗