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991.
PURPOSE: To assess the effect of ambulatory teaching on patients' satisfaction. METHOD: In 1996, 103 adult patients presenting to the Walter Reed General Medicine Walk-in Clinic completed a patient-satisfaction questionnaire immediately following their visits, during which they were initially seen by a trainee (third-year medical student or intern) and then seen by a faculty preceptor. The questionnaire included five items from the validated Medical Outcomes Study (MOS)-9 questionnaire as well as two open-ended questions. Fourteen staff physicians, 13 students (49% of the visits), and 11 interns (51% of the visits) participated in the study. Satisfaction was analyzed by level of training, and the responses from the study patients were compared with the responses from 372 usual-care (i.e., non-teaching) patients from the same clinic, using the chi-squared test. RESULTS: The study patients were typically pleased with their encounters, rating their overall satisfaction as excellent (61%), very good (29%), or good (9%). Nearly two thirds of the patients rated their satisfaction with waiting time to be very good or excellent. Compared with the usual-care patients, the study patients reported equal or greater satisfaction for all five MOS-9 items. Ninety-five percent of the study patients said they would be willing to be seen by a trainee-staff team on future visits. There was no difference in patient satisfaction by trainee level. The study patients cited enhanced interaction (45%), enhanced education (34%), and improved care (26%) as benefits of trainee-involved care, and increased waiting time (18%) and worse care (5%) as drawbacks. CONCLUSION: The results of this study suggest that ambulatory teaching does not adversely affect patient satisfaction, regardless of trainee level, and that patients who have been seen by trainee-staff teams are willing to experience such encounters again.  相似文献   
992.
The development of Schwann cells, the myelin-forming glial cells of the vertebrate peripheral nervous system, involves a neonatal phase of proliferation in which cells migrate along and segregate newly formed axons. Withdrawal from the cell cycle, around postnatal days 2-4 in rodents, initiates terminal differentiation to the myelinating state. During this time, Schwann cell number is subject to stringent regulation such that within the first postnatal week, axons and myelinating Schwann cells attain the one-to-one relationship characteristic of the mature nerve. The mechanisms that underly this developmental control remain largely undefined. In this report, we examine the role of apoptosis in the determination of postnatal Schwann cell number. We find that Schwann cells isolated from postnatal day 3 rat sciatic nerve undergo apoptosis in vitro upon serum withdrawal and that Schwann cell death can be prevented by beta forms of neuregulin (NRG-beta) but not by fibroblast growth factor 2 or platelet-derived growth factors AA and BB. This NRG-beta-mediated Schwann cell survival is apparently transduced through an ErbB2/ErbB3 receptor heterodimer. We also provide evidence that postnatal Schwann cells undergo developmentally regulated apoptosis in vivo. Together with other recent findings, these results suggest that Schwann cell apoptosis may play an important role in peripheral nerve development and that Schwann cell survival may be regulated by access to axonally derived NRG.  相似文献   
993.
Retinoids are important regulators of cell growth and differentiation in vitro and in vivo and they exert their biologic activities by binding to nuclear retinoic acid receptors (RARs; alpha, beta, and gamma) and retinoid X receptors (RXRs; alpha, beta, and gamma). All-trans retinoic acid (RA) induces complete remission in patients with acute promyelocytic leukemia (APL) presumably by binding directly to RAR alpha of APL cells. Leukemic blasts from APL patients initially responsive to RA can become resistant to the agent. HL-60 myeloblasts cultured with RA have developed mutations of the ligand-binding region of RAR alpha and have become resistant to RA. Furthermore, insertion of an RAR alpha with an alteration in the ligand-binding region into normal murine bone marrow cells can result in growth factor-dependent immortalization of the early hematopoietic cells. To determine if alterations of the ligand binding domain of RAR alpha might be involved in several malignant hematologic disorders, the mutational status of this region (exons 7, 8, and 9) was examined in 118 samples that included a variety of cell lines and fresh cells from patients with myelodysplastic syndromes (MDS) and acute myeloid leukemias (AML), including 20 APL patients, 5 of whom were resistant to RA and 1 who was refractory to RA at diagnosis, using polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) analysis and DNA sequencing. In addition, 7 of the 20 APLs were studied for alterations of the other coding exons of the gene (exons 2 through 6). No mutations of RAR alpha were detected. Although the sensitivity of PCR-SSCP analysis is less than 100%, these findings suggest that alterations of RAR alpha gene are rare and therefore other mechanisms must be involved in the onset of resistance to retinoids and in the lack of differentiation in disorders of the myeloid lineage.  相似文献   
994.
