机械瓣替换术后抗凝与凝血状态的观察

为探讨心脏机械瓣膜替换术后口服华法令抗凝治疗期间,凝血因子的变化及μFPA与INR的相关关系,随机选取102例机械瓣替换术后口服华法令抗凝治疗患者,稳定抗凝治疗1个月以上.42例健康志愿者为对照组,一期法测定INR、纤维蛋白原(Fg)及凝血因子Ⅱ、x的活性ⅡC、xC;高效液相色谱法(HPLC)测定尿液纤维蛋白肽A的尿肌酐校正浓度(μFPA).结果表明口服华法令抗凝治疗者ⅡC、xC显著降低,分别为(48.5±20.2)%、(39.4±16.7)%;μFPA均值(6.7±4.3)ng/mgcr,显著低于正常值;INR在2.0～3.0时,ⅡC、xC适度抑制;INR>3.0时,呈过度抑制;INR在2.0～2.5时,μFPA与INR呈负相关(r=-0.5194,P<0.001);Fg在抗凝早期(3个月内)显著增高[(4.23+0.27)g/L,P<0.001],抗凝晚期(3个月以后)逐渐降至正常范围.小剂量口服华法令抗凝显著抑制ⅡC、xC,抗凝效果良好;国人抗凝适当范围INR2.0～3.0;μFPA小剂量抗凝时与INR呈负相关,与ⅡC、xC呈弱的正相关.用μFPA指导抗凝有一定价值.     

大鼠磨牙三维有限元模型的建立

目的 :建立大鼠磨牙的三维有限元模型 ,探讨牙及牙周组织的应力分布状况。方法 :采用Sprague Dawley大鼠 2 0只 ,建立大鼠磨牙正畸移动的动物模型 ,制作大鼠上颌第一磨牙牙周连续切片 ;采用计算机技术 ,重建牙及牙周组织三维形态、结构 ,并建立其三维有限元模型。结果 :组织切片的应力分布显示牙周膜是一种存在于两种硬组织之间的软组织 ,有其特有的应力分布状态。结论 :本研究建立的正畸大鼠磨牙三维有限元模型是观察正畸牙移动过程中分析应力的一种简便、准确、可靠的模型及方法。     

The Functional Status of the ACL in Varus OA of the Knee: The Association With Varus Deformity and Coronal Tibiofemoral Subluxation

BackgroundThe present article analyzes the association of the functional anterior cruciate ligament (ACL) status and the overall varus deformity and coronal tibiofemoral subluxation (CTFS) in varus OA of the knee.MethodsOne hundred consecutive knees with varus OA in 84 patients were prospectively included. Knees were divided into two groups, in accordance with the ACL status (functionally sufficient or insufficient). All included patients were potential candidates for unicompartmental knee arthroplasty with predominantly medial compartment OA. Knees with Kellgren/Lawrence ≥ grade 3 in the lateral compartment were excluded leaving 79 knees to be included in this study. Mechanical varus deformity and CTFS were evaluated on AP radiographs and valgus stress radiographs, and compared between the two groups.ResultsKnees with a functionally insufficient ACL had significantly more varus deformity on hip-to-ankle AP standing radiographs (P = .001) and on valgus stress radiographs (P = .017). CTFS on AP standing radiographs was significantly higher (P = .045) in knees with a functionally insufficient ACL. Seventy-three percent (8/11) of the ACL-insufficient knees had a varus deformity of ≥10° and 64% (7/11) of ACL-insufficient knees had CTFS ≥ 6mm. By contrast, only one patient (2%, 1/41) with an insufficient ACL had< 10° varus deformity and a CTFS of < 6mm.ConclusionFunctional ACL insufficiency in osteoarthritic varus knees is associated with greater varus deformity and more advanced CTFS. Seventy-three percent of ACL-insufficient knees had a varus deformity of ≥10° and 64% of ACL-insufficient knees a CTFS of ≥ 6mm. In the work-up for medial unicompartmental knee arthroplasty, functional ACL insufficiency is likely in knees with varus deformity of ≥10° and CTFS of ≥ 6mm.     

Alignment in Medial Fixed-Bearing Unicompartmental Knee Arthroplasty: The Limb Has a Leg Up on the Component

