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31.
Cytogenetic and clinical data of 11 patients with de novo myelodysplastic syndromes and partial or total trisomy of the long arm of chromosome 1 are presented. In eight of these patients trisomy 1q was the sole karyotypic change and therefore can be classified as a primary chromosome anomaly. A remarkably young median age of 36.5 years was noticed in this patient group.  相似文献   
32.
Autoimmune (type 1) diabetes mellitus in mouse, rat, and humans shares several features, including T lymphocyte infiltration into pancreatic islets and a dependence on permissive class II major histocompatibility complex (MHC) alleles. We report here on an experimental model involving mice that express influenza hemagglutinin (HA) under the control of the insulin promoter and, at the same time, a transgenic class II MHC-restricted T cell receptor (TcR) specific for an HA peptide. These mice spontaneously develop islet infiltrates resembling those found in NOD mice and most animals become diabetic within 8 weeks of age. Because of the availability of a clonotypic TcR antibody, we can be confident that the Ins-HA transgene does not induce any measurable alterations in the vast majority of T cells with the transgenic TcR in primary and secondary lymphoid organs. Continuous export of large numbers of HA-specific lymphocytes from the thymus was not required for the manifestation of the disease since mice thymectomized at 3 days after birth still developed the disease albeit with smaller infiltrates.  相似文献   
33.
Summary We studied the efficacy and tolerability of a repeatable long-acting parenteral depot-bromocriptine preparation (Parlodel LAR) in 14 acromegalic patients, 10 of whom had received oral bromocriptine therapy previously, 2 of them showing intolerance to oral bromocriptine. Patients received i.m. injections of 50–100 mg depot-bromocriptine at 4-week intervals for 3–24 months (median 6). Growth hormone profiles were assessed by four daily samples at 4-week intervals. Main daily growth hormone levels decreased from 52.1 ±12.3 g/l (mean ± SEM) to 19.4 ± 4.7 g/l on the day of injection. In 6 patients, growth hormone values were lowered by more than 50%, whereas IGF-I levels decreased only slightly and growth hormone values during the oral glucose tolerance test remained non-suppressible. Tumour sizes were not affected. Two women became pregnant and were delivered of healthy babies. Side-effects typical of bromocriptine occurred frequently on the days of injection and diminished in most patients after 2 months of therapy despite increasing dosage. Compared with previous oral bromocriptine therapy, 9 of 10 patients preferred the depot preparation, whereas the reduction of growth hormone levels was similar during both treatments. In conclusion, depot-bromocriptine should be considered for acromegalic patients intolerant to oral bromocriptine.Abbreviations br Bromocriptine - oral br. oral bromocriptine - depot-br. depot-bromocriptine - GH growth hormone - oGTT oral glucose tolerance test - GnRH gonadotropin-releasing hormone - TRH thyrotropin-releasing hormone  相似文献   
34.
An investigation on the molecular dynamics of a liquid crystalline side chain polymer using the dielectric relaxation method on oriented samples in the frequency range of 0,1 to 10 000 kHz is presented. The compound under investigation is a polysiloxane copolymer with two different mesogenic side chains and a phase sequence glassy-smectic A-nematic-isotropic. Three main relaxation processes are found and assigned to the rotation of the side chains around the main chain, the glass transition process coupled with side chain motions, and a local motion in the glassy state, respectively. Evidence is found for a layered arrangement of the polymer main chain in the smectic phase and for a parallel correlation between the transverse components of the dipole moments.  相似文献   
35.
Coronary calcification is a strong predictor of significant coronary stenosis in symptomatic patients. While discrete calcification within coronary arteries is only detected by sensitive methods such as computed tomography, severe calcification can already be seen on the plain chest radiograph. In this article, we describe a patient with a high grade left main stem coronary artery stenosis who presented with a severe focal calcification on the plain chest radiograph in projection of the offspring of the left coronary artery.  相似文献   
36.
