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D Li

Publications and source records attributed to D Li.

At least 847 records · Page 47Linked to original sources

Retinoma and phthisis bulbi of retinoblastoma. 1. Clinical and genetic analysis.

Retinoma and phthisis bulbi of retinoblastoma are rare entities found in retinoblastoma patients and their relatives. Eleven cases of phthisis bulbi of retinoblastoma and 9 cases of retinoma were identified from 1966 to 1991 in our center. The clinic data show that retinoma and phthisis bulbi are closely related to the retinoblastoma gene. Enucleation should be carried out as soon as possible without hesitation for the phthisis of eyes with retinoblastoma. Genetic counseling and frequent observation should be paid attention to retinoma patients and their offspring. The mechanism of retinoma developed is discussed. We propose that the diversity of second mutation might be the cause of retinoma.

Adult↗

[Effects of aluminum, fluorine and their mixtures on the enzyme activities of jejunal mucus membrane in the perfusion of small intestine of rats in vivo].

Buffer (control), F as NaF (100 mmol/L), Al as AlCl3 (32 and 170 mmol/L) and the two mixtures of Al and F (Al:F = 0.3:0.7 and 0.7:0.3) in Tris-buffered media of pH 7.0 were respectively perfused through the small intestine of rats over a period of 40 min. The jejunum was taken out from each animal immediately. Some of its parts were for HE staining; and the others for enzyme histochemical staining. Fifteen enzymes were observed. The results showed that (1) Fluorine chiefly inhibited the metal-enzymes and metal-activated enzymes; aluminum mainly depressed the activities of enzymes in relation to the cell energy metabolism, such as hydrogenases and oxidase. (2) The decreased activities of enzymes induced by Al or F increased significantly after mixing with each other, indicating that the simultaneous existence of Al and F decreased their ionic concentrations, so that strong antagonistic effects on the inhibition of enzymes were noticed since F or Al inhibited enzyme activities by their ions. (3) A high dose of Al intensively inhibited the enzymes related to the cell energy metabolism, which explained why less quantity of Al was absorbed in animals with high dose of Al than that of low dose Al seen in the absorption experiment. (4) The enzyme activities in the animals given high dose of Al mixed with F apparently were elevated in comparison with that in the animals given a pure high dose of Al which was the result of antagonistic effects of F on the inhibition of enzyme activities by Al, therefore the quantity of the absorbed Al was high.

Aluminum↗

[Color Doppler flow imaging in gallbladder tumors].

Thirty patients (22 male, 8 female, age range 25-83) with gallbladder (GB) masses or thickened GB wall found by real-time sonography were studied by duplex and color doppler ultrasonography. All the patients were confirmed pathologically after surgery. Seven of 8 patients with primary GB malignancy (adenocarcinoma 7, malignant fibrous histiocytoma 1) showed high velocity arterial blood flow signal (VABFS) in the tumor masses. No VABFS was observed in 10 patients (metastatic adenocarcinoma 3, adenoma 5, polyps 2). All the 10 patients with primary GB carcinoma (masses 8, wall thickening 2) showed high VABFS in the GB wall. In contrast, no VABFS was found in the GB wall in 3 patients with metastatic GB carcinoma. In 17 patients with benign GB lesion (adenoma 5, polyps 2, xanthogranuloma 2, chronic cholecystitis 6, subacute cholecystitis 2), only 5 (polyps 1, xanthogranuloma 1, chronic cholecystitis 1, subacute cholecystitis 2) demonstrated low VABFS. High VABFS in the GB masses or GB wall, a significant feature of primary GB carcinoma, is helpful in differentiating primary GB carcinoma from metastatic and benign GB lesion.

Adenocarcinoma↗

[Antiarrhythmic effects of kappa-seleno-carrageenan in experimental animals].

The effect of Kappa-seleno-carrageenan, an organic compound containing selenium, on aconitine, BaCl2 and ouabain-induced arrhythmias were studied. When rats were given ip 9 mg.kg-1.d-1 x 5 d or ig single dose of 35, 70, 140 mg.kg-1, the threshold dose of aconitine was elevated significantly to induce HA. The effect seems to resemble that of ip Na2SeO3 1 mg.kg-1 x d-1 x 5 d. With increasing ig dose, the threshold dose of aconitine was elevated for inducing VE, VT, VF. When ip 9 mg.kg-1 x d-1 x 5 d or ig 70 mg.kg-1 was given, the threshold doses of BaCl2 in inducing VF (in rats) and ouabain in inducing VE (in guinea-pig) were elevated. However, no influence was observed for ip Na2SeO3 1 mg.kg-1 x d-1 x 5 d.

