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71.
Simultaneous sonography and quantitative serum human chorionic gonadotropin (HCG) levels from 126 women with threatened abortion were compared. Of 56 women with normal outcome, 39 (70%) had a gestation sac greater than or equal to 5 mm in mean sac diameter, and in each case the HCG level was 1,800 milli-international units (mIU/ml) or greater. The serum HCG levels strongly correlated with the gestation sac sizes to a mean sac diameter of 25 mm. Of 70 abnormal pregnancies, 31 demonstrated a gestation sac. Of these, 20 women (65%) had disproportionately low HCG levels relative to sac size, including 12 in whom the HCG level was less than 1,800 mIU/ml. One woman with an early molar pregnancy had a disproportionately elevated HCG level. Correlation of sonograms with a simultaneous measurement of serum HCG level is a useful method for evaluating threatened spontaneous abortion. A disproportionately low HCG level relative to gestation sac size is evidence for an abnormal pregnancy. 相似文献
72.
Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms 总被引:1,自引:0,他引:1
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis. 相似文献
73.
Striking similarities in amino acid sequence among nonstructural proteins encoded by RNA viruses that have dissimilar genomic organization. 总被引:46,自引:7,他引:46 下载免费PDF全文
J Haseloff P Goelet D Zimmern P Ahlquist R Dasgupta P Kaesberg 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(14):4358-4362
The plant viruses alfalfa mosaic virus (AMV) and brome mosaic virus (BMV) each divide their genetic information among three RNAs while tobacco mosaic virus (TMV) contains a single genomic RNA. Amino acid sequence comparisons suggest that the single proteins encoded by AMV RNA 1 and BMV RNA 1 and by AMV RNA 2 and BMV RNA 2 are related to the NH2-terminal two-thirds and the COOH-terminal one-third, respectively, of the largest protein encoded by TMV. Separating these two domains in the TMV RNA sequence is an amber termination codon, whose partial suppression allows translation of the downstream domain. Many of the residues that the TMV read-through domain and the segmented plant viruses have in common are also conserved in a read-through domain found in the nonstructural polyprotein of the animal alphaviruses Sindbis and Middelburg. We suggest that, despite substantial differences in gene organization and expression, all of these viruses use related proteins for common functions in RNA replication. Reassortment of functional modules of coding and regulatory sequence from preexisting viral or cellular sources, perhaps via RNA recombination, may be an important mechanism in RNA virus evolution. 相似文献
74.
目的 探讨Lafora病的临床、病理特点及诊断方法.方法 总结分析5例经腋窝皮肤活体组织检查确诊的Lafora病患者的临床和组织病理学特点.5例患者都进行了腋窝皮肤活体组织检查,常规行HE、糖原(PAS)和阿辛蓝-糖原(AB-PAS)染色.结果 5例患者中4例青少年发病,1例成年起病.所有患者均表现为进行性加重的强直阵挛发作、肌阵挛和智能损害,可早期出现性格改变,构音障碍和行走不稳.腋窝皮肤活体组织检查发现Lafora包涵体存在于大、小汗腺的肌上皮细胞和导管细胞内.结论 经皮肤活体组织检查发现PAS阳性圆形或卵圆形包涵体,结合Lafora病典型的临床表现可以确诊该病;皮肤活体组织检查的部位可选择腋窝或腋窝以外的部位. 相似文献
75.
The kidneys in paroxysmal nocturnal hemoglobinuria 总被引:6,自引:0,他引:6
Long-term study of 21 PNH patients revealed an unexpectedly high incidence of functional and anatomic renal abnormalities. Most patients demonstrated varying degrees of hematuria and proteinuria distinct from hemoglobinuria. Evaluation of renal function revealed hyposthenuria, abnormal tubular function, and declining creatinine clearance. Radiologically these patients had enlarged kidneys, cortical infarcts, cortical thinning, and papillary necrosis which were confirmed by autopsy studies. Hypertension developed in eight patients. Urinary tract infection was uncommon. The renal findings bear striking similarity to those of sickle cell anemia. Contrary to the usual opinion, out studies clearly showed evidence of widespread renal pathology in PNH most likely due to repeated microvascular thrombosis similar to the venous thrombosis involving other organs in this disorder. 相似文献
76.
目的分析5例脊髓延髓肌萎缩症患者的临床特征,以便临床医生对该病的认识。方法收集基因确诊的5例脊髓延髓肌萎缩症患者的临床资料,分析其临床特点及血清性激素、各生化指标水平、脑脊液及肌电图特点。结果脊髓延髓肌萎缩症患者青年发病,病情进展缓慢。神经系统表现为以肢体近端和延髓部受累为主的瘫痪。舌肌受累较早,运动功能损害较轻。血清睾酮(969.3±234.9ng/dl)、雌二醇(57.1±5.3pg/ml)水平增高,男性乳腺发育出现在病史较长的患者。三核苷酸(CAG)重复序列数目43~51(平均47.2±3.6pg/ml)。患者的肌酸激酶(CK,481.8±264.8 IU/L)均增高,脑脊液检查均正常。肌电图为广泛神经源性损害。结论脊髓延髓肌萎缩症患者的早期症状不典型,易误诊,临床特征为青年起病,缓慢加重,以肢体近端无力为主的瘫痪。 相似文献
77.
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79.
AP Mishreki E Lim P Cranefield S Pascoe S Jackson DA Stell 《Annals of the Royal College of Surgeons of England》2013,95(5):349-352
Introduction
The results of surgical resection and palliative chemotherapy use in hilar cholangiocarcinoma (HC) have been well publicised but the proportion of patients able to undergo these treatments and the comparative outcomes in a population of patients with HC are less well known.Methods
Patients with HC were identified by review of all patients undergoing percutaneous cholangiography over a nine-year period (2002–2010) in a tertiary facility. The treatment undertaken and outcomes were recorded.Results
Overall, 68 patients were identified (37 female) with a median age of 70 years. Forty-five (66%) were treated solely by insertion of a metal stent (median survival 4.73 months) and nine (13%) also received palliative chemotherapy (median survival 13.7 months). Persisting jaundice after stent insertion was noted in 18 of 35 patients (51%) tested within one month of death. Fourteen patients (21%) underwent surgical resection (median survival 20.2 months).Conclusions
Patients undergoing surgical resection had significantly longer survival than those receiving only a palliative stent but not compared with those also receiving palliative chemotherapy, with short-term follow-up. Only a third of patients, however, receive active treatment (surgery or chemotherapy) and improvements in long-term biliary palliation are needed. 相似文献80.