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Biomedical subjects

G Y Yin

Publications and source records attributed to G Y Yin.

At least 19 recordsLinked to original sources
PubMed2005

Generation of a single-cycle optical pulse.

We make use of coherent control of four-wave mixing to the ultraviolet as a diagnostic and describe the generation of a periodic optical waveform where the spectrum is sufficiently broad that the envelope is approximately a single-cycle in length, and where the temporal shape of this envelope may be synthesized by varying the coefficients of a Fourier series. Specifically, using seven sidebands, we report the generation of a train of single-cycle optical pulses with a pulse width of 1.6 fs, a pulse separation of 11 fs, and a peak power of 1 MW.

Journal Article↗
PubMed2003

Quasiperiodic Raman technique for ultrashort pulse generation.

We report the experimental demonstration of a new Raman technique that produces 200 sidebands, ranging in wavelength from 3 microm to 195 nm. By studying multiphoton ionization of nitric oxide (NO) molecules, we show mutual phase coherence among 15 visible sidebands covering 0.63 octaves of bandwidth.

Journal Article↗
PubMed2001

Femtosecond light source for phase-controlled multiphoton ionization.

We describe a femtosecond Raman light source with more than an octave of optical bandwidth. We use this source to demonstrate phase control of multiphoton ionization under conditions where ionization requires eleven photons of the lowest frequency of the spectrum or five photons of the highest frequency. The nonlinearity of the photoionization process allows us to characterize the light source. Experiment-to-theory comparison implies generation of a near single-cycle waveform.

Journal Article↗
PubMed2000

Raman generation by phased and antiphased molecular states.

We use molecular deuterium and two driving lasers to demonstrate collinear generation of mutually coherent equidistant sidebands, covering 50 000 cm(-1) of spectral bandwidth and ranging from 2.94 microm to 195 nm in wavelength. The essential idea is the adiabatic preparation of a single, highly coherent (|rho(ab)| = 0.33) molecular eigenstate.

Journal Article↗
PubMed1996

[Clinical study on the piweiping capsule in treating patients with metaplasia of gastric mucosa].

One hundred and forty-three patients were diagnosed as chronic superficial atrophic gastritis of gastric antrum or with metaplasia by means of gastroscopic observation with pathological biopsy examination. They were divided into 4 types (the Spleen-Stomach Cold-Deficiency type, Disharmonious of Liver and Stomach type, Spleen-Stomach Yin Deficiency type and Spleen Deficiency with Qi-Stagnation type) and subdivided according to treatment into two groups, 75 patients of treatment group of above-mentioned 4 types were treated with Piweiping capsule (PWPC) I, II, III, IV respectively, 68 patients of control group were all treated with Sanjiu Weitai (SJWT). After 3-6 months of treatment, the improvement of gastric mucosa cyclic adenosine monophosphate, deoxyribonucleic acid, 3H-thymopyrimidine nucleoside and lymphocyte transformation of treatment group were all superior to that of control group, P < 0.05-0.001. The curative rate and total effective rate of symptomatic effect of treatment group were 49.3% and 92.0%, while at intestinal metaplasia of treatment group were 45.3% and 62.7%. As in control group, they were 29.4%, 67.6%, 10.3% and 29.4% respectively. The difference between two groups was significant, P < 0.001. These results suggested that the PWPC could reverse the intestinal metaplasia through improving the gastric cAMP, DNA and strengthening the cellular immunity and the effect would be enhanced when the treatment was based on syndrome differentiation.

Adult↗
PubMed1995

The developmental pattern of Brca1 expression implies a role in differentiation of the breast and other tissues.

We have examined the developmental expression of the murine breast and ovarian cancer susceptibility gene, Brca1, to investigate its role in the control of cell growth and differentiation. Specifically, we have analysed Brca1 expression during embryonic development, in adult tissues, and during postnatal mammary gland development, particularly in response to ovarian hormones. Our results suggest that Brca1 is expressed in rapidly proliferating cell types undergoing differentiation. In the mammary gland, Brca1 expression is induced during puberty, pregnancy, and following treatment of ovariectomized animals with 17 beta-estradiol and progesterone. These observations imply that Brca1 is involved in the processes of proliferation and differentiation in multiple tissues, notably in the mammary gland in response to ovarian hormones.

Animals↗
PubMed1995

Mouse Brca1: localization sequence analysis and identification of evolutionarily conserved domains.

The human genes BRCA1, conferring susceptibility to early-onset breast and ovarian cancer, has recently been isolated. Here we describe isolation of cDNAs, sequence analysis, and genomic localization of the murine homolog, Brac1. The mouse cDNA sequence predicts a protein of 1812 amino acids; a number of small gaps account for the 51 fewer residues in the mouse protein relative to human BRCA1. While the predicted mouse and human proteins display on the whole a high level of homology (58% identity, 73% similarity), the regions of greatest homology are at the respective amino and carboxyl termini. Most reported disease-associated missense mutations in human BCRA1 occurred within these more highly conserved terminal regions. A predicted zinc-building RING finger domain near the amino terminus lies within a 50 amino acid stretch that is perfectly conserved in both species. The strong conservation during mammalian evolution argues for the importance of this domain, perhaps mediating a role for BRCA1 in DNA and/or protein binding. We have also identified a conserved highly acidic domain in the carboxyl terminal half of the BCRA1 protein resembling acidic transactivation domains of certain transcription factors. Using an interspecific backcross panel, Brca1 was mapped to a region of mouse chromosome 11 that exhibits conserved linkage with 17q21. The sequence and isolated cDNAs will provide useful reagents for studying the expression of Brca1 in the mouse, and for testing the importance of the evolutionarily conserved domains.

