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71.
Trisomy 6qter   总被引:2,自引:0,他引:2  
A previously reported patient with trisomy for the distal part of 6q was shown by R-banding to be trisomic for 6q26qter, due to a t(6;22)(q26;p12) mat. Altogether nine patients with 6qter trisomy have been reported. The main features of the 6qter trisomy syndrome are: severe mental and growth retardation; acrocephaly and brachycephaly; a carp-shaped mouth; micrognathia; a very short neck with unusual anterior webbing; joint contractures; the absence of severe inner organ malformations; and survival into adulthood.  相似文献   
72.
Partial trisomy 3q syndrome inherited from familial t(3;9)(q26.1; p23)   总被引:1,自引:0,他引:1  
A five-year-old girl was referred to prometaphase chromosome analysis because of mental retardation, facial dysmorphic features suggestive of Cornelia de Lange syndrome, cleft palate and additional minor congenital malformations of the cardiac system and fingers and toes. A familial balanced translocation (3;9)(q26.1; p23) was found. The karyotype of the proposita was 46,XX,der(9),t(3;9)(q26.1;p23). Thus the patient was trisomic for 3q26.1-qter and monosomic for 9p23-pter. The unbalanced chromosome constitution was not detected by standard Q-banding analysis shortly after birth. The karyotype was misdiagnosed as 46,XX,9(p+) in the proposita and her mother, and thought to be a normal variant of chromosome 9. The repeated cytogenetic study led to the diagnosis of the translocation and to the possibility of prenatal diagnosis in the translocation carriers. A survey of 22 published cases of dup(3q) showed that nearly 60% were secondary to familial balanced rearrangements with an excess of maternally derived abnormal chromosomes 3. Red blood cell galactose-1-phosphate-uridyltransferase (GALT) activity was normal in the patient, consistent with previous assignment of the gene locus for GALT to 9p13 (Shih et al. 1982).  相似文献   
73.
The long term success of total joint replacement can be limited by fatigue failure of the acrylic cement and the resulting disruption of the bone-cement interface. The incidence of such problems may be diminished by reduction of the fatigue notch factor in the cement, so that stress concentrations are avoided and the fatigue crack initiation time maximized. This study describes a method for numerical shape optimization whereby the finite element method is used to determine an optimal shape for the femoral stem of a hip prosthesis in order to minimize the fatigue notch factor in the cement layer and at interfaces with the bone and stem.

A two-dimensional model of the proximal end of a femur fitted with a total hip prosthesis was used which was equivalent to a simplified three-dimensional axisymmetric model. Software was developed to calculate the fatigue notch factor in the cement along the cement/stem and cement/bone interfaces and in the proximal bone. The fatigue notch factor in the cement at the cement/stem interface was then minimized using the ANSYS finite element program while constraining the fatigue notch factor at the cement/bone interface at or below its initial level and maintaining levels of stress in the proximal bone to prevent stress shielding. The results were compared with those from other optimization studies.  相似文献   

74.
目的:为桡侧腕短伸肌腱部分移位修复第一腕掌关节脱位提供解剖学依据。方法:30侧成人上肢标本,将桡侧腕短伸肌腱分为上、中、下3部分,进行形态学测量。结果:桡侧腕短伸肌腱长度为(15.3±1.9)cm(10~22.5cm),其宽度:上段为(15.4±5.2)mm(5.3~23.8mm),中段(10.0±3.0)mm(4.2~18.5mm),下段(5.5±0.6)mm(3.7~9.6mm);厚度:上段为(0.6±0.3)mm(0.1~1.4mm),中段为(1.8±0.7)mm(0.7~3.0mm),下段为(2.1±1.2)mm(0.8~3.1mm)。结论:桡侧腕短伸肌腱部分转位有足够的长度以修复第一腕掌关节脱位。  相似文献   
75.
Sixty-two placentas with a triploid DNA content, which were analyzed by flow cytometry using paraffin-embedded tissues, were histologically investigated. These placentas were histologically classified as follows: 51 partial hydatidiform moles (PM), two hydropic abortuses and nine non-hydropic placentas. The DNA indices of the triploid peaks were between 1.41 and 1.60. Histologically, two populations of normal and edematous villi, vesicular villous edema with cistern formation, focal syncytiotrophoblastic hyperplasia with vacuola-tion, and villous scalloping with trophoblastic inclusion were almost always observed in the PM, but no single pathologic feature was specific for PM. The two entities, PM and triploid placenta, overlapped. Not all triploid gestations are PM and not all PM moles are triploid as shown in previously reported diploid or tetraploid PM. Although no patient with triploid PM developed persistent disease in this series, follow up of triploid PM is required as long as its true biological potential remains unclear. Flow cytometry is a reliable aid in the diagnosis of PM.  相似文献   
76.
目的探讨不同类型心脏患者心内直视手术期间呼气末二氧化碳分压(PETCO2)与动脉血二氧化碳分压(PaCO2)的相关性及二者差值[P(a-ET)、CO2]的临床意义。方法45例患者分成3组,每组15例。A组:左向右分流组;B组:无分流组;C组:右向左分流组。3组分别于术前(T0)、插管后15min(T1)、手术开始时(T2)、转流前(T3)、转流停止后15min(T4)、术毕时(T5)共6个时点,用旁气流法监测PETCO2,同时抽动脉血测定PaCO2,应用直线回归分析3组各时点PETCO2与PaCO2的相关性,同时计算并分析各组不同时点的P(a-ET)CO2。结果(1)A组、B组各时点PETCO2与PaCO2呈正相关,A组r为0.70—0.85(P〈0.01),B组r为0.71—0.79(P〈0.01);C组麻醉开始至转停后PETCO2与PaCO2均无相关(0.46—0.54,P〉0.05),而到术毕时则呈正相关(r=0.66,P〈0.05)。(2)3组患者转流前的P(a-ET)CO2变化不大,停转流后A组、B组P[a-ET)CO2增加,其中以A组增加较明显(P〈0.01),而C组P(a-ET)CO2显著减少(P〈0.05)。结论无分流或左向右分流心脏患者在体外循环转流前后PETCO2与PaCO2的相关性较好;右向左分流心脏患者转流前的相关性较差,心内畸形纠正后其相关性可发生变化。P(a-ET)CO2在不同的心脏患者之间差异较大,必须与PaCO2相结合,才能正确指导临床。  相似文献   
77.
