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121.
The delayed neurotoxic organophosphate, diisopropylfluorophosphate (DFP) binds with high affinity to membrane-bound proteins
from chicken nerve tissues. The autoradiographic distribution of [3H]DFP binding sites in spinal cord sections of chicken showed higher concentrations of binding sites in gray matter than in
white matter. In the cervical region, fairly high densities of [3H]DFP binding sites were found in laminae X and to a lesser extent, in the ventral horn gray matter. To identify the membrane-associated
DFP-binding proteins, detergent-solubilized membranes were labeled widi 5-10nM [3H]DFP (10pmol/mg protein) for 70 min at 37°C. Gel-exclusion chromatography of the [3H]DFP-radiolabeled membranes indicated at least two major radioactive proteins with apparent molecular weights of 150-670
kDa and 40-129 kDa. Although we could not identify the high affinity DFP binding proteins, the autoradiographic experiments
clearly demonstrated that the DFP binding proteins localized on gray matter of chicken spinal cord. 相似文献
122.
Hansen O 《Pflügers Archiv : European journal of physiology》1999,437(4):517-522
Purified Na+/K+-ATPase (EC 3.6.1.37) isolated from the rectal gland of Squalus acanthias was characterized in ouabain-binding studies and with respect to isoform(s) of the α peptide. To avoid enzyme inactivation
[3H]ouabain equilibrium binding was carried out at 20°C. The heterogeneity of Na+/K+-ATPase isolated from shark rectal gland was similar in [3H]ouabain binding as previously seen in hydrolytic studies. The binding isotherms were compatible with the existence of a
high-affinity (K
dis 0.69 nM) and a low-affinity (K
dis 42 nM) component of 1.46 and 0.79 nmol.(mg protein)–1, respectively. In Western blots the α peptide of the enzyme hybridized with an isoform-specific polyclonal antibody raised
to an α3-specific region of the large intracellular domain of rat Na+/K+-ATPase, but not with the supposed α3-specific monoclonal antibody MA3-915 with its epitope near the N-terminus. Semi-quantitative analysis of the reaction of
the α3-specific polyclonal antibody with the α peptide from the shark enzyme compared to the reaction with α peptide from rat brain
enzyme indicated that this region is not exactly the same in the two species. The α peptide of shark enzyme was not recognized
by α1- or α2-specific polyclonal antibodies, or by the α1-specific monoclonal antibodies 3B and F6. The large intracellular domain of Na+/K+-ATPase from shark rectal gland thus seems to be α3-like and no α isoform heterogeneity seems able to account for the heterogeneity seen in ouabain binding.
Received: 7 August 1998 / Accepted: 6 November 1998 相似文献
123.
Arthurs BP Khalil MK Chagnon F Lindley SK Anderson DP Burnier M 《Ophthalmology》1999,106(12):2387-2390
OBJECTIVE: To present a patient with systemic lupus erythematosus who developed infarction and melting of the orbit secondary to her systemic disease. DESIGN: A case report. PARTICIPANT: A 61-year-old white woman with a 5-year history of systemic lupus erythematosus. METHODS: The patient presented with left orbital pain, limitation of extraocular movements, and a fistula from the ethmoid sinus to the upper eyelid. A detailed examination with computerized tomography, ultrasound, and a comprehensive medical evaluation with laboratory testing was performed. Histopathologic analysis with special stains of the orbital tissues was also performed. RESULTS: Histopathologic examination of the biopsy specimens revealed the features of an inflammatory process involving the orbit, similar to a panniculitis. These include a lymphocytic reaction with a predominance of plasma cells, vasculitis with occlusion, and thickening of the vessel walls, necrosis, and hyalinization of fat. CONCLUSION: This is a unique case in which infarction and melting of the entire orbital structures occurred in the presence of systemic lupus erythematosus. The underlying disease process is a lupus-related panniculitis. The authors stress that this is a very rare entity and that other diseases should be ruled out before entertaining this diagnosis. 相似文献
124.
Nestby P Schoffelmeer AN Homberg JR Wardeh G De Vries TJ Mulder AH Vanderschuren LJ 《Psychopharmacology》1999,142(3):309-317
It has been postulated that opioid systems in the brain may play a role in ethanol reinforcement. In this respect, μ- and
δ-opioid receptors may mediate the rewarding effects whereas κ receptors are thought to mediate the aversive effects of opioids.
