林床清理对落叶松(Larix gmelinii)人工林土壤呼吸和物理性质的影响

林下可再生生物质资源的利用是当今森林资源利用的热点,通过林床清理可以获得廉价可再生生物质资源,但其对林分土壤碳收支的影响尚不清楚。运用红外气体分析法（IRGA法）连续两年观测了林床清理对落叶松（Larix gmelinii）人工林土壤呼吸及物理性质的影响,并估算了林床清理生物质资源利用对落叶松人工林碳收支的影响。结果表明：林床清理能够降低落叶松人工林的土壤呼吸,2a的平均值由2．20μmol·m^-2s^-1降低到1．18μmol·m^-2s^-1,平均降低幅度1．02μmol·m^-2s^-1,年呼吸总量由41．2μmol·m^-2a^-1降至22．4μmol·m^-2a^-1,而且,使土壤呼吸Q10值从2．33降低到2．22,R0值从0．61μmol·m^-2s^-1降至0．36μmol·m^-2s^-1;林床清理能够使林床土壤温度冬季低于对照,而夏季则有相反趋势,清理使得林床土壤湿度变化幅度加大,而且秋季和春季较对照低,而夏季偏高;林床清理使得表层土壤容重要比对照未清理样地高53％（P〈0．05）,土壤非毛管孔隙度比未处理样地低49．5％（P〈0．001）,毛管孔隙度较对照未清理降低约15％（P〈0．001）。林床清理导致林下生物质资源所储藏的碳非呼吸性释放约175．0mol·m^-2,当考虑到林床清理导致的土壤呼吸的降低作用时,所测定的2a内土壤净碳支出由175．0mol·m^-2降低至137．4mol·m^-2。林床清理措施增加生物质资源利用和其所导致的土壤呼吸释放减少,能够减少非冉生资源利用导致的碳释放压力。但仍然需要注意到林床清理使得土壤物理结构发生改变,可能不利于落叶松的生长和落叶松林生态系统的稳定。     

经会阴三维超声评价不同分娩方式初产妇肛门括约肌复合体和盆膈裂孔的临床应用价值

摘要 目的：探讨经会阴三维超声在不同分娩方式初产妇肛门括约肌复合体（ASC）和盆膈裂孔（PH）影响的评估价值。方法：选择2017年1月～2019年12月我院进行分娩的初产妇150例,按照分娩方式分成阴道分娩组71例,剖宫产组79例,比较两组基线资料。对所有受试者均实施经会阴三维超声检查,比较两组缩肛动作下肛门内括约肌（IAS）远端、中端及远端平面厚度,肛门外括约肌（EAS）远端平面及耻骨直肠肌（PRM）中端平面厚度,分娩前、产后6周、产后3个月PH左右径、PH前后径以及PH面积。结果：两组孕妇年龄、孕周及体质指数比较无差异（P＞0.05）,阴道分娩组IAS近端6点钟方向、12点钟方向平面厚度以及IAS中端、12点钟方向平面厚度均小于剖宫产组（P＜0.05）。阴道分娩组EAS远端12点钟方向平面厚度小于剖宫产组（P＜0.05）。阴道分娩组产后6周的PH左右径大于剖宫产组（P＜0.05）。阴道分娩组产后6周的PH前后径大于剖宫产组（P＜0.05）。阴道分娩组产后6周的pH面积大于剖宫产组（P＜0.05）。结论：经会阴三维超声可有效评估初产妇ASC和PH的影响情况,分娩会对初产妇ASC和PH产生影响,阴道分娩的初产妇产后存在明显的ASC厚度减小和PH增大现象。     

Controls on the release of dissolved organic carbon and nitrogen from a deciduous forest floor investigated by manipulations of aboveground litter inputs and water flux

