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91.
Groups of day-old chicks with varying levels of parental antibody were vaccinated against Newcastle disease (B1 strain) with a commercially available device which simultaneously debeaks the chick and emits a fine spray of vaccine into its trachea. Some groups were also vaccinated (B1 or Lasota strain) with a commercially available vaccine sprayer at 9 days, 14 days, or 9 and 25 days of age. Response to vaccine was evaluated once each week during the experimental period of approximately 8 weeks HI titers were determined and 10 chicks were challenged with the Texas GB strain of Newcastle disease virus. In chicks with low to moderate levels of maternal antibody a satisfactory antibody response was attained by vaccination at 1 day of age, and in most cases resistance to challenge was evident by 3 weeks of age. Intratracheal vaccination of chicks with extremely high levels of maternal antibody had a minimal antibody response. All groups of chicks spray vaccinated at 9, 14, or 9 and 25 days of age showed a marked increase in antibody titer regardless of whether they had been vaccinated at 1 day of age.  相似文献   
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OBJECTIVE: To evaluate the efficacy of tramadol as adjunctive therapy in patients with musculoskeletal pain attributed to osteoarthritis (OA) who experienced breakthrough pain while taking a nonsteroidal antiinflammatory drug (NSAID). METHODS: This single center, parallel, placebo controlled, 2 phase study was conducted in adults who experienced breakthrough OA pain while undergoing stable NSAID therapy. In a 24 h open label phase, patients took 100 mg of tramadol followed by 50 mg every 6 h (total 250 mg) in addition to their daily NSAID regimen. Supplemental analgesics were prohibited. Patients who met entry criteria and were willing to continue therapy were randomized to a 13 day double blind phase of adjunctive therapy with tramadol (50-100 mg every 4-6 h as needed for pain) or placebo; NSAID therapy was continued. The primary efficacy endpoint was the time to exit from the study because of therapeutic failure (i.e., insufficient pain relief or an inability to perform activities of daily living). RESULTS: The time to exit from the study because of insufficient pain relief tended to be longer in the tramadol group (250 mg/day) compared with the placebo group (p = 0.066). At the end of the double blind phase, pain at rest was significantly less severe in tramadol treated patients (p = 0.046). In addition, severity of pain on motion tended to be less severe in tramadol treated patients (p = 0.059). General severity of current pain and ability to perform activities of daily living were not significantly different with tramadol or placebo. Patients' overall assessment of therapy (p = 0.022) and investigator's rating of global improvement (p = 0.004) were significantly better with tramadol than with placebo. CONCLUSION: Tramadol may have a role as adjunctive treatment for breakthrough pain in patients receiving NSAID therapy for musculoskeletal pain attributed to OA.  相似文献   
94.
The authors compared in a controlled clinical study two groups of patients after a first renal transplantation treated by triple drug immunosuppressive therapy. In a group of 31 patients the triple combination comprised Sandimmune Neoral. In the control group there were 30 patients who received Sandimmune. No differences were found between the two groups as regards the effectiveness of this treatment and the authors did not confirm a lower incidence of rejections described in patients treated with Sandimmune Neoral. They confirmed, however, a lower interindividual variability of Cy-A levels assessed specifically in patients treated with Sandimmune Neoral.  相似文献   
95.
Fifty-five patients (61 affected hips and 49 unaffected hips) with Perthes disease were reviewed to evaluate the relationship between widening of medial joint space and lateral subluxation of the femoral head in radiographs. The components of the medial joint space were evaluated by using T1, T2, proton, and Gd-enhanced T1WI magnetic resonance images (MRI). The widened medial joint space in radiographs was filled with overgrown cartilage at the initial stage (27 hips) in MRI, with both overgrown cartilage and widened true medial joint space at the fragmentation stage (23 hips) and widened true medial joint space at the healing stage (11 hips). Between affected hips and unaffected hips, the mean difference of medial joint space in radiographs between hips at the initial stage and at the fragmentation stage was 2 and 4.5 mm, respectively; the mean difference in percentage of lack of coverage of the femoral head between hips at the initial stage and at the fragmentation stage was 3 and 15%, respectively. During the healing stage, widening of the medial joint space decreased or normalized because of ossification of overgrown cartilage despite the existence of lateral subluxation because of coxa magna. We concluded that widening of the medial joint space may be used as an index of lateral subluxation at only the fragmentation stage in Perthes disease.  相似文献   
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OBJECTIVE: To estimate the prevalence of radiographically detectable hippocampal atrophy (HA) in a normal aging sample and to test whether such atrophy is associated with memory dysfunction. DESIGN: One hundred fifty-four medically healthy and cognitively normal elderly persons (aged 55 to 88 years) received magnetic resonance imaging and/or computed tomographic scans designed to identify HA. One hundred forty-five of these subjects also underwent psychometric tests of memory function. Multivariate analyses of variance were used to evaluate differences in memory performance between subjects with and without HA. SETTING: This study was conducted at a research clinic for the investigation of age-associated neuropsychological and neuroradiologic changes. PARTICIPANTS: Based on the following criteria, 154 subjects were consecutively selected from a larger group of elderly research volunteers participating in a study of normal aging: age of 55 years or greater; Global Deterioration Scale score of 2 or less; and Mini-Mental State