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991.
Mutations in the human patched gene have recently been detected in patients with naevoid basal cell carcinoma syndrome. We have characterised a further 5 novel germ line mutations in patients presenting with multiple odontogenic keratocysts. Four mutations cause premature stop codons and one mutation results in an amino-acid substitution towards the carboxyl terminus of the predicted patched protein. No obvious genotype-phenotype correlations could be interpreted, consistent with previous studies.  相似文献   
992.
BACKGROUND: The present study examined the power of individual Mini-Mental State Examination (MMSE) items in predicting incidence of Alzheimer's disease (AD). In addition, 3-year longitudinal changes in MMSE items were contrasted between incident AD and nondemented persons. METHODS: A population-based group of very old adults, 75-95 years of age, were followed longitudinally. Of the original 327 participants, 32 were diagnosed with probable or possible AD after a 3-year follow-up interval and 189 remained nondemented. Cognitive performance was indexed by the individual item scores from the MMSE. These sample from multiple domains of cognitive functioning, including visuospatial skill, recent memory, orientation to time and place, language, and the ability to sustain attention. RESULTS: Items dealing with delayed episodic memory and orientation to time were significant predictors of AD incidence, independent of age, gender, and years of education, as determined by logistic regression analyses. Longitudinally, changes in performance were largest among individuals diagnosed as incident AD, although the magnitude of change across items was highly variable. In particular, decline was relatively small for the delayed memory item, whereas most other measures showed dramatic decline in performance among individuals with incident AD. CONCLUSIONS: Individual MMSE items, especially those with some type of episodic memory referent, were the best predictors of incident cases of AD. Moreover, MMSE items displayed differential rates of changes, particularly for the incident AD participants.  相似文献   
993.
This study was conducted to determine how phaco-emulsification combined with trabeculectomy influenced intraocular pressure and need for glaucoma medication postoperatively. A retrospective analysis was undertaken of results relating to 243 eyes of 195 patients who had undergone phaco-emulsification combined with trabeculectomy. Pre-operative intraocular pressure decreased from a mean of 22.0 mmHg to 12.5 mmHg one week postoperatively with an average change of 9.5 mmHg. One month postoperatively, 70% of patients were without glaucoma medication. Visual acuity had improved in 80% of eyes. Phaco-emulsification combined with trabeculectomy resulted in excellent glaucoma control, good visual recovery and a need for fewer glaucoma drugs.  相似文献   
994.
The actions of the endogenous ORL1-receptor ligand nociceptin on the membrane properties and synaptic currents in rat periaqueductal gray (PAG) neurons were examined by the use of whole-cell patch-clamp recording in brain slices. Nociceptin produced an outward current in all neurons tested, with an EC50 of 39 +/- 7 nM. The outward current was unaffected by naloxone. Outward currents reversed polarity at -110 +/- 3 mV in 2.5 mM extracellular potassium, and the reversal potential increased when the extracellular potassium concentration was raised (slope = 66.3 mV/log[K+]o mM). Thus, the nociceptin-induced outward current was attributable to an increased K+ conductance. Nociceptin inhibited evoked fast GABAergic (IP-SCs) and glutamatergic (EPSCs) postsynaptic currents and increased paired-pulse facilitation in a subpopulation of PAG neurons. Nociceptin inhibited evoked IPSCs and EPSCs in approximately 50% of neurons throughout the PAG, except in the ventrolateral PAG, where nociceptin inhibited evoked IPSCs in most neurons. Nociceptin decreased the frequency of spontaneous miniature postsynaptic currents (mIPSCs and mEPSCs) in a subpopulation of PAG neurons but had no effect on their amplitude distributions. Thus, nociceptin had a presynaptic inhibitory effect on transmitter release. These findings suggest that nociceptin, via its pre- and postsynaptic actions, has the potential to modulate the analgesic, behavioral, and autonomic functions of the PAG.  相似文献   
995.
Four experiments examined the effects of excitotoxic, axon-sparing lesions of the medial prefrontal cortex or anterior cingulate cortex in rats on responding under different schedules of intravenous cocaine self-administration and on the locomotor stimulant effects of cocaine. Experiment 1 tested the acquisition and maintenance of cocaine self-administration under a fixed ratio schedule. Rats with medial prefrontal cortex lesions showed facilitated acquisition and enhanced responding for low doses of the drug when lesions were induced before self-administration behaviour was established. Lesions of the anterior cingulate cortex did not affect cocaine self-administration. In experiment 2, rats were trained to respond under a second-order schedule of cocaine reinforcement, where responding during the fixed interval was reinforced by presentation of a cocaine-associated visual stimulus under fixed-ratio contingencies. In control rats, these schedule conditions were found to maintain high rates of responding and a scalloped pattern of responding over time. Omission of conditioned stimulus presentation during the fixed interval significantly disrupted response patterns, confirming that the stimulus served to maintain responding during the fixed interval. By contrast, rats with medial prefrontal cortex lesions showed higher rates and disrupted patterns of responding that were unchanged by stimulus omission. Rats with lesions of the anterior cingulate cortex responded at high rates throughout the fixed interval under all test conditions, indicating that the cocaine-associated stimulus did not serve to maintain temporal patterns of responding in these rats. Experiment 3 demonstrated the lack of effect of either lesion on the acquisition of responding for a non-drug reinforcer, sucrose. In experiment 4, measures of spontaneous and cocaine-induced locomotor activity revealed that rats in both lesion groups were significantly more active than controls regardless of test conditions. These data indicate that facilitated acquisition of cocaine self-administration and disrupted response patterns under second-order schedule contingencies may result from deficits in behavioural inhibition induced by medial prefrontal cortical lesions that contrast with deficits following damage to other limbic cortical regions, such as the basolateral amygdala or anterior cingulate cortex.  相似文献   
996.
