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1.
In the last years, granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF and GM-CSF) are being increasingly used and several cutaneous eruptions have been reported in relation to these treatments. In 1991 Horn et al. described three patients with maculopapular eruption that paralleled the time of infusion of GM-CSF. Two of the cases showed an increase in the number and size of macrophages in the biopsy specimen. Since then, several cases have been reported showing this histopathological alteration that has been considered characteristic of reaction to G-CSF or GM-CSF. Although maculopapular eruption with enlarged macrophages can appear after chemotherapy treatment, we have found that the presentation of this eruption after the beginning of cytokine treatment is suggestive of the involvement of G-CSF and GM-CSF in the eruption. We described eight cases of patients treated with G-CSF or GM-CSF that developed maculopapular eruptions with enlarged macrophages.  相似文献   
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Oocyte morphology predicts outcome of intracytoplasmic sperm injection   总被引:10,自引:14,他引:10  
To examine the influence of cytoplasmic morphology on the success rate of intracytoplasmic sperm injection (ICSI), the morphology of 837 metaphase II oocytes was assessed after cumulus stripping. The main abnormalities detected were excessive granularity, cytoplasmic inclusions such as vacuoles, smooth endoplasmic reticulum clustering and refractile bodies. Microinjection was performed in 538 oocytes with normal cytoplasm, 142 out of 161 with excessive granularity and 112 out of 138 with cytoplasmic inclusions. Very poor oocytes were not injected. No difference was found in fertilization rate. The embryos achieved cleaved normally and a similar number of good quality embryos among the three groups was noted. The outcome of transfer of embryos derived solely from normal oocytes (group A: 72 patients, 183 embryos) was compared with those from oocytes with cytoplasmic abnormalities (group B: 34 patients, 85 embryos). In group A, 17 clinical pregnancies (24% per patient, implantation rate 10%) were established. In group B, only one clinical pregnancy (3% per patient, implantation rate 1%) was established, from the transfer of embryos derived from oocytes with homogeneous granularity of the cytoplasm. No pregnancy resulted following the transfer of embryos from eggs with cytoplasmic inclusions. The difference was statistically significant. The outcome of ICSI is dependent on the quality of the oocytes retrieved. Normal fertilization and early embryo development were achieved in oocytes with abnormal cytoplasm morphology, but the resulting embryos failed to demonstrate the same implantation potential as those derived from oocytes with normal cytoplasm.   相似文献   
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Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc.  相似文献   
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Modification of the alpha-carbamate substituent of isoxazoline GPIIb/IIIa (alphaIIb beta3) antagonist DMP 754 (7) led to a series of alpha-sulfonamide and alpha-sulfamide diaminopropionate isoxazolinylacetamides which were found to be potent inhibitors of in vitro platelet aggregation. Aryl- and heteroaryl-alpha-sulfonamide groups, in conjunction with (5R)-isoxazoline (2S)-diaminopropionate stereochemistry, were found to impart a pronounced duration of antiplatelet effect in dogs, potentially due to high affinity for unactivated platelets. Isoxazolylsulfonamide 34b (DMP 802), a highly selective GPIIb/IIIa antagonist, demonstrated a prolonged duration of action after iv and po dosing and high affinity for resting and activated platelets. The prolonged antiplatelet profile of DMP 802 in dogs and the high affinity of DMP 802 for human platelets may be predictive of clinical utility as a once-daily antiplatelet agent.  相似文献   
6.
