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631.
Allelic association studies provide the most powerful method for locating genes of small effect contributing to complex diseases and traits. However, in outbred populations, allelic association is usually maintained only over distances of <=1 cM. Therefore, systematic searches over large regions are costly. Here we present a method involving DNA pooling that can be used as a rapid preliminary screen for allelic association with the most common class of polymorphic markers, single-sequence repeats. Patient and control samples are pooled separately, and markers are typed in the two pools. By use of primers with fluorescent 5' ends, PCR products can be analyzed on an automated sequencing apparatus. Allele image patterns (AIPs) produced for the two groups are overlaid and differences in pattern area between pools computed. From this, a DeltaAIP statistic is calculated from the difference in areas between the two AIPs expressed as a fraction of the total shared and nonshared area. AIPs of a range of different-sized pools were generated by computer simulation for markers with a range of allele sizes and frequencies. DeltaAIPs from pools and chi2 values for individual genotypings were compared, with both simulated and real data from microsatellite markers. The results demonstrated a high correlation between DeltaAIP and chi2 values. DeltaAIP analysis of real microsatellite data indicated the feasibility of using this method in systematic searches for allelic association and generated a small number of false positives but few false negatives. We conclude that DeltaAIP analysis of DNA pools can be used effectively and efficiently as a rapid screen for allelic association in case-control studies.  相似文献   
632.
Plasma antithrombin-III (AT-III), protein S, and protein C were measured during myocardial stunning (MS) and acute myocardial infarction (AMI). The effects of magnesium (Mg), diltiazem, and a Mac-1 inhibitor on their plasma levels were elucidated. Forty-nine open-chest swine underwent brief (8 min) or prolonged (50 min) coronary artery occlusion followed by reperfusion. During MS an increase in the plasma AT-III (from 98.5 +/- 3.38% to 138.1 +/- 3.6%) during the early occlusion phase, without any further changes was observed. The profile of total protein S was not changed during MS. Protein C increased at the end of occlusion (from 45.3 +/- 1.8% to 55.7 +/- 1.4%) reaching a peak (64.5 +/- 1.4%) at the beginning of reperfusion. When compared with controls, no significant differences were found in the antithrombotics profile during MS after pretreatment with Mac-1 inhibitor. For the AMI, the AT-III decreased during occlusion (from 98.5 +/- 3.4% to 61.0 +/- 3.6%). The protein S decreased during occlusion with the lowest level at 1 h of reperfusion (from 71.8 +/- 2.2% to 46.7 +/- 1.0%), followed by an increase during late reperfusion (59.2 +/- 1.5%). Contrarily, protein C increased during occlusion and early reperfusion (from 44.7 +/- 2.6% to 79.4 +/- 2.4%), but declined to 49.6 +/- 2.5% thereafter. In both Mg and diltiazem-treated swine, protein C was higher at the end of occlusion and during the entire reperfusion period compared with controls. Mg and diltiazem therapy was associated with the slight elevation of plasma AT-III. The patterns for protein S level during ischemia-reperfusion were similar with the controls. Protein S was higher at the end of occlusion and through the entire reperfusion in the NPC 15669-treated animals when compared with the controls. Mac-1 inhibition was associated with the elevated protein C during late reperfusion. Ability of Mg, diltiazem, and Mac-1 inhibitor to favorably modulate the plasma level of antithrombotics have direct clinical implications for the use of these agents in patients with acute coronary artery syndromes.  相似文献   
633.
634.
The pregnancies of black women are complicated by adverse outcomes such as prematurity and low birth weight at twice the rate of complications in pregnancies of white women. Although the cause of this racial disparity is unknown, it is most likely multifactorial. The disparity in outcomes has been found in many studies despite implementation of controls for the factors of age, socioeconomic status, and access to health care. We hypothesized that the increased incidence of adverse outcomes may be strongly affected by adequacy of prenatal care. We investigated the effects of comprehensive prenatal care delivered at the University of North Carolina-Chapel Hill Teenage Obstetric Clinic. The gestational age at the onset of prenatal care and the mean number of prenatal visits were the same for black and white teenagers. Among 183 teenagers we found no significant difference between black and white pregnancies for the outcomes of premature labor, premature delivery, fetal death, neonatal mortality, or hypertensive diseases. The mean gestational age at delivery was 38.3 weeks and 39.1 weeks for black and white women, respectively. The mean birth weight was 3126 gm and 3272 gm for black and white women, respectively. There was a trend (p < 0.09) toward more low birth weight infants in white women: 7% for black infants and 12% for white infants. We believe that comprehensive prenatal care significantly lessens the racial disparity in pregnancy outcomes between black and white adolescent women.  相似文献   
635.