A professional musician with intolerable hyperacusis and dysharmonic diplacusis in a severely deafened ear was successfully relieved of his symptoms by deliberate destruction of the cochlea.  相似文献   
995.
A pilot study on the percutaneous introduction of a cecostomy tube for colonic irrigations in the treatment of children with fecal incontinence is described. The results were good, and the technique is recommended for certain patients.  相似文献   
996.
Antidepressant effects of mirtazapine and imipramine were compared in a randomized, double blind, fixed blood-levels study with in-patients in a single centre. Patients with a DSM-III-R diagnosis of major depression and a Hamilton (17-item) score of > or = 18 were selected. After a drug-free and a placebo-washout period of 7 days in total, 107 patients still fulfilling the HRSD criterion of > or = 18, started on active treatment. The dose was adjusted to a predefined fixed blood level to avoid suboptimal dosing of imipramine. Concomitant psychotropic medication was administered only in a few cases because of intolerable anxiety or intolerable psychotic symptoms. Eight patients dropped out and two were excluded from analyses because of non-compliance; 97 completed the study. According to the main response criterion (50% or more reduction on the HRSD score) 11/51 (21.6%) patients responded on mirtazapine and 23/46 (50%) on imipramine after 4 weeks' treatment on the predefined blood level. Such a dramatic difference in efficacy between antidepressants has not often been reported before. The selection of (severely ill) in-patients, including those with suicidal or psychotic features, may have significance in this respect. Optimization of treatment with the reference drug imipramine through blood level control, exclusion of non-compliance for both drugs, exclusion of most concomitant medication and a low drop-out rate may also have contributed. It is concluded that imipramine is superior to mirtazapine in the patient population studied.  相似文献   
997.
998.
BACKGROUND: Extracorporeal photopheresis is a pheresis-based therapy that permits the direct targeting of psoralen-mediated photochemotherapy to circulating pathogenic T cells. Although photopheresis is currently used to treat cutaneous T-cell lymphoma (CTCL), limited data are available regarding overall response rates and durability of responses among patients with advanced disease. Furthermore, little is known about the effectiveness and tolerability of combined regimens employing other biologic response modifiers including interferon alfa. OBJECTIVE: Our purpose was to determine the efficacy of photopheresis among 41 patients with the clinical and laboratory diagnosis of CTCL; the majority of patients had stage III or IV disease with the presence of circulating malignant T cells. METHODS: A retrospective chart review during a 10-year period at a single university hospital was performed for all patients receiving either photopheresis monotherapy on two consecutive days every 4 weeks (one cycle) and for an additional 12 patients who also received interferon alfa 1.5 to 5 million U subcutaneously three to five times weekly. RESULTS: Thirty-one of 41 patients (76%) were treated for six or more cycles. The remaining 10 were treated with less than six cycles because of rapidly progressing disease (n = 6), death unrelated to CTCL (n = 2), or withdrawal from treatment (n = 1); one of the 10 patients had only received five cycles of treatment but is still receiving therapy. Twenty-eight of the 31 patients treated for six or more cycles received photopheresis alone. Among the 28, seven patients (25%) had a complete remission, 13 (46%) had a partial remission defined as more than 50% clearing of skin disease, and eight (29%) did not respond to treatment. The presence of Sézary cells in the peripheral blood was associated with a favorable response. Median time to treatment failure was 18 months, whereas median survival from initiation of therapy was 77 months and from the time of diagnosis exceeded 100 months. Nine of these 28 patients went on to receive combination therapy with interferon alfa and, in some cases, other agents. Among these nine patients, five had an enhanced clinical response to the combination therapy compared with treatment with photopheresis monotherapy. The combined regimen was well tolerated. CONCLUSION: These results indicate that patients with advanced CTCL can achieve a high response rate for an extended period with photopheresis and that interferon alfa combined with photopheresis is a well-tolerated regimen that appears to produce higher response rates than photopheresis alone.  相似文献   
999.
1000.
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