| 1 | Vegetation and soil carbon storage in China显示文摘This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors. | LI Kerang, WANG Shaoqiang & CAO MingkuiInstitute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Department of Geography, Maryland University, College Park,MD 20742, USA Correspondence should be addressed to Li Kerang | 2004 | Science China Earth Sciences2004,47,1: | 60 |
| 2 | Angioplasty with Stent for Symptomatic Intracranial Stenosis Trial I (ASSIT-Ⅰ) Study显示文摘Background and Purpose Annual stroke rates might be as high as 10% to 24% in patients with symptomatic intracranial stenosis on best medical therapy. Angioplasty with stent for symptomatic intracranial stenosis trial Ⅰ (ASSIST-Ⅰ) was a prospective and nonrandomized feasibility and safety study to evaluate the APOLLO Stent System for treatment of symptomatic intracranial artery stenosis, and prepare for ASSIST Ⅱ-a prospective, multicenter,and randomized controlled-study. The APOLLO stent delivery system (MicroPort Medical [Shanghai] Limited Co.), specifically designed for intracranial artery stenosis, consists of a stent and a balloon and a rapid-exchange delivery catheter. The stent is made of 316L stainless steel, with diameters of 2.0 to 4.0 mm and length of 8 mm or 13 mm. Only two links connect the rings of 1 mm in length, rendering the stent a good flexibility enough to navigate tortuous intracranial vessels. The nominated pressure of the stent is designed at 6 atm to reduce the risk of occlusion to side branches and perforators and rupture and dissection of target vessel. The crimping technique is applied in this system, insuring a compact ability of stent so wonderful that the struts of stent do not lift when the stent negotiates a turn, which lessen the likelihood of vessel wall injury and stent migrating. Materials and methods Thirty-four patients with 35 symptomatic intracranial stenoses of ≥50%, which resulted in transient ischemic attacks (TIAs [23 lesions /22 patients]) and minor stroke (7 lesions/7 patents), and both TIAs and stroke (5 lesions/ 5 patients), and with 1 asymptomatic severe stenosis, were enrolled in ASSIST-Ⅰ from December 10, 2003 to August 12, 2004. Their age was 54.3 years±SD of 9.49, three patients were male, and all had ≥1 risk factors of atherosclerosis. Patients received the evaluation of National Institutes of Health Stroke Scale (NIHSS), modified Rankin scale (mRS )and Barthel idex (BI) before and one-, three-, six-, and 12-month after the procedure. Results Stent success, defined as stent-assisted angioplasty successfully, resulting in ≤20% residual stenosis, was obtained in 35 lesions ( 97.2%, 35/36) and 33 patients ( 97.1%, 33/34). The stenosis rate of pre- and post -procedure was 80.5%± SD of 12.65 and 7.4%±SD 15.74, respectively. The Procedure-related complications were 8.3% for lesion (3/36) and 8.8% for patient (3/34), included 1 acute thrombosis, which obtained complete patency by means of intrathrombus thombolysis at once without sequelae, and 2 ischemic perforator strokes (1 irreversible stroke and 1 reversible). The disable stroke, defined as one that led to mRS score of ≥2, 30 days after the stroke, occurred in one patient ( 2.9%, 1/34; mRS of 2). Procedure success, defined as stent success without disable stroke or death at discharge by means of the endovascular therapy, was achieved in 33 lesions ( 91.7%, 33/36) and in 31 patients ( 91.2%, 31/34). Treatment success, defined as stent success without disable stroke and death at the 30th day, by means of the endovascular and medical therapy, was obtained in 34 lesions ( 94.4%, 34/36) and 32 patients ( 94.1%, 32/34). Clinical Follow-up, median 170 days (ranged from 30 days to 273 days; ≥1 month, n=34; ≥3 months, n=23; ≥6 months, n=13), was performed in 34 patients. There were no ischemic neurological events and death occurred. Cumulated disable stroke occurred in 1 patient ( 2.9%, 1/34). NIHSS was 1.09±SD of 1.694 and 0.47±SD of 1.051, before procedure and at the 30th day (n=34), respectively, and 0.57±SD of 0.992 at 3 months (n=23), 0.15±SD of 0.376 at 6 months (n=13), respectively; mRS was 0.65±SD of 0.812 and 0.47±SD of 0.563, before procedure and at 30 days, respectively, and 0.61±SD of 0.583 at 3 months, 0.38±SD of 0.506 at 6 months, respectively; and BI was 97.54±SD of 5.918 and 99.26±SD of 2.179, before procedure and at 30 days, respectively, and 99.35±SD of 2.288 at 3 months, 100.00±SD | Wei-Jian Jiang, MD Min Jin, MD Bin Du, MD Yong-Jun Wang, MD Xiao-Tong Xu, MD Qing-He Wang, MD Ning Ma, MD Long-Yi Wang, MO Jian-Ping Dai, MD From the Neurovascular Angioplasty Team, Department of Neurology and Neuroradiology, Beijing Tiantan Hospital, Capital University of Medical Sciences, Beijing, China. Correspondence to Wei-Jian Jiang, MD, Department of Neurology and Neuroradiology, Beijing Tiantan Hospital, Capital University of Medical Sciences, Beijing, 100050, China. | 2004 | 介入放射学杂志2004,13,S1: | 2 |