Although dissolved organic matter (DOM) released from the forest floor plays a crucial role in transporting carbon and major nutrients through the soil profile, its formation and responses to changing litter inputs are only partially understood. To gain insights into the controlling mechanisms of DOM release from the forest floor, we investigated responses of the concentrations and fluxes of dissolved organic carbon (DOC) and nitrogen (DON) in forest floor leachates to manipulations of throughfall (TF) flow and aboveground litter inputs (litter removal, litter addition, and glucose addition) at a hardwood stand in Bavaria, Germany. Over the two-year study period, litter manipulations resulted in significant changes in C and N stocks of the uppermost organic horizon (Oi). DOC and DON losses via forest floor leaching represented 8 and 11% of annual litterfall C and N inputs at the control, respectively. The exclusion of aboveground litter inputs caused a slight decrease in DOC release from the Oi horizon but no change in the overall leaching losses of DOC and DON in forest floor leachates. In contrast, the addition of litter or glucose increased the release of DOC and DON either from the Oi or from the lower horizons (Oe + Oa). Net releases of DOC from the Oe + Oa horizons over the entire manipulation period were not related to changes in microbial activity (measured as rates of basal and substrate-induced respiration) but to the original forest floor depths prior to manipulation, pointing to the flux control by the size of source pools rather than a straightforward relationship between microbial activity and DOM production. In response to doubled TF fluxes, net increases in DOM fluxes occurred in the lower forest floor, indicating the presence of substantial pools of potentially soluble organic matter in the Oe + Oa horizons. In contrast to the general assumption of DOM as a leaching product from recent litter, our results suggest that DOM in forest floor leachates is derived from both newly added litter and older organic horizons through complex interactions between microbial production and consumption and hydrologic transport.     

厦门市地面沉降影响分析与风险评价

城市的地面沉降一直以来都是沿海城市密切关注的问题。在沿海城市对高层建筑群诱发的地面沉降进行深入研究具有重要意义。获取地面沉降监测点的高程信息,分析了厦门市地面沉降情况与空间差异性。重点探讨建设用地、建筑容积率与土地利用转化信息这3种因素对厦门市地面沉降的影响,并对厦门岛地面沉降风险进行评估,可为厦门岛的高层建筑三维空间布局与优化研究提供先验知识。结果表明:(1)在2001—2015年厦门市整体的高程存在下降的趋势且较为缓慢,同时厦门市的城市建设规模不断变大且建设面积增速不断增大,与厦门市的城市地面的沉降发展趋势相同。(2)厦门市的高层建筑密度需达到一定程度才对地面沉降有影响,厦门岛的建筑容积率与地面沉降没有存在显著的相关性。(3)在不同土地利用转化建设用地对地面沉降的影响中:原水域用地沉降最为明显,建成时间越长,总沉降量越大;原耕地用地转化成高层建筑之后沉降有明显发生,也随着建成时间的延长有逐渐增加沉降量的态势;原园地、林地用地沉降只在少部分地区发生且与建成时间无明显差别。(4)厦门岛可用于城市建设区域中的53.34%是地面沉降中风险等级以上的。此外,本研究给出防御防治城市地面沉降风险的有效建议与措施。本研究结果可为厦门市城市化进程中的地面沉降监测、规划设计与决策等提供重要的数据支撑,为城市可持续发展提供科学的依据;也可为国内外其他城市的地面沉降监测分析和可持续发展研究提供理论依据和借鉴意义。     

三维超声技术对于评估压力性尿失禁女性患者盆底肌肉收缩及膀胱颈活动度的价值研究

摘要 目的：探讨三维超声技术对于评估压力性尿失禁（SUI）女性患者盆底肌肉收缩及膀胱颈活动度的价值。方法：选取2020年1月至2021年8月本院的收治的因产后SUI的女性患者60例作为观察组,另选择同期产后正常的女性受试者60例作为对照组,所有受试者均行经会阴三维超声检查。比较两组之间盆底肌肉收缩及膀胱颈活动度等相关指标的差异。结果：在静息状态和最大Valsalva状态下,观察组中盆膈裂孔前后径、左右径、肛提肌裂孔面积以及膀胱颈后角均显著大于对照组（P<0.05）,观察组尿道长度显著低于对照组（P<0.05）;而仅在最大Valsalva状态下,观察组的膀胱颈位置显著低于对照组（P<0.05）;此外观察组膀胱漏斗化所占比例显著高于对照组（P<0.05）。结论：三维超声技术可以清晰直观地显示女性盆底组织结构和功能,对于评估SUI女性患者盆底肌肉收缩及膀胱颈活动度具有一定的诊断价值,并为临床提供真实客观的影像学证据。     

