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Biomedical subjects

X Ma

Publications and source records attributed to X Ma.

At least 379 records · Page 21Linked to original sources
PubMed1991

[Effects of stimulating periaqueductal gray on the nociceptive neuron discharges of post-thalamic nucleus evoked by stimulation of splanchnic nerve in cats].

The effects of stimulating periaqueductal gray (PAG) on the nociceptive neuron discharges of pronucleus evoked by stimulating the splanchnic nerve in cats were studied. The two kinds of inhibitory action were observed. One was called early phase or prompt inhibition phase which occurred within 30 ms to 150 ms after stimulation of PAG. The other was called slow-pase or sustained inhibition which occurred from a few minutes to more than ten minutes after the stimulation of PAG. The results showed that PAG played an important role in the analgesia of visceral pain. Both kinds of inhibition may be blocked by naloxone, this suggests that endogenous opiate like substances involved in these inhibitory processes caused by stimulating role in the inhibitory effect of PAG.

Animals↗
PubMed1991

Pylorus and antroseromuscular flap-preserving gastrectomy--a new type of reconstruction after subtotal gastrectomy for treatment of gastroduodenal ulcer: clinical and experimental study.

To avoid motility disturbances after Billroth gastrectomy, the authors designed pylorus and antroseromuscular flap-preserving subtotal gastrectomy (PAFPG). Results showed that gastric motility and emptying time of dogs after PAFPG were close to normal. PAFPG was applied to 125 consecutive patients with gastroduodenal ulcers (gastric ulcer, 15 patients; duodenal ulcer, 94 patients; and combined ulcers, 16 patients) confirmed by barium examination and fibro-gastroendoscopy. All patients recovered smoothly, none of them had postoperative complication. Gastric acid output reduction rates were as follows: basal acid output, 85.05% +/- 8.13%; maximal acid output, 81.76% +/- 10.85%; peak acid output, 81.42% +/- 10.15%. The incidence of postoperative enterogastric reflux (endoscopically) and the concentration of cholic acids in gastric juice were significantly lower in patients after PAFPG than after Billroth I or II gastrectomy. Results suggest that PAFPG reduced gastric acid outputs definitely and overcame adverse motility consequences after Billroth I or II gastrectomy desirably.

Animals↗
PubMed1990

[Effects of sodium molybdate on guinea pig atria contractility].

Sodium molybdate (Mo) 10-1000 mumol/L markedly reduced the contratile force of left atria isolated from guinea pig. Mo 100 mumol/L obviously reduced the heart rates in right atria, markedly prolonged the functional refractory period from 185 +/- 12 to 245 +/- 4 ms and inhibited the resting potentiation. Mo 100 and 300 mumol/L reduced the frequency-dependent positive staircase phenomenon. However, verapamil 25 mumol/L reversed the frequency-dependent positive staircase phenomenon to negative one. The mechanism can be explained by the effect on Ca2+ movement in the heart atrium.

Animals↗
PubMed1990

[Clinical uses of digital subtraction arthrography of the temporomandibular joint].

In the present study, digital subtraction arthrography of TMJ upper cavity was performed in 20 cases with TMJ dysfunction syndrome. It was found that digital subtraction arthrography of TMJ can eliminate various overlapping imaging interference of skull components and has great diagnostic value for TMJ dysfunction syndrome, especially for the diagnosis of small meniscus perforation and the location of meniscus perforation. If this technique can be combined with dynamic observation of TMJ arthrography, the diagnoses for various displacement of meniscus can be made more exactly. However, it is impossible to carry out dynamic observation for TMJ when we use this technique only. This is its disadvantage. Therefore, the best way is to combine arthrographic dynamic observation or arthrographic fluoroscopic observation with digital subtraction arthrography.

Adult↗
PubMed1990

[Effects of concentration and ratio of N, P and K on seedlings of Panax quinquefolium L].

Results of the orthogonal experiment of N, P and K are as follows: (1) The highest growth rate occurs in treatment 4 (N100ppm, P25ppm, K250ppm) and other features are also good. So this treatment can be used in hydroponics of seedling of P. quinquefolium. (2) The influences of N, P and K concentration on the contents of ginsenosides in different parts of seedling are different. The content of ginsenosides in aerial part is 14.72-16.72%, higher than 3.24-4.00% in root.

Ginsenosides↗
PubMed1989

Apolipoprotein A-I and A-II levels in an Australian population.

