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31.
AJ Levi 《Journal of clinical pathology》1988,41(2):236-237
32.
Levi MH Bartell J Gandolfo L Smole SC Costa SF Weiss LM Johnson LK Osterhout G Herbst LH 《Journal of clinical microbiology》2003,41(5):2147-2152
The characterization of a novel Mycobacterium sp. isolated from granulomatous skin lesions of moray eels is reported. Analysis of the hsp65 gene, small-subunit rRNA gene, rRNA spacer region, and phenotypic characteristics demonstrate that this organism is distinct from its closest genetic match, Mycobacterium triplex, and it has been named M. montefiorense sp. nov. 相似文献
33.
Liu JQ; Bai XF; Shi FD; Xiao BG; Li HL; Levi M; Mustafa M; Wahren B; Link H 《International immunology》1998,10(8):1139-1148
Induction of mucosal tolerance by inhalation of soluble peptides with
defined T cell epitopes is receiving much attention as a means of
specifically down-regulating pathogenic T cell reactivities in autoimmune
and allergic disorders. Experimental autoimmune encephalomyelitis (EAE)
induced in the Lewis rat by immunization with myelin basic protein (MBP)
and Freund's adjuvant (CFA) is mediated by CD4+ T cells specific for the
MBP amino acid sequences 68-86 and 87-99. To further define the principles
of nasal tolerance induction, we generated three different MBP peptides
(MBP 68-86, 87-99 and the non- encephalitogenic peptide 110-128), and
evaluated whether their nasal administration on day -11, -10, -9, -8 and -7
prior to immunization with guinea pig MBP (gp-MBP) + CFA confers protection
to Lewis rat EAE. Protection was achieved with the encephalitogenic
peptides MBP 68-86 and 87-99, MBP 68-86 being more potent, but not with MBP
110-128. Neither MBP 68-86 nor 87-99 at doses used conferred complete
protection to gp-MBP-induced EAE. In contrast, nasal administration of a
mixture of MBP 68-86 and 87-99 completely blocked gp-MBP-induced EAE even
at lower dosage compared to that being used for individual peptides. Rats
tolerized with MBP 68-86 + 87-99 nasally showed decreased T cell responses
to MBP reflected by lymphocyte proliferation and IFN-gamma ELISPOT assays.
Rats tolerized with MBP 68-86 + 87-99 also had abrogated MBP-reactive
IFN-gamma and tumor necrosis factor-alpha mRNA expression in lymph node
cells compared to rats receiving MBP 110-128 nasally, while similar low
levels of MBP-reactive transforming growth factor-beta and IL-4 mRNA
expressing cells were observed in the two groups. Nasal administration of
MBP 68-86 + 87-99 only slightly inhibited guinea pig spinal cord
homogenate-induced EAE, and passive transfer of spleen mononuclear cells
from MBP 68-86 + 87-99-tolerized rats did not protect naive rats from EAE.
Finally, we show that nasal administration of MBP 68-86 + 87-99 can reverse
ongoing EAE induced with gp-MBP, although higher doses are required
compared to the dosage needed for prevention. In conclusion, nasal
administration of encephalitogenic MBP peptides can induce antigen-specific
T cell tolerance and confer incomplete protection to gp-MBP-induced EAE,
and MBP 68-86 and 87-99 have synergistic effects. Non-regulatory mechanisms
are proposed to be responsible for tolerance development after nasal
peptide administration.
相似文献
34.
