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991.
Juergen Thiele Hans Michael Kvasnicka Robert Fischer Volker Diehl 《Leukemia & lymphoma》1997,24(5):463-481
In this report an attempt has been made to discuss some of the issues pertinent to myelofibrosis complicating chronic myeloproliferative disorders (CMPDs) that are significantly associated with megakaryocyte function. In this context, biochemical, clinical and particularly morphological features were reviewed. Morphological findings based on elaborate techniques were in keeping with the assumption that in chronic myeloid leukemia (1) the number of CD61-positive megakaryocytes, and in particular their precursors were the parameters most closely associated with myelofibrosis (2) an increased content of reticulin fibers in follow-up biopsies significantly correlated with laboratory data indicative of a high tumor burden (anemia, peripheral blasts, hepatosplenomegaly) and thus a more advanced stage of the disease process (3) even a slight increase in reticulin, i.e. doubling of the normal fiber density was associated with a worse prognosis independent of therapeutic regimens given (4) Dynamics of myelofibrosis was significantly influenced by treatment. In this context, calculation of the myelofibrosis progression index (MPI) revealed a higher score following interferon therapy compared with busulfan. In addition, in idiopathic myelofibrosis (5) the evolution of myelofibrosis was unpredictable and according to the MPI, progression occurred at a relatively low rate (6) proliferation and dilatation of sinusoids accompanying intravascular hematopoiesis and collagen type IV deposits were predominant features in later (fibro-osteosclerotic) stages in the course of disease (7) transmural migration of megakaryocytes demonstrated by three dimensional reconstruction revealed a mole-like tunneling through the thickened sinusoidal wall. A very careful assessment of the numerous correlations between bone marrow features and laboratory data will allow clinicians and pathologists to gain a better insight into the mutual relationships between hematological and morphological findings in CMPDs. 相似文献
992.
抗HBc阳性,HBsAg阴性献血者乙型肝炎病毒感染性研究 总被引:12,自引:0,他引:12
目的为预防输血后乙型肝炎,是否有必要在献血者中加做抗-HBc筛查以及采取何种取舍标准?为此,对常规筛查合格的献血者血液进行了抗-HBc滴度与HBVDNA相关性的研究。方法用免疫-套式PCR法检测了297份不同滴度组抗-HBc阳性血液的HBVDNA。结果在4份抗-HBc滴度≥1128的血液中检出1例HBVDNA,而在另75份抗-HBc滴度<1128的血液中未检出,HBVDNA与抗-HBc滴度之间有显著相关性。在218份抗-HBc/抗-HBs双阳血液及50份抗-HBc阴性血液中未检出HBVDNA。结论仅含高滴度单项抗-HBc的血液可能具有传染性;HBVDNA在抗-HBc阳性血液中的总检出率低,仅为0.34%(1/297)。建议将有限的资金首先用于进一步提高现有献血者HBsAg检测试剂的灵敏度(目前为1ng/ml),或许更为有效。 相似文献
993.
目的:评价多普勒血流显象技术检测卵巢肿瘤内血流定性诊断卵巢肿瘤的价值。方法:对疑诊卵巢肿瘤的75例(其中53例卵巢良性肿瘤和22例恶性肿瘤)于术前1w内行C超检查及肿瘤内血流检测,并与术后组织病理学诊断对照。结果:53例卵巢良性肿瘤中的21例(39.62%)及22例卵巢恶性肿瘤中的21例(95.45%)C超均显示其结构鼻常;在21例卵巢良性肿瘤内检测到血流高峰收缩速度(PSV)的均值为14.2±8.1cm/s,阻抗指数(RI)均值为0.478±0.119。当以PSV=16cm/s为卵巢良、恶性肿瘤的界值时,PSV诊断卵巢恶性肿瘤的敏感性和特异性率分别为90.91%和90.57%;当以RI=0.72为卵巢良、恶性肿瘤的界值时,RI诊断卵巢恶性肿瘤的敏感性和特异性率分别为86.36%和69.81%;C超诊断卵巢恶性肿瘤的敏感性和特异性率分别为95.45%和71.70%。三者的敏感性差异无显著性,而PSV诊断卵巢恶性肿瘤的特异性率明显高于RI和C超检查者,差异具有显著性(P<0.05)。结论:用多普勒血流显象技术检测卵巢肿瘤内异常。流的PSV,对预测卵巢肿瘤性质具有一定的临床意义。 相似文献
994.
