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51.
Thoracic epidural analgesia in aortocoronary bypass surgery II: effects on the endocrine metabolic response 总被引:3,自引:0,他引:3
R. STENSETH L. BJELLA E. M. BERG O. CHRISTENSEN O. W. LEVANG S. E. GISVOLD 《Acta anaesthesiologica Scandinavica》1994,38(8):834-839
Thoracic epidural analgesia (TEA) may offer haemodynamic benefits for patients with coronary heart disease going through major surgery. This may – in part – be secondary to an effect on the endocrine and metabolic response to surgery. We therefore investigated the effect of TEA on the endocrine metabolic response to aortocoronary bypass surgery (ACBS).
Thirty male patients (age < 65 years, ejection fraction > 0.5) were randomized into 3 groups; the HF group receiving a high dose fentanyl (55 μg–kg-1 ) anaesthesia, the HF + TEA group with the same fentanyl dose + TEA with 10 ml bupivacain 5 mg ml-1 , followed by 4 ml every hour, and the LF + TEA group receiving fentanyl 15 μg kg-1 + TEA. Adrenalin, noradrenalin, systemic vascular resistance (SVR), glucose, Cortisol, lactate and free fatty acids were followed during the operation and for 20 h postoperatively.
A significant increase in adrenalin, noradrenalin and SVR was found in the HF group whereas this increase was blocked in both epidural groups. An increase in glucose and Cortisol was noticed in all groups, but the increase was delayed in the epidural groups.
Our results suggest that a more effective blockade of the stress response during ACBS is obtained when TEA is added to general anaesthesia than with high dose fentanyl anaesthesia alone. 相似文献
Thirty male patients (age < 65 years, ejection fraction > 0.5) were randomized into 3 groups; the HF group receiving a high dose fentanyl (55 μg–kg
A significant increase in adrenalin, noradrenalin and SVR was found in the HF group whereas this increase was blocked in both epidural groups. An increase in glucose and Cortisol was noticed in all groups, but the increase was delayed in the epidural groups.
Our results suggest that a more effective blockade of the stress response during ACBS is obtained when TEA is added to general anaesthesia than with high dose fentanyl anaesthesia alone. 相似文献
52.
In the cortex only a few of the available NMDA receptors must be activated to evoke maximal release of adenosine. In fact, maximal adenosine release occurs at 30 μM NMDA, a concentration at which noradrenaline release is only 20% maximal. NMDA-evoked noradrenaline release appears to require the generation of propagated action potentials, while adenosine release does not. Noncompetitive block of NMDA-evoked release of adenosine, but not noradrenaline, can be overcome by increasing NMDA concentrations. The above findings are consistent with the possibility that there are spare receptors for NMDA-evoked adenosine release, but not for nor-adrenaline release. These spare receptors are not due to elevated levels of glycine in the vicinity of those NMDA receptors mediating adenosine release. Functionally, it appears that low level NMDA receptor activation provides a purinergic inhibitory threshold against higher level NMDA receptor mediated processes. This could provide inhibitory tone and selectivity for critical functions, such as learning, memory, and synaptic plasticity in the cortex. © 1993 Wiley-Liss, Inc. 相似文献
53.
反相高压液相色谱法测定血清中部分氨基酸 总被引:8,自引:0,他引:8
目的:建立测定血清中精氨酸含量的方法。方法:反相高压液相色谱法。HypersilBDS柱,邻苯二甲醛柱前衍生化、萤光检测法检测。结果:精氨酸线性范围为383μmol/L~4789μmol/L,8种氨基酸的最低检测限为2μmol/L,日内变异系数为275%~1193%,日间变异系数为705%~1239%,5种氨基酸的回收率为9633%~10078%。正常人血清精氨酸水平为9277±1790μmol/L,糖尿病患者血清精氨酸水平则为7861±3303μmol/L(P>005)。结论:本方法简单易行,方法学实验结果满意,适用于临床测定相关氨基酸的需要 相似文献
54.