BackgroundTo assess how implant alignment affects unicompartmental knee arthroplasty (UKA) outcome, we compared tibial component alignment of well-functioning UKAs against 2 groups of failed UKAs, revised for progression of lateral compartment arthritis (“Progression”) and aseptic loosening (“Loosening”).MethodsWe identified 37 revisions for Progression and 61 revisions for Loosening from our prospective institutional database of 3351 medial fixed-bearing UKAs performed since 2000. Revision cohorts were matched on age, gender, body mass index, and postoperative range of motion with “Successful” unrevised UKAs with minimum 10-year follow-up and Knee Society Score ≥70. Tibial component coronal (TCA) and sagittal (TSA) plane alignment was measured on postoperative radiographs. Limb alignment was quantified by hip-knee-ankle (HKA) angle on long-leg radiographs. In addition to directly comparing groups, a multivariate logistic regression examined how limb and component alignments were associated with UKA revision.ResultsIn the Progression group, component alignment was similar to the matched successes (TCA 3.6° ± 3.5° varus vs 5.1° ± 3.5° varus, P = .07; TSA 8.4° ± 4.4° vs 8.8° ± 3.6°, P = .67), whereas HKA angle was significantly more valgus (0.3° ± 3.6° valgus vs 4.4° ± 2.6° varus, P < .001). Loosening group component alignment was also similar to the matched successes (TCA 6.1° ± 3.7° varus vs 5.9° ± 3.1° varus, P = .72; TSA 8.4° ± 4.6° vs 8.1° ± 3.9°, P = .68), and HKA was significantly more varus (6.1° ± 3.1° varus vs 4.0° ± 2.7° varus, P < .001). Using a multivariate logistic regression, HKA angle was the most significant factor associated with revision (P < .001).ConclusionIn this population of revised UKAs and long-term successes, limb alignment was a more important determinant of outcome than tibial component alignment.Level of EvidenceLevel III case-control study.     

右美托咪定与丙泊酚对外科术后机械通气患者镇静效果及血流动力学的影响

目的 探究右美托咪定与丙泊酚对外科术后机械通气患者镇静效果及血流动力学的影响。方法 将我院60例外科手术后机械通气患者作为研究对象,电脑随机将其分成右美托咪定组和丙泊酚组,各30例。右美托咪定组给予右美托咪定治疗,丙泊酚组给予丙泊酚治疗,比较两种方法的镇静效果及对血流动力学的影响。结果 镇静30 min后,两组的Ramsay镇静评分对比差异无统计学意义(Z=1.23,P>0.05);右美托咪定组心动过缓(6.67%)、低血压(13.33%)、低血压合并心动过缓(3.33%)发生率分别低于丙泊酚组(30.00%、36.67%、26.67%),两组间对比差异有统计学意义(χ2分别为5.45、4.36、6.41,P均<0.05)。结论 给予外科术后机械通气患者右美托咪定或丙泊酚,均有更好的镇静效果,但右美托咪定对于血流动力学的影响较小,更适用于机械通气患者。     

Gabapentin (neurontin) and S-(+)-3-isobutylgaba represent a novel class of selective antihyperalgesic agents

1. Gabapentin (neurontin) is a novel antiepileptic agent that binds to the α₂δ subunit of voltage-dependent calcium channels. The only other compound known to possess affinity for this recognition site is the (S)-(+)-enantiomer of 3-isobutylgaba. However, the corresponding (R)-(−)-enantiomer is 10 fold weaker. The present study evaluates the activity of gabapentin and the two enantiomers of 3-isobutylgaba in formalin and carrageenan-induced inflammatory pain models.
2. In the rat formalin test, S-(+)-3-isobutylgaba (1–100 mg kg⁻¹) and gabapentin (10–300 mg kg⁻¹) dose-dependently inhibited the late phase of the nociceptive response with respective minimum effective doses (MED) of 10 and 30 mg kg⁻¹, s.c. This antihyperalgesic action of gabapentin was insensitive to naloxone (0.1–10.0 mg kg⁻¹, s.c.). In contrast, the R-(−)-enantiomer of 3-isobutylgaba (1–100 mg kg⁻¹) produced a modest inhibition of the late phase at the highest dose of 100 mg kg⁻¹. However, none of the compounds showed any effect during the early phase of the response.
3. The s.c. administration of either S-(+)-3-isobutylgaba (1–30 mg kg⁻¹) or gabapentin (10–100 mg kg⁻¹), after the development of peak carrageenan-induced thermal hyperalgesia, dose-dependently antagonized the maintenance of this response with MED of 3 and 30 mg kg⁻¹, respectively. Similar administration of the two compounds also blocked maintenance of carrageenan-induced mechanical hyperalgesia with MED of 3 and 10 mg kg⁻¹, respectively. In contrast, R-(−)-3-isobutylgaba failed to show any effect in the two hyperalgesia models.
4. The intrathecal administration of gabapentin dose-dependently (1–100 μg/animal) blocked carrageenan-induced mechanical hyperalgesia. In contrast, administration of similar doses of gabapentin into the inflamed paw was ineffective at blocking this response.
5. Unlike morphine, the repeated administration of gabapentin (100 mg kg⁻¹ at start and culminating to 400 mg kg⁻¹) over 6 days did not lead to the induction of tolerance to its antihyperalgesic action in the formalin test. Furthermore, the morphine tolerance did not cross generalize to gabapentin. The s.c. administration of gabapentin (10–300 mg kg⁻¹), R-(−) (3–100 mg kg⁻¹) or S-(+)-3-isobutylgaba (3–100 mg kg⁻¹) failed to inhibit gastrointestinal motility, as measured by the charcoal meal test in the rat. Moreover, the three compounds (1–100 mg kg⁻¹, s.c.) did not generalize to the morphine discriminative stimulus. Gabapentin (30–300 mg kg⁻¹) and S-(+)-isobutylgaba (1–100 mg kg⁻¹) showed sedative/ataxic properties only at the highest dose tested in the rota-rod apparatus.
6. Gabapentin (30–300 mg kg⁻¹, s.c.) failed to show an antinociceptive action in transient pain models. It is concluded that gabapentin represents a novel class of antihyperalgesic agents.

