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871.
OBJECTIVE: The toxicity of bilirubin (BP) on the brain presents unknown aspects. Therefore, the treatment for neonatal hyperbilirubinemia is controversial. The aim of this study was to establish if moderate levels of BP produce toxicity in brain nuclei that regulate the biological rhythms (BR) of healthy full-term newborns. PATIENTS AND METHODS: We studied 17 jaundiced (BP 12.8-18.1 mg/dl) and 36 non jaundiced newborns. Heart and respiratory rate, temperature and systolic blood pressure were recorded during 24 hours at 30 minute intervals. Cosinor analysis was used to calculate the incidence of BR. The Fisher exact test was carried out to compare both groups and the relative risks to determine the association between hyperbilirubinemia and the absence of BR. RESULTS: Differences in the BR parameters did not reach statistical significance. Differences in heart rate 12-h BR (p = 0.071) and systolic blood pressure 8-h BR (p = 0.076) approached a statistical significance. The 95% confidence intervals of the relative risks were all close to 1 and the lower limits in respiratory rate (0.40) and systolic blood pressure (0.35) 24-h BR indicate a negative association. CONCLUSIONS: The aim was to verify the relationship between moderate neonatal hyperbilirubinemia and the decrease in the incidence of BR. The results do not show the sought after relationship and provide evidence against neurotoxicity from moderate levels of bilirubin. The limited evidence for developing long term mental alterations permits us to make an optimistic prognosis for full-term newborns with moderately elevated levels of bilirubin. 相似文献
872.
C Cardillo CM Kilcoyne AA Quyyumi RO Cannon JA Panza 《Canadian Metallurgical Quarterly》1997,80(8):1070-1074
Vascular production of nitric oxide (NO) plays an important role in a variety of physiologic processes. This study examines the contribution of NO to the vasodilator response to mental stress. The effects of mental arithmetic testing on forearm vascular dynamics were analyzed in 15 normal subjects (9 men; age 45 +/- 12 years) during intraarterial infusion of either saline or N(G)-monomethyl-L-arginine (L-NMMA; 4 micromol/min for 15 minutes), an inhibitor of NO synthesis. The effect of L-NMMA on endothelium-independent vasodilation induced by intraarterial infusion of sodium nitroprusside was also studied in 11 of the 15 subjects. Forearm blood flow was measured by plethysmography. Mental stress increased forearm blood flow from 2.35 +/- 0.84 to 5.06 +/- 2.66 ml/min/dl (115%) during saline and from 1.72 +/- 0.59 to 2.81 +/- 0.99 ml/min/dl (63%) during L-NMMA infusion. The vasodilator effect of mental stress was significantly lower during L-NMMA infusion than during saline (1.1 +/- 0.65 vs 2.71 +/- 2.15 ml/min/dl; p = 0.01). L-NMMA administration did not significantly change mean arterial pressure and heart rate responses to mental stress. In contrast, the vasodilator effect of sodium nitroprusside (1.6 microg/min) was similar during infusion of L-NMMA and during saline (3.75 +/- 1.55 vs 2.85 +/- 1.38 ml/min/dl; p = 0.16). These findings indicate that local release of NO is involved in the forearm vasodilator response to mental stress. 相似文献
873.
JM Laurienzo RO Cannon AA Quyyumi V Dilsizian JA Panza 《Canadian Metallurgical Quarterly》1997,80(11):1402-1407
The detection of coronary artery disease (CAD) by noninvasive methods has been hindered in women by the high rate of false-positive results. To determine the feasibility and accuracy of transesophageal dobutamine stress echocardiography for identification of CAD in women, we studied 84 patients (age 51 +/- 11 years) who underwent symptom-limited exercise treadmill testing, exercise thallium-201 scintigraphy, and coronary angiography for evaluation of anginal chest pain. Of the 84 patients, 62 had normal coronary arteries or nonsignificant coronary lesions, and 22 had significant stenosis of > or = 1 major coronary artery. During treadmill exercise, repolarization changes were observed in 16 of 21 patients with CAD and in 19 of 60 patients with normal coronary arteries. With thallium scintigraphy, a reversible defect was observed in 19 of 22 patients with CAD and in 12 of 60 patients with normal coronary arteries. Regional wall motion abnormalities during dobutamine infusion developed in 18 of 22 patients with CAD and in none of the 62 patients with normal coronary arteries. All 3 tests had similar sensitivity for detection of CAD (76% for exercise treadmill test, 86% for thallium scintigraphy, and 82% for transesophageal dobutamine stress echocardiography). However, transesophageal dobutamine stress echocardiography had significantly higher specificity than the other 2 tests (100% vs 68% for exercise treadmill test and 80% for thallium scintigraphy; p = 0.0001). Thus, transesophageal dobutamine stress echocardiography is accurate for evaluation of CAD among women presenting with chest pain; its use should be considered when more conventional tests are equivocal or technically suboptimal. 相似文献
874.
875.