examination score of 28 or greater. Subjects with evidence for significant medical, psychiatric, or neurologic disease were excluded. MAIN OUTCOME MEASURES: Outcome measurements included individual psychometric test scores and computed tomographic-magnetic resonance imaging hippocampal atrophy ratings. RESULTS: Nearly 33% of the subjects had radiographic evidence for HA. The prevalence of HA increased significantly with age and was more common in male than female subjects. After controlling for age, level of education, and vocabulary, subjects with HA were found to perform more poorly on tests of recent (secondary) verbal memory when compared with subjects without HA (P < .01). No significant differences were found for tests of immediate (primary) memory. CONCLUSION: We conclude that HA is a common accompaniment of normal aging and is associated with mild memory impairment. Additional research is needed to determine whether HA constitutes a significant risk for future dementia.  相似文献   
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BACKGROUND: The evidence-based approach to medical care involves the explicit use of evidence on the magnitude of the effects of interventions to inform diagnostic and treatment decisions. This article critiques current mainstream guidelines on the management of hypertension in the elderly (aged 60 years and over) and presents an alternative evidence-based approach. METHODS: Three major national and international guidelines for the management of hypertension from the United Kingdom (UK), the United States (US) and from a joint World Health Organisation/International Society of Hypertension (WHO/ISH) Working Party were appraised and the evidence on which they were based was reviewed. The relevant evidence was also assessed to determine the likely magnitude of risks and benefits of anti-hypertensive treatment in older people and an alternative approach to making treatment decisions, based on the New Zealand guidelines for the management of hypertension, is described. RESULTS: Hypertension management guidelines from the UK, US and WHO/ISH made similar recommendations about which elderly patients should be treated, although there were some ambiguities in their advice. Treatment recommendations were based primarily on blood pressure levels which were set at about 160 mm Hg systolic and/or 90 mm Hg diastolic. The threshold levels were based mainly on the cut-off blood pressure levels used in randomised trials of anti-hypertensive drug treatment, rather than the estimated magnitude of treatment benefit. Each of the guidelines acknowledged the important effect of associated cardiovascular disease (CVD) risk factors on the likely benefits of treatment, but did not expand on the magnitude of this effect. No patient-specific estimates of the likely absolute benefits of treatment were provided in any of the guidelines. In contrast the New Zealand guidelines for the management of hypertension recommend the use of explicit estimates of absolute CVD risks and benefits to inform treatment decisions. They were designed to provide practitioners with estimates of the likely absolute risk of CVD in patients with different risk factor profiles and with estimates of the absolute benefits of treatment. The New Zealand guidelines recommend that drug treatment be considered in patients with a 5-year risk of CVD of about 10-15% or more; approximately 25 patients with a 10-15% risk would require treatment for 5 years to prevent one CVD event. As elderly patients are generally at higher absolute CVD risk than younger people, the New Zealand recommendation give priority to the treatment of older patients. In order to take account of differences in life expectancy and the medical costs of caring for elderly people, absolute risk-based guidelines can be improved by incorporating potential years of life gained from treatment and the cost-effectiveness of treatment expressed as $/quality adjusted life years gained. Preliminary analyses indicate that the cost-effectiveness of treatment is generally greatest in patients in their 60s and early 70s. Treatment in younger people is not usually very cost-effective because of their low absolute risk of CVD and the cost-effectiveness of treatment in people over about 75 years declines because of the increasing cost of non-CVD morbidity. CONCLUSIONS: The explicit assessment of absolute CVD risks and likely treatment benefits in patients with hypertension can usefully inform treatment decisions and provide a more rational basis for initiating therapy than blood pressure levels alone. This approach highlights the generally greater CVD risk and potential treatment benefits in older compared with younger hypertensive patients. The absolute risk-based approach can be further enhanced by providing decision makers with patient-specific data on the potential life years gained from treatment and its cost-effectiveness. (ABSTRACT TRUNCATED)  相似文献   
100.
1. Paracetamol is increasingly involved in self-poisoning in the United Kingdom and remains a common cause of fatal poisoning. 2. To document the epidemiology and early management of paracetamol poisoning data were collected on consecutive patients with suspected paracetamol poisoning presenting to 6 hospitals in the North East of England over 12 weeks in 1994. 3. There were 400 presentations (attendance rate 1.14/10(3) population/yr) involving 343 persons (45% male). Paracetamol concentrations at 4 h correlated weakly with reported paracetamol dose (R = 0.49, P < 0.0001) and were similar comparing those treated and not treated by gastric decontamination. 4. In 38 (9%) cases paracetamol concentrations were above the appropriate nomogram treatment line, including 3% and 20% of patients who reported ingesting less than and more than 12 g respectively. In 21 patients acetylcysteine treatment was deferred until admission to the ward, the mean delay involved was 2.8 h. 5. One patient died, from arrhythmias caused by co-ingested dothiepin. 6. Paracetamol poisoning is common. Most cases do not have potentially toxic plasma paracetamol concentrations, but those who do often present late and antidotal treatment may be delayed inappropriately.  相似文献   
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