胎兔骨髓基质前成骨细胞的培养及鉴定

为了证实体外培养的胎兔骨髓基质骨祖细胞具有成骨细胞系特征。采用胎兔长管骨骨髓细胞 ,加入 DMEM培养 ,传代四代后 ,用活体相差显微镜、透射电镜、组织化学染色、免疫组化等方法进行观测。结果显示体外培养的基质细胞具有成骨细胞系特征。提示胎兔骨髓基质骨祖细胞 ,可以作为修复骨缺损的种子细胞。     

脐血造血干细胞移植对肿瘤化疗病人骨髓功能的影响

1目的　探讨脐血造血干细胞移植对因化疗所致骨髓功能抑制的恶性肿瘤病人骨髓造血功能重建的临床意义。 2方法　从健康人脐血中纯化制备造血干细胞 ,每例病人每天静脉输注 2× 10 9个造血干细胞 ,连续5 d.以治疗前后自身对照进行疗效评价。 3结果　治疗前白细胞计数为 (2 .78± 1.72 )× 10 9/ L,治疗后第 7天为(4.5 5± 1.0 1)× 10 9/ L,两组比较有显著性差异 (F=18.5 0 ,q=6 .95 ,P<0 .0 1) ;治疗前血红蛋白含量为 (12 1.5 6±11.2 7) g/ L,治疗后第 14天为 (130 .72± 12 .5 8) g/ L,治疗前后比较差异有极显著意义 (F=14.0 2 ,q=4.90 ,P<0 .0 1) ,且治疗后第 2 1天比治疗后第 7天增高 (F=14.0 2 ,q=6 .2 6 ,P<0 .0 1) ;治疗前血小板计数为 (192 .38±18.2 1)× 10 9/ L,治疗后第 2 1天为 (2 0 1.5 7± 17.86 )× 10 9/ L,治疗前后比较差异有极显著意义 (F=9.0 1,q=3.99,P<0 .0 1)。 4结论　脐血造血干细胞移植对于重建或改善骨髓造血功能有一定疗效。提升白细胞速度较血红蛋白及血小板为快。     

脐血造血细胞培养的特性

目的　培养脐血中具有造血潜能的造血细胞 ,分析脐血中造血细胞的特性。方法　用密封的采血袋采集脐血 ,采用羟乙基淀粉一次沉淀法分离有核细胞 ,用半固体培养体系培养 ,7天计数红系集落形成单位 (CFU E) ,14天后计数红系爆式集落形成单位 (BFU E)、粒单系集落形成单位 (CFU GM) ,同时染色分析集落的组成成分。结果　采集 34份脐血 ,平均体积为 (99± 2 2 )ml;有核细胞数为 (0 6 4～ 2 5 9)×10 9,有核细胞回收率为 79 2 %± 13 7% ,回收的有核细胞绝对值为 (1 2 2± 0 43)× 10 9;平均每份脐血中含有BFU E(1 39± 0 75 )× 10 6,CFU GM (2 15± 1 2 2 )× 10 6。结论　脐血富含各期具有造血潜能细胞 ,每份脐血在有核细胞数和各种集落总数都可以满足成人移植的需求。     

胎心监护与过期妊娠的关系

目的：探讨胎心监护（ＦＨＲＭ）在过期妊娠中判断胎儿情况的可靠性。方法：８６例过期妊娠孕妇人院时做ＦＨＲＭ,共做１８１例次。评定以末次ＦＨＲＭ为准,于产后７天对新生儿出生时Ａｐｇａｒ评分,地羊水量及性状、胎盘级别与形态、脐带情况和新生儿预后进行随访,并与末次ＦＨＲＭ结果相对照。结果：８６例ＦＨＲＭ欠正常图型５５便,异常图型３１例。围产儿死亡４例。ＦＨＲＭ与围产儿死亡率对照诊断符合率９８．３７％。结论     

临产时初产妇胎头浮动对分娩的影响

目的 了解临产时初产妇胎头浮动发生因素及对分娩的影响,探讨产时如何采取合理措施,有利分娩。方法 采用回顾性资料分析方法,对１９９９年１月至２０００年４月在我院分娩的临产时初产妇胎头浮动孕妇１５０例的临床资料进行分析。并与随机抽样同期分娩单胎头位初产妇临产时胎头入盆１７０例孕妇进行比较。结果 临产时初产妇胎头浮动的原因除可知因素外,另有许多病例未查出明显原因。其手术产率较入盆组明显升高。结论 临产时     

