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Zhang MQ, Walczynski K, Ter Laak AM, Timmerman H. Optically active analogues of ebastine: synthesis and effect of chirality on their antihistaminic and antimuscarinic activity. Chirality 1994; 6:631-41. [PMID: 7857774 DOI: 10.1002/chir.530060806] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A series of optically active analogues of the H1-antihistamine ebastine, with chiral center(s) at the benzhydryl and/or phenylbutyl part of the molecule, have been synthesized. Their in vitro antihistaminic and antimuscarinic activities were investigated, along with a molecular modelling study. It was found that introduction of the benzhydryl chiral center yielded significant stereoselectivity for both antihistaminic and antimuscarinic activities. The steric preferences of the benzhydryl chiral center for antihistaminic and antimuscarinic actions were mirror images of each other. The (-)-isomer of 4-methylebastine (6d) showed more than 10-fold higher in vitro antihistaminic potency than ebastine. Meanwhile the selectivity of 6d for histamine H1-receptors was also increased by more than 20 times in comparison with ebastine. The chirality at the phenylbutyl part of the molecule does not significantly alter the antihistaminic or antimuscarinic activity of the compounds although the (S)-isomers showed slightly but unanimously higher antihistaminic activity than the (R)-isomers. These results have been discussed with existing stereoselectivity data of antihistamines and an asymmetric pharmacophore model for H1-antagonists has been described.
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302
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Zhang MQ, Timmerman H. Terfenadine: a mixture of equipotent antihistamine enantiomers without a clear 'isomeric ballast'. PHARMACY WORLD & SCIENCE : PWS 1993; 15:186-92. [PMID: 8257954 DOI: 10.1007/bf01880624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Terfenadine was the first non-sedating histamine H1 receptor antagonist and one of the most frequently prescribed H1 antihistamines. Terfenadine has one asymmetric centre in the molecule and is currently used as a racemate. Different methods and approaches for obtaining pure enantiomers of terfenadine are summarized and discussed in the present paper. Studies on antihistamine activity of the enantiomers, their side-effects on the central nervous system, calcium channel affinity and metabolism are also reviewed and analysed.
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303
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Zhang MQ, Marr TG. A weight array method for splicing signal analysis. COMPUTER APPLICATIONS IN THE BIOSCIENCES : CABIOS 1993; 9:499-509. [PMID: 8293321 DOI: 10.1093/bioinformatics/9.5.499] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A new method of sequence analysis, using a weight array method (WAM), which generalizes the traditional Staden weight matrix method (WMM), is proposed. With the help of a statistical mechanical model, the discriminant function is identified with the energy function describing macromolecular interactions. The method is applied to the study of 5'-splice signals in Schizosaccharomyces pombe pre-mRNA sequences. The results show that there may exist weak pairwise correlations within the signals and that our method can help to better discriminate these signals. Experiments are proposed to test the predictions of the theory.
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304
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Abstract
BACKGROUND Neuroplastic changes following ileum hypertrophy have been reported in intrinsic enteric neurons. The hypothesis in the present study was that intestinal hypertrophy induces neuronal changes in dorsal root ganglia (DRG). METHODS Under sodium pentobarbital anesthesia, partial obstruction was produced in the rat by tying a plastic ring around the terminal loop of ileum. Fast Blue (FB) (Sigma, St. Louis, MO) was injected into the obstructed ileum wall, and the rat was perfused after 8 days. DRG were immunostained and examined to identify and measure sizes of perikarya containing FB and/or calcitonin gene-related peptide (CGRP) or FB and/or substance P (SP). RESULTS Of the DRG neurons that projected to the ileum in control or obstructed animals, approximately 50% were CGRP-immunoreactive (IR) and 30% were SP-IR (colchicine pretreatment was not used). Neurons that projected to the obstructed ileum were increased in size compared with neurons in nonobstructed controls. Some of these neurons were CGRP-IR or SP-IR; some were large FB-labeled neurons that were not SP-IR or CGRP-IR. CONCLUSIONS The morphology of sensory autonomic neurons in adult animals is influenced by dynamic interactions with the targets they innervate, whether directly or transneuronally.