Amino Acid Sequence↗
PubMed1995

[Effect of zhuchun pill on immunity and endocrine function of elderly with kidney-yang deficiency].

After randomly dividing 45 elderly males with Kidney-Yang Deficiency into Zhuchun Pill (ZCP) group and placebo (starch capsule) group by single blind method, and treating them for 3 months, we found that ZCP could greatly improve the main symptoms of Kidney-Yang Deficiency, P < 0.01 by comparison with control group: the 3H-TdR lymphocyte transformation (3H-TdR LCT) rate, level of serum C3, IgA, IgD, IgG & IgM went up (P < 0.01); contents of plasma adrenocortical hormone (ACTH), testosterone (T) and cyclic adenosine monophosphate (cAMP) increased (P < 0.01-0.001): the level of superoxide dismutase (SOD) in serum also increased while lipid peroxide (LPO) in plasma decreased (P < 0.01). But for control group, there were no remarkable changes after treatment, so it revealed that the improvement of Kidney-Yang Deficiency by ZCP is realized through regulating the organism's immunity and endocrine function as well as through scavenging the free radical agents.

Adjuvants, Immunologic↗
PubMed1995

[Study on mitochondrial ultrastructure, trace elements and correlative factors of gastric mucosa in patients with spleen deficiency syndrome].

Eighty-eight gastropathic patients with Spleen deficiency syndrome by using transmission electron microscope (TEM), X-ray energy disperse analysis system (EDAX), histochemical staining and radioimmuno methods were examined. The authors found that the gastric mucosa cAMP, SOD level, the quantity of mitochondria and its crista, the ratio of diameter between ventricle and cavity of mitochondria and the content of Zn, Cu of mitochondria were reduced in the trend of healthy control group, Spleen Qi deficiency group, Spleen deficiency with Qi stagnation group; chronic superficial gastritis group, chronic atrophic gastritis group, gastric cancer group: complete small intestinal metaplasia group, incomplete small intestinal metaplasia group, complete colonic intestinal metaplasia group, incomplete colonic intestinal metaplasia group (P < 0.05-0.001). While the degeneration rate of mitochondria, the Cu/Zn ratio of mitochondria, the metaplasia rate of gastric, the rate of incomplete colonic intestinal metaplasia and the content of serum LPO were increased in the above turn. It is suggested that the comprehensive effect of the degeneration of mitochondria and the quantitative changes of its correlative factors is the physiopathologic base for inducing Spleen deficiency disease, gastric mucosa metaplasia and canceration. Much attention must be paid in clinic to the cancerization trend of gastric disease with Spleen deficiency syndrome.

Adult↗
PubMed1989

[Clinical significance of the measurement of trace elements in the gastric mucosa and their oxides in patients with spleen diseases and gastric cancer].

The gastric mucosa trace elements and oxides were investigated with X-ray energy disperse analysis system in 41 cases of gastric disease due to Spleen deficiency. The differences in the change of the quantity of Zn, Cu, ZnO and CuO were very significant (P less than 0.05-0.001) in the gastric mucosa between normal area and focal area, between Spleen Qi deficiency and Spleen deficiency with Qi stagnation, and between benign gastric disease and gastric cancer. The experiments showed that: (1) The trace elements in the organism form its own system, the values being within the relatively constant scope. (2) The ratios of Zn/ZnO and Cu/CuO reflected "the rate of effectual utility" of Zn and Cu. (3) There was a very close internal relation between Spleen deficiency with Qi stagnation and gastric cancer. (4) The quantitative changes of Zn, Cu, ZnO, CuO, Zn/ZnO and Cu/CuO were related to pathologic change and the TCM syndrome pattern, and is worthy of further research.

Adult↗
PubMed1989

[Research on the fundamental factors and conditions of gallstone formation].

The authors applied scanning electron microscope with synchronization of EDAX to detect the ultrastructure of gallbladder mucosa, metallic elements and their oxides, to observe the bacteria of the core of the gallstone; applied cholecystokinin to observe the effects of abnormal gallbladder contraction on stone formation; applied biochemical, immunological criteria to determine the association between liver and gallbladder diseases and gallstone; applied scanning electron microscope to compare the analysis of mechanical structure of gallstone. According to the results of research, the authors conclude: (1) The basic condition of the formation of the gallstone was the disturbance of physiological reaction of "integration" and "homeostasis" of liver-biliary system. (2) The essential factor of the formation of gallstone was the infection of liver-biliary system. (3) The formation of the gallstone structure was caused by changed physical and chemical mechanics of bile. (4) The synchronization treatment of liver-biliary was the principle of preventing and treating gallstone.

Adult↗