The involvement of glycoprotein CD36 and fatty-acid-binding protein (FABP) in cellular growth, differentiation, lipid transport and metabolism led us to examine the possible biochemical and physiological relationship(s) between these two proteins. We investigated three aspects of this relationship. We first attempted to identify any physical complex formed between CD36 and FABP in bovine milk fat globule membranes. These membranes are the product of mammary gland secretory epithelial cells. The second aspect studied was the effect of synthetic peptide analogs to the C-terminus (amino acid residues 121-131) of bovine mammary gland FABP on cell proliferation, as a result of the interaction of these peptides with the ectodomain of CD36. Finally, mammary gland CD36 and FABP coexpression was defined at different stages of lactation and during involution. Immunoprecipitation, Western immunoblotting with anti-FABP and anti-CD36, Northern-blot analysis and a mammary epithelial cell proliferation assay demonstrated that: (a) bovine milk fat globule membranes contain the complex of CD36 and FABP, and that this complex is, most likely, formed as a result of FABP binding to the cytoplasmic segments of CD36; (b) synthetic analog of the C-terminus of FABP with the sequence Val-Thr-Cys, identical to the sequence found in the CD36-binding domain of thrombospondin, was a more potent inhibitor of bovine mammary gland epithelial cell proliferation than a synthetic peptide with the Val-Cys-Thr sequence; (c) the expression of FABP and CD36 is related to the state of mammary cell differentiation, since it reaches its maximum during lactation and declines during the involutionary period.  相似文献   
636.
In a randomized, cross-over study, we prospectively compared the efficacy and quality of two methods to achieve conscious sedation with propofol in 11 unpremedicated, anxious dental patients. Each patient underwent two dental procedures, one that was conducted under target-controlled infusion (TCI) by the anesthesiologist (ACS), and the other that used patient-controlled sedation (PCS). The initial target concentration in the ACS mode was 2.5 microg/mL, which was manipulated in both directions until the desired clinical end point was achieved. In the PCS mode, a 4-mg bolus of propofol (10 mg/mL) was delivered at each activation of the machine, infused over 7 s without a lockout interval. The anxious dental patients could induce and maintain conscious sedation with the PCS settings. The mean (range) venous blood propofol concentrations were not significantly different with either mode: ACS 1.8 (0.8-2.7) microg/mL and PCS 1.2 (0.2-2.5) microg/mL. The level of patient satisfaction, quality of sedation, and treatability were not different for either mode of sedation. The intensity of amnesia for intraoperative events was related to the blood concentrations achieved. In the ACS mode, one patient became unresponsive (sedation level 4) immediately after the start of sedation. No adverse cardiorespiratory effects resulted from either mode of propofol sedation. Five patients expressed a strong preference for PCS, and three would prefer ACS in the future. The results of the present study suggest that with these PCS settings, a satisfactory level of conscious sedation and a high level of patient satisfaction was achieved. Implications: In a randomized, cross-over study, the blood propofol concentrations necessary to achieve conscious sedation in anxious dental patients using a target-controlled infusion conducted by the anesthesiologist versus patient-controlled sedation were not different. With the patient-controlled sedation settings, a satisfactory level of conscious sedation and a high level of patient satisfaction were achieved.  相似文献   
637.
Diazepam (0.5 mg/kg) prevented reduction of motor activity of rats (both vertical and horizontal components) induced by vibrissae amputation. It is suggested that the observed decrease in motility is related to development of a pathologic reaction of anxiety. The method is recommended as a test for anxious behaviour in experiment.  相似文献   
638.
The purpose of this study was to determine the significance of transient ST-segment elevation during dobutamine infusions in patients with healed Q wave myocardial infarction. Twenty-seven patients with previous Q wave myocardial infarction were studied prospectively with dobutamine-thallium-201 single-photon emission computed tomography. The presence of ST-segment elevation in leads with Q waves was related to thallium reversibility at 4-hour redistribution imaging or after reinjection, to residual flow, as well as to wall motion abnormalities in the infarcted zone. ST-segment elevation in infarct-related leads was observed in 15 patients; 11 (73%) showed viability by thallium-201 in the infarcted zone. In patients without ST-segment elevation, viability was shown less frequently (33%, P < .05). Hypokinesis in infarcted segments was present in 60% of patients with ST-segment elevation and in 25% of patients without ST-segment elevation (.05 < P < .1). Finally, infarct-related artery was patent and/or collaterals were present in 10 patients with ST-segment elevation (67%) and in 4 patients without (33%, .05 < P < .1). In conclusion, ST-segment elevation during dobutamine infusion is a marker of residual viability in infarcted segments.  相似文献   
639.
Examined psychological adjustment in a college sample of older adolescents and young adults (n = 49) with histories of childhood asthma. A substantial number of subjects evidenced clinically significant levels of overall distress. In addition, greater perceived asthma uncertainty and increased stable attributions for negative events were significantly associated with poorer psychological adjustment after controlling for demographic and disease variables. Further analyses revealed a moderating influence of uncertainty on attribution-adjustment relationships. These findings provide initial support for a cognitive diathesis-stress view of adjustment in long-standing asthma. Results also support a growing body of evidence suggesting that the focus of efforts to enhance adjustment to asthma need to be expanded beyond childhood and early adolescence.  相似文献   
640.
Growth hormone replacement therapy of hypopituitary adult patients has demonstrated its usefulness during the last 12 years: it decreases excess body fat while raising lean mass and basal metabolic rate, it ameliorates the lipid profile of the patients and decreases their peripheral vascular resistance, it increases bone mineralization and ameliorates the quality of life of treated individuals. Based on these results, many other applications of growth hormone have been developed: treatment of old age, of simple and android obesities, of osteoporosis and extreme catabolic situations. The data collected have been of great pathophysiological interest, but do not lead for the present towards therapeutic indications.  相似文献   
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