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231.
A eutectic mixture of local anesthetics (EMLA) in cream form has been used as a topical anesthetic to reduce the pain of procedures penetrating the skin. It is generally applied for 45 to 60 minutes before the painful procedure. The purpose of this study was to determine whether a 20-minute application of EMLA is useful in reducing the pain of routine peripheral intravenous cannulation in the emergency department (ED). A blinded, randomized, placebo-controlled, paired trial compared the pain of intravenous cannulation in both hands of study subjects: one hand was treated with 20-minute EMLA cream and the other hand was treated with 20-minute placebo cream. Forty subjects identified the more painful hand and scored pain measurements of each hand using a 10-cm visual analog scale. These data failed to demonstrate any significant benefit of EMLA compared with placebo. EMLA is not useful for intravenous cannulation when used for 20-minute application times. There may be more effective and less costly ways of reducing the pain of intravenous cannulation that patients would prefer. 相似文献
232.
AL Gropman RJ Packer HS Nicholson LG Vezina R Jakacki R Geyer JM Olson P Phillips M Needle EH Broxson G Reaman J Finlay 《Canadian Metallurgical Quarterly》1998,83(1):166-172
The c-Jun N terminal kinases (JNKs) are members of the mitogen activated protein kinases family, which have been shown to be preferentially activated either by cytokines or stress stimuli. In this study we identify a selective and potent antisense oligonucleotide to RhoA (ISIS 17131) and investigate its effect on JNK activation induced by IL-1beta and H2O2 in A549 cells. The RhoA antisense oligonucleotide was able to inhibit JNK activation when A549 cells were stimulated by H2O2, but did not have any effect on IL-1beta induced JNK activation. Consistent with the idea that the phosphatidylinositol 3-kinase (PI 3-kinase) activates the small G protein exchange factors, H2O2 activated the PI 3-kinase. Additionally, Wortmannin, a potent inhibitor of the PI 3-kinase and phospholipase A2 (PLA2), and AACOCF3, also a PLA2 inhibitor, were able to inhibit JNK activation induced by H2O2, but they had no effect on JNK activation when stimulated by IL-1beta. These results suggest that, in A549, IL-1beta and H2O2 induce JNK activation by two independent pathways. 相似文献
233.
234.
SCD is defined as unexpected death due to cardiac causes that occurs within 1 hour of acute symptoms. SCD can be reversed with the use of an ICD. These devices now can be implanted by catheter techniques, obviating thoracotomy. SCD is preventable. The incidence of SCD can be significantly reduced by addressing the fundamental pathophysiology of SCD, which primarily is CAD. Our combined and aggressive implementation of preventive regimens to reduce the risk of cardiac events will save lives. These measures include diet, weight reduction, smoking cessation, regular exercise, and therapeutic drugs. Amiodarone, although effective in preventing lethal ventricular arrhythmias, has not matched the long-term results of the ICD in the successful management of SCD. 相似文献
235.
CE Furlong WF Li LG Costa RJ Richter DM Shih AJ Lusis 《Canadian Metallurgical Quarterly》1998,19(4-5):645-650
Thin-layer chromatographic (TLC)-UV densitometric and gas-chromatographic-mass spectrometric detection (GC-MSD) methods were developed for simultaneous quantification of morphine and codeine in poppy capsules (Papaver somniferum). Morphine and codeine were isolated by extraction with chloroform: isopropanol (3:1, v/v) at pH = 8.5 and by solid-phase extraction on Snap-Cap cartridges at pH = 8.5. The TLC-UV densitometric quantification was performed by external standard method on silica gel plates using ethyl acetate: toluene: methanol: ammonia (68:17:10:5, v/v) as developing solvent and UV detection at 275 nm. For the GC-MSD analysis, the drugs were derivatized with acetic anhydride: pyridine (1:1, v/v) and separated on a 30 m HP5 capillary column. The quantification was performed using nalorphine as internal standard. 相似文献
236.
This case report describes the intraoperative improvement of somatosensory evoked potentials (SEPs) during the removal of a broached pedicle screw that had been placed in an unmonitored procedure 1 month earlier. Postoperatively, there was improved neurologic function and reversal of the neurologic deficit that had been caused by the first procedure. To our knowledge, this is the first report of a correlation of intraoperative SEP improvement with improved postoperative neurologic function after neurologic deficit because of nerve irritation or compression from a pedicle screw. Nerve damage occurs in about 15% of patients who undergo instrumentation after lumbar fusion. The potential utility of neurophysiologic methods during initial screw placement is suggested and supported, as proper use of such intraoperative tools may have prevented the need for the second procedure. 相似文献
237.
BACKGROUND: ACE inhibitors are valuable and effective drugs in the treatment of hypertension, heart failure, myocardial infarction and nephropathy. Angiotensin receptor antagonists, which have recently been introduced into clinical practice, have the potential to replace ACE inhibitor therapy in many patients. OBJECTIVE: To review the mechanisms of action, indications and side effects of ACE inhibitors and angiotensin receptor antagonists and to highlight similarities and differences between the two drug classes. DISCUSSION: Angiotensin receptor antagonists have the theoretical advantage of being more effective in blocking the effects of angiotensin II at angiotensin type I receptors. The potential disadvantage of not potentiating bradykinin may be compensated by the unopposed action of angiotensin II on vascular angiotensin type II receptors, which appear to mediate similar beneficial cardiovascular effects to bradykinin. Angiotensin II receptor antagonists have a lower incidence of adverse effects than ACE inhibitors as they do not produce cough and appear much less likely to produce angioedema. Although ACE inhibitors are the most commonly prescribed antihypertensive drug class in Australia, they are underused for the treatment of heart failure and left ventricular dysfunction following myocardial infarction. Angiotensin receptor antagonists may become alternative therapies to ACE inhibitors in these disorders. However, at present they are only indicated for the treatment of hypertension. 相似文献
238.