Aconitine↗

Ventricular size, cognitive function and depression in patients with multiple sclerosis.

The purpose of this study was to explore further the hypothesis that changes in cognitive function may occur in the mild stages of multiple sclerosis (MS) by determining whether ventricular enlargement was related to cognitive function. Ten measures of ventricular size were made in a sample of 123 MS patients with mild disability and 60 well-matched healthy controls. In addition, sixteen tests of cognitive function and the Beck Depression Inventory were administered. For the MS group, there were significant correlations between the ventricular measures and cognitive performance but not for the normal controls. Scores on the Beck Depression Inventory were not correlated with either cognitive performance or ventricular enlargement. These findings suggest that for the MS group cognitive impairment was related to the disease process but not to the level of depression.

Adult↗

Nude mouse interim host model for human parathyroid grafts. I. Structure and secretory function.

Human parathyroid (PTG) tissues from cadaver (C-PTG), fetus (F-PTG) and PTG adenoma (A-PTG) were transplanted into the kidney subcapsule of Balb/C nude mice as interim host. The structure and secretory function of the tissues were checked 30, 60, 90, 120, and 150 days after operation. The results showed that PTG tissues from all three donors could retain their structure and secretory function for more than 100 days in the nude mice. The growth and function of PTG tissues from the three donors in nude mice were compared.

Adenoma↗

Nude mouse interim host model for human parathyroid grafts. II. Alteration of MHC antigens in human PTG grafts in the nude mouse.

Human parathyroid (PTG) tissues from cadaver (C-PTG), 5-month fetus (F-PTG) and PTG adenoma (A-PTG) were transplanted into the kidney subcapsular areas of Balb/C nude mice as interim host. Dynamic changes in the amount of tissue major histocompatibility complex (MHC) antigen present within the transplantation period were observed. The results showed that during 100 days of interim hosting, no obvious changes in the expression of tissue MHC class I antigens were seen, but the expression of tissue MHC class II antigens was significantly reduced. The changes of MHC antigens in different donor human PTG tissues were compared.

Adenoma↗

[Aluminum and fluorine in blood and bone of rats fed on diet mixed with various contents of aluminum, fluoride or their mixture].

Wistar rats were divided into 8 groups:control, 300 ppm F, 130 ppm F, 300 ppm Al, 1200 ppm Al, 130 ppm Al + 130 ppm F. 300 ppm Al + 300 ppm F and 1200 ppm Al + 300 ppm F. The chemicals were mixed into the standard diet. The animals were fed on the diets for 12 weeks. Contents of F, Al, Ca and P in the blood (or serum) and humerus were determined at the end of 12 weeks. The results showed that the level of F in the blood and bone in the unadulterated F group was increased, especially F in the bone reached a level more than 10 times that of the control. In the 3 mixture groups, blood F and bone F were lowered, while blood F was restored to normal level, but bone F was not nevertheless, the results showed that Al was in antagonism to the absorption of F. In the unadulterated Al groups, blood and bone Al did not parallel with the amount of Al administered. The level of Al in the median Al group was higher than that of the high Al group. Taking the level of blood and bone Al as a measure, when different doses of Al were administered with F, in the low and median dosage of Al, F was in antagonism to Al absorption, but in case of high dosage of Al, F was in potentiation to Al absorption. In all the experimental groups serum P was elevated, but serum Ca was not disturbed. Bone Ca and P were decreased only in the 3 groups with unadulterated F as well as unadulterated and adulterated high dosage of Al. Mechanism of the nonlinearity of Al absorption vs Al dosage, as well as the dual effect of F on the absorption of Al was proposed.

Aluminum↗

Serum concentration fluctuation and bioavailability comparison between indomethacin sustained-release and conventional capsules during steady state.

