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41.
42.
Two sisters with hereditary prolidase deficiency are presented. Recurrent and painful leg ulcers are the predominant feature.  相似文献   
43.
The ability of macrophages to stimulate immune responses is heterogeneous and may have influence on the type of the developing immune response. Therefore, in an attempt to define different functional states of mouse macrophages, we made use of the two macrophage growth factors: macrophage colony stimulating factor (M-CSF) and granulocyte macrophage colony stimulating factor (GM-CSF). Generation of macrophages from freshly isolated bone marrow cells in the presence of GM-CSF results in a population expressing profound antigen presenting function for mouse TH1 cells, resulting in strong lymphokine production and proliferation of the T cells. Furthermore, high amounts of a novel soluble cytokine active on mouse TH1 cells are generated during the interaction of TH1 cells with macrophages elicited with GM-CSF. In contrast, macrophages grown from bone marrow cells for at least 14 days in the presence of M-CSF express only minimal antigen-presenting function for TH1 cells. Treatment of such macrophages for 24 h with either IFN-gamma or GM-CSF allows the distinction between two further functional states. Those treated with IFN-gamma efficiently presented antigen towards TH1 cells. The T cells produced large amounts of lymphokines and proliferate well. However, synthesis of the novel soluble cytokine (active on TH1 cells) was not detectable. The generation of this mediator requires a short-term treatment with GM-CSF of macrophages developed in the presence of M-CSF prior to their interaction with TH1 cells.  相似文献   
44.
The first prospective investigation of thyroid weights of over 20 years old adults in the GDR is presented. The material is based on autopsy findings from the Brandenburg area before using salt with iodine. Judging by the results this area appears as an endemiological one. Relationships to iodine content of drinking water, comparisons with autopsy statistics of other countries, and the role of regional epidemiological differences are pointed out. The importance of the investigation for patients care and the possibility of controlling the effect of using salt with iodine is underlined. The examination of relations between thyroid weight and anthropometric data showed no additional results.  相似文献   
45.
46.
Using criteria from the Centers for Disease Control, anemia and iron-deficiency anemia (anemia with serum ferritin concentrations less than 12 micrograms/L) were assessed in greater than 800 inner-city gravidas at entry to prenatal care. Iron-deficiency anemia was associated with significantly lower energy and iron intakes early in pregnancy and a lower mean corpuscular volume. The odds of low birth weight were tripled and of preterm delivery more than doubled with iron deficiency, but were not increased with anemia from other causes. When vaginal bleeding at or before entry to care accompanied anemia, the odds of a preterm delivery were increased fivefold for iron-deficiency anemia and doubled for other anemias. Inadequate pregnancy weight gain was more prevalent among those with iron-deficiency anemia and in those with anemias of other etiologies. The prevalence of iron-deficiency anemia (3.5%), however, was lower than anticipated for an inner-city, minority population in whom most anemias had been attributed clinically to iron deficiency.  相似文献   
47.
Cell mediated immunity (CMI) was assessed by the ImmuKnow assay in 12 patients after kidney transplantation, who presented with viral infection. Treatment included lowering of immunosuppression in all cases and antiviral treatment if indicated. The assay was repeated during the follow up. The ImmuKnow assay at time of presentation of viral infections was 56.8 ± 58.2 (range 3–178; median 22) ATP ng/ml. With the clearance of viral infection and lowering of immunosuppression, the assay showed an increase in the level of CMI at 194.5 ± 118.9 (range 53–409; median 150) ATP ng/ml. There was viral clearance or stabilization in all cases and there was no incidence of allograft rejection. The ImmuKnow assay of CMI can be used to titrate initial immunosuppression reduction and its subsequent increase, in patients with viral infection after transplantation.  相似文献   
48.
Hepatitis B virus (HBV) DNA is detectable in a number of liver transplant candidates who are negative for hepatitis B surface antigen (HBsAg). After liver transplantation (LT), such patients may have molecular and/or serologic evidence of HBV replication. However, clinical disease from reactivation of occult HBV infection after LT has not been described. We report a patient who underwent LT for cryptogenic cirrhosis and had to be retransplanted twice for hepatic artery thrombosis. The patient was negative for HBsAg and positive for anti-hepatitis B core (HBc) and anti-HBs before all LT procedures and developed acute hepatitis B shortly after receiving the third graft. The HBV strain isolated at that time exhibited an unusual in frame insertion of a CAG motif within the HBV polymerase (HBV(INS+)). HBV(INS+) was detected retrospectively as a minor species in pretransplantation sera and the explanted native liver by insertion-specific polymerase chain reaction. This case in an occult HBV carrier shows that clinically apparent, endogenous reinfection of the graft may occur with minor HBV variants that are not detectable in pretransplantation samples by standard diagnostic procedures. This has implications for the analysis of sources of acute hepatitis B in patients after LT and possibly for consideration of antiviral prophylaxis in anti-HBc/anti-HBs/HBV DNA-positive patients.  相似文献   
49.
In contrast to other types of congenital heart defects, the treatment of hypoplastic left heart syndrome (HLHS) has become comparably successful only within the last decade. Postnatal management of circulatory disturbances of HLHS was previously often performed, similarly to other types of neonatal shock, without considering the peculiarities of postnatal hemodynamics. It is of overwhelming importance to limit pulmonary hyperperfusion by reducing systemic afterload and avoiding artificial respiration. The invention of selective hypothermic cerebral perfusion using the modified Blalock-Taussig shunt has decreased the need for long circulatory arrest times involving the brain, and promises a better neurological outcome. Postoperatively, sophisticated hemodynamic monitoring is mandatory to provide sufficient systemic oxygen delivery. α-blockers are usually given for strong afterload reduction. Hospital mortality is as low as 10–15% in centers experienced with the Norwood operation. The next surgical steps to create a serial systemic and pulmonary circulation involve superior cavopulmonary anastomosis performed as early as possible (4–6 months) and finally total cavopulmonary connection at an age of 3–4 years.  相似文献   
50.
We found that naive (CD45RA+) CD4 T cells have a lower capacity of adhesion to Epstein-Barr virus (EBV) immortalized B cells than memory (CD45RO+) CD4 T cells, as judged by conjugate formation. This would appear to be due to differences in the expression of adhesion molecules [lymphocyte function-associated antigen (LFA)-1, CD2]. However, kinetic studies showed that the degree of adhesion of naive T cells to B cells was stable over 60 min while that of memory T cells, like that of unseparated CD4 T cells, was characterized by a rapid formation and rapid dissociation of conjugates. This could be explained by a difference in the sensitivity of naive and memory CD4 T cells to down-regulation of antigen-independent adhesion by CD4-MHC class II interaction. Indeed, memory T cells also adhered stably to MHC class II(-) B cells. The adhesion of memory T cells, but not naive T cells, to MHC class II(+) B cells was sensitive to inhibition by OKT4a an anti-CD4 antibody, human immunodeficiency (HIV) gp160 (env) protein and a 12-mer peptide encompassing the 35-46 sequence of the HLA, DR beta 1 domain and previously shown to inhibit activation of HLA class II-restricted CD4 T cell responses. Since MHC class II expression did not influence the degree of conjugate formation by naive or memory CD4 T cells with B cells, CD4-MHC class II interaction does not appear to be involved in binding itself, but may down-regulate the adhesion of memory but not naive CD4 T cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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