In low-income countries there are few data on hospital malnutrition. Reduced food intake combined with nutrient-poor foods served in hospitals contribute to nutritional risk. This study investigated whether reported dietary intake and disease state of hospitalized adults in critical care units was related to malnutrition determined by mid-upper arm circumference (MUAC). Adult in-patients (n = 126) in tuberculosis, burn, oncology, and intensive care units in two public tertiary hospitals in Malawi were screened for nutritional status using MUAC and a question on current dietary intake. The hospital menu was reviewed; portion sizes were weighed. The prevalence of moderate and severe malnutrition was 62%. Patients with organ-related diseases and infectious diseases had the highest rates of reduced reported dietary intake, 71.4% and 57.9%, respectively; however, there was no association between reported dietary intake and MUAC. In those unable to eat, however, the rate of severe malnutrition was 50%. The menu consisted of porridge and thickened corn-based starch with fried cabbage; protein foods were provided twice weekly. There was a nutrient gap of 250 calories and 13 gm protein daily. The findings support the need for increasing dietetic/nutrition services to prevent and treat malnutrition in hospitals using simple screening tools.  相似文献   
37.
The sodium/calcium exchanger was purified from bovine retinal rod outer segment membranes and used for the immunization of New Zealand White rabbits. A polyclonal antibody was produced which was found to bind specifically to the 230 kDa Na+/Ca2(+)-exchanger protein as assessed by Western blotting. The antibody did not bind to the high-molecular-weight "rim protein," thereby demonstrating that this protein is distinct from the rod outer segment of Na+/Ca2(+)-exchanger. We used the polyclonal antibody for immunohistochemically localizing the exchange protein in bovine retina. Fluorescent light microscopy revealed intensive immunolabeling of the photoreceptor outer segments, whereas other retinal cell layers exhibited minimal binding. Using the electron microscopic immunogold method, we found specific antibody binding to the extracellular side of rod outer segment plasma membrane. Rod disk membranes, rod inner segments, and cone photoreceptors displayed no significant labeling. We therefore conclude that the Na+/Ca2(+)-exchanger is localized primarily in the rod outer segment plasma membrane, the most appropriate localization considering its proposed role in the process of vertebrate phototransduction.  相似文献   
38.
From June 1986 to December 1988, 107 patients (median age, 49 years; median performance score, 1) with haematogeneous metastases from breast carcinoma were treated with concomitant radiation and chemotherapy. Overall, 97% of the patients had been pretreated with surgery; 65%, with radiation; and 56%, with hormones. In all, 38% had received adjuvant chemotherapy. Patients with prior palliative chemotherapy were excluded from the study. All patients fulfilled at least two high-risk criteria. Chemotherapy was given according to the EI protocol (4-epirubicin and ifosfamide), and all patients simultaneously received radiation to the main tumor sites. Gastro-intestinal toxicity was moderate (11.1%, WHO grade 4), and bone marrow depression was marked in all cases. After three treatment courses, the overall response rate was 67% [21% complete response (CR), 46% partial response (PR)]. In all, 28% had stable disease (NC) and the rate of progressive disease (PD) was 5%. The median duration of tumour response was 8 months, with 12 months for CRs, 9 months for PRs and 6 months for NCs. The median survival was 13.5 months.Presented at the Satellite Symposium Ifosfamide in Gynecological Tumors of the 5th European Conference on Clinical Oncology and Cancer Nursing', London, September 3–7, 1989  相似文献   
39.
Purpose: To demonstrate the feasibility of a technique for the visualization by scanning laser ophthalmoscope (SLO) of fluores cein-labelled autologous leukocytes and platelets in retinal vessels. Method: Individual blood samples from rats and rabbits were centrifuged to isolate platelets and leukocytes, then passively labelled with fluorescein and reinjected into the same animal. An SLO was used to visualize and record cell displacement in the retinal circulation. Labelled platelets were analysed by flow cytometry. Results: By SLO, platelets appeared as a heterogeneous particle flow, and individual leukocytes appearing as brighter spots could easily be traced. Flow cytometry showed that after labelling platelets were well individualized and their size was slightly increased. Conclusion: Circulating blood cells can be visualized in retinal vessels by a simple method consisting of passive labelling of autologous platelets and leukocytes by fluorescein. No platelet toxicity was detected. This method could be applied to the study of blood cell movement in human retinal vascular diseases.Proprietary interest category: N  相似文献   
40.
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