Widespread aeolian sediments have been found in the middle reaches of the Yarlung Zangbo River, China, The grain-size characteristics of sediments from Cha＇er Section in the area were analyzed. The results show that ...Widespread aeolian sediments have been found in the middle reaches of the Yarlung Zangbo River, China, The grain-size characteristics of sediments from Cha＇er Section in the area were analyzed. The results show that the section include one stratum of paleo-mobile dunes, four strata of paleo-semi-fixed dunes, two strata of paleo-fixed dunes, one stratum of sandy immature soils. The paleo-mobile and paleo-semi-fixed dune sand in this section are similar to modem aeolian sand in either grain-size composition or Mz and c distribution. Compared the above types of dunes each other, the content of sand substance decreases, while the content of silt and clay increases for paleo-fixed dunes and sandy immature soils. Combined with age data for each stratum, the analysis shows that these strata are the products of climate changes and the evolution of aeolian landforms. The evolutionary sequence of the paleoclimate and of aeolian activities in the valley since 8600 yr B.P. reveals four stages： 8600-5700 yr B.P., when the paleoclimate was cold and dry, with strong winds, thereby activating dunes; 5700-3600 yr B.P., when it was warm and wet, with weak winds, causing dunes to undergo soil-forming processes; 3600-1900 yr B.P., when climate shifted from cold-dry with strong winds to warm-wet with weak winds, and activated dunes were fixed again; and 1900 yr B.P. -present, when the climate became fine, with weak winds, fixing dunes again.展开更多
BACKGROUND Solitary rectal ulcer syndrome(SRUS)is a rare rectal disorder characterized by bloody mucus in the stool,difficulty in defecation,pain,and anal swelling.To date,the etiology of this syndrome remains not wel...BACKGROUND Solitary rectal ulcer syndrome(SRUS)is a rare rectal disorder characterized by bloody mucus in the stool,difficulty in defecation,pain,and anal swelling.To date,the etiology of this syndrome remains not well understood and the diagnosis is frequently confused with other disorders,making treatment a clinical challenge.CASE SUMMARY A 50-year-old woman presented to our hospital with a 40-d history of bloody mucus in the stool and anal swelling.SRUS was suspected.Rectoscopy revealed a large,severe ulcerous lesion.Histologically,the lesion was characterized as chronic ulcer without clear tumor cells,and the final diagnosis of SRUS was made.The patient was treated with Chinese medicine therapy,with administration of Tong Xie Yao Fang.After 3 wk of treatment,the symptoms improved significantly.At 2-mo follow-up,rectoscopy in a local hospital showed healed ulcer scars without obvious protrusion 3 cm from the anal verge.CONCLUSION Chinese medicine therapy represents a potential treatment of SRUS with predominant rectal bleeding,mucinous discharge,and anal swelling pain.展开更多
基金Under the auspices of National Natural Science Foundation of China (No. 40671185)National Key Technologies R&D Program of China (No. 2006BAD26B03)
文摘Widespread aeolian sediments have been found in the middle reaches of the Yarlung Zangbo River, China, The grain-size characteristics of sediments from Cha＇er Section in the area were analyzed. The results show that the section include one stratum of paleo-mobile dunes, four strata of paleo-semi-fixed dunes, two strata of paleo-fixed dunes, one stratum of sandy immature soils. The paleo-mobile and paleo-semi-fixed dune sand in this section are similar to modem aeolian sand in either grain-size composition or Mz and c distribution. Compared the above types of dunes each other, the content of sand substance decreases, while the content of silt and clay increases for paleo-fixed dunes and sandy immature soils. Combined with age data for each stratum, the analysis shows that these strata are the products of climate changes and the evolution of aeolian landforms. The evolutionary sequence of the paleoclimate and of aeolian activities in the valley since 8600 yr B.P. reveals four stages： 8600-5700 yr B.P., when the paleoclimate was cold and dry, with strong winds, thereby activating dunes; 5700-3600 yr B.P., when it was warm and wet, with weak winds, causing dunes to undergo soil-forming processes; 3600-1900 yr B.P., when climate shifted from cold-dry with strong winds to warm-wet with weak winds, and activated dunes were fixed again; and 1900 yr B.P. -present, when the climate became fine, with weak winds, fixing dunes again.
基金Supported by the Start-up Fund from Beijing University of Chinese Medicine,No.1000061020044
文摘BACKGROUND Solitary rectal ulcer syndrome(SRUS)is a rare rectal disorder characterized by bloody mucus in the stool,difficulty in defecation,pain,and anal swelling.To date,the etiology of this syndrome remains not well understood and the diagnosis is frequently confused with other disorders,making treatment a clinical challenge.CASE SUMMARY A 50-year-old woman presented to our hospital with a 40-d history of bloody mucus in the stool and anal swelling.SRUS was suspected.Rectoscopy revealed a large,severe ulcerous lesion.Histologically,the lesion was characterized as chronic ulcer without clear tumor cells,and the final diagnosis of SRUS was made.The patient was treated with Chinese medicine therapy,with administration of Tong Xie Yao Fang.After 3 wk of treatment,the symptoms improved significantly.At 2-mo follow-up,rectoscopy in a local hospital showed healed ulcer scars without obvious protrusion 3 cm from the anal verge.CONCLUSION Chinese medicine therapy represents a potential treatment of SRUS with predominant rectal bleeding,mucinous discharge,and anal swelling pain.
