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991.
Despite significant progress in cryopreservation of mammalian oocytes and embryos, many ofthe molecular and biochemical events that underlie this technology are poorly understood. In recent years, researchers have focused on obtaining viable oocytes that are developmentally competent. Even under the most favourable conditions, experimental approaches have achieved only limited success compared with fresh oocytes used in routine in vitro embryo production. Chilling injuries and toxic effects of the cryoprotectants are the major adverse consequences following cryoprocedures. To overcome these problems, different strategies have been developed for improving cryopreservation results. These strategies include reducing container volumes, increasing the thermal gradient, changing the cell surface/volume ratio, enhancing cryotolerance by supplementation with various additives or modifying the lipid composition of the oocyte membrane. In order to develop new strategies for reducing the various forms of stress associated with oocyte cryopreservation, it is fundamental to gain a better understanding of the major changes responsible for poor post-thaw survival. With this knowledge, we hope that oocyte cryostorage will become a fully reliable reproductive technique in the near future.  相似文献   
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BACKGROUND: Decitabine is a hypomethylating agent that has activity in patients with leukemia. The authors combined decitabine with busulfan and cyclophosphamide as a conditioning regimen prior to allogeneic hematopoietic stem cell transplantation. METHODS: Patients with high-risk acute myeloid leukemia (AML) (n = 12 patients); chronic myelomonocytic leukemia (CMML) (n = 1 patient); acute lymphocytic leukemia (ALL) (n = 1 patient); or late chronic phase, accelerated, or blastic phase chronic myelogenous leukemia (n = 9 patients) were eligible for the study. The treatment plan was comprised of busulfan, 12 mg/kg orally; cyclophosphamide, 100 mg/kg (n = 4 patients) or 120 mg/kg (n = 19 patients); and decitabine, intravenously at 3 dose levels: 400 mg/m(2) (n = 10 patients), 600 mg/m(2) (n = 8 patients), and 800 mg/m(2) (n = 5 patients). Donors were human leukocyte antigen-identical siblings in all cases, and all but one patient received peripheral blood stem cells. Graft-versus-host disease (GVHD) prophylaxis was tacrolimus based in all but one patient. RESULTS: The median time to neutrophil and platelet engraftment was 12.5 days and 17.5 days, respectively. Twenty-one patients were engrafted and achieved disease remission. At a median of 3.3 years posttransplantation, 26% of patients (40% of patients with AML) were alive and disease free. The median survival for the group was 17.2 months, and the disease free survival for the group was 8.9 months. Causes of death were disease recurrence (nine patients), chronic GVHD (four patients), infections (three patients), and acute GVHD (one patient). The 100-day mortality rate was 9%. No decitabine dose-limiting toxicity was documented. The treatment-related mortality rate at 3 years was 35%. Responders were treated at all three decitabine dose levels, and no dose-response correlation was observed. CONCLUSIONS: There was a high response rate with low treatment-related mortality, with 26% of patients alive in remission 3.3 years after transplantation.  相似文献   
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Purpose. To assess the response rate, survival, and toxicity of Taxol®(paclitaxel) as 1h infusion plus doxorubicin as firstline treatment for patients with metastatic breast cancer (MBC).Patients and methods. Seventysix patients with untreated MBC were recruited. All of them had measurable disease and were evaluable for toxicity. Fiftyfive percent of the patients had visceral involvement. The dose of doxorubicin was fixed at 50mg/m2 as a short intravenous infusion, followed by 200mg/m2 of Taxol as a 1h intravenous infusion. Doxorubicin was administered during the first seven cycles, continuing with Taxol only up to a maximum of ten cycles.Results. Neutropenia was the most important toxicity: 30% grade 3 and 18% grade 4. Only 2 patients showed a decrease in the left ventricular ejection fraction (LVEF) which caused discontinuing the treatment. No clinical congestive heart failure (CHF) was observed. Seventyfour patients were eligible for response evaluation: 10 (14%) achieved complete response (CR) and 46 (62%) achieved partial response (PR). The mean duration of response was 13.47± 1.35 months (95% confidence interval (CI): 10.82; 16.12) and the mean survival was 21.50± 1.42 months (95% CI: 18.72; 24.29).Conclusion. The overall response (OR) rate was 76%. No CHF was assessed and 2 patients stopped treatment due to LVEF decrease. Although doxorubicin 50mg/m2 followed by Taxol 200mg/m2 in 1h intravenous infusion presents a toxicity profile which demands a close followup, it represents a convenient outpatient schedule with similar activity rate compared to longer Taxol infusions.  相似文献   
