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This study was based on 150 in vitro fertilization cycles carried out between June 1991 and July 1992. All the patients had blocked or dysfunctional fallopian tubes as the cause of infertility. Clomiphene citrate, human menopausal gonadotropin and hCG were used for controlled ovarian hyperstimulation. The results showed that an urinary luteinizing hormone (LH) surge (LH40 IU/L) occurred in 41 cycles (27.33%), a high LH level (LH = 40 IU/L) in 16 (10.67%), and normal (LH40 IU/L) LH level in 93 cycles, before hCG injection. The average number of oocytes recovered was not affected by the occurrence of a spontaneous LH surge, but the cleavage rate of the fertilized eggs was significantly lower than that in the cycles without LH surge and the rate of clinical pregnancy was also lower, although of no statistical significance. Our results demonstrated that the LH surge had an adverse effect on the egg quality and therefore would probably reduce the chances of pregnancy success.

Two cases of gamete donation in an IVF program were reported in this paper. In the first case the wife with recurrent abortions was found to have chromosomal abnormality, her karyotype was 45,XX,-14,-14 + rob (14 Q 14 Q). She became pregnant after IVF-ET with donated ova, and was delivered of a normal male baby on June 12, 1992. The baby's karyotype was normal. The blood group of both the husband and wife was O, while that of the baby was B. The baby suffered from icterus neonatorum as a result of ABO incompatibility but recovered quickly after treatment. Further DNA finger print analysis of the husband, wife and baby, combined with the history of egg donation IVF, proved the relationship of the parents with the baby. In the second case the husband's karyotype was 46,XY, t(4; 9) (4Q+; 9Q-). The wife had also history of recurrent abortions. Since 1989, the wife received sperm donation IUI 5 times in another hospital without success. IVF-ET with donated sperms was performed in November 1991 resulting in clinical pregnancy. She was delivered of a pair of twins, one male and one female on July 20, 1992. The possibilities of different types of gamete formation during meiosis in carriers of chromosomal balanced translocation were briefly discussed. Donation of oocytes could be realized only in an IVF program, which is also the only way to propagate for the family. However, IVF with donated sperms is indicated in women with blocked tubes besides the male factor or after repeated failures of other assisted reproductive technologies.

Studies on the isolated rat heart perfusion model have proved that perfusion with high Ca2+ (4.5 mmol/L), high K+ (8.7 mmol/L) or free radical generating system (FRGS) significantly increases myocardial uptake of liposomes. Intravenous injection of liposomes covalently combined with antibody of rat myocardial cells obviously elevates the target action of liposomes to myocardium. Liposome-carried SOD for treatment of rat myocardial ischemia-reperfusion injury is much more effective than simple SOD. The results evidence that the liposome as drug carrier for treatment of ischemic heart diseases shows a broad prospect for its clinical use.

Lower hybrid wave (LHW)-plasma coupling experiments in HT-7 [J. K. Xie and HT-7 Group, Proceedings of the 16th International Conference on Fusion Energy, Montreal, 1996 (IAEA, Trieste, 1997), Vol. 1, p. 685] were carried out by means of puffing gas (CD4 and D2) just around the antenna. Both experiments show that wave-plasma coupling is improved by the gas puffing. The maximum distance between the plasma and the antenna is limited to about 8 cm due to the plasma disruption. The variation in the lined averaged density in the different channels gives a possible evidence of the mechanism of the ionization of neutral gas. The effect of the gas flow rate on the wave-plasma coupling shows that an optimized gas flow rate is necessary for good coupling, being consistent with simulation through Brambilla theory qualitatively. Experiments with puffing D2 show that the improved coupling results from the global density increase and the local gas puffing. Langmuir probe measurements indicate that the gas puffing effect...