Accordingly, long-acting benzomorphans such as bremazocine, that simultaneously act as μ and δ receptor antagonists and κ receptor agonists may be particularly effective in reducing ethanol self-administration. Therefore, we studied the effect
of bremazocine on oral ethanol self-administration in rats using a paradigm [unrestricted free-choice drinking of 10% (v/v)
ethanol], previously shown to cause long-term neuroadaptations in the nucleus accumbens and caudate putamen. Bremazocine (0.1 mg/kg,
once daily for five consecutive days) reduced ethanol drinking by about 50% during the active period of the animals, whereas
the intake of sucrose (3–10% w/v) was affected neither in naive nor in ethanol-experienced rats. This effect of bremazocine
appeared not to be secondary to its acute sedative effect or the slight increase in total fluid consumption. Unlike bremazocine,
the selective κ-opioid receptor agonist U50,488H (10 mg/kg, once daily) inhibited ethanol drinking only during the first of 5 treatment days
and the opioid receptor antagonist naltrexone (0.3–10 mg/kg, once daily) only caused a modest (about 20%) suppression of ethanol
drinking during the first hours after drug injection. Thus, bremazocine appears to be far more potent than the clinically
applied drug naltrexone in this respect. Our data further support the role of opioid receptors in ethanol reinforcement and
indicate that long-acting mixed-action opioids such as bremazocine may be useful as adjuvants for the clinical management
of ethanol addiction.
Received: 1 July 1998/Final version: 3 September 1998 相似文献
125.
G. Olmos R. Alemany J. A. García-Sevilla 《Naunyn-Schmiedeberg's archives of pharmacology》1996,354(6):709-716
I2-imidazoline receptors labelled with [3H]-idazoxan in the rabbit and rat brains displayed high and low affinity, respectively, for the guanidide amiloride; reinforcing the previous definition of I2A-imidazoline receptors expressed in the rabbit brain and Its-imidazoline receptors expressed in the rat brain. Other drugs tested displayed biphasic curves in competition experiments, indicating the existence of high and low affinity sites for both subtypes of I2-imidazoline receptors. Among the drugs studied, bromoxidine, moxonidine, (+)- and (-)-medetomidine and clorgyline were more potent on the high and/or low affinity sites of 12B- than on their corresponding of I2A-imida-zoline receptors (K
iH
ratios 20 to 65). No correlation was found for the potencies of the drugs tested at the low affinity sites of both I2-imidazoline receptor subtypes. Preincubation (30 min at 25°°C) with 10-6 M clorgyline reduced by 60% the B
max of [3H]-idazoxan binding to I2 B-imidazoline receptors in the rat brain, but it did not affect the binding parameters of the radioligand saturation curves to I2A-imidazoline receptors in the rabbit brain. These results indicated that I2A- and I2B-imidazoline receptor subtypes differ in the pharmacological profiles of their high and low affinity sites and in the ability to irreversibly bind clorgyline. In rat cortical membranes western blot detection of immunoreactive imidazoline receptor proteins revealed a double band of 29/30 kDa and two less intense bands of 45 and 66 kDa. In rabbit cortical membranes the antibody used detected proteins of 30, 57 and 66 kDa. It is suggested that different imidazoline receptor proteins (45 vs 57 kDa) may account for the different pharmacological profiles of I2-imidazoline receptor subtypes. 相似文献
126.
A genetic analysis of amphetamine-induced hyperthermia was conducted in inbred mice of the strains Balb/c and C3H and in their F1F2 and backcross generations. The results of biometric analysis indicate that the effect of amphetamine on body temperature is genetically determined. The mode of inheritance characterized by a partial dominance (Balb/C over C3H strain). However, a possible matermal effect of C3H can overcome the dominant effect in male progenies and inhibit amphetamine hyperthermic effect. 相似文献
127.
Neuronal types contributing to the inner plexiform layer of the cat retina are described based primarily on light microscopy of Golgi-impregnated retinal whole-mounts. Cells have been characterized on morphological criteria that include dendritic branching patterns, dendritic tree sizes, cell body sizes and stratification of processes in the inner plexiform layer. Nine different types of bipolar cell, 22 different types of amacrine cell and 23 different types of ganglion cell can be distinguished using one or more of these morphological criteria. The significance of the different morphological types of cells is discussed, particularly in relationship to the functional bisublamination of the cat inner plexiform layer. 相似文献
128.
129.
130.
Alpha1-acid glycoprotein (alpha1-AG) was purified from human sera, and its binding properties with respect to psychotropic drugs were examined by equilibrium dialysis methods in order to clarify the specificity of binding. Radioactive imipramine, a tricyclic antidepressant, was used as the primary ligand. Other drugs, representative of different classes, were tested as potential inhibitors of the alpha1-AG-imipramine binding. The K(a) for imipramine was 2.8 x 10(5) (+/- 0.8) M(-10 (mean +/- S.D.). Chlorpromazine, fluphenazine, thioridazine, loxapine and thiothixene, which are antipsychotic drugs, were competitive inhibitors of imipramine binding, and their K(a) values were in the same range. Propranolol, haloperidol and diazepam were also competitive inhibitors but their affinities were lower. Molindone, an indolic antipsychotic, when tested at the same concentrations as the other drugs, did not affect imipramine binding. Trihexyphenidyl, an anti-Parkinson drug, was a potent but noncompetitive inhibitor. These data identify the antidepressant and major tranquilizer drugs that exhibit high affinity for alpha1-AG and indicate that alpha1-AG may account for 40 per cent of total imipramine bound in serum. Since in psychiatric clinical practice two drugs are frequently administered together, possible competitive effects are discussed as well as the potential role of alpha1-AG in psychiatric illness. 相似文献