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991.
The aim of this preliminary study was to investigate sleep-wake rhythm in active, healthy elderly people residing in their usual habitat. The subjects were thirty-five male volunteers within an age range of 65-95 for 3-4 days. We measured the sleep-wake rhythm of the subjects with an Actillume which is a combined wrist activity monitor and illumination recorder. Analysis of the Actillume recording showed that 24 of the 35 subjects (69%) kept continuous activity indicating good maintenance of wakefulness with high light exposure. The mean mesor of sleep-wake rhythm, however, significantly decreased in the older subjects (aged 80-95; n=15).  相似文献   
992.
BACKGROUND: The efficacy of omeprazole, 20 mg once daily, in the treatment of reflux oesophagitis and the therapeutic advantages over the histamine H2 receptor antagonists are well documented. This study assessed 20 mg omeprazole daily (OM20), 10 mg omeprazole daily (OM10), and 150 mg ranitidine (RAN) twice daily for symptom relief in gastro-oesophageal reflux disease (GORD). METHODS: Patients (n = 994) presenting with heartburn to their general practitioner underwent endoscopy to exclude peptic ulcer disease and were randomized into a UK, multicentre, parallel-group, double-blind comparison of the three treatments for 4 weeks. Symptoms were assessed at clinic visits after 2 and 4 weeks. RESULTS: Symptom relief after 4 weeks was achieved by 61% (OM20), 49% (OM10), and 40% (RAN) patients (OM20 versus OM10, P < 0.0167; OM20 versus RAN, P < 0.0001; OM10 versus RAN, P < 0.01). Among the patients (32%) with erosive reflux oesophagitis, symptom relief was achieved in 79% (OM20), 48% (OM10), and 33% (RAN) (OM20 versus OM10, P < 0.0001; OM20 versus RAN, P < 0.0001; OM1O versus RAN, NS). CONCLUSION: Omeprazole, 20 mg, is the most effective initial therapy for relief of GORD symptoms.  相似文献   
993.
A high rate of human T-lymphotropic virus type II (HTLV-II) infection has been documented in intravenous drug abusers (IVDAs) in South Vietnam. We have investigated the molecular characteristics of the virus and have shown that one HTLV-II subtype is predominant in Ho Chi Minh City. This molecular subtype, HTLV-IIb, was identified in a number of South Vietnamese by nucleotide sequence analysis of the long terminal repeat (LTR) region. HTLV-IIa was not found. These findings suggest that HTLV-IIb is endemic in IVDAs in South Vietnam, although IVDAs in urban areas in North America are predominantly infected with HTLV-IIa.  相似文献   
994.
BACKGROUND & AIMS: Recently [111In-DTPA-D-Phe1]-octreotide was approved for somatostatin receptor scintigraphy (SRS) of gastroenteropancreatic tumors. SRS and other tumor localization methods can be time consuming, expensive, and involve patient inconvenience. The role of SRS in comparison to other tumor localization modalities remains undefined because the relative effects of these methods on management have not been studied. The aim of this study was to determine whether SRS alters clinical management in Zollinger-Ellison syndrome. METHODS: One hundred twenty-two consecutive patients were studied prospectively. Each patient was assigned to one of five different clinical categories. Conventional imaging studies (ultrasonography, computerized tomography, magnetic resonance image, angiography, and bone scan) were performed, and the management was proposed. SRS was then performed. Clinical management was reassessed, and whether SRS altered management was determined based on six criteria. RESULTS: SRS was superior to any single imaging study. SRS altered management in 47% overall and in 22%-60% of patients in the five different clinical categories. Primary tumor localization and clarification of equivocal localization results from conventional studies were the principal reasons for altering management. SRS was equally useful in patients with or without metastatic liver disease. CONCLUSIONS: Because of the ability of SRS to alter clinical management combined with its superior sensitivity, high specificity, simplicity, and cost-effectiveness, SRS should be the initial imaging modality for patients with gastrinomas.  相似文献   
995.
996.
The authors report surface impedance measurements made on a cylindrical cavity resonator constructed entirely from the sintered high temperature superconductor YBa2Cu3O7, and have measured the temperature dependence of the surface impedance for five different modes in the frequency range 10-18 GHz, in the temperature range form 4-300 K  相似文献   
997.
Mammography, which is the first-choice examination for breast disease, has some limitations despite recent technical improvement, which has lead to better image quality and reduced x-ray exposure. It is less accurate in dense breasts, which are sometimes difficult to read and in which a palpable lesion or an infraclinical cancer is often not recognized. In such cases, ultrasonography is very useful and should be used as the second examination technique. Breast sonography done by a skilled sonographer with a good equipment can raise the accuracy for benign or malignant breast lesions.  相似文献   
998.
Two human squamous cell carcinoma of the head and neck (SCCHN) cell lines, PCI-13 and PCI-52, were transduced with the retroviral construct containing human interleukin-2 (IL-2) cDNA and selected for neomycin resistance in G418 medium. Stably transduced SCCHN cells produced and secreted IL-2, which was shown to have biologic activity in a bioassay, using an IL-2-dependent CTLL-2 cell line. By immunohistochemistry, IL-2 gene-transduced PCI-13 cells were strongly positive for IL-2, and by flow cytometry showed both cell surface and intracytoplasmic expression of IL-2 protein. Expression of IL-2 mRNA was measured by quantitative RT-PCR and found to be considerably increased in transduced SCCHN relative to that in parental cells. There was no difference in expression of IL-2R between the parental and IL-2 gene-transduced cells. In vitro proliferation of IL-2 gene-transduced tumor cells was consistently more rapid than that of parental cells. Sensitivity of the parental and IL-2 gene-transduced targets to lysis or apoptosis mediated by purified human natural killer (NK) cells or IL-2-activated NK (A-NK) cells was comparable as measured in 4-hour 51Cr-release and 1-hour [3H]thymidine-release assays, respectively. However, transduced cells were significantly more sensitive than parental cells to these effectors in 24-hour MTT assays, most likely due to IL-2 production by the transduced targets. PCI-52 cells selected for in vivo experiments formed large subcutaneous tumors in immunosuppressed nude mice. Tumors established by subcutaneous injections of 1 x 10(7) IL-2 gene-transduced cells regressed completely by day 25, while those formed by parental or LacZ gene-transduced tumor cells grew progressively. Tumor regression was mediated by numerous mononuclear cells, identified as murine NK cells and macrophages by immunohistochemistry, which accumulated around the IL-2-secreting, but not parental, tumors within 5-6 days after tumor cell injections. Thus, IL-2 gene-transduced SCCHN cells produce functional IL-2 in vivo in amounts sufficient to support the recruitment to the tumor site and antitumor activity of cytotoxic effector cells. IL-2-secreting SCCHN cells may be a useful component of vaccines designed to induce and sustain effector cell activation at the tumor site.  相似文献   
999.
Within a few years of the invention of the telephone, many police forces around the world immediately embraced the new technology in the ever increasing fight against crime. By the turn of the 19th century police telephone boxes were appearing on city streets for the use of officers and the general public and by the early 1930s there were a few thousand boxes in the UK. By the late 1960s, however, the the advances in telecommunications resulted in the signal boxes being surplus to police requirements and most were removed. This paper looks at the history of police telephonic communications, and in particular at the creation of Glasgow's network, which was one of the largest in the UK, with 323 on-street police signal boxes  相似文献   
1000.
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