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305
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Zhang MQ, Marr TG. Genome mapping by nonrandom anchoring: a discrete theoretical analysis. Proc Natl Acad Sci U S A 1993; 90:600-4. [PMID: 8421694 PMCID: PMC45711 DOI: 10.1073/pnas.90.2.600] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
As part of our effort to construct a physical map of the genome of the fission yeast Schizosaccharomyces pombe, we have made theoretical predictions for the progress expected, as measured by the expected length fraction of island coverage and by the expected properties of the anchored islands such as the number and the size of islands. Our experimental strategy is to construct a random clone library and screen the library for clones having unique sequence at both ends. This scheme is essentially the same as the clone-limited double sequence-tagged-site selection scheme which was used in a computer simulation by Palazzolo et al. [Palazzolo, M. J., Sawyer, S. A., Martin, C. H., Smoller, D. A. & Hartl, D. L. (1991) Proc. Natl. Acad. Sci. USA 88, 8034-8038]. Both simulation and ongoing experiments in our laboratory have shown that the nonrandom anchoring method is far superior to random anchoring. In this paper, we propose a theoretical model to explain the simulated data and the experimental data.
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306
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Zhang MQ, Caldirola P, Timmerman H. Calcium antagonism and structure-affinity relationships of terfenadine, a histamine H1 antagonist, and some related compounds. J Pharm Pharmacol 1993; 45:63-6. [PMID: 8094450 DOI: 10.1111/j.2042-7158.1993.tb03681.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Calcium channel affinity of terfenadine and its optical isomers was determined by the displacement of [3H]nitrendipine on rat cerebral cortex membranes. Terfenadine showed a pKd of 6.36 +/- 0.03 whereas its R(+)-isomer (VUF4567) had a pKd value of 6.39 +/- 0.03 and the S(-)-isomer (VUF4568) had a pKd of 6.40 +/- 0.04. The same affinity between the enantiomers suggests that the binding domain on the membrane is not sterically restricted towards the part of the molecule in which the chiral centre is present. The characteristics of terfenadine in regulating [3H]nitrendipine binding were similar to those of some other diphenyl-alkylamine type calcium antagonists. It allosterically altered the binding affinity for nitrendipine and acted at the same site linked to the calcium channel as gallopamil. A structure-affinity relationship among a group of terfenadine analogues is discussed.
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307
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Zhang MQ, ter Laak AM, Timmerman H. Structure-activity relationships within a series of analogues of the histamine H1-antagonist terfenadine. Eur J Med Chem 1993. [DOI: 10.1016/0223-5234(93)90009-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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308
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Zhang MQ. [In vitro measurement of antibacterial activities of topical antibacterial creams]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1992; 30:272-3, 316. [PMID: 1289001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A new method of in vitro measurement of antibacterial activity of different antimicrobial creams is introduced in this paper. The tested cream in known quantity is uniformed suspended in a solid medium, and bacteria of known quantity are inoculated. The result is expressed in MIC. In this observation, four creams were tested against 3 bacteria. It is the authors impression that the new method is better than the traditional disc method, as it reflects better the actual antibacterial activity of the drug in a cream base. It is helpful in selecting an effective drug or to evaluate the effectiveness of certain drugs in clinical practice.
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309
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Zhang MQ. [Ranitidine in the prevention of upper gastrointestinal tract hemorrhage following thermal injury]. ZHONGHUA ZHENG XING SHAO SHANG WAI KE ZA ZHI = ZHONGHUA ZHENG XING SHAO SHANG WAIKF [I.E. WAIKE] ZAZHI = CHINESE JOURNAL OF PLASTIC SURGERY AND BURNS 1991; 7:248-9, 316. [PMID: 1811837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper reports the use of Ranitidine in preventing upper gastrointestinal tract hemorrhage following thermal injury. In 12 hours after intravenous injection of Ranitidine, gastric pH was elevated from 3.25 +/- 0.26 to 5.16 +/- 0.47 (P less than 0.01) in twenty-one burn patients, with mean TBSA 62.6% +/- 17.2% (31%-87.5%), mean third degree BSA 41.4% +/- 18.3% (0-68%). The volume of gastric secretion was decreased from 15.81 +/- 4.4 ml to 2.85 +/- 0.9 ml. The free acid of gastric secretion was decreased from 25.74 +/- 4.42 mmol/L to 5.98 +/- 3.68 mmol/L (P less than 0.01). The total titratable acidity of gastric secretion was decreased from 44.76 +/- 5.76 mmol/L to 13.85 +/- 0.02 mmol/L (P less than 0.01). Three patients had occult blood in their gastric contents on admission, and it turned negative after Ranitidine therapy. However, during 1987-1988, the incidence of upper gastrointestinal tract hemorrhage of fifty-one patients with similar TBSA and third degree BSA burned was 21.6%. Changes in gastric secretion and lowered incidence of upper gastrointestinal hemorrhage after Ranitidine therapy suggest that Ranitidine may be effective in preventing upper gastrointestinal tract hemorrhage following thermal injury.