Osteonecrosis in HIV: a case-control study 总被引:2,自引:0,他引:2
Scribner AN Troia-Cancio PV Cox BA Marcantonio D Hamid F Keiser P Levi M Allen B Murphy K Jones RE Skiest DJ 《Journal of acquired immune deficiency syndromes (1999)》2000,25(1):19-25
BACKGROUND: Osteonecrosis (avascular necrosis) has been infrequently reported in HIV-infected patients. It is not known whether HIV itself is an independent risk factor for osteonecrosis. METHODS: We identified 25 patients with osteonecrosis from 1984 to 1999 from a large county teaching hospital and two large practices in Dallas County that specialize in HIV-disease related therapy. A retrospective chart review was performed to evaluate potential risk factors for osteonecrosis. Each case was matched with two controls for HIV positive status and date of osteonecrosis diagnosis. RESULTS: In the study, 22 of 25 (88%) case patients had at least one osteonecrosis risk factor compared with 24 of 50 (48%) controls, p =.003. The most common osteonecrosis risk factors were hyperlipidemia (32%), alcoholism (28%), pancreatitis (16%), corticosteroids (12%), and hypercoaguability (12%). Of the cases, 12% were idiopathic. Multiple joints were involved in 72% of cases. Four of the case patients compared with none of the controls received megesterol acetate before the diagnosis of osteonecrosis, p =.01. No significant differences were found between cases and controls with respect to liver function tests, testosterone levels, triglyceride levels, cholesterol levels, or CD4 cell counts. Saquinavir was independently associated with osteonecrosis, p <.05. However, no differences in overall use of protease inhibitors among cases and controls were noted: 79% versus 76%, respectively. CONCLUSIONS: The increased incidence of osteonecrosis in HIV/AIDS may be due to an increased frequency of risk factors previously associated with osteonecrosis such as hyperlipidemia, corticosteroid use, alcohol abuse, and hypercoaguability. Use of protease inhibitors was not independently associated with osteonecrosis. 相似文献
35.
G Pierquin J Deroover S Levi T Masson F Hayez-Delatte N Van Regemorter 《American journal of medical genetics》1989,33(4):483-484
We report on two sibs with Dandy-Walker malformation and tetramelic postaxial polydactyly. We conclude that this is a new autosomal recessive syndrome. 相似文献
36.
F. C. Howarth Allan J. Levi Jules C. Hancox 《Pflügers Archiv : European journal of physiology》1996,431(5):713-722
The delayed rectifier potassium current (I
K) is known to be important in action potential repolarisation and may contribute to the diastolic pacemaker depolarisation
in pacemaker cells from the heart. In this study, using whole-cell patch clamp, we investigated the characteristics of I
K in morphologically normal cells from the atrioventricular node (AVN) and ventricle of the rabbit heart. Cells were held at
−40 mV and 5 μM external nifedipine was used to block L-type calcium current (I
Ca,L). Significant I
K was observed with pulses to potentials more positive than −30 mV. The steady-state activation curve in both cell types showed
maximal activation at between + 10 and + 20 mV. Half-maximal activation of I
K occurred at −4.9 and −4.1 mV with slope factors of 8.3 and 12.4 mV in ventricular and AVN cells, respectively. Using pulses
of increasing duration, significant I
K tails after repolarisation from + 40 mV were observed with pulses of 20 ms and increased with pulses up to 100–120 ms in
both cell types. Pulses of longer duration did not activate further I
K and this suggested that only the rapid component of I
K, called I
Kr, was present in either cell type. Moreover, I
K tails after pulses to all potentials were blocked completely by E-4031, a selective blocker of I
Kr. The reversal potential of I
K varied with the concentration of external K. Superfusion of AVN cells with medium containing 4, 15 and 40 mM [K+]o resulted in reversal potentials of −81, −56 and −32 mV, respectively, which are close to values predicted if the I
K channel were highly selective for K. The time constants for deactivation of I
K in ventricle and AVN on return to −40 mV after a 500-ms activating pulse to + 60 mV were 480 ms and 230 ms, respectively.
The faster deactivation of I
K in AVN cells was a distinguishing feature and suggests that there may be differences in the I
Kr channel protein between ventricular and AVN cells.
Received: 24 July 1995 /Received after revision: 20 October 1995 /Accepted: 23 October 1995 相似文献
37.