A recently reported device, the sorbent suspension reciprocating dialyser (SSRD), was investigated for use as a test system for biocompatibility of dialyser components. The device is easy to assemble and operate, and allows minimal blood contact with foreign material outside of dialyser components. Its constant pressure/ variable flow rate operation allows quantification of degree of clotting of dialyser versus time. The effect of heparinization of the blood distribution gaskets (BDG) of the device on performance and dialyser lifetime was investigated. Heparin was bound to the surface of polyethylene gaskets by immersion in a solution of tridodecylmethylammonium chloride (TDMAC)-heparin complex for several hours. Gaskets were then assembled in an SSRD which was then used for experimental dialysis in dogs with AV shunts. Dialysers assembled using non-heparinized gaskets were used as controls. Blood coagulation tendency was quantified by the activated clotting time (ACT) and partial thromboplastin time (PTT), and these values correlated with the rate of clotting of the device. Heparinization of the gaskets resulted in the prevention of clotting in the dialyser until the final minutes of dialysis in all cases, in contrast to the constant decay of blood fill volume and evidence of clotting in the non-heparinized cases. However, dialyser lifetime was not significantly increased by gasket heparinization. At normal initial values of ACT (80–95 s) dialyser clotting occurred in 10–15 mia In tests with non-heparinized gaskets and systemically heparinized dogs, values obtained in the ACT test were observed to decrease during dialysis, indicating the disappearance of heparin from the blood. Both ACT and PTT tests show promise as predictors of dialyser lifetime.  相似文献   
78.
We have studied 4 patients with inverted tandem duplications of parts of chromosomes, a hitherto rarely identified from of a structural rearrangement involving a single chromosome in man. In Patients 1 and 2, the duplication involved parts of the short arm of chromosome 8 (regions 8p 12→8p23 and 8p21→8p23, respectively). Both patients manifested certain characteristics of the mosaic trisomy 8 syndrome. Elevated levels of glutathione reductase (GSR) in their erythrocytes supported the interpretation of a partial duplication of chromosome 8 and indicated a regional localization for the GSR gene locus. In Patient 3, the distal half of the long arm of chromosome 4 was duplicated (region4q26→4q35). Clinical evidence supported this interpretation, as Patient 3 resembled phenotypically the 13 reported cases with duplication of the distal 4q. The cytogenetic findings in Patient 4 suggested a possibly inverted duplication of 22q. The clinical correlation was less convincing due to the lack of a well-defined phenotype for trisomy 22. These chromosome aberrations had occurred de novo in all 4 cases. Although they involved different chromosomal regions, they might well have arisen by the same mechanism. Possible modes of origin that are discussed in detail include unequal exchange between homologous chromosomes, between chromatids of 1 chromosome or between strands of 1 DNA duplex.  相似文献   
79.
A clinical and electroencephalographic study of 107 neurologically normal children with partial seizures was undertaken to verify the existence and determine the frequency of epileptic syndromes reported in selected populations. Sixty-three children had simple partial seizures, 39 had complex partial seizures, and 5 children were unclassifiable. The syndrome of benign partial epilepsy of children with rolandic spikes (BPEC, 38 cases) was clearly identified and its uniformly benign final prognosis was confirmed even if some of these children had at times severe or poorly controlled seizures. Among the children with simple partial seizures outside the BPEC (25 cases) and complex partial seizures (39 cases), no homogeneous clinical or electroclinical subgroup could be found. Two children with benign partial epilepsy and myoclonic-astatic seizures ("atypical benign partial epilepsy of childhood") and one child with "benign epilepsy with occipital spike-waves" were identified. 74% of children with epilepsy with complex partial seizures (ECP) had a 1-year seizure-free interval, and many children with epilepsy with simple partial seizures outside the BPEC group (ESP) had no more than two seizures. A benign course is thus not limited to the BPEC but is difficult to predict. Prospective studies are necessary to confirm the existence of well-defined benign syndromes among the idiopathic partial epilepsies of childhood, which appear quite rare outside the BPEC.  相似文献   
80.
阴茎癌56例临床分析   总被引:6,自引:0,他引:6  
目的 :探讨阴茎癌有效合理的治疗方法。方法 :总结分析 5 6例阴茎癌发病及治疗情况 ,其中鳞状细胞癌5 0例 ,乳头状瘤癌变 6例 ,行阴茎部分切除术 48例 ,阴茎全切并会阴部造口术 6例 ,双腹股沟淋巴清扫术 10例 ,包皮环切并血卟啉光敏治疗 2例。结果 :5 1例获得随访。行阴茎部分切除术者 5年和 10年生存率分别为83 3 %和 80 % ,行阴茎全切术者 5年生存率为 6 6 8%。结论 :包茎及包皮过长是导致阴茎癌的主要诱因。对于Ⅰ、Ⅱ期阴茎癌行阴茎部分切除术疗效确切  相似文献   
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