前环经皮Infix固定联合后路固定治疗垂直不稳定骨盆骨折的效果

目的:探讨前环经皮内固定架(Infix)固定联合后路固定治疗垂直不稳定骨盆骨折的效果。方法:采用回顾性方法,选择本院2013年8月到2018年2月诊治的垂直不稳定骨盆骨折患者61例患者,根据手术方法的不同分为观察组31例与对照组30例,对照组给予钢板内固定治疗,观察组给予前环经皮Infix固定联合后路固定,记录与观察两组预后。结果:所有患者都完成手术,无术中严重并发症发生,观察组的切口长度、术中出血量与骨折愈合时间显著少于对照组(P0.05),两组手术时间与术中透视次数对比差异无统计学意义(P0.05)。观察组术后1个月的钉道感染、神经损伤、静脉血栓、切口感染发生率低于对照组(6.5%vs.33.3%, P0.05)。观察组与对照组术后3个月的Majeed评分优良率分别为93.5%和73.3%,骨折复位优良率分别为96.8%和73.3%,观察组高于对照组(P0.05)。结论:前环经皮Infix固定联合后路骶髂关节螺钉固定治疗垂直不稳定骨盆骨折能减少创伤,促进骨折愈合,减少术后并发症的发生,提高骨盆复位质量与骨盆功能。     

盆底肌肉康复训练联合盆底重建术对女性盆底功能障碍性疾病患者炎症反应及应激反应的影响

目的:观察盆底肌肉康复训练联合盆底重建术治疗女性盆底功能障碍性疾病(PFD)的疗效及对炎症反应及应激反应的影响。方法:选择2019年1月~2021年1月期间我院收治的PFD患者200例,按乱数表法分为对照组(100例)和研究组(100例)。对照组患者接受盆底重建术治疗,研究组患者接受盆底肌肉康复训练联合盆底重建术治疗。观察两组治疗后的疗效及术后并发症发生情况,对比两组相关量表评分、炎症反应及应激反应指标。结果:研究组治疗后盆底功能影响问卷简表(PFIQ-7)、盆底不适调查表简表(PFDI-20)评分低于对照组(P<0.05)。研究组治疗后盆底Ⅰ类肌纤维肌电压、盆底Ⅱ类肌纤维肌电压高于对照组(P<0.05)。研究组治疗后白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、超敏C反应蛋白(hs-CRP)低于对照组(P<0.05)。研究组治疗后皮质醇(COR)、去甲肾上腺素(NE)、前列腺素E2(PGE2)低于对照组(P<0.05)。研究组术后并发症发生率低于对照组(P<0.05)。结论:盆底肌肉康复训练联合盆底重建术治疗PFD,可促进盆底功能恢复,减轻机体炎症反应及应激反应,降低术后并发症发生率。     

Ontogeny and evolution of pelvic diameters in anthropoid primates and in Australopithecus afarensis (AL 288-1)

