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101.
The purpose of the present study was to demonstrate the reliability, validity, and responsiveness of the Activities of Daily Living Scale of the Knee Outcome Survey, a patient-reported measure of functional limitations imposed by pathological disorders and impairments of the knee during activities of daily living. The study comprised 397 patients; 213 were male, 156 were female, and the gender was not recorded for the remaining twenty-eight. The mean age of the patients was 33.3 years (range, twelve to seventy-six years). The patients were referred to physical therapy because of a wide variety of disorders of the knee, including ligamentous and meniscal injuries, patellofemoral pain, and osteoarthrosis. The Activities of Daily Living Scale was administered four times during an eight-week period: at the time of the initial evaluation and after one, four, and eight weeks of therapy. Concurrent measures of function included the Lysholm Knee Scale and several global measures of function. The subjects also provided an assessment of the change in function, with responses ranging from greatly worse to greatly better, at one, four, and eight weeks. The Activities of Daily Living Scale was administered to an additional sample of fifty-two patients (thirty-two male and twenty female patients with a mean age of 31.6 years [range, fourteen to sixty-six years]) before and after treatment within a single day to establish test-retest reliability. Factor analysis revealed two dominant factors: one that reflected a combination of symptoms and functional limitations and the other, only symptoms. The internal consistency of the Activities of Daily Living Scale was substantially higher than that of the Lysholm Knee Scale (coefficient alpha, 0.92 to 0.93 compared with 0.60 to 0.73), resulting in a smaller standard error of measurement for the former scale. Validity was demonstrated by moderately strong correlations with concurrent measures of function, including the Lysholm Knee Scale (r = 0.78 to 0.86) and the global assessment of function as measured on a scale ranging from 0 to 100 points (r = 0.66 to 0.75). Analysis of variance with repeated measures revealed significant improvements in the score on the Activities of Daily Living Scale during the eight weeks of physical therapy (F2,236 = 108.13; p < 0.0001); post hoc testing indicated that the change in the score at eight weeks was significantly greater than the change at four weeks and that the change at four weeks was significantly greater than that at one week (p < 0.0001 for both). As had been hypothesized, the patients in whom the knee had somewhat improved had a significantly smaller change in the score, both at four weeks (F1,189 = 33.50; p < 0.001) and at eight weeks (F1,156 = 22.48; p < 0.001), compared with those in whom the knee had greatly improved. The test-retest reliability coefficient (intraclass correlation coefficient[2,1]) was 0.97. These results suggest that the Activities of Daily Living Scale is a reliable, valid, and responsive instrument for the assessment of functional limitations that result from a wide variety of pathological disorders and impairments of the knee.  相似文献   
102.
It is unclear whether the intracardial immune reactivity after heart transplantation influences the peripheral immunological status (activation or nonresponsiveness) of the patient. Co-stimulation and activation-induced cell death (AICD) or apoptosis play an important role in determining the balance between lymphocyte reactivity and nonreactivity. Therefore, we studied the expression of co-stimulatory molecules and the process of apoptosis in biopsies of human heart allografts, using immunohistochemistry. Although a normal expression of co-stimulatory molecules on antigen-presenting cells was observed, the expression of their counter-structures on T cells was absent. This may be due to chronic T cell activation, which can lead to the induction of apoptosis via the Fas/Fas ligand pathway. In the infiltrates, a considerable percentage of the lymphocytes, but not the macrophages, were apoptotic. Apoptosis was confirmed by DNA fragmentation analysis. Increased numbers of Bax-expressing versus decreased numbers of Bcl2-expressing lymphocytes in comparison with normal lymphoid tissue confirmed a imbalance in favor of apoptosis. Apoptosis was biased towards CD4+ T cells (65.7% versus 26.6% in CD8+ T cells). Fas was expressed on most of the infiltrating cells. Fas ligand expression was also observed, not only on most of the T cells but also on all macrophages. Because macrophages were often detected in close contact with T cells, they may play a role in T cell regulation via the Fas/Fas ligand pathway. This study indicates that, during rejection, not only is tissue damage induced by infiltrating T cells, but also the infiltrating lymphocytes themselves are actively down-regulated (eg, AICD) by one another and by macrophages in the infiltrate. This regulatory process may affect the immunological status of the patient after heart transplantation.  相似文献   
103.
