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81.
The role of histone acetylation in SMN gene expression 总被引:7,自引:0,他引:7
Kernochan LE Russo ML Woodling NS Huynh TN Avila AM Fischbeck KH Sumner CJ 《Human molecular genetics》2005,14(9):1171-1182
82.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
83.
Karina R B Bastos Renato Barboza Luiz Sardinha Momtchilo Russo José M Alvarez Maria Regina D'Império Lima 《Journal of interferon & cytokine research》2007,27(5):399-410
Besides the established role of interleukin-12 (IL-12) and IL-18 on interferon-gamma (IFN-gamma) production by natural killer (NK), T, and B cells, the effects of these cytokines on macrophages are largely unknown. Here, we investigated the role of IL-12/IL-18 on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production by CD11b(+) adherent peritoneal cells, focusing on the involvement of endogenously produced IFN-gamma. C57BL/6 cells released substantial amounts of NO when stimulated with IFN-gamma or lipopolysaccharide (LPS), but failed to respond to IL-12 or IL-18 or both. However, IL-12/IL-18 pretreatment was able to program these cells to release 6-8-fold more NO and TNF-alpha in response to LPS or Trypanosoma cruzi stimulation, with NO levels directly correlating with macrophage resistance to intracellular parasite growth. Analysis of IL-12/IL-18-primed cells from mice deficient in IFN-gamma, IFNGR, and IFN regulatory factor-1 (IRF-1) revealed that these molecules were essential for LPS-induced NO release, but TNF-alpha production was IFN-gamma independent. Conversely, the myeloid differentiation factor 88 (MyD88)-dependent pathway was indispensable for IL-12/IL-18-programmed LPS-induced TNF-alpha production, but not for NO release. Contaminant T and NK cells largely modulated the IL-12/IL-18 programming of LPS-induced NO response through IFN-gamma secretion. Nevertheless, a small population of IFN-gamma(+) cells with a macrophage phenotype was also identified, particularly in the peritoneum of chronically T. cruzi-infected mice, reinforcing the notion that macrophages can be an alternative source of IFN-gamma. Taken together, our data contribute to elucidate the molecular basis of the IL-12/IL-18 autocrine pathway of macrophage activation, showing that endogenous IFN-gamma plays an important role in programming the NO response, whereas the TNF-alpha response occurs through an IFN-gamma-independent pathway. 相似文献
84.
Antonella Gambale Roberta Russo Immacolata Andolfo Lucia Quaglietta Gianluca De Rosa Valentina Contestabile Lucia De Martino Rita Genesio Piero Pignataro Sabrina Giglio Mario Capasso Rosanna Parasole Barbara Pasini Achille Iolascon 《Clinical genetics》2019,96(4):359-365
Cancer predisposition syndromes (CPS) result from germline pathogenic variants, and they are increasingly recognized in the etiology of many pediatric cancers. Herein, we report the genetic/genomic analysis of 40 pediatric patients enrolled from 2016 to 2018. Our diagnostic workflow was successful in 50% of screened cases. Overall, the proportion of CPS in our case series is 10.9% (20/184) of enrolled patients. Interestingly, 12.5% of patients achieved a conclusive diagnosis through the analysis of chromosomal imbalance. Indeed, we observed germline microdeletions/duplications of regions encompassing cancer-related genes in 50% of patients undergoing array-CGH: EIF3H duplication in a patient with infantile desmoplastic astrocytoma and low-grade Glioma; SLFN11 deletion, SOX4 duplication, and PARK2 partial deletion in three neuroblastoma patients; a PTPRD partial deletion in a child diagnosed with glioblastoma multiforme. Finally, we identified two cases due to DICER1 germline mutations. 相似文献
85.
A protocol for the simultaneous visualization of minor and majorsatellite DNA by primed in situ DNA synthesis PRINS was developedin cytokinesisblocked murine splenocytes. After individuationof optimal experimental conditions, a micronucleus MN test wascarried out by treating splenocytes in vitro with the clastogenicagent mitomycin C and the aneugenic compound Colcemid. It wasfound that PRINS gives highly reproducible results, also comparablewith the literature on MN results obtained by fluorescent insitu hybridization FISH. Therefore the PRINS methodology maybe proposed as a fast alternative to FISH for the characterizationof induced MN.
1To whom correspondence should be addressed 相似文献
86.
87.
