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71.
Francesco Botr 《Toxicology in vitro》2003,17(5-6):509-513
A particular field of analytical chemistry applied to forensic toxicology is represented by the anti-doping analysis, where biological samples (urine and in some instances blood) collected, either “in competition” or “out of competition”, from athletes ruled for national/international sport federations, are analyzed to detect the putative use of prohibited substances and methods. Together with the official anti-doping activity to test the athletes (i.e. who engages in competitive sport) for the non-physiological enhancement of sport performance, it is mandatory to activate a new strategy of doping control, that should necessarily comprise a deep and exhaustive toxicological evaluation of the entire spectrum of doping substances and methods. An outline of the present status and of the future trends of the antidoping research is here presented, showing that most of the new tasks could greatly benefit from an approach based on in vitro methods, ranging from specific toxicity studies to the possible detection of new forms of doping. 相似文献
72.
The authors review the latest theories of peripheral nerve regeneration and repair. They present their research on nerve regeneration including the alterations in the mother cell body, and in the distal part of the axon, and the time required to reach the best production of amino acids for cytoskeleton reconstruction. Other research of particular interest which is presented regards the chemotactic arrangement of motor and sensory axons inside a vein. This research has shown that the axons are able to find their way to the appropriate (sensory or motor) distal endoneural tubes.Adoption phenomena are also presented.The discussion of surgery includes the type (suture, glueing, grafts, tubulization) and the time of surgical repair. Timing and repair strategies are related to the site of the lesion (which can require that a greater or smaller amount of cytoskeleton be reconstructed), the type of the injury, the state of surrounding tissues, the age of the patients, injuries to muscles, tendons, bones, vessels and skin. A scheme of strategy is proposed. 相似文献
73.
Michael C Graves Milan Fiala Lu Anne V Dinglasan Nancy Q Liu James Sayre Francesco Chiappelli Cees van Kooten Harry V Vinters 《Amyotrophic lateral sclerosis and other motor neuron disorders》2004,5(4):213-219
Recent studies have shown inflammatory markers in affected neural tissues of amyotrophic lateral sclerosis (ALS) patients. We examined immunocytochemically spinal cord tissues of six patients with ALS, two with corticospinal tract degeneration secondary to cerebral infarcts and three control subjects without neuropathologic abnormalities. ALS spinal cords had dense macrophage infiltration (one log greater than control spinal cords) involving the white and gray matter, with heaviest infiltration of lateral and ventral columns and, in one patient, prefrontal gyrus and the occipital lobes of the brain. Macrophages in ALS spinal cord showed strong expression of cyclooxygenase-2 (COX-2) (one log greater than control tissues) and inducible nitric oxide synthase. In the gray matter, macrophages surrounded and appeared to phagocytize neurons (NeuN-positive) that appeared to be dying. Vessels showed damage to the tight junction protein ZO-1 in relation to perivascular CD40 receptor-positive macrophages and CD40 ligand-positive T lymphocytes. ALS spinal cords, but not control cords, were sparsely infiltrated with mast cells. In control cases with corticospinal tract degeneration following hemispheric cerebral infarction, macrophage infiltration of the white matter was COX-2-negative and restricted to lateral and anterior corticospinal tracts. Our data suggest that inflammation in ALS spinal cord and cortex is based on innate immune responses by macrophages and mast cells and adaptive immune responses by T cells. 相似文献
74.
Francesco Martino Pasquale Pignatelli Eliana Martino Francesco Morrone Roberto Carnevale Serena Di Santo Barbara Buchetti Lorenzo Loffredo Francesco Violi 《Journal of the American College of Cardiology》2007,49(19):1974-1981
OBJECTIVES: The aim of the study was to analyze the behavior of oxidative stress and its interplay with CD40L, a protein that is implicated in atherosclerosis, in hypercholesterolemic children. BACKGROUND: Oxidative stress has been suggested to play a major role in premature atherosclerosis. METHODS: Forty-one children with hypercholesterolemia (mean age 9.28 +/- 0.5 years) and 40 children with normocholesterolemia (mean age 9.02 +/- 0.69 years) were matched for gender and age. Within each group, children were classified as having or not having a family history of cardiovascular disease. Serum levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative stress, and plasma levels of soluble CD40L (sCD40L) were measured in each child. In a subgroup of children with high (n = 8) or normal (n = 8) levels of serum cholesterol, platelet p38 mitogen-activated protein (MAP) kinase phosphorylation, a protein involved in the activation of nicotinamide adenine dinucleotide phosphate oxidase, was determined. RESULTS: Children with hypercholesterolemia had higher values of 8-OHdG and sCD40L compared with control subjects (0.55 +/- 0.06 ng/ml vs. 0.21 +/- 0.02 ng/ml, p < 0.001 and 0.55 +/- 0.04 ng/ml vs. 0.19 +/- 0.03 ng/ml, p < 0.001, respectively). A significant correlation between 8-OHdG and sCD40L was observed in children with high (r = 0.676, p < 0.001) or normal (r = 0.878, p < 0.001) levels of cholesterol. Children with a family history of cardiovascular disease tended to have higher values of 8-OHdG and sCD40L, but the difference was not significant. Analysis of platelet p38 MAP kinase showed that it was phosphorylated more in children with hypercholesterolemia compared with control subjects (36.8 +/- 5.8 AU vs. 8.0 +/- 4.5 AU, p < 0.001 respectively). CONCLUSIONS: Children with hypercholesterolemia have an early increase of oxidative stress that may be responsible for up-regulation of CD40L and potentially predispose to premature atherosclerosis. 相似文献
75.
76.