SA Bahabri WM Suwairi RM Laxer A Polinkovsky AA Dalaan ML Warman 《Canadian Metallurgical Quarterly》1998,41(4):730-735
OBJECTIVE: To delineate the clinical features in patients with the autosomal recessive camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) and to determine the location of the involved gene. METHODS: Eight affected individuals (ages 2-15 years) with CACP from 4 consanguineous kindreds were clinically evaluated. Four patients are newly described and 4 have been reported previously. Findings were compared with those in 21 other previously reported cases. DNA obtained from the 8 affected patients and their available siblings and parents was used in a genome-wide search for linkage. RESULTS: Congenital camptodactyly and childhood-onset noninflammatory arthropathy were present in all affected patients. Seven patients developed bilateral coxa vara deformity, and 1 developed coxa magna with cystic erosions. Two of the patients also had symptoms or signs of pericarditis. A genome-wide search for linkage identified homozygosity for a series of genetic markers on human chromosome 1q in all affected patients. The marker D1S191 yielded a maximum logarithm of the odds ratio (LOD score) of 3.3 at theta = 0. The CACP gene lies within a 1.9-cM candidate interval defined by the markers D1S2107 and D1S222. CONCLUSION: The principal features of the CACP syndrome are congenital or early-onset camptodactyly and childhood-onset noninflammatory arthropathy. Coxa vara deformity or other dysplasia associated with progressive hip disease may develop over time. Clinical pericarditis may also occur. A locus responsible for causing CACP syndrome is assigned to a 1.9-cM interval on human chromosome 1q25-31 by homozygosity mapping. This now facilitates the identification of the responsible gene and permits testing for locus homogeneity in other CACP kindreds. 相似文献
876.
AA Petersen F Sellebjerg J Frederiksen J Olesen GL Vejlsgaard 《Canadian Metallurgical Quarterly》1998,88(1-2):120-127
We measured sICAM-1 in paired samples of serum and cerebrospinal fluid (CSF) from patients with an attack of multiple sclerosis (MS) (n = 50) and patients with acute monosymptomatic optic neuritis (ON) as a possible first attack of MS were also included (n = 25). Based on calculations of extended indices we found evidence of intrathecal synthesis of sICAM-1 both in patients with clinically definite MS and in patients with idiopathic ON compared to neurological control subjects. The amount of intrathecally synthesized sICAM-1 correlated significantly to the CSF leukocyte count and to the concentration of myelin basic protein in the CSF. The serum concentrations of sICAM-1 were not increased in patients with demyelinating disease compared to the neurological control subjects. 相似文献
877.
The results of an investigation of the hippocampal theta rhythm of rats in the paradoxical phase of sleep and during orienting behavior by the method of estimation of attractor dimension are presented in this article. It has been demonstrated that the hippocampal theta rhythm consists of a regular constituent and an irregular constituent of high dimension, the interrelationship of which varies within wide limits depending upon the state of the animal. Frequency components of the regular and irregular constituents were identified. The mechanisms of their formation are considered and some hypotheses regarding their biological nature are proposed. 相似文献
878.
879.
P Magnani PV Cherian GW Gould DA Greene AA Sima FC Brosius 《Canadian Metallurgical Quarterly》1996,45(12):1466-1473
Peripheral nerve depends on glucose oxidation to energize the repolarization of excitable axonal membranes following impulse conduction, hence requiring high-energy demands by the axon at the node of Ranvier. To enter the axon at this site, glucose must be transported from the endoneurial space across Schwann cell plasma membranes and the axolemma. Such transport is likely to be mediated by facilitative glucose transporters. Although immunohistochemical studies of peripheral nerves have detected high levels of the transporter GLUT1 in endoneurial capillaries and perineurium, localization of glucose transporters to Schwann cells or peripheral axons in vivo has not been documented. In this study, we demonstrate that the GLUT1 transporter is expressed in the plasma membrane and cytoplasm of myelinating Schwann cells around the nodes of Ranvier and in the Schmidt-Lanterman incisures, making them potential sites of transcellular glucose transport. No GLUT1 was detected in axonal membranes. GLUT3 mRNA was expressed only at low levels, but GLUT3 polypeptide was barely detected by immunocytochemistry or immunoblotting in peripheral nerve from young adult rats. However, in 13-month-old rats, GLUT3 polypeptide was present in myelinated fibers, endoneurial capillaries, and perineurium. In myelinated fibers, GLUT3 appeared to be preferentially expressed in the paranodal regions of Schwann cells and nodal axons, but was also present in the internodal aspects of these structures. The results of the present study suggest that both Schwann cell GLUT1 and axonal and Schwann cell GLUT3 are involved in the transport of glucose into the metabolically active regions of peripheral axons. 相似文献
880.
AI Sarela AA Mavanur A Bhaskar ZF Soonawala G Devnani HK Shah AB Samsi 《Canadian Metallurgical Quarterly》1996,42(3):78-80
A lumbar hernia which had developed following blunt abdominopelvic trauma is described here. The successful surgical correction is reported. 相似文献