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101.
The role of del (11)(p13) as a cause of aniridia, with and without Wilms tumor, is strengthened by demonstration of this chromosome aberration in 3 patients: monozygous twin girls, both of whom have aniridia and mental retardation and one of whom has a Wilms tumor; and an unrelated boy with aniridia and ambiguous genitalia. The break points defining the interstitial deletion for the twins are 11p13 and 11p15.1, while for the boy they are 11p1302 and 11p14.1. These patients and their karyotypes substantiate the critical importance of chromosome band 11p13 (or its hemizygous representation) in the development of aniridia and an associated Wilms tumor diathesis, as had been suggested previously (Riccardi VM, Sujansky E, Smith AC, Francke U, (1978): Pediatrics 61, 604-610).  相似文献   
102.
The calcium ionophore A23187(A23) at concentrations exceeding 1 microgram/ml has been shown to be progressively cytotoxic for human blood basophils, neutrophils, lymphocytes, and erythrocytes. Toxicity to basophils was considered to be manifested by the increasing inability of 2-deoxyglucose (2DG) to inhibit histamine release (HR) at increasing concentrations of A23. The toxicity to neutrophils and lymphocytes was demonstrated by decreased lactate production (LP) after incubation with A23 of Ficoll-Hypaque fractions greatly enriched in each respective cell type. Red cells present in dextran-sedimented leukocytes were increasingly susceptible to lysis during washing subsequent to exposure to increasing concentrations of A23. A concentration of 4 microgram A23/ml, which is cytotoxic at 37 degrees C, produced optimal and noncytotoxic HR at 22 degrees C. It was possible to reduce A23 concentrations required for optimal HR by increasing Ca++ from 0.6 to 3 mM.  相似文献   
103.
Several recent reports have described cases of acute nonlymphocytic leukemia with a unique chromosome translocation, t(6;9)(p23;q34). We have studied three additional patients who have acute nonlymphocytic leukemia and t(6;9)(p23;q34). Our findings provide additional support for the suggestion that this translocation is yet another distinct cytogenetic abnormality associated with myeloproliferative disorders.  相似文献   
104.
We encountered a 38-year-old Japanese male patient with chronic myelogenous leukemia (CML), whose bone marrow and peripheral blood cells during the chronic and blastic phases contained a complex Ph1 translocation and an extra Y chromosome [i.e., 47,XYY,t(9;22;13)(q34;q11;q14)]. A karyotypic analysis of PHA-stimulated lymphocytes showed the constitutional karyotype to be 47,XYY. Thus, it was considered that CML with a complex Ph1 translocation developed in an XYY male; such a case has not been reported, so far. A B-lymphocyte cell line with the complex Ph1 translocation was established by the procedure of Epstein-Barr virus transformation. The presence of the complex Ph1 translocation in the B-lymphocyte cell line suggests that some of the B lymphocytes in this patient originated from the CML clone.  相似文献   
105.
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107.
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   
108.
We have studied 46 Hymenoptera-allergic patients and 11 nonallergic controls by grading the severity of their sting reaction, determining their skin test reactivity, and performing human leukocyte histamine release with a commercial mixed stinging insect extract. A significant correlation was found between increasing severity of sting reaction and increasing skin test reactivity (p < 0.001). In 4146 allergic patients from 15 to 100 per cent release of total cellular histamine occurred, whereas in the 11 nonallergic controls no greater than 10 per cent release of total cellular histamine was observed. Skin test reactivity correlated significantly with cell sensitivity in the allergic patients (p < 0.001). Following hyposensitization therapy, cell sensitivity generally did not change, but significant increases in antigen-neutralizing capacity (A.N.C.) of allergic serum did occur in 1115 Hymenoptera-allergic patients.  相似文献   
109.
DRw6 has been difficult to define serologically. In the present experiments we have developed T cell lines in order to characterize the components of a DRw6 haplotype. This was accomplished by priming T cells with allogeneic mononuclear cells mismatched for DRw6, Dw6, and MT2. Subsequently, three sublines with distinct reactivity patterns were derived by limiting dilution. The specificities detected by these sublines included: (a) a specificity found on a subset of cells positive for DRw6 which was inhibited by monoclonal antibodies against DS(DC), the human homologue of the murine IA-encoded molecules, (b) another DRw6-associated specificity blocked by an MT2-like antibody, and (c) an MT2-like specificity blocked by monoclonal antibodies reactive with a different MT2-associated determinant. These results show that more than one IE-like, as well as the DS/DC (IA-like) molecules, carry distinctive antigenic epitopes that can be recognized by allogeneic T cells. Primed T cell lines may be useful for a better definition of certain haplotypes which are at present difficult to characterize with serological reagents alone.  相似文献   
110.
Based on the experience reported herein, the following conclusions have been made: (1) Although nonoperative means, including sclerotherapy, have an important role in the management of bleeding varices, they are not definitive means of treating recurrent variceal hemorrhage. (2) Because of the maintenance of hepatopetal flow and splanchnic venous hypertension, a selective shunt is associated with a lower incidence of encephalopathy and provides a better quality of life than does a nonselective shunt. Thus, an elective distal splenorenal shunt is the elective operation of choice for recurrent variceal hemorrhage. (3) Nonselective shunts can be performed with similar expectation of patient survival as selective shunts, but because of increased encephalopathy, should be reserved for emergency operations, in cases of unsuitable venous anatomy, and in those patients with intractable ascites. (4) A well-conceived elective shunt procedure can be performed with low operative mortality and long-term patency, results in significant survival, and is still considered the "gold standard" for treatment of variceal bleeding.  相似文献   
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