脐血临床应用前的实验研究

对５８例脐血红细胞进行了计数和血红蛋白含量测定,并测定乙肝两对半、丙肝抗体、人类免疫缺陷病毒抗体、肝功能及Ｔ细胞亚群分类和细菌培养。结果表明无传染病的正常孕妇分娩时的脐血,可作血源供临床使用并能用于治疗多种原因引起的贫血。     

A comparison of perinatal mortality between ethnic Chinese and ethnic whites: Why the Chinese rate was lower

Objectives. To confirm the observation that has been occasionally reported in the literature that perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and to assess the reasons for this lower perinatal mortality rate.

Methods. Secondary‐analysis based on published data.

Results. This exercise demonstrates that the perinatal mortality rate was lower in ethnic Chinese than in ethnic whites. The birth weight distribution in ethnic Chinese was more favourable with reduced births at two extremes of the distribution, and the exposure to risk factors for perinatal death by their mothers was also lower.

Conclusion: Perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and the lower perinatal mortality rate in ethnic Chinese is probably caused by their favourable birth weight distribution and lower exposure to risk factors of perinatal death by their mothers.     

肾性骨病的骨膜下骨吸收

笔者采用手骨直接Ｘ线放大摄影和双手Ｘ线平片来研究慢性肾衰血透病人５１例。特征性的指骨骨膜下吸收放大摄影发现２５例占４９％;平片为１１例占２１．６％,结果表明,放大摄影的阳性率明显高于平片（Ｐ＜０．００５）,骨膜下吸收的二,三指中间指骨桡侧及指骨末端是肾性骨病的“靶区”,认为二者无显著差异（Ｐ＞０．５０）。骨膜下吸收还与血透时间,血磷,血钙和碱性磷酸酶水平相关。     

Ontogeny of serine hydroxymethyltransferase isoenzymes in fetal sheep liver, kidney, and placenta

Serine is an amino acid that is not transported from the placenta to the ovine fetus. Thus, fetal plasma serine levels may be controlled by flux through their relevant biosynthetic pathways. This study was designed to determine, in fetal sheep tissues, the ontogeny of the three key enzymes in the biosynthetic pathway for serine, the cytosolic (c) and mitochondrial (m) isoforms of serine hydroxymethyltransferase (SHMT), phosphoglycerate dehydrogenase (PGD), and phosphoserine aminotransferase (PSAT). PGD and PSAT activity did not vary during gestation in either liver (PSAT, 9.4 +/- 1.3 nmol/min/mg cytosolic protein; and PGD, 76 +/- 10 mU/mg protein) or placenta (PGD, 8.0 +/- 3.6 mU/mg protein). In the liver, cSHMT activity was low early in gestation (0.6 +/- 0.5 nmol/min/mg protein at 45 days), rose in the last one-third of gestation, and peaked in the newborn period (25 +/- 3 nmol/min/mg protein at 1 week of age). Hepatic cSHMT RNA levels parallel the activity pattern. Mitochondrial SHMT was stable throughout gestation and with low constant mSHMT RNA levels. In contrast, the kidney and placenta had high mSHMT and steady low cSHMT activity throughout gestation. These data support the possible role of SHMT in the fetal control of plasma serine levels. While cSHMT may contribute to fetal hepatic serine production, its activity pattern does not support a primary role in the control of fetal hepatic serine biosynthesis. In the placenta, mSHMT may be important for glycine production from serine.     

Extracellular signal-regulated kinase (ERK) activation by the pre-T cell receptor in developing thymocytes in vivo

The first checkpoint in T cell development occurs between the CD4(-)CD8(-) and CD4(+)CD8(+) stages and is associated with formation of the pre-T cell receptor (TCR). The signaling mechanisms that drive this progression remain largely unknown. Here, we show that extracellular signal-regulated kinases (ERKs)-1/2 are activated upon engagement of the pre-TCR. Using a novel experimental system, we demonstrate that expression of the pre-TCR by developing thymocytes induces ERK-1/2 activation within the thymus. In addition, the activation of this pre-TCR signaling cascade is mediated through Lck. These findings directly link pre-TCR complex formation with specific downstream signaling components in vivo.