We recently identified a novel gene (PB39) (HGMW-approved symbol POV1) whose expression is up-regulated in human prostate cancer using tissue microdissection-based differential display analysis. In the present study we report the full-length sequencing of PB39 cDNA, genomic localization of the PB39 gene, and genomic sequence of the mouse homologue. The full-length human cDNA is 2317 nucleotides in length and contains an open reading frame of 559 amino acids which does not show homology with any reported human genes. The N-terminus contains charged amino acids and a helical loop pattern suggestive of an srp leader sequence for a secreted protein. Fluorescence in situ hybridization using PB39 cDNA as probe mapped the gene to chromosome 11p11.1-p11.2. Comparison of PB39 cDNA sequence with murine sequence available in the public database identified a region of previously sequenced mouse genomic DNA showing 67% amino acid sequence homology with human PB39. Based on alignment and comparison to the human cDNA the mouse genomic sequence suggests there are at least 14 exons in the mouse gene spread over approximately 100 kb of genomic sequence. Further analysis of PB39 expression in human tissues shows the presence of a unique splice variant mRNA that appears to be primarily associated with fetal tissues and tumors. Interestingly, the unique splice variant appears in prostatic intraepithelial neoplasia, a microscopic precursor lesion of prostate cancer. The current data support the hypothesis that PB39 plays a role in the development of human prostate cancer and will be useful in the analysis of the gene product in further human and murine studies. 相似文献
239.
PY Kwo VA Ramchandani S O'Connor D Amann LG Carr K Sandrasegaran KK Kopecky TK Li 《Canadian Metallurgical Quarterly》1998,115(6):1552-1557
BACKGROUND & AIMS: Alcoholic liver disease purportedly develops more readily in women than in men. Some studies have demonstrated faster rates of alcohol elimination in women. This study examined whether gender differences in alcohol metabolism are related to differences in liver volume and/or differences in lean body mass. METHODS: Ten men and 10 women had alcohol elimination rates determined by clamping of the breath alcohol concentration at 50 mg/dL by means of a constant rate of intravenous infusion of 6% ethanol. Liver volume was determined by computed tomography. RESULTS: Mean alcohol elimination rate and mean computed liver volume were not significantly different in men and women. Lean body mass was 42% greater in men than in women. Consequently, the calculated alcohol elimination rate and liver volume per kilogram of lean body mass were 33% and 38% higher in women than in men, respectively. When the alcohol elimination rate was calculated per unit liver volume, no gender-related difference was found. CONCLUSIONS: Women have greater clearance of ethanol per unit lean body mass, confirming previous oral alcohol administration studies. Women have approximately the same liver volume as men, explaining the equivalent alcohol elimination rates seen when men and women are compared on the basis of liver size. 相似文献
240.
Adipose-tissue lipolysis (assessed from glycerol release) and glucose uptake were examined in parametrial and mesenteric adipocytes prepared from control or hyperthyroid rats in relation to changes in insulin sensitivity. Basal rates of lipolysis did not differ significantly between adipose-tissue depots. Lipolysis was maximally stimulated by noradrenaline at 1 microM, half-maximal anti-lipolytic effects of insulin were observed at approximately 11 microU/ ml insulin, and half-maximal stimulation of glucose uptake was observed at approximately 16 microU/ml insulin in adipocytes from both depots. Wortmannin caused a dose-dependent inhibition of the anti-lipolytic effect of insulin (150 microU/ml) on noradrenaline-stimulated lipolysis. Half-maximal effects of wortmannin were observed at 20-40 nM. The p70S6K inhibitor rapamycin and the mitogen-activated protein kinase kinase inhibitor PD098059 had no effects on noradrenaline-stimulated lipolysis. Hyperthyroidism increased basal rates of lipolysis and the maximal response of lipolysis to noradrenaline stimulation (3.1-fold, P < 0.001 and 2.1-fold, P < 0.05 respectively) in parametrial adipocytes. Hyperthyroidism markedly blunted the sensitivity of noradrenaline-stimulated lipolysis to half-maximal suppression by insulin in both parametrial and mesenteric adipocyte depots, and noradrenaline-stimulated lipolysis at a maximal insulin concentration remained significantly higher in adipocytes prepared from hyperthyroid rats compared with controls. Hyperthyroidism had no effect on basal and little effect on insulin-stimulated glucose uptake. Tri-iodothyronine administered at a low dose selectively influenced the anti-lipolytic action of insulin in parametrial adipocytes, and led to significantly less marked elevation in plasma non-esterified fatty acid concentrations in vivo. The results demonstrate a selective effect of hyperthyroidism to impair insulin's anti-lipolytic action, and are consistent with the operation of different downstream signalling mechanisms for the effects of insulin on adipocyte glucose transport and lipolysis. 相似文献