Two types of plasminogen activator (PAs) are present in human endometrium, and their contents vary with the different phases of menstrual cycle, i.e. high in the proliferative phase and low in the secretory phase. In the present study by immunohistochemical technique, both uPA and tPA antigens were demonstrated in the stromal and glandular cells of the endometrium. In cell culture, tPA was released only from stromal cells and uPA only from glandular cells as determined by SDS-PAGE followed by fibrin overlay technique, but PA inhibitor type-1 (PAI-1) was secreted by both stromal and glandular cells. Furthermore, secretion of PAs from endometrial cells was enhanced by adding estradiol and markedly inhibited by progesterone in a dose dependent manner, while the PAI reacted just in the opposite way. The effect of the peptide hormones, hCG, GnRH, PRL, as well as cAMP in cell culture on the secretion of PAs and PAI was similar to that of estradiol, while forskolin demonstrated definitely more stimulative effect on tPA than uPA. Taking into account of the finding of the present study, it appears that, under hormonal control, a balance between PAs and PAI in the endometrium exists. The physiological roles of the PAs and PAI in the endometrium were discussed.

A study on the persistence, residues and residue distribution of mancozeb in tomato plant-soil system, as well as effects of cooking on transformation of residual mancozeb were carried out with radiotracer technique. Half-life values for total mancozeb residues on tomato leaves and in soil were observed to be 9.5 and 7.6 days, respectively. The results also suggested that mancozeb residues in soil were readily uptaken by plants and leach to soil layer as deep as 28cm within two weeks, although over 90% of the residues remained in the upper layer (0-6cm) of the soil. Translocation of the residues of mancozeb, especially the water soluble metabolites including ETU, throughout the plants could be one of the factors responsible for the contamination of tomato fruits. Deposit of sprayed mancozeb on the fruit skin was another important factor leading to the contamination of fruits. Fruit skin contained higher levels of residues than the pulp. Washing with water could remove more than 50% of the residues on the skin. It was also found that 20-30% of the residual mancozeb degraded to ETU during cooking process. The tomatoes should be washed to reduce the residues of the fungicide and ETU in food.

Different methods of ovum pick-up were used in an IVF program from January 1, 1988 to January 31, 1989. In the initial stage of the program, laparotomy ovum pick-up with surgical treatment of pelvic diseases resulted in two cases of clinical pregnancy in 1987 with full-term delivery of two healthy babies. Transvaginal ovum pick-up with a needle using an ultrasonic endovaginal transducer was started in late 1987. In 1988-1989 the transvaginal method was employed more frequently than laparotomy, and it has become a routine practice in the IVF program. The ultrasonic endovaginal approach seemed to give a low ovum recovery rate (70.99%), but the fertilization rate was high (85.10%, P less than 0.05), and the rate of embryo transfer was 89.33%. The average number of pre-embryo per transfer was 2.26. These figures were quite similar in the two groups. The ultrasonic transvaginal approach for egg retrieval was noninvasive, easily accepted by patients. We suggest that it can be done repeatedly on one patient to improve the cumulative pregnancy rate. However, the laparotomy for ovum pick-up has shown some special merits and is still indicated in some cases.

Umbilical and uterine artery Doppler studies were carried out in 113 cases of normal pregnancy and in 32 patients with pregnancy induced hypertension (PIH). The results were analyzed by calculating the systolic/diastolic (S/D) ratio. In normal pregnancy the umbilical velocity wave S/D ratio declined from 3.9 to 2.1 from 20th week to term, and the uterine wave S/D ratio remained constant between 1.8 and 1.9. In many cases of severe PIH the umbilical and uterine artery velocity wave S/D ratios were raised, indicating increased resistance to the blood flow. The changes of umbilical waveforms appeared earlier than those of the uterine arterial waveforms.

