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Biomedical subjects

W B Sun

Publications and source records attributed to W B Sun.

6 recordsLinked to original sources
PubMed2006

Origin and phylogeographical structure of Chinese cattle.

Complete mitochondrial D-loop sequences of 231 samples were used to explore the origin and genetic diversity of Chinese cattle. Phylogenetical analysis of these sequences revealed both Bos taurus and Bos indicus mitochondrial types in Chinese cattle. Four of the previously identified mitochondrial DNA lineages (T1-T4) were identified in the Bos taurus type, including lineage T1, which was found for the first time in Chinese cattle. Two lineages (I1 and I2) were identified in the Bos indicus type. Our results support the suggestion that the Yunnan-Guizhou Plateau is the domestication site of Chinese zebu. We also found evidence that Tibetan cattle originated from taurine and zebu cattle. The distribution pattern of Chinese cattle breeds was closely related to the geographical and climatic background. It was possible to divide Chinese cattle in this study into two major groups: northern and southern cattle.

Animals↗
PubMed2000

The surgical treatment of isolated left-sided hepatolithiasis: a 22-year experience.

BACKGROUND: Various therapeutic methods are used in isolated left hepatolithiasis (ILH), and long-term results are not as satisfactory as they should be. METHODS: A retrospective analysis of 128 patients with ILH who were treated in our center over the last 22 years was undertaken to address patient age, gender, preoperative evaluation, operative findings, treatment modalities, and postoperative courses. RESULTS: Sixty of the 128 patients were male and 68 were female, with a mean age of 42 years (range, 16-72 years). Among these patients, most (81%) had stones in both left external hepatic duct (LEHD) and left medial hepatic duct; in contrast 13 patients (10%) had stones only in the LEHD, and 7 patients (6%) had stones only in the left hepatic duct. Concomitant strictures were present in the left hepatic duct, left medial hepatic duct, and LEHD in 60%, 76%, and 82%, respectively, most of which were severe. When compared with left lateral segmentectomy, left hepatic lobectomy had a lower rate of residual stones (4% vs 22%; P < .01). Residual/recurrent stones and ductal strictures were the 2 most common causes that affected the long-term results. Before June 1996, left lateral segmentectomy was performed more frequently than left hepatic lobectomy (59% vs 12%; P < .01); after June 1996, left hepatic lobectomy was performed more frequently (77% vs 13%; P < .01). Although there were no differences in length of operation, intraoperative bleeding, and postoperative complications, residual stones were more common after left lateral segmentectomy. CONCLUSIONS: Left hepatic lobectomy appears to be the most effective treatment for selected patients with ILH, if other operative procedures cannot remove all the related lesions, which include stones, dilation, stricture, or potential cholangiocarcinoma.

Adolescent↗
PubMed2000

[Effect of dissolved oxygen on mutanolysin fermentation].

Effects of several parameters relating to dissolved oxygen(DO) on mutanolysin fermentation were studied. The experiment using shake flasks shows that the medium volume and shaker agitation speed affect the production of mutanolysin. At the same time, the agitation rate together with aeation rate has effects on DO in fermentor. Mutanolysin fermentation was affected by DO greatly. Oxygen is a key restricted factor in mutanolysin fermentation. It affects the metablism and physiological action of Streptomyces globisporus S186. Whatever the DO is excessive high or low, it won't benefit the mutanolysin production. If DO is super, S. globisporus S186 will grow luxuriantly but do not produce mutanolysin, while if DO is lower, the S. globisporus S186 won't grow well even not to produce mutanolysin. During the course of fermentation, the DO changed regularly. It is similar to many antibiotic fermentation and some amino acid fermentation. As S. globisporus S186 grow in exponential phase, DO begin to decrease rapidly from 6 h and get to the lowest point at 40 h or so. Subsequently mutanolysin starts to be produced. DO rises again from 90 h. The key technoloyg of oxygen control in the fermentation is to keep the DO at a suboptimum level. In order to get a high mutanolysin yield, during the culture in fermentor the agitation rate and aeration rate should be kept at 200 r/min and 1:0.8(V:V) respectively.

Endopeptidases↗
PubMed2000

[Staining of complete denture: a preliminary clinical study]

OBJECTIVE:To study the relation between staining of complete denture and drinking tea, coffee and smoking, and to evaluate the result of denture cleaning agent on removing stain of complete denture.METHODS:A survey of 176 patients with complete dentures were carried out, which included the history of drinking tea, coffee and smoking, the use of denture-cleaning agent and the times of daily use. Statistical analysis was performed to determine the relationship between staining of denture and the above factors. RESULTS:The results showed (1)The longer the complete denture was weared, the more serious the staining. (2)Drinking tea and smoking were the main causes for denture staining. (3)Daily use of cleaning agent can effictively remove stain of denture. CONCLUSION:Change of life habit(drinking less tea and stop of smoking) and daily use of cleaning agent can reduce denture staining.

Journal Article↗