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Biomedical subjects

G Xu

Publications and source records attributed to G Xu.

At least 523 records · Page 29Linked to original sources
PubMed1992

Students' ratings of otolaryngology clerkship activities: the role of residents.

The present study was conducted with a sample of junior medical students at Jefferson Medical College to investigate the factors that influence students' overall satisfaction with the otolaryngology clerkship. The most important factor related to their overall satisfaction in the clerkship was their experience with residents, followed by experience with attending physicians, quality of rounds, and of lectures. The number of patients the students encountered, and number of rounds and lectures were deemed less important. Based on these findings, the authors of this paper concluded that the residents' role in teaching should be emphasized and students' satisfaction with the otolaryngology clerkship may be enhanced by developing residents' skills in teaching students.

Attitude↗
PubMed1992

Nutritional and physiological factors affecting germination of heterothallic Saccharomyces cerevisiae ascospores.

Saccharomyces cerevisiae strain AP-3 was examined with respect to those nutritional requirements and physiological conditions which influence its germination rate. It was found that glucose as a carbon source supported the most rapid rate of germination for this heterothallic strain. In contrast, strain AP-3 spore germination was supported the least by the carbon sources potassium acetate and lactose. Of the nitrogen sources tested in culture medium containing glucose, the complex nitrogen sources peptone and casein hydrolysate appeared to be capable of stimulating germination better than a control culture containing ammonium sulphate. None of the amino acids screened were found to stimulate strain AP-3 germination compared with ammonium sulphate. The optimal culture medium pH for ascospore germination was 4.5 although spore germination could still be initiated by glucose between pH 3.0 and pH 7.5. Germination initiation by glucose was observed over a temperature range from 25 degrees C to 50 degrees C, but the optimal temperature appeared to be 40 degrees C.

Hydrogen-Ion Concentration↗
PubMed1992

[Textual study on traditional Chinese drugs caodoukou and baidoukou].

Through a critical study of herbalogy, it is concluded that the mature seeds of Alpinia zermubet were used as caodoukou in ancient times. The original plant of Yutao recorded in Zhiwu Mingshi Tukao may be the species of Alpinia katsumadai. Baidukou used in ancient times may be the seeds of Alpinia katsumadai found in the south of China, or Amomum compactum and Am. kravanh imported from foreign countries.

Drugs, Chinese Herbal↗
PubMed1991

A comparison of Jefferson Medical College graduates who chose emergency medicine with those who chose other specialties.

Fifty-three graduates of Jefferson Medical College who chose emergency medicine (EM) over the decade from 1981 through 1990 were compared with the other graduates of that school during that decade who chose other specialties, using the database of the school's longitudinal study of its students. As seniors, those who chose EM had the highest debt of seniors going into any specialty. However, the mean peak income they expected was higher than that expected by the other nonsurgeons, although it was below that expected by the surgeons. The EM group compared favorably with those who chose other specialties in terms of their academic records and had the highest mean Part III score on the National Board of Medical Examiners examination of any of the groups studied. The students who chose EM also indicated their great willingness to see patients from low-income households, and were willing to spend more of their practice time serving these groups than were the students who chose the other specialties. The authors discuss these findings as related to the nature of EM and medical school graduates' choices of specialties.

Adult↗
PubMed1991

[Experimental study of Syrian hamster embryo cell transformation induced by chrysotile fibers and coal dusts in vitro].

We studied the Syrian hamster embryo (SHE) cell transformation by focus assay for detecting the carcinogenicity of chrysotile asbestos fibers collected from Sichuan Xinkang Asbestos Mine and particulate coal dusts from Jiayang Coal Mine. Both these mines belong to Sichuan Province. Results showed that transformed foci were found in the methylcholanthrene group and in the two asbestos dosing groups (8 micrograms/ml and 4 micrograms/ml), whereas no transformed foci were noted in the coal dust groups and no spontaneous transformation in the negative control groups. Morphologically, the transformed foci were documented by light and electronmicroscopy. Significant differences between the positive transformed groups and the negative control groups were demonstrated by statistic analysis. The results indicate that Sichuan Xinkang chrysotile asbestos fibers are of carcinogenic potentiality, and Jiayang coal dusts do not induce transformation in SHE cells.

Animals↗
PubMed1991

[Studies on the quality of fructus Cnidii--comparison of antibacterial action].

Comparative studies on antibacterial and antifungal action of the fruits of C. monnieri from four habitats and two other species of Cnidium showed they had inhibitory potency to some bacterial and fungi in vitro. C. monnieri and C. salium were more effective than C. dahuricum in antibacterial activities. C. monnieri had higher antifungal effect than C. salium and C. dahuricum.

Bacteria↗
PubMed1991

[Further investigation into the recurrent causes of post-vidian neurectomy and the feasibility of treating vasomotor rhinitis by surgery].