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310
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Zhang MQ, Haemers A. Quinolone antimicrobial agents: structure-activity relationships. DIE PHARMAZIE 1991; 46:687-700. [PMID: 1803382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The rapid growth in the quinolone research changed the whole face of the previous SAR concepts. So far structural modifications at all positions of the quinolone nucleus except the 4-oxo group have successfully lead to the discovery of potent antimicrobial agents. At position 1, ethyl and its bioisosteres such as fluoroethyl, methylamino, methoxy, etc, are optimal substituents while some groups with a tert.-carbon atom directly connected with N-1 position such as tert.-butyl, phenyl, etc. are also promising for the activity of the quinolone compounds. Steric bulk is no longer considered as the only factor which influences the activity of the compounds. However, it could only be answered by further research how big such steric bulk tolerance at position 1 would be and what is the precise role that the N-1 substituents play in the mechanism of action of the quinolones. Fluorination has been extensively employed as a modifying technique to almost all possible positions of the quinolone nucleus. While being maintained at C-6, a fluorine atom was also introduced to C-5 and C-8 to produce potent analogues. Fluorination of N-1 substituents, e.g., fluoroethyl, fluorophenyl, etc., and C-7 substituents, e.g. 2-((fluoromethyl)piperazinyl and fluorohomopiperazinyl, etc., yielded also a handful of potent quinolones. Amino-and chloro groups are found to be beneficial for positions 5 and 8, respectively. The "medium size" concept concerning the 7-substituents is no longer valid. Numerous potent quinolones with a "large" group substituted on position 7 have been discovered. A certain amount of free rotation in the 7-substituents appears to emerge as an important factor which influences the activity of the compounds. Some radical modifications in 7-substituents, e.g. C--C linkage between the nucleus and 7-substituents, afforded new insight into the SAR of quinolones. A planarity between the 4-oxo group and 3-carboxylic group may be important for binding to the DNA gyrase as demonstrated by a group of enolized isothiazoloquinolone derivatives. Further research will surely lead to the better understanding on the mechanism of action of quinolones as well as the discovery of analogues with better activity features, lower adverse effects and more favourable pharmacokinetic properties.
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311
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Leysen DC, Zhang MQ, Haemers A, Bollaert W. Synthesis of antibacterial 4-quinolone-3-carboxylic acids and their derivatives. Part 2. DIE PHARMAZIE 1991; 46:557-72. [PMID: 1665908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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312
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Zhang MQ, Levshin I, Vanden Berghe D, Haemers A. Synthesis and antibacterial evaluation of 1-(4-thiazolylmethyl)- and 7-(4-thiazolylmethyl)amino-substituted quinolones. Eur J Med Chem 1991. [DOI: 10.1016/0223-5234(91)90066-v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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313
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Zhang MQ. Zero-thickness membrane interface and Schrödinger equation. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 42:4588-4590. [PMID: 9904564 DOI: 10.1103/physreva.42.4588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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314
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Haemers A, Leysen DC, Bollaert W, Zhang MQ, Pattyn SR. Influence of N substitution on antimycobacterial activity of ciprofloxacin. Antimicrob Agents Chemother 1990; 34:496-7. [PMID: 2334166 PMCID: PMC171627 DOI: 10.1128/aac.34.3.496] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Ciprofloxacin analogs with various substitutions on the piperazine nitrogen were tested against several mycobacteria. In contrast to what has been found with other gram-positive and gram-negative bacteria, alkyl analogs such as N-isopropylciprofloxacin were shown to be significantly more active than ciprofloxacin. MICs of 0.125 microgram/ml against Mycobacterium tuberculosis were found.