Methods of ovum pickup in the IVF/ET program in our hospital from January 1st 1988 to January 31st 1989, were reported. In the initial stage of the program in 1987, laparotomy follicle aspiration was used, which resulted in two cases of clinical pregnancy and full term delivery. Ovum pickup using an ultrasonic endovaginal transducer with a needle guide was introduced in the latter part of 1987. In 1988, the transvaginal method was employed more frequently than the laparotomy and has since become the routine in our program. The rate of embryo transfer and the average number of embryos transferred were quite similar in the two groups. Either method was adopted at that time according to the facilities available and the characteristic pathological conditions of our patients, of whom most had previous history of operation resulting in severe pelvic adhesions. The transvaginal ultrasonic needle guided method for egg retrieval is non-invasive, readily accepted by the patients and therefore may be done repeatedly on one patient in order to increase the cumulative pregnancy rate. However, the laparotomy (transabdominal) route for ovum pickup together with other pelvic surgeries is still indicated in some cases. The clinical pregnancy rate per transfer showed no statistical difference between the two groups.

Forty-four infertile women in 44 cycles were stimulated by CC/hMG/hCG (39 cycles) and by CC/hCG (5 cycles) for the purpose of in vitro fertilization (IVF, 37 cases with 35 transfers) and gamete intrafallopian transfer (GIFT, 7 cases). Intraoperative ovum pick-up was performed 32-36 hours after hCG injection. Blood E2 and P levels were determined. Blood E2 was found to be proportional to the number of mature and intermediate oocytes obtained, and correlated with the number of follicles (greater than 10 mm) and the total follicular fluid volume. Altogether 213 follicles aspirated were analyzed. There was a highly significant linear correlation (r = 0.72, P less than 0.01) between the follicular diameter (X cm) on the operation day and the aspirated follicular fluid volume (FFV, Y). The equation of the line was Y = 3.8 X-4.4. The higher concentrations of follicular E2, P, FSH, LH and lower T concentration were crucial to the maturing process of oocytes. It was found that mature oocytes could be retrieved from 26.5% of the small follicles, so it is worthwhile to aspirate the small ones. The fertilization rate was much higher with the mature oocytes than the immature ones. But the morphologically mature oocytes might function differently, i.e. the mature oocytes retrieved from the small follicles or from follicles with unbalanced hormonal microenvironment usually give a low fertilization rate.

Birth limitation and late marriage are two major factors which contribute to the reduction of population growth rate. These two factors should be used as the fundamental method for effectively controlling China's population growth. Facts have proved that birth limitation and late marriage are complimentary to each other and should match each other closely. Since late marriage cannot be delayed indefinitely, the average fertility rate for females under the age of 25 in their first marriage may still reach 5-6 children, provided that birth control measures are not taken. Because of this situation, at the same time that late marriage is encouraged, birth control should also be promoted positively. All married couples should be advised to have only one child. In order to ensure the everlasting practice of these two methods, certain policies concerning family planning and birth control should be formulated according to China's current economic situation. These policies include enforcement of an ideological education and social insurance practice in order to solve the problem of the high population growth rate in the countryside and effectively reach the goal of controlling China's population growth.

Taking the puerarin content---the chief constituent of Pueraria lobata---as the index in the mixed decoction of Pueraria lobata etc, we have adopted the method of orthogon al experiment to explore the best decocting conditions for Pueraria lobata. The results show that a better way to decoct Pueraria lobata is to cut the root into slices of 0.4-0.7 cm, and water 12-15 times the weight of the root and decoct for 30 minutes. It makes no big difference whether the root is soaked or not.

A novel heat recovery ventilator, the membrane-based energy recovery ventilator (MERV) that uses water-permeable hydrophilic membranes to transmit moisture, is developed to save the energy for conditioning ventilation air. The yearly performance of a MERV in Hong Kong is carried out by hour-by-hour calculations. It is disclosed that in hot and humid regions like Hong Kong, about 58% of the energy required for conditioning fresh air could be saved with a MERV annually, which recovers both latent and sensible energy; while only about 10% of the energy could be saved with a traditional sensible only energy recovery ventilator (SERV). Compared to the annual cooling load, the energy saving for fresh air with a MERV Is 12.1%, about 5–6 times higher than that with a traditional SERV.