The authors had found that there were parasympathetic nerve fibres in the anterior ethmoid nerve and also cholinergic microganglia were present in the inferior turbinate of humans by the histochemical method of acetylcholinesterase (AChE). These structures had an important role in the pathogenesis of vasomotor rhinitis and also might be used to explain the recurrence of patients who had undergone vidian neurectomy. The authors put forward a new suggestion in the treatment of vasomotor rhinitis by a combination of vidian neurectomy, anterior ethmoid neurectomy and inferior turbinectomy. But the surgical method would be the last selection in the treatment of vasomotor rhinitis.

Adult↗
PubMed1991

[Quality of tuberous root of Liriope spicata (Thunb.) Lour. var. prolifera Y.T.Ma and Ophiopogon japonicus (L.F.) Ker-Gawl.--comparison of immune function].

This paper deals with comparative study on the immune function of the tuberous root of Liriope spicata var. prolifera and Ophiopogon japonicus. The results showed that the aqueous extract of both species mentioned above could increase obviously the spleen weight (immunity organ) of mice, enhance the clearance rate of iv charcoal particles in mice and antagonize remarkably the leukopenia caused by cyclophosphamide.

Animals↗
PubMed1991

[Textual and herbal studies on shashen and qini (Adenophora spp.)].

This paper reports the origins of the Chinese traditional drugs nanshashen and beishashen, as well as the original plants of shashen, xingyeshashen, xiyeshasen and qini recorded in the bencaological works of the past dynasties. Our study shows that shashen is Adenophora stricta, both xingyeshashen and qini are A. hunanensis and xiyeshashen is A. paniculata.

Drugs, Chinese Herbal↗
PubMed1991

[The regulating effect of electroacupuncture on gastroenteric electric activity in guinea pigs of peripheral vomiting].

Acute experiments were performed on 20 guinea pigs. The animals were divided at random into four groups of five each: the non-acupuncture group for control and three electroacupuncture groups (EA-I, EA-II, EA-III). Four pairs of platinum-wire electrodes were implanted under serosa of the antrum and corpus, duodenum, jejunum. The gastroenteric electric activity (GEA) was recorded in conscious and fasting state. Needling was applied at position 1 cm below the knee, corresponding to Zusanli. The peripheral vomiting model was established by infusion of CuSO4 into the stomach. Observation was made with regard to latency of vomiting induced by infusion of CuSO4, duration of the symptom, number of fits in the first five minutes after the attack began, and the variation of amplitude and frequency of GEA. The results were as follows: (1) The GEA of normal guinea pigs showed regular cyclic changes. After latency of 3.7 seconds following the infusion, symptom of vomiting began appear. The GEA returned to normal after latency of 60 minutes. (2) During vomiting, the GEA was characterized by a series of spikes which were seen more obviously in the antrum and corpus; during serious fits of vomiting, duodenum and jejunum were involved. The GEA showed disordered and quicker rhythm with higher amplitude and frequency. (3) EA could not affect the latency of the peripheral vomiting, but it could shorten the duration of the symptom. Results of group EA-II (p less than 0.001) showed EA could reduce the number of fits during the first five minutes; results of group EA-I (p less than 0.01) showed that EA could lower the amplitude and frequency of the GEA (p less than 0.05) that rose during vomiting.(ABSTRACT TRUNCATED AT 250 WORDS)

Acupuncture Therapy↗
PubMed1991

[Transnasal endoscopic sinus surgery].

The endoscopic sinus surgery is probably the most exciting topics in rhinology. Not only is the technology new, but the approach to sinus disease has changed dramatically. In this paper, we tried to present how sinus endoscopy can be applied to the treatment of sinus diseases and more radical forms of sinus surgery. Three kinds of surgical procedures were performed, they were the functional anterior ethmoidectomy, total ethmoidectomy, and total sphenoethmoidectomy for treatment of chronic ethmoid sinusitis (2 cases), polysinusitis with polyps (16 cases), and pansinusitis with polyps (5 cases). The results showed that the pus disappeared in 14 cases (60.8%), the dizziness and headache improved in 22 cases (95%), the smell improved in 14 cases (70%). There were 4 complications: nasolacrimal duct injury in one, and lamina papyracea injury in three. All of them recovered after management.

Adult↗
PubMed1990

Deletions and a translocation interrupt a cloned gene at the neurofibromatosis type 1 locus.

Three new neurofibromatosis type 1 (NF1) mutations have been detected and characterized. Pulsed-field gel and Southern blot analyses reveal the mutations to be deletions of 190, 40, and 11 kb of DNA. The 11 kb deletion does not contain any of the previously characterized genes that lie between two NF1 translocation breakpoints, but it does include a portion of a rodent/human conserved DNA sequence previously shown to span one of the translocation breakpoints. By screening cDNA libraries with the conserved sequence, we identified a number of cDNA clones from the translocation breakpoint region (TBR), one of which hybridizes to an approximately 11 kb mRNA. The TBR gene crosses at least one of the chromosome 17 translocation breakpoints found in NF1 patients. Furthermore, the newly characterized NF1 deletions remove internal exons of the TBR gene. Although these mutations might act by compromising regulatory elements affecting some other gene, these findings strongly suggest that the TBR gene is the NF1 gene.

Adult↗