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315
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Zhou Z, Yu MG, Xiao JY, Wang GY, Xie BW, Hu SX, Zhao SQ, Zhang MQ. [Studies on the introduction and cultivation of Kaempferia galanga L]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 1989; 14:11-4, 61. [PMID: 2506889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This paper reports a systematic survey of the biological character istics of K. galanga. As a result of investigations on plant density, planting season, fertilization, storage of maternal tubers in winter and qualitative analysis of tubers, etc, cultural measures have been brought forth that suit the local climatic conditions and thus give high yield and quality of products.
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316
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Jew JY, Williams TH, Gabella G, Zhang MQ. The intestine as a model for neuronal plasticity. ARCHIVES OF HISTOLOGY AND CYTOLOGY 1989; 52 Suppl:167-80. [PMID: 2479400 DOI: 10.1679/aohc.52.suppl_167] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
This study focuses on establishing the nature and extent of the changes that occur in gastroenteric innervation, specifically the myenteric plexus of the rat ileum, following an injury generated by experimental obstruction. A partial obstruction was accomplished by placing a cuff around the terminal portion of the ileum of the rat. Substantial hypertrophy of the enteric muscle wall occurred after 3-5 weeks. Light microscopic examination of the myenteric plexus revealed changes in the numbers of neuronal perikarya, ganglia and perikarya per ganglia; sizes and shapes of perikarya; and thicknesses of nerve fiber bundles. Using vasoactive intestinal polypeptide (VIP) and substance P light microscopic immunohistochemistry, we observed indications of transmitter accumulation in cell bodies and nerve fibers and reactive, degenerative and regenerative changes in axonal endings. Electron microscopic studies provided evidence for neuroplastic changes, as demonstrated by the appearance of reactive and regenerative, or growth, cones in the myenteric plexus.
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317
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Percus JK, Zhang MQ. One-dimensional inhomogeneous Ising model with periodic boundary conditions. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 38:11737-11740. [PMID: 9946059 DOI: 10.1103/physrevb.38.11737] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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318
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Zhang MQ. Supersymmetrical approach to critical dynamics of relaxational models. PHYSICAL REVIEW. B, CONDENSED MATTER 1987; 36:3824-3829. [PMID: 9943319 DOI: 10.1103/physrevb.36.3824] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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319
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Zhang MQ. [Clinical significance of tomography in congenital atresia of the external acoustic meatus]. ZHONGHUA FANG SHE XUE ZA ZHI CHINESE JOURNAL OF RADIOLOGY 1987; 21:225-7. [PMID: 2961542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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320
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Zhang MQ. Exact results on the steady state of a hopping model. PHYSICAL REVIEW. A, GENERAL PHYSICS 1987; 35:2266-2275. [PMID: 9898403 DOI: 10.1103/physreva.35.2266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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321
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Xiao XL, Li QY, Zhang MQ, Wang DY, Zhang LH. [A biogenetic synthesis of prostaglandin E1 methyl ester]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1986; 21:630-2. [PMID: 3811960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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322
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Kuang PG, Lang SY, Dai FL, Zhang DM, Zhang FY, Pu CQ, Hu YM, Zhang MQ. Studies of qingyangshen (root of Cynanchum otophyllum). III. Effect of qingyangshen on acetylcholine concentration in mouse brain. J TRADIT CHIN MED 1985; 5:267-70. [PMID: 3834241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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323
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Hu YM, Zhang MQ, Kuang PG, Lang SY, Zhong YL, Wang CL, Liang SQ. Studies of qingyangshen (root of Cynanchum otophyllum). I. Effect of qingyangshen on copper and zinc metabolism. J TRADIT CHIN MED 1985; 5:95-8. [PMID: 3851121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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324
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Liang CC, Xiong F, Yang KG, Chen SS, Jia PC, Zhang MQ, Zhao ZH. Hemoglobin GuiZhou or alpha 277(EF6)Pro----Arg beta 2, a new slow-moving hemoglobin variant observed in China. Hemoglobin 1984; 8:387-90. [PMID: 6548206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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325
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Tu YY, Ni MY, Zhong YR, Li LN, Cui SL, Zhang MQ, Wang XZ, Liang XT. [Studies on the constituents of Artemisia annua L. (author's transl)]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1981; 16:366-70. [PMID: 7246183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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326
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Zhang MQ. [Discussion on the errors of tomography (author's transl)]. ZHONGHUA FANG SHE XUE ZA ZHI CHINESE JOURNAL OF RADIOLOGY 1980; 14:120-3. [PMID: 6451390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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