Xingcuo lake,a closed one,is situated in eastern Tibetan Plateau.There are abundant snail shells Gy-raulus sibirica in its sediments.Here we display the determining results ofδ 13 C,δ 18 O in shell Gyraulus sibirica...Xingcuo lake,a closed one,is situated in eastern Tibetan Plateau.There are abundant snail shells Gy-raulus sibirica in its sediments.Here we display the determining results ofδ 13 C,δ 18 O in shell Gyraulus sibirica continuous-ly preserved in Xincuo Lake sediment s in the recent 50years.And by coupling the indexes ofδ 13 C,δ 18 O and instrumen-tal meteorological data in its basin to build relative function relation s among them,we probe quantitatively climatic sig-nals recorded in those indexes.The r esults show that there are remarkabl e relations betweenδ 13 C proxy and precipitation,δ 18 Oproxy and air temperature,of which correlative coefficient was 0.89an d 0.71,respectively.Besides,we also demon-strated that average variation betw eenδ 13 C proxy and precipitation(dδ 13 C /dP)was 0.027‰/mm and 1.64‰/℃forδ 18 O and air temperature(dδ 18 O /dT).展开更多
Background: The Food and Drug Administration recently announced that the use of morcellation may cause fibroids or pelvic dissemination and metastasis of uterine sarcoma; therefore, the use of morcellation is limited...Background: The Food and Drug Administration recently announced that the use of morcellation may cause fibroids or pelvic dissemination and metastasis of uterine sarcoma; therefore, the use of morcellation is limited in the USA. A large sample study is necessary to assess the proportion of uterine malignant tumors found in patients with laparoscopic myomectomy. Methods: A national multicenter study was performed in China. From 2002 to 2014, 33,723 cases were retrospectively selected. We calculated the prevalence and recorded the clinical characteristics of the patients with malignancy after morcellation application. A total of 62 cases were finally pathologically confirmed as malignant postoperatively. Additionally, the medical records of the 62 patients were analyzed in details. Results: The proportion of postoperative malignancy after morcellation application was 0.18% (62/33,723) for patients who underwent laparoscopic myomectomy. Nearly 62.9% (39/62) of patients had demonstrated blood flow signals in the uterine fibroids before surgery. And, 23 (37.1%) patients showed rapid growth at the final preoperative ultrasound. With respect to the pathological types, 38 (61.3%) patients had detectable endometrial stromal sarcoma, 13 (21.0%) had detectable uterine leiomyosarcoma, only 3 (3.2%) had detectable carcinosarcoma, and 5 (8.1%) patients with leiomyoma had an undetermined malignant potential. Conclusions: The proportion of malignancy is low after using moreellation in patients who undergo laparoscopie myomectomy. Patients with fast-growing uterine fibroids and abnormal ultrasonic tumor blood flow should be considered for malignant potential, and morcellation should be avoided.展开更多
Pollen records of two swamp sections, located at Taibai Mountain, the highest peak in the Qinling Mountains of central China, show variations of vegetation and climate for the last 3 500 cal BP. The pollen assemblage ...Pollen records of two swamp sections, located at Taibai Mountain, the highest peak in the Qinling Mountains of central China, show variations of vegetation and climate for the last 3 500 cal BP. The pollen assemblage at the Foyechi and Sanqingchi sections and the surface soil pollen allowed us to reconstruct a high-altitude vegetation history at Taibai Mountain for the first time. The data indicated that there was a cold-dry climate interval between 3 500 and 3 080 cal BP and a relatively warm and wet period compared with the present from 3 080 to 1 860 cal BE The warmest period in the late Holocene on Taibai Mountain was from 1 430 to 730 cal BP, with an approximate 2 ~C increase in mean annual temperature compared with today. There was a relatively cool-dry climate interval from 730 to 310 cal BE After 310 cal BE a mountain tundra vegetation developed again and the position of the modern tree line was established.展开更多
文摘Xingcuo lake,a closed one,is situated in eastern Tibetan Plateau.There are abundant snail shells Gy-raulus sibirica in its sediments.Here we display the determining results ofδ 13 C,δ 18 O in shell Gyraulus sibirica continuous-ly preserved in Xincuo Lake sediment s in the recent 50years.And by coupling the indexes ofδ 13 C,δ 18 O and instrumen-tal meteorological data in its basin to build relative function relation s among them,we probe quantitatively climatic sig-nals recorded in those indexes.The r esults show that there are remarkabl e relations betweenδ 13 C proxy and precipitation,δ 18 Oproxy and air temperature,of which correlative coefficient was 0.89an d 0.71,respectively.Besides,we also demon-strated that average variation betw eenδ 13 C proxy and precipitation(dδ 13 C /dP)was 0.027‰/mm and 1.64‰/℃forδ 18 O and air temperature(dδ 18 O /dT).
文摘Background: The Food and Drug Administration recently announced that the use of morcellation may cause fibroids or pelvic dissemination and metastasis of uterine sarcoma; therefore, the use of morcellation is limited in the USA. A large sample study is necessary to assess the proportion of uterine malignant tumors found in patients with laparoscopic myomectomy. Methods: A national multicenter study was performed in China. From 2002 to 2014, 33,723 cases were retrospectively selected. We calculated the prevalence and recorded the clinical characteristics of the patients with malignancy after morcellation application. A total of 62 cases were finally pathologically confirmed as malignant postoperatively. Additionally, the medical records of the 62 patients were analyzed in details. Results: The proportion of postoperative malignancy after morcellation application was 0.18% (62/33,723) for patients who underwent laparoscopic myomectomy. Nearly 62.9% (39/62) of patients had demonstrated blood flow signals in the uterine fibroids before surgery. And, 23 (37.1%) patients showed rapid growth at the final preoperative ultrasound. With respect to the pathological types, 38 (61.3%) patients had detectable endometrial stromal sarcoma, 13 (21.0%) had detectable uterine leiomyosarcoma, only 3 (3.2%) had detectable carcinosarcoma, and 5 (8.1%) patients with leiomyoma had an undetermined malignant potential. Conclusions: The proportion of malignancy is low after using moreellation in patients who undergo laparoscopie myomectomy. Patients with fast-growing uterine fibroids and abnormal ultrasonic tumor blood flow should be considered for malignant potential, and morcellation should be avoided.
基金国家重点基础研究发展计划(973计划),中国科学院资助项目,the Knowledge Innovation Program of the Chinese Academy of Sciences
文摘Pollen records of two swamp sections, located at Taibai Mountain, the highest peak in the Qinling Mountains of central China, show variations of vegetation and climate for the last 3 500 cal BP. The pollen assemblage at the Foyechi and Sanqingchi sections and the surface soil pollen allowed us to reconstruct a high-altitude vegetation history at Taibai Mountain for the first time. The data indicated that there was a cold-dry climate interval between 3 500 and 3 080 cal BP and a relatively warm and wet period compared with the present from 3 080 to 1 860 cal BE The warmest period in the late Holocene on Taibai Mountain was from 1 430 to 730 cal BP, with an approximate 2 ~C increase in mean annual temperature compared with today. There was a relatively cool-dry climate interval from 730 to 310 cal BE After 310 cal BE a mountain tundra vegetation developed again and the position of the modern tree line was established.