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991.
Catechol-O-methyltransferase is a candidate in the predisposition to schizophrenia both because of its function and the position of its gene. A multipoint non-parametric linkage analysis and a transmission disequilibrium test were performed on 42 multiplex families genotyped for Pml I and Bcl I polymorphisms using two definitions of the affected phenotype. Neither linkage nor preferential transmission of any allele or haplotype was detected, failing to replicate previous positive findings.  相似文献   
992.
PURPOSE: Renal impairment, which is frequently observed in elderly patients, raises the question of low molecular weight heparins treatment dose adjustment in this population. Thus, we conducted a prospective study to determine whether tinzaparin, administered subcutaneously at treatment dose (175 anti-Xa IU/kg) once daily for 10 days, does accumulate in patients older than 70 years of age. METHODS: Accumulation criteria were an increase of plasma anti-Xa and anti-IIa levels determined prior to the first injection and on days 2, 5, 7 and 10. The characteristics of the 30 consecutive included patients receiving tinzaparin at treatment dose (six men, 24 women) were: age 87.0 +/- 5.9 years (range: 71-96 years), body weight: 62.7 +/- 14.6 kg (range: 38-90 kg) and creatinine clearance 40.6 +/- 15.3 mL/min (range: 20-72 mL/min). RESULTS: None of the patients required a dose adjustment of tinzaparin over the 10-day treatment period. Anti-Xa and anti-IIa activity levels on day 2 were 0.66 +/- 0.20 IU/mL (range: 0.26-1.04 IU/mL) and 0.33 +/- 0.10 IU/mL (range: 0.18-0.55 IU/mL), respectively. These levels did not significantly change over the 10 days. These results favor the absence of the accumulation effect of tinzaparin. There was no correlation between anti-Xa and anti-IIa activities and age, weight, or creatinine clearance. Concerning the side-effects, only one minor hematoma at the injection site was reported. CONCLUSION: Tinzaparin may thus be administered in older patients with renal impairment, at a treatment dose (175 anti-Xa IU/kg/d) for a 10-day treatment period, without accumulation effect nor hemorrhagic side-effect in patients with creatinine clearance greater than 20 mL/min.  相似文献   
993.
994.
Recurrent cytomegalovirus infection during pregnancy is considered less dangerous for the fetus than primary infection. We present a case of severe fetal cytomegalic inclusion disease after maternal reactivation of cytomegalovirus during the first trimester of pregnancy. The possibility of such fetal injury is an argument for prenatal diagnosis in seropositive pregnant women when ultrasonographic findings suggest cytomegalovirus infection.  相似文献   
995.
Corticobasal degeneration is a neurodegenerative disease characterized, by cortical dysfunction and extrapyramidal signs. The most consistent symptom is a unilateral limb apraxia, which consists of an isolated disorder of gestural production involving primarily the upper limb. The objective of this study is to investigate the functional abnormalities that may underlie motor dysfunction, and those which might correlate to the severity of limb apraxia.  相似文献   
996.
RATIONALE AND OBJECTIVES: The suitability of paramagnetic complexes as magnetic resonance contrast agents depends on various factors such as their relaxivity, stability, selectivity, and the inertness toward transmetallation by endogenous ions. The transmetallation of a series of 18 gadolinium complexes by the Zn2+ ion was studied in vitro by proton relaxometry. METHODS: Transmetallation was analyzed through the evolution of the paramagnetic longitudinal relaxation rate of water protons at 37 degrees C in pH = 7 phosphate buffer solutions containing 2.5 mmol/L of the gadolinium complexes and 2.5 mmol/L zinc chloride. The measurements were performed at 0.47 T over a period of at least 3 days. RESULTS: The results confirm the high stability of macrocyclic systems and a high sensitivity of Gd-diethylenetriamine-pentaacetic acid (DTPA) derivatives to transmetallation by Zn2+ ions. The decreasing order of stability with respect to metal exchange is as follows: Gd-macrocyclics > Gd-C-functionalized DTPA > Gd-DTPA > primary and secondary Gd-DTPA bisamides. The ternary bisamide analyzed in this study [Gd-DTPA-1,11-bisbismethylamino-1,11-dioxo-3,6,9-triaza-3,6,9-tris(carboxymethyl)undecane] is more stable than the parent compound Gd-DTPA. CONCLUSIONS: A simple relaxometric protocol has been successfully developed to study the in vitro transmetallation process of gadolinium complexes. The importance of the functionalization and substitution of the DTPA-like complexes is clearly shown.  相似文献   
997.