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The present study reports the distribution of Neuropeptide Y (NPY)-immunoreactive neurons and fibers in the forebrain of the adult carp Cyprinus carpio L.. Serial Nissl-stained sections were used for cytoarchitecture and identification of anatomical structures. Immunostaining of NPY-containing neurons and fibers was used as neurochemical marker and tool for comparison with other species, including the goldfish.The general outline of the cytoarchitecture of the carp forebrain is similar to that of other Cypriniformes. However, using NPY immunohistochemistry, we found several specific differences with the goldfish, especially in the diencephalon. In the hypothalamus of the carp NPY-immunoreactive (NPYir) neurons were identified in the n. dorsolateralis thalami, and in the n. ventralis lateralis thalami. In the same location, we observed the n. anterior hypothalami and the n. preglomerulosus pars lateralis, described in the goldfish, as parts of n. prerotundus. However, in the carp we were not able to identify a n. preglomerulosus pars medialis, a n. preglomerulosus pars medialis commissuralis and a n. glomerulosus. We describe a n. rotundus, in which we did not find substructures typical of the goldfish.Further differences with the goldfish, trout and salmon were also noted.  相似文献   
997.
Expression of cytoplasmic islet cell antigens by rat pancreas   总被引:2,自引:0,他引:2  
A major problem in standardization of the islet cell cytoplasmic antibody (ICA) assay is variation in sensitivity of the different human pancreas substrates used in individual laboratories. To circumvent this problem, we have developed an assay that utilizes Wistar-Furth rat pancreas as substrate, an anti-islet monoclonal antibody (A2B5) to identify islets and fluorescein-conjugated protein A to identify patient autoantibodies. Sera from 85 control subjects, 27 type I diabetics, and 17 subjects at high risk for developing type I diabetes were assayed in parallel with our standard ICA assay on human pancreas substrate and with Wistar-Furth rat pancreas as substrate. Two sera from control subjects (2 of 85) were ICA positive with rat pancreas compared to 1 of 85 with human pancreas substrate. Sera from 11 of 27 type I diabetics and 15 of 17 sera from high-risk subjects were ICA positive with either rat or human pancreas substrate. A correlation between the specific islet fluorescence readings on human and rat pancreas sections was found with sera from high-risk and control subjects. Furthermore, end-point titers of an ICA-positive serum were identical with both assays. Finally, incubation of an ICA-positive serum with glycolipids, extracted from either human or Wistar-Furth rat pancreas, blocked subsequent ICA binding. These findings suggest that Wistar-Furth rat pancreas expresses an identical or similar autoantigen to human pancreas.  相似文献   
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Apathy is a common condition in Parkinson's disease (PD) and is generally defined as a lack of motivation. It is associated with more severe cognitive dysfunction and a decrease in activities of daily living (ADL) performance. Anhedonia, the inability to experience pleasure, can be a symptom of both depressive and apathetic syndromes. The Movement Disorder Society (MDS) commissioned a task force to assess the clinimetric properties of apathy and anhedonia scales in PD patients. A systematic literature review was conducted to identify scales that have either been validated or used in PD patients. Apathy scales identified for review include the Apathy Evaluation Scale (AES), the Apathy Scale (AS), the Apathy Inventory (AI), and the Lille Apathy Rating Scale (LARS). In addition, item 4 (motivation/initiative) of the Unified Parkinson's Disease Rating Scale (UPDRS) and item 7 (apathy) of the Neuropsychiatric Inventory (NPI) were included. Anhedonia scales identified for review were the Snaith‐Hamilton Pleasure Scale (SHAPS) and the Chapman scales for physical and social anhedonia. Only the AS is classified as “recommended” to assess apathy in PD. Although item 4 of the UPDRS also meets the criteria to be classified as recommended, it should be considered for screening only because of the obvious limitations of a single item construct. For the assessment of anhedonia, only the SHAPS meets the criteria of “Suggested.” Information on the validity of apathy and anhedonia scales is limited because of the lack of consensus on diagnostic criteria for these conditions. © 2008 Movement Disorder Society  相似文献   
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