Transurethral electrovaporization of the prostate (TVP) is a new minimally invasive procedure for treatment of enlargement of prostate. Between April 1996 and September 1997, TVP was carried out in 109 cases with symptoms of lower urinary tract obstruction. A Stortz spike electrode and a Stortz vapor cutting electrode were used for vaporization electrodes. Efficacy parameters evaluated included International Prostate Symptom Score, peak uroflow and postvoid residual volume. By September 1997, 32 cases (spike electrode) and 33 cases (vapor cutting electrode) could be followed up and evaluated. They have shown both subjective and objective voiding improvement. The improvements in subjective symptom scores and objective voiding parameters were not significantly different between the two electrode groups. Early complications included urinary retention, intraoperative burn, stress incontinence, blood transfusion and postoperative hemorrhage. Late complications included urethral stricture, bladder neck contracture and bladder stone. TVP was found to have several advantages, particularly minimal bleeding and the low incidence of postoperative morbidity. The technique is simple and symptoms improve at an early stage following surgery. This study demonstrates that TVP is a safe and effective modality for treatment of BPH. However, long-term studies with larger numbers of patients are needed.  相似文献   
104.
105.
BACKGROUND/AIMS: The number of perisinusoidal myofibroblasts has been shown to be increased in hepatocellular carcinoma, as compared to cirrhosis. This increase might suggest a cooperative relationship between tumour cells and myofibroblasts. To assess this relationship, we undertook: (a) an immunohistochemical study to confirm the existence of an increased number of perisinusoidal myofibroblasts in human hepatocellular carcinoma, as compared to cirrhosis with or without liver cell dysplasia, (b) an in vitro study testing the role of normal or tumoral human hepatocytes in myofibroblast proliferation. METHODS: Forty explanted cirrhotic livers, including 14 with hepatocellular carcinoma and 24 with liver cell dysplasia, were studied. Myofibroblasts were detected by immunohistochemistry using an antibody directed against alpha-smooth muscle actin. Hepatic myofibroblasts in culture were obtained by outgrowth from human liver explants. RESULTS: There was a progressive increase in the number of perisinusoidal myofibroblasts, from cirrhotic nodules without dysplasia to liver cell dysplasia and hepatocellular carcinoma. Conditioned medium from isolated normal human hepatocytes had only minor mitogenic effects on myofibroblasts, as assessed by measuring DNA synthesis and cell growth. In contrast, conditioned medium from a human hepatoma cell line (HepG2 cells) markedly stimulated the proliferation of human myofibroblasts. This mitogenic activity was stored in HepG2 cells and secreted in the extracellular medium rather than being simply released following cell lysis. CONCLUSIONS: These results suggest that the increased number of myofibroblasts in hepatocellular carcinoma might be due to a paracrine mechanism involving soluble mitogenic factor(s) secreted by tumour cells.  相似文献   
106.
BACKGROUND: Left ventricular hypertrophy (LVH) represents an important intermediate end-point for, for example, the progression to heart failure. The persistence or progression of LVH despite antihypertensive therapy probably reflects the persistence or activation of mechanisms that negatively affect the cardiovascular system and, consequently, long-term outcome. EFFECT OF MODERN ANTIHYPERTENSIVE AGENTS: Long-term treatment with rapid-onset (and usually short-acting) dihydropyridine calcium antagonists is significantly less effective than angiotensin converting enzyme (ACE) inhibition in reducing left ventricular mass (LVM) in hypertensive patients. Both intermittent, and probably only partial, blood pressure control and an increase in sympathetic activity resulting from rapid decreases in blood pressure following dosing with such calcium antagonists may contribute to this relative ineffectiveness. In contrast, more recent studies have demonstrated that the longer acting dihydropyridines can reduce LVM as effectively as ACE inhibitors. DISTINCTIONS AMONG DIHYDROPYRIDINE CALCIUM ANTAGONISTS: Among the 1,4-dihydropyridines, drugs such as amlodipine and nifedipine in the gastrointestinal therapeutic system (GITS) maintain good blood pressure control over the full 24-h dosing period and do not cause dose-related increases in sympathetic activity. In contrast, extended-release felodipine has been shown to provide only intermittent blood pressure control, still leading to sympathetic activation. Notably, during short periods of noncompliance, blood pressure control is maintained with intrinsically long-acting agents such as amlodipine but not with slow-release formulations of short-acting agents such as nifedipine GITS. CONCLUSIONS: It is possible that the rate of onset and duration of action of various dihydropyridines may be pivotal factors in determining their effects on cardiovascular outcomes. Thus, the least beneficial dihydropyridines may be rapid-onset, short-acting agents, such as nifedipine capsules, and the most beneficial may be the slow-onset, long-acting agents such as amlodipine.  相似文献   
107.