目的:研究妊高征(PIHS)患者胎盘合体滋养细胞质膜(STCPM)中生化指标的变化及原因。方法:PIHS24例,其中轻度8例、中度7例、重度9例,以正常孕妇18例作对照,用Whitset等法制备STCPM,以孔雀石绿无机磷法(MGIoPA)测定ATPase的活性,用DPH荧光探针测定膜的微粘度来推断膜的流动性,用硫代巴比妥酸荧光微量测定法测丙二醛酸(MDA)以代表脂质过氧化物(LPO)。结果:PIHS组Na+、K+-ATPase、Ca2+、Mg2+-ATPase活性均显著低于对照组(P<0.05),且随病情加重而降低,膜的流动性亦显著降低(P<0.05),MDA则显著增高,且随病情加重而增高;MDA与两种ATP酸呈负相关关系(P<0.05)。结论:PIHS的STCPM生化指标发生变化,其变化的原因之一是脂质过氧化作用增强 相似文献
995.
Hisayuki Hiraiwa Minoru Hamazaki Satoru Tsuruta Hiroyoshi Hattori Jun-Ichi Mimaya Shirou Hasegawa Sumio Kohno Katsuhiko Aoki 《Pediatrics international》1998,40(6):604-607
Infantile hemangioendothelioma of the thymus is a rare disease. We describe a patient who developed a large anterior mediastinal mass, severe thrombocytopenia and massive pleural effusion at 1 month of age. Glucocorticosteroid and irradiation therapy had no effect on either the tumor size or clinical symptoms and the tumor was resected subtotally. Three months after the subtotal resection, the remaining tumor had almost disappeared and the symptoms had resolved. The patient has now been well for 1 year after surgery without evidence of recurrence. The tumor tissue was characterized by prominent vascular endothelial proliferation intermixed with a normal thymic structure, producing a picture consistent with that of an infantile hemangioendothelioma in the thymus, lmmunohistochemically, the tumor cells showed positive staining for vimentin, factor VIII and CD34. The DNA stemline and proliferative activity were examined by flow cytometry, which revealed a diploid stemline with a low growth fraction. DNA content and cell cycle analyses of the tumor tissue may be useful for predicting the biological behavior of the tumor. 相似文献
996.
M. Collinet M. Berthelon P. Bénit K. Laborde B. Desbuquois A. Munnich J. J. Robert 《European journal of pediatrics》1998,157(6):456-460
Familial hyperproinsulinaemia is a rare genetic disorder characterized by point mutations in the insulin gene which impair
the conversion of proinsulin to insulin. We report here three members of a two-generation Caucasian family in whom this syndrome
was identified by unexplained hyperinsulinism associated with normal glucose tolerance and normal insulin sensitivity. Plasma
insulin immunoreactivity showed a reduced affinity for the insulin receptor and eluted mainly, on Biogel chromatography, at
the position of proinsulin. Analysis of the PCR-amplified insulin gene by restriction enzyme mapping revealed a new recognition
site for the enzyme Nla III, indicating a Arg65 to His mutation. Sequence analysis of exon 3 confirmed this mutation in one allele of the gene.
Conclusion This study reports a two-generation European-Caucasian family with hyperproinsulinaemia due to a substitution of His for
Arg at position 65 in proinsulin, the seventh now identified worldwide and the second from Europe. The mutation generated
a new restriction site on the insulin gene suggesting the usefulness of restriction enzyme mapping as a screening procedure.
