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951.
Doppler velocimetry of the umbilical and intraplacental fetal arteries was studied by color flow mapping in 39 normal pregnancies. The systolic-diastolic ratio (S/D) and pulsatility index of the intraplacental fetal artery downstream to the umbilical artery decreased significantly with advancing gestational age, and its S/Ds were persistently lower than those of the umbilical artery. The difference in the S/D between the umbilical artery and its intraplacental downstream branches decreased with advancing gestational age and approached zero as the pregnancy progressed to term. We conclude that intraplacental fetal arteries, possibly fetal arteries in main stem villi, can be imaged by color flow mapping and that there is a significant "resistance gradient" between the intraplacental fetal artery and the umbilical artery. Intraplacental fetal artery velocimetry using color flow mapping may give further insights into the umbilical-placental circulation. 相似文献
952.
Artificial liver 总被引:7,自引:0,他引:7
Without transplantation, approximately 90% of patients with fulminant hepatic failure die. If patients receive a liver transplant, there is often a lag between the need for and the availability of a donor liver. Therefore, there is a definite need for a liver support system to support the patient's own liver function in fulminant hepatic failure and while awaiting transplantation. We have developed an artificial liver system that not only eliminates lipophilic toxins such as phenols, fatty acids, and mercaptans, but also hydrophilic ones such as ammonia. This artificial liver system consists of a monitor, an extracorporeal blood circuit that uses a hydrophilic polysulfone high-flux dialyzer to remove water-soluble metabolites, and a novel hydrophilic liquid membrane filter to remove lipophilic toxins. In more than 100 in vitro experiments using porcine (5 I) blood, the system was evaluated for its ability to remove toxins that are normally increased in hepatic failure. We found that phenol, cresol, and short- and medium-chain fatty acids can be almost completely eliminated from the blood within 5 h. In animal experiments using pigs, we also found no significant changes of blood gases, liver parameters, electrolytes, and blood cell counts. 相似文献
953.
954.
J Randzio H Kniha M E Gold T T Chang L D Su H H Park J S Cho K Booth D W Furnas 《Annals of plastic surgery》1991,26(2):140-148
Forty-one hemimandible allografts were transplanted in young rabbits immunosuppressed with cyclosporine. The majority of the grafts demonstrated normal wound healing, and growth of hair, bone, and teeth. The mandibular body and the premolars showed significant growth in length. The allografted mandibles functioned sufficiently that the rabbits took oral nourishment soon after surgery. Long-term survival was limited by a toxic "wasting syndrome" specific for rabbits under treatment with cyclosporine. 相似文献
955.
Frydenberg HB 《Obesity surgery》1991,1(3):315-317
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess
vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper
examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting
suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification
are presented. 相似文献
956.
Lai ST Cheng KK Yu TJ Kuo SM Weng Z Chang Y Lee PS Cheng PC 《Journal of clinical laser medicine & surgery》1991,9(6):485-491
From March to July 1989, nine patients at risk for peripheral artery disease underwent intraoperative Nd:YAG laser angioplasty using angioscopy at the Veterans General Hospital (Taipei, Taiwan, Republic of China). Following the laser angioplasty, balloon dilatation was performed in all cases. Eight men and one woman at an average age of 68 were included in the study (range: 58 to 78 years old). Ischemic symptoms included five patients with disabling claudication, four with pain at rest and one with gangrene on the toes. Eight of the nine patients had complete occlusions ranging from 2 to 19 cm in length. Two patients had high degree multiple segmental stenosis of the superficial femoral artery from 1 to 2 cm in length. Initial clinical success (indicated by relief of symptoms and increase in Doppler ankle pressure and index) and improvement in the angiographic luminal diameter was noted in 9 of 10 occluded vessels (90%) that underwent Nd:YAG laser treatment which was delivered at 10 to 12 watts through laser probes. Prelaser intraluminal diameter increased from 0.05 +/- 0.07 to 0.53 +/- 0.07 mm, Doppler ankle pressure index rose from 0.51 +/- 0.12 to 0.81 +/- 0.12, Doppler ankle pressure increased from 62.44 +/- 16.10 to 104 +/- 21.21 mmHg and the amplitude of pulse volume recorder at ankle level rose from 5.77 +/- 2.80 to 12.11 +/- 2.77 mm as compared with prelaser therapy (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
957.