Vaccine immune response and side effects with the use of acetaminophen with influenza vaccine. 下载免费PDF全文
P A Gross R A Levandowski C Russo M Weksler J Bonelli S Dran G Munk S Deichmiller R Hilsen R F Panush 《Clinical and Vaccine Immunology : CVI》1994,1(2):134-138
The purpose of this study was to determine whether acetaminophen impairs the immune response to influenza vaccine. Influenza vaccine is an under-utilized preventive measure, partly because of the unfounded perception that fever and myalgias frequently follow vaccination. While acetaminophen may decrease these infrequent side effects, it may also alter the immune response to vaccination. We compare the effect of acetaminophen with placebo on the humoral immune response to the 1991-1992 commercially available influenza vaccine. We studied 60 healthy, elderly subjects from a geriatric clinic and 20 infirm, elderly subjects from a nursing home. The subjects were randomly assigned to receive placebo or acetaminophen (1,000 mg every 6 h) for 2 days. Acetaminophen did not depress or enhance the immune development of serum hemagglutination inhibition antibody to the three vaccine antigens. The systemic side effects of fever and myalgia were uncommon in both groups. The healthy elderly subjects mounted a significantly better immune response to the influenza virus A/Taiwan/1/86 (H1N1) vaccine strain than did the infirm elderly subjects (geometric mean titer, 115 versus 51; P = 0.003). The functional activity score obtained by using the chronic healthy evaluation component of the Acute Physiology and Chronic Health Evaluation system could be used to distinguish the healthy from the infirm elderly (scores of 1.27 versus 3.75, P < 0.001). Acetaminophen neither depressed nor enhanced the serum antibody response to the vaccine in the healthy and infirm elderly subjects studied. 相似文献
88.
Long-term growth of human T cell lines and clones on anti-CD3 antibody-treated tissue culture plates 总被引:1,自引:0,他引:1
Long-term growth of antigen-specific human T cells requires, in addition to IL-2, periodic exposure to antigen and accessory cells. In certain cases, accessory cells are not available or their presence in culture is undesired. We have developed a method of growing and sustaining human T cell lines and clones in long-term tissue culture in the absence of specific antigen or accessory cells. The requirement for antigen and/or accessory cells could be replaced by a monoclonal antibody to the CD3 determinant of human T cells (OKT3) bound to the surface of plastic tissue culture wells. Autoreactive, alloreactive, and antigen-reactive T cell lines and clones were maintained in culture for 8-12 weeks without antigen or accessory cells. The antigen specificity of these T cells was maintained. 相似文献
89.
The effect of ovarian steroids on epithelial ciliary beat frequency in the human Fallopian tube 总被引:3,自引:3,他引:3
Mahmood T; Saridogan E; Smutna S; Habib AM; Djahanbakhch O 《Human reproduction (Oxford, England)》1998,13(11):2991-2994
Using a method that detects variations in light intensity we have studied
the effect of ovarian steroids on human Fallopian tube epithelial ciliary
beat frequency in vitro. We have found that baseline ciliary beat frequency
averages between 5-6 Hz. Cilia from ampullary segments of the Fallopian
tube beat significantly faster (5.4 Hz+/-0.2) than those from fimbrial
segments (4.8 Hz+/-0.2). There was no significant difference in baseline
ciliary beat frequency at any other anatomical site in the Fallopian tube.
Incubation with progesterone (10 micromol/l) suppresses human Fallopian
tube epithelial ciliary beat frequency by 40-50%. This inhibition was
observed at similar magnitudes in all Fallopian tubes studied irrespective
of anatomical site. Progesterone-induced reductions in ciliary beat
frequency were concentration dependent and prevented by the progesterone
receptor antagonist mifepristone (RU486). Oestradiol alone (10 micromol/l)
had no effect on ciliary beat frequency at any anatomical site in the
Fallopian tube but did prevent the reduction in ciliary beat frequency seen
with progesterone when tissues were incubated with these two steroids
together.
相似文献
90.
Bacterial Clearance and Cytokine Profiles in a Murine Model of Postsurgical Nosocomial Pneumonia 下载免费PDF全文
Patricia A. Manderscheid Ryan P. Bodkin Bruce A. Davidson Erik Jensen Thomas A. Russo Paul R. Knight 《Clinical and Vaccine Immunology : CVI》2004,11(4):742-751
The development of a nosocomial pneumonia is facilitated by alterations in host innate pulmonary antibacterial defenses following surgical trauma, which can result in decreased pulmonary bacterial clearance and increased morbidity and mortality. In a murine model of postoperative nosocomial infection, surgical stress (laparotomy) decreased Escherichia coli clearance from the lungs of animals that underwent surgery. Consistent with previous studies, (i) pulmonary levels of tumor necrosis factor alpha at 6 h and of interleukin-1β (IL-1β), IL-6, and gamma interferon (IFN-γ) at 24 h post-bacterial infection (PBI) were decreased in animals that underwent laparotomy 24 h prior to E. coli infection (LAP/E. coli) compared to animals that received E. coli only; (ii) KC and macrophage inhibitory protein 2 were elevated at 6 h PBI in LAP/E. coli animals compared to E. coli-only animals; however, at 24 h PBI, levels were higher in the E. coli-only group; (iii) at 24 h PBI, monocyte chemoattractant protein 1 was lower in the LAP/E. coli group compared to the E. coli-only group; (iv) IL-10 levels were unaffected at all time points evaluated; and (v) the total number of neutrophils present in the lungs of LAP/E. coli animals at 6 h PBI was decreased in comparison to that in E. coli-only animals, resulting in decreased bacterial clearance and increased mortality in LAP/E. coli animals by 24 h PBI. Similar changes in cytokine profiles, pulmonary bacterial clearance, and mortality were consistent with reported findings in patients following surgical trauma. This model, therefore, provides a clinically relevant system in which the molecular and cellular mechanisms that lead to the development of nosocomial pneumonia can be further explored. 相似文献