The time-dependent actions following pretreatment or delayed administration of the nitric oxide (NO) synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME) on colonic inflammation and inducible NO synthase activity following the intrarectal administration of trinitrobenzene sulphonic acid (TNBS) were evaluated in the rat. Intracolonic instillation of TNBS (30 mg in 0.25 ml of 50% ethanol) led to macroscopic injury, an increase of mucosal myeloperoxidase activity and the expression of the Ca2+-independent inducible NO synthase over 8 days. The inflammatory response following TNBS reached maximum levels between 12 and 72 h and then it declined until 14 days. Oral administration of L-NAME (25 mg/kg per 24 h in the drinking water) 2 days before TNBS augmented macroscopic damage and increased colonic inducible NO synthase activity 6, 12, 24 and 72 h after TNBS administration. In contrast, when L-NAME was administered 6 h after TNBS instillation, at time of expression of inducible NO synthase, the macroscopic lesions were reduced, as well as the enhanced inducible NO synthase activity, determined, over 72 h. Delayed (6 h after TNBS) administration of L-NAME also attenuated the colonic myeloperoxidase activity provoked by TNBS, after 24 h. This activity was not affected by pretreatment (2 days before TNBS) with L-NAME. These findings indicate that the timing of administration of non-selective NO synthase inhibitors such as L-NAME, in models of colitis is critical to the eventual outcome. Thus, pretreatment with L-NAME, which will inhibit constitutive NO synthase, exacerbates the subsequent damage following challenge. In contrast, delayed administration of L-NAME at the time of inducible NO synthase expression, has a beneficial action on the colonic injury and inflammation.  相似文献   
997.
Reviews the book, Understanding psychological research: An introduction to methods by Richard St. Jean (2001). Richard St. Jean's book has the stated goal to be a brief text that presents essential concepts in a concise but interesting format. In this the author succeeds admirably. The nine short chapters and three appendices present the basic content that any method course needs to cover. The chapters are centred around lively research examples, often from the author's own work. Each chapter is followed by a brief summary and a glossary of key terms. The examples are used to introduce the methodological question and to illustrate various solutions. If the book suffers from a drawback, it is that it is too good at what it wants to be: an easily accessible, succinct introduction. The author visibly aims to make the issues as clear and understandable as possible, even if this implies glossing over details and leaving out more difficult aspects. The book does not want to be, nor is it, a manual for people who actual want to do research. In sum, this book will be most useful for those who teach introductory methods courses aimed at students who want to "consume" research rather than pursue it themselves. For these students, the book will be a valuable resource to better understand pertinent issues and to be alert towards methodological problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Urinary incontinence is one of the most common problems afflicting older adults and a major contributor to healthcare costs for homebound older individuals. The authors conducted a randomized controlled clinical study examining the effectiveness of biofeedback-assisted pelvic floor muscle training and prompted voiding in treating urinary incontinence in homebound older adults. This article briefly describes the assessment and treatment protocols utilized during this study and describes their subsequent application to clinical practice within a large urban home health agency.  相似文献   
999.
1000.
PURPOSE: To establish the maximum-tolerated dose (MTD) and define the toxicities of a single-dose infusion of PNU-214565, a recombinant Escherichia coli-derived fusion protein of Staphylococcal enterotoxin A (SEA) and the Fab-fragment of the C242 monoclonal antibody in patients with advanced colorectal and pancreatic carcinomas. To investigate the capability of PNU-214565 to induce a superantigen (SAg) response resulting in cytokine production and tumor regression. PATIENTS AND METHODS: Twenty-one patients (age range, 39 to 76 years; median, 64; 12 men, nine women; 18 colorectal, three pancreatic cancers) were treated with a single 3-hour infusion of PNU-214565, with doses ranging from 0.01 to 1.5 ng/kg. All patients had prior chemotherapy and a good performance status Eastern Cooperative Oncology Group [ECOG] performance status [PS] = 0 [n = 10]; PS = 1 [n = 11]), 10 had prior radiation, and 18 had prior surgery. RESULTS: Fever and hypotension were the most common toxicities. Fever of any grade occurred in 16 of 21 patients (76%): four of 21 (19%) with grade 2 and two of 21 (9.5%) with grade 3. Hypotension of any grade occurred in 13 of 21 (62%): four of 21 with grade 2 and one of 21 (5%) with grade 3. Interleukin-2 (IL-2) and tumor necrosis factor alpha (TNF alpha) induction correlated with toxicity. In the two patients with grade 3 fever, peak IL-2 and TNF alpha levels were 2.9 IU/mL and 165 pg/mL, and 8.3 IU/mL and 245 pg/mL, respectively. Transient, > or = 50% decreases in circulating monocytes were observed in 17 of 21 patients as early as 0.5 hours (median time, 2 hours) from the start of infusion. Decreases (mean 33%) in circulating lymphocytes were observed in seven of 21 patients. All three patients with grade 3 toxicity were treated at the 0.5-ng/kg dose. The significance of baseline anti-SEA, human antimouse antibody (HAMA), CA242-soluble antigen levels, and T-cell receptor variable beta region (TCR V beta) subsets and histocompatibility leukocyte antigen-DR (HLA-DR) genotypes was assessed as possible predictors of toxicity. All toxicities were transient and easily managed. No grade 3 toxicity occurred at the higher dose levels. CONCLUSION: PNU-214565, a SAg-based tumor targeted therapy, is safe when given as a single 3-hour infusion at doses up to 1.5 ng/kg. The MTD for a single dose was not determined. The safety of a repeated dose schedule is currently under investigation, beginning with doses determined to be safe in this trial.  相似文献   
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