Pelvic diameters (both anteroposterior [AP] and transverse [TR]) were investigated in a series of anthropoid primates. The ratio of diameters (AP/TR) in each of three pelvic planes (inlet, midpelvis, and outlet) was calculated. In addition to the above, the length of the iliac, pubic, and ischial axes and the angles between these axes were determined. The AP/TR ratio at the pelvic inlet is (reported in millimeters, +/- SD, unless otherwise specified) 1.81 +/- 0.27 in New World monkeys (Cebidae) and Macaca mulatta; 1.53 +/- 0.17 in hylobatids and pongids; 0.87 +/- 0.08 in Homo sapiens; and 0.58 in Australopithecus afarensis (AL 288-1). The AP/TR ratio in the midpelvis is 1.61 +/- 0.23 in nonhominid primates (Cebidae, M. mulatta, hylobatids, and pongids), 1.12 +/- 0.11 in humans, and 0.59 in AL 288-1. In monkeys (Cebidae and M. mulatta), hylobatids, pongids, H. sapiens, and AL 288-1, the ratios of the length of the pubic axis over the ischial axis were 0.84 +/- 0.06, 0.95 +/- 0.07, 1.10 +/- 0.15, and 1.46, respectively; the pubis-ilium angles were 96 +/- 11, 120 +/- 10, 131 +/- 11, and 147 degrees, respectively; and the ischium-pubis angles were 106 +/- 11, 86 +/- 8, 96 +/- 7, and 68 degrees, respectively. In none of these pelvic features was AL 288-1 "intermediate" between pongids and H. sapiens. The anatomical peculiarities of the pelvis in AL 288-1 are explained primarily as the result of early adaptation to erect posture, which resulted in the reduction of the distance between the sacroiliac joint and the hip joint. As a consequence, the sacral promontory moved toward the pubic symphysis, and this resulted in shortening of the AP diameter and widening of the TR diameter at the pelvic inlet.     

Distribution and origin of neuropeptide Y-immunoreactive fibers in the penis of the rat

Summary The present study investigated the distribution of neuropeptide Y-immunoreactive fibers to the penis of the rat. In the corpora cavernosa penis, a dense plexus of fibers was asociated with arteries, intrinsic cavernosal muscle, and veins including the deep dorsal vein. In the corpus spongiosum, immunoreactive fibers were present around vascular smooth muscle and at the periphery of the acini of the paraurethral glands. Immunohistochemistry of penile neurons identified by retrograde tracer injection into the penis indicates that about 5% of the penile neurons in the pelvic plexus contained the neuropeptide while larger percentages of penile neurons in the sympathetic chains were immunoreactive for neuropeptide Y. Chemical and surgical sympathectomy greatly reduced the neuropeptide Y- and catecholamine-containing fibers in the erectile tissue but had no clear effect on the neuropeptide Y fibers around the paraurethral glands; a tissue that is not innervated by adrenergic fibers. It is concluded that (1) the widespread distribution of neuropeptide Y indicates that it may function in the control of penile blood flow, (2) with the possible exception of the paraurethral glands, the sympathetic chain is the most likely source of neuropeptide Y fibers in both erectile bodies of the penis, and (3) this peptide may play a role in the secretory functions of the paraurethral glands.     

Floor plate, glia and other support cells in the anterior nerve cord of amphioxus larvae

Serial electron micrograph reconstructions and interval series were used to examine the support cells, including glia, of the anterior nerve cord in 6-, 8- and 12.5-day larvae of Branchiostoma floridae and one newly metamorphosed juvenile. The floor plate begins immediately behind the infundibular cells. It consists for the most part of a single file of midline cells, but adjacent lateral floor plate cells occur in some places. The floor plate is interrupted at one point, in the posterior part of the cerebral vesicle above the tegmental neuropile. A class of early developing axons crosses the midline at this point, which suggests that the floor plate may have a developmental role in axon guidance. The structural integrity of the cord is maintained by ependymal and ependymoglial cells that attach to its sides. Two other glial cell types were found in larvae. Both appear to originate adjacent to the floor plate and hence are referred to here as midline glia. Those in somites 1 and 2 remain connected to the central canal; they appear to be a mixed population that may include precursors of midline support cells which are present later in the juvenile. Those caudal to somite 3 detach early from the central canal and develop an extensive network of axial processes; they are referred to here as axial glia and treated as a subcategory of midline glia. Based on their site of origin and the absence of glial filaments, their closest counterpart among vertebrate glia may well be the oligodendrocyte. To our knowledge, this is the first report of a possible amphioxus homologue of this important vertebrate cell type.