BACKGROUND/AIMS: Treatment with ursodeoxycholic acid has been shown to decrease the rate of disease progression in patients with primary biliary cirrhosis, although the effect is modest. Since primary biliary cirrhosis has many features of an autoimmune disorder, immunosuppressives added to ursodeoxycholic acid may be of value in the treatment of primary biliary cirrhosis. METHODS: A 1-year randomized, double-blind, placebo-controlled trial was carried out in 50 patients with primary biliary cirrhosis, who had already been treated with ursodeoxycholic acid for at least 1 year, but had not achieved complete disease remission. Patients were randomized to additional prednisone (30 mg per day initially, tapered to 10 mg daily after 8 weeks) and azathioprine (50 mg daily) or placebo. A subgroup of patients received cyclical etidronate and calcium. The principal aim of the study was to assess the short-term benefits and risks of the combined bile acid and low-dose immunosuppressive regimen. Primary endpoints were effects on symptoms, liver biochemistry, liver histology, bone mass and the occurrence of adverse events. RESULTS: Pruritus (p=0.02), alkaline phosphatase, aspartate aminotransferase, IgM and procollagen-III-propeptide improved significantly (all p<0.002) in the combined treatment group as compared to the placebo group. Histological scores for disease activity and disease stage decreased significantly within the combination treatment group (p<0.001). CONCLUSIONS: In patients with primary biliary cirrhosis receiving ursodeoxycholic acid, there is an additional beneficial effect of 1-year treatment with prednisone and azathioprine on symptoms and biochemical, fibrogenetic and histological parameters. These results strongly encourage the evaluation of this triple treatment regimen in long-term controlled trials of adequate size to document its effect on clinical events.  相似文献   
108.
OBJECTIVE: To reveal the relationship between fasting and 2-h postload plasma glucose and to examine the appropriate fasting glucose cutoff as the primary screening test for diabetes. RESEARCH DESIGN AND METHODS: We recruited 5,303 subjects from preventive services of the National Cheng Kung University Hospital. Exclusion criteria were age <20 years, pregnancy, known diabetes, and a history of recent surgery, trauma, or illness. All subjects received the 75-g oral glucose tolerance test. The relationship between fasting and 2-h glucose was examined. Sensitivities, specificities, efficiency, and predictive values were assessed at different cutoffs of fasting glucose for prediction of diabetes. RESULTS: The best fit model for the relationship between fasting and 2-h glucose was fasting glucose = 4.914-0.060 x (2-h glucose) + 0.0144 x (2-h glucose)2. From this model, the fasting glucose was 6.0 mmol/l when 2-h glucose was 11.1 mmol/l. A fasting glucose with 6.25 mmol/l gave the same diabetes prevalence as the World Health Organization 2-h glucose criterion. When 7.8 mmol/l was the fasting glucose cutoff, the sensitivity was 28.5%. Lowering the cutoff from 7.8 to 7.0 mmol/l increased the sensitivity by 11.2% and slightly reduced the specificity and positive predictive value. If the cutoffs were 6.25 and 6.0 mmol/l, the sensitivity increased and the specificity and the positive predictive value decreased accordingly. CONCLUSIONS: Our results suggest that fasting glucose as a screening criterion for diabetes could be revised downward to 7.0 mmol/l, because the slight reduction of positive predictive value was more than balanced by an apparent increase of sensitivity and insignificant change of specificity.  相似文献   
109.
110.
The Precision Quantum-in-dium (Q.I.D.) Glucometer was used to determine the glucose concentrations of 38 human blood samples. The same samples were also run on the OPERA Chemistry Autoanalyzer 2010 system. More than 44% of the glucometer reports had a difference of greater than 15% from the respective autoanalyzer reports. The calibration of the glucometer could be the source of the error and an improvement is recommended.  相似文献   
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