Emanuele Lezoche M.D. Alessandro M. Paganini M.D. Ph.D. Francesco Carlei M.D. Francesco Feliciotti M.D. Davide Lomanto M.D. Ph.D. Mario Guerrieri M.D. 《World journal of surgery》1996,20(5):535-542
n
= 2), port site infection (
n
= 2), and subumbilical hematoma (
n
= 1). Major morbidity was bile leakage from the cystic duct stump in two cases due to clips or transcystic duct drainage displacement,
respectively. One elderly, high risk patient died after being referred for several failed attempts of endoscopic clearance;
she died from cardiogenic shock 3 days after successful laparoscopic treatment. Laparoscopic CBD exploration is feasible and
safe in most patients, with short-term results that compare favorably with the results of sequential ES/LC reported in the
literature. 相似文献
77.
Francesco Ferrozzi Davide Bova Fabio Campodonico 《Seminars in Ultrasound, CT and MRI》1997,18(2):115-121
Since the advent of CT, secondary neoplastic lesions of the kidneys have been detected with increasing frequency. After reviewing a large series of cases of renal metastases, we have been able to classify the CT findings into seven major categories that are discussed and illustrated in this article. The differential diagnoses between metastatic disease of the kidneys and other lesions such as renal infarctions, renal lymphoma, and primary malignancies are also considered. 相似文献
78.
Teresa Coccini Luciano Maestri Francesco S. Robustelli della Cuna L. Bin Lucio G. Costa Luigi Manzo 《Archives of toxicology》1996,70(11):736-741
Styrene is stereoselectively oxidized by cytochrome P450 to its reactive metabolite, styrene oxide. The (R)- and (S)-enantiomers
of styrene oxide can be conjugated with glutathione (GSH) to both (R)- and (S)-diastereoisomers of the specific mercapturic
acids, N-acetyl-S-(1-phenyl-2-hydroxyethyl)-L-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-L-cysteine (M2). Several investigations have indicated different toxic potential of the (R)- and (S)-configurations of styrene
oxide and its GSH- and N-acetyl-conjugates. In this study the mercapturic acid diastereoisomers were measured in the urine
of rats exposed to styrene in combination with ethanol, a good inducer of styrene metabolism. Male Sprague-Dawley rats were
given an isocaloric liquid diet containing ethanol (5% w/v) for 3 weeks. Starting from the 2nd week, the animals were also
exposed to styrene vapours (300 ppm, 6 h/day, 5 days/week) in a dynamic exposure chamber. Both the (R)- and (S)-diastereoisomers
of the M1 and M2 as well as the conventional biomarkers, mandelic acid (MA) and phenylglyoxylic acid (PGA) were measured in
urinary samples. Approximately 30 and 25% reduction of the levels of brain non-protein sulfhydryls (NPS) was observed in the
animals given styrene and ethanol, respectively, while the combined ethanol and styrene treatment resulted in a 60% decrease.
Ethanol consumption also resulted in higher urinary levels of the M1-R, M1-S and M2 metabolites associated with increased
M1-R/S ratio and higher urinary MA excretion compared to animals treated with styrene. These results suggest that the urinary
mercapturic acid diastereoisomers may be used as a noninvasive tool to examine stereoselective patterns of styrene metabolism
in vivo, as well as their alterations caused by ethanol. These compound-specific mercapturic acids may also be valuable indicators
of styrene-induced disorders of GSH homeostasis in nonaccessible organs.
Received: 19 December 1995/Accepted: 10 May 1996 相似文献
79.
80.
Anna Pizzirusso Patrizia Oliva Sabatino Maione Michele D’Amico Francesco Rossi L. Berrino 《Naunyn-Schmiedeberg's archives of pharmacology》1998,357(5):514-518
In order to evaluate the role played by vasopressin on pressor responses elicited by stimulation of the periaqueductal gray
(PAG) area by excitatory amino acids we carried out in vivo studies in genetically vasopressin deficient rats (Brattleboro).
Microinjections of l-glutamic acid (glutamate, 0.6 to 60 nmol/rat) or N-methyl-d-aspartic acid (NMDA, 0.07 to 7 nmol/rat)
into the PAG area of freely moving Brattleboro rats induced increases of arterial blood pressure values significantly lower
than those obtained in Long Evans rats (control) (glutamate in Brattleboro rats: from +2±1 mmHg to 16±3 mmHg; glutamate in
Long Evans rats: from +16±2 mmHg to +36±4 mmHg; NMDA in Brattleboro rats: from +5±2 mmHg to +34 ±8 mmHg; NMDA in Long Evans
rats: from +18±7 mmHg to 80±9 mmHg; n=5). Similarly, in anaesthetized Brattleboro rats (urethane 1.2 g/kg i.p.) pressor responses to NMDA microinjections (0.7
nmol/rat) into the PAG area were significantly lower than in Long Evans rats (controls) (+15±3 mmHg vs +24±4 mmHg). In Long
Evans rats NMDA injection also reversed blood pressure decrease induced by ganglionic blocker, hexamethonium and/or losartan
(3 mg/kg i.v.), an AT1 receptor antagonist. In Brattleboro rats, NMDA injection did not reverse blood pressure decreases induced
by hexamethonium (5 mg/kg i.v.). Moreover, hexamethonium induced blood pressure decrease was not reversed by acetylcholine
injection (137 nmol/rat) into the PAG area of anaesthetized Long Evans rats, but if injected before hexamethonium, acetylcholine
was able to increase blood pressure (+25±3 mmHg). Our results document: i) the importance of the PAG area in the control
of cardiovascular system; ii) the involvement of excitatory amino acids in the neural control of vasopressin release; iii)
the close relationship between glutamate and vasopressin in the central blood pressure regulation.
Received: 1 April 1997 / Accepted: 2 February 1998 相似文献