LAURENT MICLO EMMANUEL PERRIN ALAIN DRIOU MICHEL MELLET GUY LINDEN 《Chemical biology & drug design》1995,46(2):186-192
A method for the simultaneous determination of the ratios of the three aromatic amino-acid residues in peptides was set up in acidic conditions. Binary and ternary mixtures of these amino acids were prepared, and first- and second-derivative spectra then calculated from their 0.1 nm resolution spectra between 240 and 320 nm. Certain spectral bands were chosen to differentiate tyrosine from tryptophan on the first-derivative spectra, and phenylalanine from tyrosine and tryptophan on the second-derivative spectra. Variation of the amplitude of the chosen bands was shown to be a linear function of the ratio of the aromatic amino acids in the mixture. This technique was validated with peptides whose sequence was known. The difference between theoretical and experimentally determined ratios was lower than 10%. Since the results are obtained as ratios, neither the concentration nor the nature of the peptide has to be known. The feasibility of application using a photodiode array detector with high resolution in reversed-phase high-performance liquid chromatography is discussed. © Munksgaard 1995. 相似文献
55.
James T. Winslow Thomas R. Insel 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):745-757
1. Rat pups emit ultrasonic calls during brief episodes of social separation. These calls have been variously described as “distress” calls and may be related to the separation cries expressed by the young of many mammalian species.
2. Ultrasonic call of rat pups are modulated by environmental stimuli such as ambient temperature, olfactory and tactile stimuli associated with the nest.
3. Calls are also sensitive to a variety of purported anxiolytic and anxiogenic drugs, including the benzodiazepines, serotonin agonists, and ligands at the NMDA-glycine receptor complex.
4. In addition to providing a simple test for the anxiolytic properties of drugs, this model may also provide new insights about the development and neurobiology of anxiety. 相似文献
56.
The synthesis is of Tyr(P)-containing peptides by the use of Fmoc-Tyr(PO3Me2)-OH in Fmoc/solid phase synthesis is complicated since, firstly, piperidine causes cleavage of the methyl group from the -Tyr(PO3 Me2)-residue during peptide synthesis and, secondly, harsh conditions are needed for its final cleavage. A very simple method for the synthesis of Tyr(P)-containing peptides using t-butyl phosphate protection is described. The protected phosphotyrosine derivative, Fmoc-Tyr(PO3tBu2)-OH was prepared in high yield from Fmoc-Tyr-OH by a one-step procedure which employed di-t-butyl N,N-diethyl-phosphoramidite as the phosphorylation reagent. The use of this derivative in Fmoc/solid phase peptide synthesis is demonstrated by the preparation of the Tyr(P)-containing peptides, Ala-Glu-Tyr(P)-Ser-Ala and Ser-Ser-Ser-Tyr(P)-Tyr(P). 相似文献
57.
Thirty-five posters were presented at the Workshop on Brain Uptake And Utilization Of Fatty Acids, Lipids, and Lipoproteins.
They were grouped into four categories: (1) mechanisms of lipid uptake and transport to the brain, (2) lipoproteins and polyunsaturated
fatty acids, (3) eicosanoids in brain function, and (4) fatty acids and lipids in brain disorders. This article summarizes
the highlights of the research presented in these posters. The individual abstracts follow these synopses. 相似文献
58.
Elizabeth Z. Bordayo John R. Fawcett Sarita Lagalwar Aleta L. Svitak William H. Frey 《Journal of molecular neuroscience : MN》1996,27(2):185-194
Arachidonic acid (AA), released in response to muscarinic acetylcholine receptor (mAChR) stimulation, previously has been
reported to function as a reversible feedback inhibitor of the mAChR. To determine if the effects of AA on binding to the
mAChR are subtype specific and whether AA inhibits ligand binding to other G protein-coupled receptors (GPCRs), the effects
of AA on ligand binding to the mAChR subtypes (M1, M2, M3, M4, and M5) and to the μ-opioid receptor, β2-adrenergic receptor (β2-AR), 5-hydroxytryptamine receptor (5-HTR), and nicotinic receptors were examined. AA was found to inhibit ligand binding
to all mAChR subtypes, to the β2-AR, the 5-HTR, and to the μ-opioid receptor. However, AA does not inhibit ligand binding to the nicotinic receptor, even
at high concentrations of AA. Thus, AA inhibits several types of GPCRs, with 50% inhibition occurring at 3–25 μM, whereas the nicotinic receptor, a non-GPCR, remains unaffected. Further research is needed to determine the mechanism by
which AA inhibits GPCR function. 相似文献
59.