Using electrophysiological and radiotracer studies in parallel, we have investigated the characteristics of the endogenous Na+-dependent amino acid transporter (system B0,+) in Xenopus oocytes with regard to ion dependence, voltage dependence and transport stoichiometry. In voltage-clamped oocytes (–60 mV) superfusion with saturating concentrations of amino acids (1 mM) in 100 mM NaCl resulted in reversible, inward currents (mean±SEM): alanine, 1.83±0.09 nA (n=21); arginine, 2.54±0.18 nA (n=17); glutamine, 1.73±0.10 nA (n=19). Only arginine evoked a current in choline medium (0.50±0.13 nA, n=10), whereas Cl– replacement had no effect on evoked currents. The glutamine-evoked current was saturable (I
max=1.73 nA, glutamine K
m=0.12 mM) and linearly dependent upon voltage between –90 and –30 mV. Using direct and indirect (activation) methods, we found that transport can proceed with Na+/amino acid coupling stoichiometry of either 11 or 21, but coupling was the same for each amino acid tested (alanine, arginine and glutamine) within a batch of oocytes (i.e. from a single toad). Despite the net single positive charge on arginine, the magnitude of the net transmembrane charge movement during Na+-coupled arginine transport was identical to that for the zwitterionic neutral amino acids glutamine and alanine; this may be explained by a concomitant stimulation of K+ efflux during arginine transport with a putative coupling of 1 K+1 arginine. 相似文献
38.
Yaron Bar-Dayan M. Eric Gershwin Yair Levi Howard Amital Dr. Yehuda Shoenfeld 《Immunologic research》1998,18(2):117-123
Primary biliary cirrhosis (PBC) is a chronic, progressive cholestatic liver disease, which is invariably fatal. Circumstantial and indirect evidence suggests that autoimmune mechanisms have a role in the pathogenesis of PBC. Antimitochondrial antibodies (AMA) are highly sensitive and specific markers that can predict the development of the disease in a healthy individual. Long-term administration of ursodeoxycholic acid (UDCA), a naturally occurring bile acid, safely slows the progression of PBC, delays the need for liver transplantation, and postpones death. An effort should be made to identify the patients with PBC in the asymptomatic stage by the presence of AMA and to conduct a clinical trial in order to assess the benefit of long-term administration of UDCA on the prevention of the overt disease in these individuals. 相似文献
39.
A computerized decision support system is presented. The system is used to aid in the situation of patient selection for the purpose of dental education and utilizes the PERT/CPM methodology and decision tables. It runs on a microcomputer and written in Basic. The input is a list of patient's needs, and the output is a tentative treatment plan, the chair time needed to complete the treatment, its cost, and the probability that the student will finish it on time. 相似文献
40.
M Lichter G Fleischner R Kirsch A J Levi K Kamisaka I M Arias 《The American journal of physiology》1976,230(4):1113-1120
Sephadex G-100 chromatography of rat liver supernatant after addition of [125I]T3 revealed four peaks of protein-bound radioactivity in the void volume, albumin, ligandin, and Z-containing regions, respectively. The peaks were identified by cochromatography of BSP and [125I]T3 and immonodiffusion with antiratligandin IgG and antirat Z IgG. Binding of [125I]T4 to rat liver supernatant occurred in void volume, albumin, and Z regions only. Studies in vivo reveal a pattern of [125I]T3 binding to rat liver supernatant fractions quantitatively different from that observed in vitro. [125I]T4 binding to liver supernatant fractions in vivo occurred in all four peaks. BSP or bilirubin added to liver supernatant decreased T3 and T4 binding by each fraction. Flavaspidic acid inhibited binding of T3 and T4 to albumin, ligandin, and Z protein. Phenobarbital pretreatment of rats increased binding of T3 by ligandin and of T4 by albumin-containing fractions. Circular dichroism studies with purified rat liver ligandin suggest that T3 and T4 bind competitively to the same site as does bilirubin; the association constants of T3 and T4 for ligandin are 10(6) and 10(5) M-1, respectively. T4 was bound only by purified ligandin and not by ligandin in liver supernatant. To determine whether unconjugated bilirubin interferes with hepatic uptake of T3, [125I]T3 was administered to icteric homozygous and phenotypically normal heterozygous Gunn rats. Hepatic uptake and supernatant binding [125I]T3 were significantly reduced in homozygous Gunn rats. Hepatic uptake of [125I]T3 was also reduced in vivo by infusion of BSP with or without flavaspidic acid. BSP infusion abolished [125I]T3 binding to ligandin; BSP and flavaspidic acid abolished binding to ligandin and Z. These observations suggest that ligandin and Z protein are thyroid hormone binding proteins in rat liver cytosol and may influence the net flux of iodothyronies from plasma into the liver. 相似文献