Values for apolipoproteins A-I and A-II (apo A-I and apo A-II) are reported for 389 women and 390 men in the town of Busselton, Western Australia. Apo A-I levels were found to be relatively constant with age in men but to rise with age in women. Apo A-II levels remained constant with age in men until older age, when they declined, but rose with age in women, showing a fall in the oldest age group. Apo A-I levels were greater in women than in men, but apo A-II levels were lower in younger women than in younger men, and higher in older women than in older men. On stepwise multiple regression analysis, neither apo A-I nor apo A-II levels showed an independent relationship with age in women; the same was true for apo A-I in men. Alcohol consumption was directly associated with apo A-I and A-II levels in both sexes; adiposity was inversely associated with apo A-I levels in both sexes but with apo A-II only in women. Triglyceride levels showed an inverse association with apo A-II in women. Frequency of exercise was independently and directly associated with apo A-I and A-II levels in women only.

Adolescent↗
PubMed1989

Contemporary rural-urban migration of the Chinese population.

The author examines rural-urban migration in China. "The present article provides an estimate of the volume of this population flow since 1949, based on a survey of population flow statistics from 74 cities, and discusses the theories and policies on migration."

Asia↗
PubMed1989

[Effects of zinc sulfate on isolated vascular smooth muscles].

ZnSO4 was found to inhibit the contractions of isolated guinea pig aortic preparations induced by KCl, CaCl2 and noradrenaline (NE). ZnSO4 (0.01-0.1 mmol/L) shifted the dose-response curves for KCl, CaCl2 and NE to the right, and depressed their maximal responses with PD2' values of 3.21, 3.07 and 2.91 respectively. ZnSO4 (0.1 mmol/L) significantly antagonized KCl, CaCl2 and NE-induced contraction responses in isolated dog portal vein preparations. These results suggest that the ZnSO4 induced relaxation of vascular smooth muscle might result from its antagonistic effect on transmembrane Ca2+ channels.

Animals↗
PubMed1988

Study of different phases in growth cycle of human bone marrow cells and their growth speed, using rat-human cell hybridization, premature chromosome condensation, and sister chromatid differentiation techniques.

The cytokinetic activity of bone marrow cells is an indication of hemopoietic status. In the routine examination of bone marrow smears, only M phase can be identified, whereas the different phases of the remainder of the cell cycle are not possible to determine. However, by using premature chromosome condensation and bromodeoxyuridine differential staining techniques, cell stage and cell kinetics can be easily determined. Ninety-eight samples of human bone marrow were collected, cells were hybridized with mitotic M3 cells, and 5016 randomly selected hybrid cells were analyzed for cell stage. Our data demonstrated that 80.37% of the cells were in G1 phase, 12.66% were in S phase, 5.29% were in G2 phase, and 1.68% were in M phase. In specimens that had been cultured for 48 h in the presence of bromodeoxyuridine, 57.46% had completed at least two rounds of DNA replication. In 72-h specimens, 69.27% of the cells had completed at least two S phases. In 96-h specimens, 2S and 2S+ cells occupied 74% of the cell population. The use of cell hybridization techniques, premature chromosome condensation, and bromodeoxyuridine-dependent differential staining revealed the phases of the cell cycle distinctly, as well as the kinetics of cell growth.

Animals↗
PubMed1986

[Carcinoembryonic antigen assay in serum and pleural effusion of pulmonary malignancies and benign lesions].

Levels of carcinoembryonic antigen(CEA)in the serum and pleural effusion in malignancies (65) and benign (25) of lung were determined. There are 20 cases of adenocarcinoma, 16 undifferentiated carcinoma, 7 squamous cell carcinoma, 4 alveolar carcinoma, 12 unclassified carcinoma, 1 polymorphous adenoma, 1 mesothelioma, 1 thymoma, 1 metastatic cancer from kidney and 2 metastatic breast cancer. In the benign lesions, there are 20 tuberculosis, 2 heart failure, 1 pneumonia, 1 empyema and 1 cirrhosis. The mean of the CEA level in the serum of lung cancer group was 12.63 ng/ml as compared with that of the tuberculosis group, 3.01 ng/ml (P less than 0.01). The level of CEA in pleural fluid in the lung cancer group was 57.30 ng/ml as compared with that of tuberculosis group, 5.55 ng/ml (P less than 0.01). The content of CEA in the serum and pleural fluid in lung cancer group was remarkably different (P less than 0.01). CEA level in the serum of adenocarcinoma is the highest (mean 15.51 ng/ml). If we set 5 ng/ml as the margin of normal CEA level in serum, the positive rate for cancer would be 54.2%. It is suggested that the margin of CEA normal value be set at 10 ng/ml for the pleural fluid. Higher readings may imply cancer.

Adenocarcinoma↗