     

不同通气方式对机械通气引起急性肺损伤兔模型的影响

目的：通过表面活性物质缺乏的兔肺模型,评估传统通气模式（ｃｏｎｖｅｎｔｉｏｎａｌ ｍｅｃｈａｎｉｃａｌ ｖｅｎｔｉｌａｔｉｏｎ,ＣＭＶ）与允许性高碳酸血症加最佳ＰＥＥＰ（ｐｅｒｍｉｓｓｉｖｅ ｈｙｐｅｒｃａｐｎｉａａｓｓｏｃｉａｔｅｄ ｗｉｔｈｉｄｅａｌＰＥＥＰｖｅｎｔｉｌａｔｉｏｎ,ＰＨＹ＋ ＰＥＥＰｉ）的通气模式对肺损伤的影响,了解肿瘤坏死因子α（ｔｕｍｏｒ ｎｅｃｒｏｓｉｓｆａｃｔｏｒα,ＴＮＦα） 与机械通气引起肺损伤（ｖｅｎｔｉｌａｔｏｒｉｎｄｕｃｅｄｌｕｎｇｉｎｊｕｒｙ,ＶＩＬＩ） 的关系。方法：１２ 只成年兔,以反复肺灌洗法制备表面活性物质缺乏兔肺模型。以ＣＭＶ（Ｃ组） 或ＰＨＹ＋ ＰＥＥＰｉ （Ｐ 组） 通气４ ｈ 后,测定通气前、后的支气管肺泡灌洗液（ｂｒｏｎｃｈｏａｌｖｅｏｌａｒ ｌａｖａｇｅ ｆｌｕｉｄ,ＢＡＬＦ）中ＴＮＦα含量和白细胞分类计数,测定肺水量,进行动脉血气分析和病理检查。结果：ＣＭＶ 组表现为明显的低氧血症,ＢＡＬＦ中较多的中性粒细胞数,总肺水量及血管外肺水量明显增多,肺内病理改变为较明显透明膜形成及炎性细胞聚集;而ＰＨＹ＋ ＰＥＥＰｉ 组引起较少的上述病理、生理变化。且ＣＭＶ 组ＢＡＬ     

动态硫化PP／EPDM强化增韧机理的动态力学研究

采用动态力学试验方法,研究了不同ＥＰＤＭ含量的动态硫化和简单共混两种ＰＰ／ＥＰＤＭ材料动态力学响应的差异及其特征。结果显示：与简单共混ＰＰ／ＥＰＤＭ相比,动态硫化ＰＰ／ＥＰＤＭ具有ΔＴｇ小,内耗峰扩宽程度大,低温和室温内耗峰强度高,所处温度低,６０－７０℃时内耗峰强度发生高低变位,在ＥＰＤＭ相的α转变以下还显示β和γ次级转变等特性。     

高晶体-高胶体渗透压溶液对受机械性损伤的海马神经细胞容积的影响

观察机械性损伤的海马神经细胞在不同浓度高晶体－ 高胶体渗透压溶液中容积的变化。取原代培养大白鼠胚胎的海马神经细胞,用超声波机械损伤细胞后暴露于含０．５ ｇ／Ｌ、１ ｇ／Ｌ和２．５ ｇ／Ｌ氯化钠的细胞培养基中１５ ｍ ｉｎ。结果显示机械性损伤的细胞明显肿胀（Ｐ＜ ０．０５）。当细胞暴露于不同浓度的高晶体－ 高胶体溶液１５ ｍ ｉｎ 后, 细胞容积与同一实验时间的对照值相比明显下降, 并保持至第７ ｄ （Ｐ＜ ０．０５）。表明受到机械性损伤的海马神经细胞在高晶体－ 高胶体渗透压环境中的容积调节功能丧失或减弱。     

慢性阻塞性肺疾病继发急性呼吸衰竭机械通气治疗10例分析

目的：探讨慢性阻塞性肺疾病（ＣＯＰＤ）所致急性呼吸衰竭行机械通气（ＭＶ）治疗的转归及其影响因素。方法：通过对１０例ＣＯＰＤ所致急性呼吸衰竭患者的资料分析,评价ＭＶ治疗的临床疗效。结果：９例２￣４２天内撤机并拔管存活。结论：适宜的ＭＶ参数调节,良好的呼吸道管理,预防感染和营养支持对尽早撤机非常重要,其预后较好。