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991.
992.
Antenatal sonographic diagnosis of twin-twin transfusion syndrome (TTTS) is based on findings of a twin oligo-polyhydramnios sequence (TOPS) observed in monochorionic twin fetuses. However, TTTS can develop without a significant characteristic intertwin discordance in the amniotic fluid volumes. We report an uncommon form of TTTS without TOPS showing severe anemia in one twin and polycythemia in the other. Based on sonographic findings, it is considered that the recipient twin became the donor later in gestation, and vice versa. It is concluded therefore that even in the absence of TOPS, the possibility of severe TTTS with a suspected reversal of donor-recipient phenotypes during pregnancy should not be excluded, and serial Doppler studies including the measurement of the middle cerebral artery peak systolic velocity should be routinely performed even in seemingly uncomplicated monochorionic twin fetuses without TOPS.  相似文献   
993.
In view of the fact that in Japan treatment of end-stage renal disease depends disproportionately heavily on hemodialysis and almost negligible on transplants from cadaveric donors (hemodialysis 44.4/100,000; renal transplants 0.31/100,000 per year; cadaveric renal transplants 0.11/100,000 per year (1983 data)), we analysed the cost-effectiveness of hemodialysis and renal transplantation, predicted economic gains under expected changes in variables and described attitudes of the Japanese hampering cadaveric renal transplantation. Adjusted life expectancy of transplant recipients (live and cadaveric combined) under the current technical conditions is longer than that of those on hemodialysis (18.3 vs. 14.7 years) and the cost per year for maintaining the transplant is approximately one third of hemodialysis ($12,000 vs $32,000). If the proportion of cadaveric transplant recipients would increase to the levels of the USA (hemodialysis 30.8/100,000; transplants 2.6/100,000 per year; cadaveric transplants 1.9/100,000 per year (1983 data)) along with improvement in graft survival rate, the life expectancy for transplant recipients in Japan could increase by 2 years, thus reducing the annual cost even further. The current number of patients starting hemodialysis (11,500 cases per year) coupled with their life expectancy predicts the number of patients on hemodialysis to reach equilibrium at around 174,000 in a decade (Japanese population 110 million). Based on current price, their annual cost will be about 5.3 billion dollars. Medical expenditure of this magnitude for such a small fraction of people is expected to become an increasingly strong economic incentive for cadaveric renal transplantation. A review of studies on Japanese attitudes toward cadaveric renal transplantation in both urban and rural areas shows that approximately 60% are in favor of donating their kidney after death, though with the majority of cases the donation is contingent upon agreement of their family. It was suggested that the paucity of cadaveric kidney supply stems mainly from the custom of the Japanese to make decisions by consensus. It was also reported that more than 80% of physicians supported the donation of cadaveric grafts while this rate fell to 40% in case of brain death. As the first heart transplantation was carried out in 1968 under both medically and ethically dubious circumstances, distrust toward the diagnosis of brain death appears to be still quite strong. (Not a single heart transplantation has been attempted in Japan in the past 18 years).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
994.
Information regarding daily intake of sodium (Na) is useful for both normotensive and hypertensive subjects. We measured urinary excretion of sodium (U-Na) and urinary excretion of potassium (U-K) to estimate daily salt intake in a cohort of health screening subjects in Okinawa, Japan. Urine samples were obtained from 2,411 subjects (1,554 men and 857 women) who were examined on a half-day dry-doc at the Okinawa General Health Maintenance Association (OGHMA). Four hundred and one subjects were examined twice, once between September and November in 1997, and once between September and November in 1998. The mean U-Na was 182 mEq/day for men and 176 mEq/day for women. The mean U-K was 54 mEq/day for men and 50 mEq/day for women. U-Na was higher in young men, and U-K was lower in young women. In both men and women, smokers had a significantly lower Na excretion compared to nonsmokers. Subjects treated for hypertension had a significantly lower Na excretion (173 mEq/day) compared to subjects not treated for hypertension (192 mEq/day). Our findings suggest that Na excretion in screened subjects in Okinawa is lower than the national average. Sodium excretion, however, was higher in young men than in elderly subjects, and K excretion was lower in young women than in elderly subjects. Both trends are disadvantageous for controlling hypertension.  相似文献   
995.
We report a clinical study of toxicity and pharmacokinetics of intravenously administered natural interferon-gamma. Twenty three cases with metastatic cancer were given interferon-gamma at doses of 10 X 10(4)-400 X 10(4) IU in single injection. Another twenty three cases were administered at doses of 5 X 10(4)-50 X 10(4) IU/day every day for thirty days. Side effects associated with natural interferon-gamma administration were qualitatively similar to those previously reported for alpha, and beta interferon treatment. After intravenous injection, interferon-gamma was cleared monoexponentially with a short half-life of 120 minutes from the circulation. One case with disseminated thyroid cancer showed minor response.  相似文献   
996.
Effect of human recombinant TNF (rHu-TNF) on tumor blood vessels was investigated in relation to its mode of anti-neoplastic action against Meth A sarcoma in BALB/c mice. The extent of the blood vessel lesion was evaluated by measuring the degrees of blueing and hemorrhage after intravenous injection of Evan's blue. When injected intravenously into mice bearing Meth A cells in the abdominal skin transplanted 8 days previously, rHu-TNF, at doses of 3000 and 10,000 units/mouse produced dose-related lesioning of blood vessels in the sarcoma and the adjacent skin but not in the skin distant from the sarcoma. Similar lesioning of blood vessels in the adjacent skin was seen after intravenous administration of 10,000 units/mouse of rHu-TNF in mice with the sarcoma in which the cells had been selectively killed by intratumoral injection of acetic acid (20%, 0.01 ml). On the other hand, rHu-TNF (10,000 units/mouse, i.v.) produced weak lesioning of blood vessels in the granuloma tissue caused by subcutaneous implantation of felt pellets and in the adjacent skin but not in the operation wound in mice with the sarcoma. These results suggest that rHu-TNF damages newly formed blood vessels, particularly those connected with the sarcoma, without influencing blood vessels in normal skin and healing wounds in mice with Meth A sarcoma.  相似文献   
997.
998.
K Taguchi  Y Suzuki 《Neuropharmacology》1991,30(11):1225-1231
The effects of noxious stimuli and morphine on the serotonergic system in the nucleus raphe magnus were examined by in vivo voltammetry studies, using anesthetized rats. The normal electrochemical signal of 280-300 mV was essentially due to the presence of 5-hydroxyindoles in the nucleus raphe magnus. Heating or pinching produced mean decreases of 21.9 +/- 5.2% and 18.0 +/- 6.1% of control, respectively in the 5-hydroxyindole signal. Non-noxious (brushing or warm water) stimulation did not affect the 5-hydroxyindole signal. A small dose of morphine (0.5 mg/kg, i.p.) enhanced the inhibition of the signal by noxious stimuli but large doses (2.0 or 5.0 mg/kg, i.p.) resulted in lesser reductions of the signal. The value of the 5-hydroxyindole signal was unaffected by morphine alone (0.5, 2.0 and 5.0 mg/kg). Effects of both small- and large-doses of morphine were antagonized by naloxone (1 mg/kg, i.v.). Allopurinol (20 mg/kg, i.p.), a xanthine oxidase inhibitor, decreased the steady signal (40.7 +/- 16.2%). After pretreatment with allopurinol, noxious stimuli-induced decreases, both with and without administration of morphine, were similar to those in nontreated rats. In brief, noxious stimulation was found to decrease 5-hydroxyindole signal in the nucleus raphe magnus; morphine enhanced or attenuated this decrease in the anesthesized rat.  相似文献   
999.
1000.
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