Summary This study was designed to compare the degree of reactive astrogliosis occurring around a puncture wound in the brain of normal rats and at different intervals after a similar puncture wound in rats with a portocaval anastomosis. The gliosis was evaluated by the number of astrocytes, the thickness of their processes and the intensity of the glial fibrillary acidic protein immunoreactivity. After the puncture wound in the brain of rats with a portocaval anastomosis, the gliosis varied at different intervals being: (1) decreased at 10 days, (2) markedly increased at 5 weeks and (3) significantly decreased at 8, 12, and 16 weeks. These findings suggest that 5 weeks after portocaval anastomosis, an active proliferation of the metabolically altered astrocytes occurs with heightened synthesis of glial fibrillary acidic protein in the period of adaptive compensation, the so-called compensatory rebound. At 8 weeks or more after portocaval anastomosis, these altered astrocytes were considered to be in the phase of decompensation and incapable of maintaining the reactive response which occurred in normal rats. The compensatory rebound and decompensatory decline illustrate the dynamic plasticity of the reactive astrogliosis.Supported by grant from the National Foundation of Natural Sciences No. 386-0956. This paper was read at the XIth International Congress of Neuropathology, September 7, 1990 in Kyoto, Japan 相似文献
958.
Inhibition of metabolic cooperation in Chinese hamster V79 cells in culture by various polybrominated biphenyl (PBB) congeners 总被引:2,自引:0,他引:2
Using an in vitro assay system to measure a form of cell-cellcommunication in Chinese hamster V79 cells, several purifiedpolybrominated biphenyl (PBB) congeners were analyzed for theirability to affect colony-forming ability and "metabolic cooperation"in these cells. Results clearly demonstrate the assay's abilityto distinguish differences in the cytotoxic and metabolic cooperation-inhibitingproperties of these congeners related to their structure. Itappears that if a carbon ortho to the bridge carbon of eachphenyl ring is brominated, the molecule has the property bywhich metabolic cooperation is inhibited. The results suggestthat several PBB congeners share at least one property associatedwith several known tumor promoters, such as the phorbol esters.Although we have not ruled out that the mixture of PBB congenersmight contain initiators or that various PBB metabolites wouldbe mutagen/initiators, based on these and other results, itwas concluded that the reported carcinogenic potential of PBBseems to be mediated by its action as a tumor promoter, ratherthan as a complete carcinogen or an initiator. 相似文献
959.
We studied the effect of the opiate antagonist naloxone on the human gastric acid secretory response to three secretory stimulants: sham feeding, pentagastrin, and histamine. Intravenous naloxone (40 g/kg/hr) significantly inhibited the acid secretory response to sham feeding without affecting the serum gastrin response to sham feeding. Naloxone also significantly reduced pentagastrin- and histamine-stimulated acid secretion. These studies indicate that naloxone reduces acid secretion in response to all stimulants of acid secretion yet tested in humans.This study was supported by grants AM-16816 and AM-17328, from the National Institute of Arthritis, Metabolism and Digestive Diseases.Presented in part at the Plenary Session of the American Gastroenterological Association, Salt Lake City, Utah, May 19, 1980. 相似文献
960.
A four-drug combination of intermittent high-dose cyclophosphamide with 5-fluorouracil, hexamethylmelamine, and prednisone was given to 19 patients with advanced breast cancer. Objective response was documented in 7 of 18 evaluable patients. The median duration of response was 99 days. Response was observed in 6/7 patients without visceral disease and 1/11 patients with visceral disease. Toxicity was acceptable and no life-threatening toxicity was observed. Three patients have received the four-drug combination for more than 1 year without serious side effects. This regimen may serve as an alternative treatment for patients without visceral metastasis who have failed to respond to other combination chemotherapy regimens. 相似文献