As a rule, the occlusal plane in man is not flat but curved in the three dimensions. This curved organization is related to a specific phenomena: the continuity of the dental arch without diastema. The Page's proposal of the tangent law explains the sagittal organization of the mandibular teeth by geometrical analyses. A cephalometric analysis of 485 subjects, in natural dentition, is the basis for the present statistical study of the mandibular teeth sagittal inclination, related to the direction of the tangent. Mandibular incisors follow the tangent law, but the long axis of the posterior mandibular teeth exhibits a postero-anterior and progressive differential angle with the direction of the tangent: 15 degrees, 20 degrees, 25 degrees, 28 degrees. The differential angle with the direction of vertical strength during closure movement generates an horizontal strength component, with a tendency to create a forward tooth movement. This horizontal component of force is tightening the proximal contacts, maintaining the continuity of the dental arch: it also originates the mesial "drift" and mandibular incisor crowding.  相似文献   
998.
目的采用心肌内注射方法将骨髓间充质干细胞(BMSCs)植入到正常或慢性梗死心肌中后, 研究短期内植入细胞的分布和可利用度。方法采用选择性冠状动脉结扎方法建立大鼠慢性心肌梗死模型( n =9) 。1个月后, 采用心肌内注射方法将 111 铟 - 羟基喹啉 ( 111Indium- oxine, 111In) 同位素标记的自体 BMSCs (2×106/50μL)植入到慢性梗死心肌和正常对照心肌中( n =6) 。采用序列平面针孔闪烁扫描方法测定 BMSCs移植后 2 h、1 d、3 d、7 d 时的心肌 111In 的放射活性, 并计算植入细胞在心肌内的驻留率。于细胞移植术后第 7 天切取制备心脏横断面冷冻切片, 进行组织放射微成像(Micro- imaging)和组织病理学分析, 观察植入细胞在心肌内的分布情况。结果慢性心肌梗死(MI)组的心肌 111In 的放射活性在所有测定的时间点均显著高于正常对照组(P<0.01)。心肌放射强度实测值在经由各相应时间点 BMSCs细胞 111In 的自发泄漏率的体外标定值校正后, 计算得出植入的 BMSCs 细胞在慢性梗死心肌(MI 组)中的驻留率平均为 60%, 而在正常对照组心肌中细胞的驻留率只有 25%(P <0.01), 并在 7 d 的随访期中保持稳定。组织放射微成像和组织病理学分析都证实植入的 BMSCs 主要分布于由注射针头插入损伤或慢性心肌梗死所造成的纤维瘢痕组织中。结论心肌内细胞移植术后 7 d 内,被植入到慢性梗死心肌中的 BMSCs 细胞的可利用度高于被植入在正常心肌中的 BMSCs 细胞的可利用度。植入心肌内的 BMSCs 主要分布于由注射针头插入损伤和慢性心肌梗死导致的纤维瘢痕组织中。  相似文献   
999.
In the absence of specific chromosomal translocations the best method for detecting minimal residual disease (MRD) in B cell malignancies is based on the uniqueness of immunoglobulin (Ig) genes rearrangement. We here report a very sensitive method for assessing MRD in complete hematological remission (CHR) chronic lymphocytic leukemia (CLL) patients as defined by the international workshop on CLL (IWCLL). Patients: Twelve CLL patients in CHR and complete phenotypic remission (CPR) were included in the study. Eight of them received Fludarabine (FDR), one was treated by Chop regimen, and the remaining 3 were rescued by polychemotherapy followed by autologous bone marrow transplantation (ABMT). Methods: DNA extracted from peripheral blood lymphocytes (PBL) of each patient was amplified with VH family specific and framework 3 primers in 5 and a consensus JH primer in 3, before treatment and sequentially after the CPR completion. When no clonal rearrangement could be detected by this assay, the CDR3 sequence specific probe of the clone was used as the 3 primer, associated to the VH family specific primer in 5. PCR products were analyzed by classical procedures in agarose and/or acrylamide gels. Results: Mixtures of leukemic cells and normal PBL showed detection of a single leukemic cell among more than 105 normal cells. Four out of the 12 patients achieved molecular remission (MR) when employing CDR3 amplifification. All 3 autografted patients were in MR, whereas only one out of the 9 patients treated by chemotherapy alone achieved MR. When using a clone specific probe, a clonal signal was observed in all cases but one (ABMT). Results presented here confirm that MR may be achieved in a few cases of B-CLL. Further studies are needed to determine the exact relationship between MRD and clinical outcome.This work was supported by a grant from Schering S.A.  相似文献   
1000.
A 42-year-old woman, who had undergone excision of a melanoma of her right forearm 3 years before (Breslow's index 4.4 mm), was admitted to hospital for the evaluation of an superior vena cava syndrome. The thoracic CT scan and the phlebography showed obstruction of the superior vena cava by an endovascular tumor. Abdominal, pelvis and cranial CT scans did not reveal any other metastatic localization. Surgery with extracorporeal circulation was performed. The mass was resected and histopathologic examination confirmed the endovascular metastatic melanoma. There was no heart metastasis. The patient was then given a polychemotherapy. She was still alive after 18 months of follow-up after the initial metastasis. To our knowledge, no similar case has previously been reported and surgical treatment, as for isolated heart metastatic melanoma, may be considered for vascular metastasis, as in our case.  相似文献   
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