The comparison between indomethacin conventional capsule (CC) po 25 mg q 8 h or 25 mg tid and indomethacin sustained-release capsule (SRC) po 25 mg bid in human by crossover design showed that both maximal serum concentration (Cmax) and fluctuation index (FI%) of SRC were significantly lower than those of CC during steady state (P < 0.01). No practical differences were observed between the 2 preparations in the trough serum concentration (Cmin) and area under serum concentration-time profiles (AUC0-tau) (P > 0.05). The time period reaching maximal serum concentration (Tmax) of SRC was much more delayed than that of CC (P < 0.01). It suggested that SRC possesses a better controlled release property and could avoid a higher serum peak concentration of CC.

Adult↗

Copper metabolism in new mutant Long-Evans cinnamon (LEC) rats causing hereditary hepatitis: gastrointestinal absorption and distribution of radioisotopic copper (64Cu).

Long-Evans cinnamon (LEC) rats 60 days old showed a concentration of 127.7 +/- 10.9 micrograms/g of Cu in the liver, compared to 1.6 +/- 0.1 micrograms/g in Fischer rats 60 days old. At 2 hr after an oral injection of 64Cu, total retention of 64Cu in the whole blood, liver and kidneys was 16.8 +/- 3.4% of the dose in LEC rats, compared to 13.1 +/- 1.3% in Fischer rats. The recovery rates of retained-64Cu in the livers in LEC and Fischer rats were 82% and 59%, respectively. More than 90% and about 60% of hepatic 64Cu existed in the cytosol fraction in LEC and Fischer rats, respectively. Furthermore, more than 90% of the cytosolic 64Cu was found as MT in LEC rats. In Fischer rats, this proportion was about 60%. In the duodenum mucosal cytosol fraction from LEC rats, about 50% of 64Cu was bound to metallothionein (MT) protein. In Fischer rats, this proportion was less than 20%. When a 64Cu compound was intraperitoneally injected, 70% and only 15% were recovered in the liver 20 hr after the injection in LEC and Fischer rats, respectively. Furthermore, LEC rats showed very low 64Cu activity in the serum, and their duodenal activities were slightly low compared to Fischer rats. These results suggest that the gross accumulation of hepatic Cu is mainly due to deficient excretion of Cu from the liver.

Animals↗

Lumbar subarachnoid catheterization in rats.

An animal model was developed for the study of subarachnoid (spinal) anesthesia and analgesia under unanesthetized, unsedated and unrestrained conditions. Sprague-Dawley rats were anesthetized with intraperitoneal ketamine (75-100 mg.kg-1). A PE10 catheter was inserted under direct vision into the lumbar subarachnoid space, through partial laminectomy of L1 or L2 with or without removal of adjacent intervertebral ligament. One week after surgery, correct position of the catheter was verified by subarachnoid injection of 0.03-0.05 ml of 1.5% lidocaine, which produced temporary hind limb paralysis in all but one animal in 28 consecutive operations. There was neither mortality nor major complication, intraoperatively or postoperatively. Only 2 animals developed minor subcutaneous would infections which responded to incision, drainage and debridement.

Animals↗

Specific reduction of I-compound levels in DNA from spontaneous hepatomas of 22-24 month old male C3H mice.

As previously shown by 32P-postlabeling, I-compound levels are reduced in target tissue DNA of animals exposed to one of several non-genotoxic hepatocarcinogens, e.g. 2,3,7,8-tetrachlorodibenzo-p-dioxin, carbon tetrachloride, peroxisome proliferators and choline-devoid diet. I-compound levels are further reduced, sometimes to undetectable levels, in chemically induced, transplantable rat (Morris) hepatomas and hepatocellular carcinomas induced by peroxisome proliferators or choline-devoid diet. The current study investigated I-compounds in spontaneous hepatic adenomas of genetically susceptible male C3H mice. DNA samples from individual tumors, background livers (non-tumor bearing lobe from tumor bearing mouse) and non-tumor bearing normal livers taken from 22-24 month old animals were analyzed by 32P-postlabeling. I-compound profiles were qualitatively comparable among the three types of tissues. However, levels of most I-compounds were 2.6-5.0 times lower in tumors than in background liver and non-tumor bearing normal liver. There were virtually no differences between background liver and normal liver. Taken together with the previously reported I-compound deficiency in carcinogen-induced hepatomas, the present observations on genetically initiated neoplasms suggest that this phenomenon may play a role in hepatocarcinogenesis and maintenance of neoplasia.

Aging↗