Received: 27 June 1997 / Accepted in revised form: 28 November 1997 相似文献
997.
目的应用分子生物学技术建立人类颞骨火棉胶切片中的DNA分析方法。方法采用多聚酶链反应(polymerasechainreaction,PCR)配合不同的引物、扩增方式及酶切技术检测长期保存的7例(9侧)颞骨火棉胶切片中微量线粒体DNA的片段缺失及点突变,pGEMT载体进行扩增片段的重组与克隆。结果9侧颞骨DNA提取液中均可见正常的135bp扩增片段,巢式PCR检出其中2例生前患老年聋者(各查1侧)有线粒体DNA大片段缺失,测序结果证实扩增的准确性。结论分子生物学技术在颞骨切片研究中的应用对于提高其回顾性研究水平有重要意义,目前可在耳科疾病的研究中发现相关的基因突变或病原体。 相似文献
998.
Objectives: To verify the validity of the recently described sciatic functional index for mice to monitor neuronal functional recovery over time using a blinded, randomized, and controlled evaluation. Study Design: Surgery was performed on the left sciatic nerves of 62 C57/BL mice after randomly assigning them to one of four surgical groups: sham surgery, sciatic nerve crush, nerve transection without repair, and nerve transection followed by epineurial suture repair. Sciatic functional indices were measured before surgery and then after surgery at 10-day intervals for 90 days, using a previously described formula. Results: Sham surgery did not affect nerve function when compared with preoperative values (P > .24). Crush surgery produced a reversible nerve injury that fully recovered after 20 days. Nerve transection without repair resulted in complete functional disability without recovery of function during the 90-day follow-up interval. When transected nerves were repaired, complete functional disability was noted at day 10, with subsequent functional recovery to 26% of function at day 30. This level of recovery persisted until the 60th postoperative day when muscle contractures resulted in progressive worsening of the index. There were statistically significant differences between the sciatic functional indices of each of the groups (P < .05). Conclusions: The previously described sciatic functional index for mice is an accurate indicator of the level of sciatic neuronal function during recovery. This index represents a method of evaluating neuronal function that may provide a better reflection of the recovery parameters that are important in clinical situations. The sciatic functional index will allow for study of sciatic nerve functional recovery in genetically engineered transgenic mice. 相似文献
999.
Hala U Gali-Muhtasib Makhluf J Haddadin Musa Z Nazer Nicole M Sodir Samar W Maalouf 《Medical oncology (Northwood, London, England)》1998,15(4):262-269
2-benzoyl-3-phenylquinoxaline 1,4-dioxide (BPQ) and other substituted quinoxaline 1,4-dioxides (QdO) were tested for their
ability to inhibit the stimulations of ornithine decarboxylase (ODC) enzyme activity and DNA synthesis, two biochemical markers
linked to skin tumour promotion by ultraviolet B (UVB) radiation. Topical application of BPQ on the dorsal skin of hairless
mice was found to inhibit in a dose-dependent manner UVB-induced ODC activity and DNA synthesis. When applied 20 min before
UVB radiation, a dose of 17 mg BPQ applied in 0.4 ml of vehicle inhibited UVB-induced ODC activity and DNA synthesis by 95%
and 85%, respectively. This inhibitory effect is dependent on the time of administration of BPQ relative to UVB radiation,
with a generally greater inhibition observed when this compound is applied before rather than after UVB treatment. The inhibitory
abilities of the other QdO on the ODC and DNA responses induced by UVB radiation greatly varied and appear to be dependent
on the structure of the compounds and their metabolic activation in the skin following irradiation. The remarkable effectiveness
of BPQ against the ODC and DNA markers of UVB promotion is also observed following multiple applications of this agent. These
results suggest that QdO, in particular BPQ and certain derivatives of it, may be useful in protecting the skin against UVB-induced
skin damage. 相似文献
1000.