Kuypers  FA; Lubin  BH; Yee  M; Agre  P; Devaux  PF; Geldwerth  D 《Blood》1993,81(4):1051-1057
In the human erythrocyte membrane phosphatidylcholine and sphingomyelin reside mainly in the outer leaflet, whereas the aminophospholipids, phosphatidylethanolamine and phosphatidylserine, are mainly found in the inner leaflet. Maintenance of phospholipid asymmetry has been assumed to involve interactions between the aminophospholipids and the membrane skeleton, in particular spectrin. To investigate whether spectrin contributes to maintaining the phospholipid transbilayer distribution and kinetics of redistribution, we studied erythrocytes from hereditary spherocytosis patients whose spectrin levels ranged from 34% to 82% of normal. The phospholipid composition and the accessibility of membrane phospholipids to hydrolysis by phospholipases were in the normal range. Spin-labeled phosphatidylserine and phosphatidylethanolamine analogues that had been introduced into the outer leaflet were rapidly transported at 37 degrees C to the inner leaflet, whereas the redistribution of spin-labeled phosphatidylcholine was slower. The kinetics of transbilayer movement of these spin-labeled phospholipid in all samples was in the normal range and was not affected by the level of spectrin. Although these erythrocyte membranes contained as little as 34% of the normal level of spectrin and were characterized by several physical abnormalities, the composition, distribution, and transbilayer kinetics of the phospholipids were found to be normal. We therefore conclude that spectrin plays, at best, only a minor role in maintaining the distribution of erythrocyte membrane phospholipid.  相似文献   
7.
The host immune factors that determine susceptibility to HIV-1 infection are poorly understood. We compared multiple immunologic parameters in three groups of HIV-1-seronegative men: 14 highly exposed (HR10), 7 previously reported possibly to have sustained transient infection (PTI), and a control group of 14 low risk blood bank donors (BB). Virus-specific cellular immune assays were performed for CD4(+) T helper cell responses, CD8(+) cytotoxic T lymphocyte activity, CD8(+) cell chemokine release, and CD8(+) cell-derived antiviral soluble factor activity. General immune parameters evaluated included CCR5 genotype and phenotype, interferon alpha production by PBMCs, leukocyte subset analysis, and detailed T lymphocyte phenotyping. Comparisons revealed no detectable group-specific differences in measures of virus-specific immunity. However, the HR10 group differed from the BB group in several general immune parameters, having higher absolute monocyte counts, higher absolute CD8(+) T cell counts and percentages, lower naive and higher terminal effector CD8(+) cells, and lower levels of CD28(+)CD8(+) cells. These changes were not associated with seropositivity for other chronic viral infections. The PTI men appeared to have normal levels of monocytes and slightly elevated levels of CD8(+) T cells (also with increased effector and decreased naive cells). Although we cannot entirely exclude the contribution of other chronic viral infections, these findings suggest that long-lived systemic cellular antiviral immunity as detected by our assays is not a common mechanism for resistance to infection, and that resistance may be multifactorial. General immune parameters reflected by CD8(+) T cell levels and activation, and monocyte concentrations may affect the risk of infection with HIV-1, and/or serve as markers of exposure.  相似文献   
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Factor V deficiency has been identified in 8 of 8 patients 7--20 yr of age, with Philadelphia-positive (Ph1+) chronic myelogenous leukemia (CML). In these 8 patients, factor V deficiency was not due to hepatic dysfunction, factor V inhibitors, or disseminated intravascular coagulation. In 3 patients, factor V activity rose 10%--12% (0.10--0.12 U/ml) after the infusion of 28--31 ml/kg body weight of fresh frozen plasma (FFP). The rise persisted less than 14 hr. The mean measured postinfusion rise in factor V was 18% of the expected rise calculated from the volume of FFP infused in the patients' plasma volume. In 4 patients, a small transient rise in factor V activity occurred after splenectomy or plateletpheresis. Factor V deficiency was completely corrected after a marked reduction in bone marrow cellularity in 2 patients with Ph1+ CML treated with extensive chemotherapy, total body irradiation, and bone marrow transplantation. Factor V deficiency was retrospectively observed in 6 of 20 patients, ages 20--80 yr, with Ph1+ CML and 3 of 6 patients with other myeloproliferative disorders. The factor V deficiency appears to be associated with the large myeloid- megakaryocytic cell mass characteristic of CML and other myeloproliferative disorders.  相似文献   
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