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Several molecular simulation methods were integrated to investigate the detailed binding process of allophanate to allophanate hydrolase and predict their stable complex structure. The optimal enzyme-substrate complex conformation demonstrates that along with Arg307 and Tyr299, Gly124 is also one of the key anchor residues in the stable complex. The energetic calculation suggests the existence of an intermediate state in the enzyme-substrate binding process. The further atomic-level investigation illuminates that Tyr299, Arg307 and Ser172 can stabilize the substrate in the intermediate state. By this token, the residues Arg307 and Tyr299 function in both binding process and getting stable state.

Hybrid zone is a very critical concept within the evolutionary biology, because it would offer us a better insight to understand the evolutionary role of gene flow and hybridization based on the cline model. This minireview presents an expatiation of history perspectives and research developments upon basic concepts including hybrid zones, hybridization, hybrid and its the genetic cline model. Moreover, by figuring out the existing problem around the hybrids within conservative theory and practices, it suggests that the theory of hybrid zone be introduced into conservation biology and it would be provide a broader and more open theoretical background for conservative research and practices.

Fecal indicators of nutritional status of wild ungulates were less constrained than that of blood, rumen contents, or urine analyses. Thus, we compared the nitrogen and fiber concentrations of feces with those of the rumen contents of Mongolian gazelles (Procapra guttrurosa) in Hulunbeier Grassland. Rumen contents and fecal nutritional concentrations varied in different seasons. Dietary nitrogen concentrations only increased linearly with increase nitrogen concentration in fecal in winter. There was a positive correlation between rumen NDF (neutral detergent fiber) and fecal NDF concentrations. But the regression coefficient was small (r=0.3917). There was a significant regression equation between rumen contents ADF (acid detergent fiber) and fecal ADF concentrations, as well as ADL (acid detergent lignin) concentrations. Nitrogen concentration was found to be negatively correlated with NDF, ADF, and ADL concentrations both in rumen and in fecal compositions. Our data suggest that fecal nitrogen, ADF, ADL concentrations may assess winter dietary qualities that are in protein, crude fiber and lignin concentrations for Mongolian gazelles.

The stomach compartments of 51 Mongolian gazelles (Procapra guttrurosa) were weighed and the data were compared with total body weight. The total tissue weights ranged from 2.70% to 2.82% of body weight. Rumens were the heaviest, occupying about 75% of the total stomach, followed by reticulums (9%–11%), abomasums (8%–10%) and omasums (4%–6%). The weights of rumens were directly proportional to body weights and weights of omasums and abomasums were inversely related to body weights. Stomachs of the Mongolian gazelle were of the “mixed feeder” in terms of total weight and contribution of each compartment.

The authors discussed the administrative system of export quota and its method of calculation in the international wildlife trade. Three methods for determining wildlife export quota in China was put forward, based on the trend and status, domestic use, and historical export of wildlife resources. They include the single factor method, the double factor method, and the multiple factor method. In addition, the approaches and measures to establish and carry out the administrative system of wildlife export quota in China were discussed in this paper.

Four isozymes, such as Malate dehydrogenase (MDH), Aichol dehydrogenase (ADH), Peroxidae (POD) and Esterase (EST) in six tissues (heart, liver, kidney, muscle, eye, gonad) of Martes zibellina L., were analyzed by means of vertical polyacrylamide gel electrophoresis (PAGE). The results indicated that the zymograms of these four isozymes in different tissues were different from each other, i.e. there existed apparent tissue-specificity in these isozymes in Martes zibellina L.. Characteristic enzyme band was found both in POD zymogram and in EST zymogram. Moreover, the characteristic enzyme band in POD isozyme would be of some value to sexual identification of Martes zibellina L.

The accuracy of three methods (pellet group count, inverse [me transect method and track count) for estimating the density of ungulate population was assessed, based on a wapiti population with the known size in the enclosure of 500 hm^2 on Tonghe Hunting Farm, Heilongjiang province, China, during 1992-1993. The estimation of population density using the pellet group count method was the closest to the actual value, whereas the density of the wapiti population was underestimated by the inverse line transect method and overestimated by the track count method. No significant difference existed between the estimated and actual values for the pellet group method and the inverse line transect method, but the significant difference was found for the track count method. Therefore, it is suggested that the pellet group method should be given the priority in the survey of ungulate population abundance in practice.

Six commonly used restriction endonucleases (REs) (Acc I, Ban II, EcoR I, Hind III, Sac I, Sca I) were tested for their ability to directly digest DNA completely in the Polymerase Chain Reaction (PCR) buffers. The results showed that: with the requirement for additional magnesium supplemented as activator, REs, except EcoR I appeared star activity, completely digested unmethylated lambda DNA after overnight incubation in PCR buffer and functioned as equally well as in recommended Restriction Enzyme Buffer provided with each enzyme; all REs tested completely digested PCR products in PCR buffer, it implied digestion of PCR products may often be performed directly in the PCR tube without the requirement for any precipitation or purification steps; and the concentration of MgCl2 from 2.5 mmol·L−1 to 10 mmol·L−1 did not significantly affect activity of REs in PCR buffer. This simplified method for RE digestion of PCR products could have applications in restriction fragment length polymorphism (RFLP) analysis and single-stranded conformational polymorphism (SSCP) analysis of large PCR products. However, usage of this procedure for cloning applications needs further data.

There are three species of bears in China, brown bear (Ursus arctos), black bear (Selenarctos thibetanus) and sun bear (Helarctos malayanus). From 1991 to 1994, the investigation of bears organized by CWCA (China wildlife Conservation Association) was conducted in 22 provinces of China. The results showed that the distribution area of bears had been changed from the continuous distribution to fragmentary. The distribution areas of three species were limited to the area of 2591427 km2, and the total number of population was reduced to 61686. The distribution area of black bear was 625086 km2; the population size was 46528; average density was 0.0714/km2. The distribution area of brown bear was 1956691 km2; the population size was 14783; average density was 0.0076/km2. The distribution area of sun bear was 9650 km2; the population size was from 350 to 400. There are 396 bear farms in China and the 6688 bears are being reared on these bear farms 94.4% of them is black bears (3612); 4.5% of them is brown bears (300); 1.1% of them is sun bears (10). The management of bears in China was discussed in this paper.

From March to August in 1993 and 1994, we studied foraging strategies of rufous-backed shrike in Nushanhu in Anhui province. The shrikes mainly forage in farmland and uncultivated land. All the food in breeding period are animals. In different breeding stages, food composition had changes. Three types of foraging behavior were SP (Searching and Pecking), HP (Hiding and Pouncing) and FP (Flying and Pursing). FF and FSR change in opposed direction during breeding period. At early breeding period, the shrikes had hoarding behavior.

The study on winter food constitution of Mongolian gazella (Procapra gutturosa) was conducted in Hulunbeir grassland(Xinbarhuyou Banner, Hulunbeir League, Inner Mongolia) from spring 1994 to summer 1995. With microhistological analysis technique of feces, 21 plant species were identified to be availlable for Mongolian gazella as forage in winter and their nutritive trait were analyzed. Some foraging behavior of Mongolian gazella were also discribed.