Robert H. K. Mak 《Pediatric nephrology (Berlin, Germany)》1998,12(8):637-642
Insulin and branched-chain amino acid (BCAA) metabolism was studied in 14 adolescents with uremia on hemodialysis. Glucose
tolerance was measured by intravenous glucose tolerance tests. Insulin sensitivity was measured by the euglycemia clamp technique.
Insulin secretion during constant hyperglycemia was measured by the hyperglycemic clamp technique. Fasting plasma BCAA concentrations
were compared with data from 8 adolescent controls, whereas insulin indices were compared with 8 young adults controls and
with published normal data in adolescents. The patients could be further sub-divided into two groups with respect to their
growth velocity standard deviation score (GVSDS). Group 1 consisted of 7 patients with GVSDS less than −2. This group demonstrated
insulin resistance, glucose intolerance, and low insulin secretion. This group also had low plasma valine, leucine, and isoleucine
concentrations compared with control values. Group 2 consisted of 7 patients with GVSDS more than −2. This group demonstrated
insulin resistance, but normal glucose tolerance and normal insulin secretion. Plasma valine, leucine, and isoleucine concentrations
in group 2 were not different from control values. Total plasma BCAA correlated with glucose tolerance index and with insulin
secretion, but not with insulin sensitivity. Growth failure in uremia is associated with glucose intolerance, hypoinsulinemia,
and low plasma BCAA concentrations. Impaired utilization of conventional energy sources leading to preferential oxidation
of BCAA may contribute to reduced anabolism and growth failure in uremia.
Received October 8, 1997; received in revised form February 3, 1998; accepted February 6, 1998 相似文献
60.
L. Giovannelli F. Casamenti G. Pepeu 《Journal of neural transmission (Vienna, Austria : 1996)》1998,105(8-9):935-948
Summary. A unilateral quisqualic acid lesion was placed in the nucleus basalis magnocellularis of 3- and 24-month-old rats, and the
animals were sacrificed at different times post-surgery. The morphology and the number of the cholinergic neurons of the nucleus
basalis were analyzed by means of immunohistochemistry for cholineacetyltransferase, in order to evaluate the size and severity
of the lesion. Immunohistochemistry for the immediate early gene c-fos was also performed in order to clarify its role in
the process of neurodegeneration following the excitotoxin injection. The DNA laddering and TUNEL techniques were used to
define the type of cell death involved. At short times (4 hr) the lesion induced alterations in the morphology of cholinergic
neurons of the nucleus basalis. Subsequently, a significant decrease in the number of neurons was found in comparison to the
contralateral unlesioned side. In the older animals the loss of cholineacetyltransferase immunoreactivity had an earlier onset
(4 hr) than in the young (24 hr). C-fos expression was induced by the lesion and not by saline injection in the nucleus basalis
and in neighbouring areas of the brain as early as 4 hr after surgery. The c-fos protein was no longer present by 24 hr. Furthermore,
the c-fos gene product was consistently absent from the nuclei of cholinergic cells. The aged animals exhibited a slower and
smaller increase in c-fos as measured by counting the labelled nuclei in the injected area. Analysis of DNA fragmentation
did not provide any evidence for apoptosis as the type of cell death involved in the cholinergic degeneration. These results
indicate that the c-fos protein might have a protective role in the response to excitotoxic lesions. Furthermore, we have
shown that the aged brain displays a reduced ability to produce a c-fos-mediated plastic response to the lesion.
Received December 17, 1997; accepted February 17, 1998 相似文献