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41.
The proinflammatory cytokine tumor necrosis factor (TNF)-alpha has been shown to facilitate leukocyte transendothelial migration. In multiple myeloma, TNF-alpha is an important factor in the promotion of growth and survival of the malignant cells. Studies have shown that enhanced TNF-alpha levels in myeloma patients correlated with aggressive disease. Therefore, we investigated the effect of recombinant human TNF-alpha on the migrational behavior of myeloma cells across the physiological barrier of the major disease compartment, i.e., human bone marrow endothelial cells. In the presence of TNF-alpha, we observed significantly increased migration both in established myeloma cell lines and in plasma cells from myeloma patients. Expression of TNF-receptor 2 (TNF-R2) but not TNF-receptor 1 (TNF-R1) was detected in myeloma cell lines. Myeloma cells of patients also showed expression of TNF-R2 but not TNF-R1. The effect of TNF-alpha could not be explained by altered expression of adhesion molecules or metalloproteases. Instead, we found an up-regulation of monocyte chemoattractant protein (MCP)-1 and confirmed that myeloma cells express the relevant receptor C-C chemokine receptor 2. Preincubation of myeloma cells with recombinant human MCP-1 also enhanced cell migration, and this effect, as well as the effect of TNF-alpha, was abolished by treatment with anti-MCP-1 antibody. In contrast, migration of myeloma cells in the direction of an MCP-1 gradient, i.e., chemotaxis, could not be observed in the cell lines investigated. Additionally, the mRNA level of TNF-alpha was up-regulated by the cytokine treatment, which points to an autocrine loop augmenting and/or stabilizing the TNF-alpha-MCP-1 pathway. In summary, our data clearly support additional investigations using anti-MCP-1 antibodies in myeloma progression.  相似文献   
42.
Melanoma inhibitory activity (MIA) is an 11-kDa secretory protein isolated from malignant melanoma cells that is correlated with invasion and metastasis in various human malignancies. We examined MIA expression in 62 oral squamous cell carcinomas (OSCC) by immunohistochemistry. MIA expression was significantly associated with nodal metastasis ( P =  0.00018). MIA expression was also associated with expression of high mobility group box-1 (HMGB1) ( P <  0.0001) and lymph vessel density ( P <  0.0001). Expression levels of MIA, HMGB1, nuclear factor kB (NFkB) p65 and HMGB1–NFkB p65 binding were significantly higher in a metastatic human OSCC cell line (HSC3) than those in a non-metastatic OSCC cell line (HSC4). Treatment with receptor for advanced glycation end products (RAGE) antisense or small interfering RNA and human recombinant HMGB1 (hrHMGB1) did not affect MIA expression, whereas HMGB1 antisense or siRNA treatment decreased MIA expression in HSC3 cells. Then HMGB1 enhanced MIA expression as an NFkB cofactor but not as a RAGE ligand. MIA neutralization by MIA antibodies increased extracellular signal-related kinase 1/2 phosphorylation, but decreased p38 phosphorylation and the expression of vascular epithelial growth factor (VEGF)-C and -D. Treatment with p38 inihibitor decreased VEGF-C and -D expression in HSC3 cells. These results suggest that MIA expression is enhanced by the interaction of intracellular HMGB1 and NFkBp65 and MIA is closely involved in tumor progression and nodal metastasis by the increments of VEGF-C and VEGF-D in OSCC. ( Cancer Sci 2008; 99: 1806– 1812)  相似文献   
43.
Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120, 1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320, respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections. Received: 10 April 2000 / Accepted: 18 July 2000  相似文献   
44.
We tested the level of protection provided by the Rispens CVI988 (Rispens) vaccine against challenge with a virulent Marek's disease virus (MDV) pathotype (vMDV) and a very virulent pathotype (vvMDV) and the accuracy of a range of predictive measures of Marek's disease (MD) incidence and vaccine take. Commercial layer chicks (n?=?236) were vaccinated (or not) with 4000?plaque-forming units (pfu) of Rispens vaccine at hatch and challenged (or not) with 500?pfu of each challenge virus five days post vaccination. The vvMDV pathotype FT158 induced higher MD incidence (65%) and mortality (33%) when compared with the vMDV pathotype MPF57 (39% and 8%, respectively). The protective index provided by the Rispens vaccine against FT158 (61%) did not differ significantly from that against MPF57 (66%). This provides additional evidence that protection provided by the Rispens vaccine is not influenced by pathotype determined in studies using vaccines of other Mardivirus species. The challenge viruses did not differ in MDV or Rispens viral load in spleen at 14?dpc (days post challenge) determined by specific quantitative polymerase chain reaction test. MDV load in peripheral blood leucocytes at 7 and 14?dpc, splenocytes at 14?dpc, feather cells at 14 and 21?dpc and isolator dust at 21?dpc were significant early indicators of subsequent MD incidence to 56?dpc. These are potentially useful as the sampling can be carried out well before the onset of MD and some measures are non-invasive. The Rispens viral load in both invasive and non-invasive samples was more useful as a measure of vaccine take.  相似文献   
45.

Study Objective

Uterine transplantation has proven feasible since the first live birth reported in 2014. To enable attachment of the uterus in the recipient, long vascular pedicles of the uterine and internal iliac vessels were obtained during donor hysterectomy, which required a prolonged laparotomy to the living donors. To assist further attempts at uterine transplantation, our video serves to review literature reports of internal iliac vein anatomy and demonstrate a laparoscopic dissection of cadaver pelvic vascular anatomy.

Design

Observational (Canadian Task Force Classification III).

Setting

Academic anatomic laboratory. Institutional Review Board ruled that approval was not required for this study.

Intervention

Literature review and laparoscopic dissection of cadaveric pelvic vasculature, focusing on the internal iliac vein.

Measurements and Main Results

Although the internal iliac artery tends to have minimal anatomic variation, its counterpart, the internal iliac vein, shows much variation in published studies 1, 2. Relative to the internal iliac artery, the vein can lie medially or laterally. Normal anatomy is defined as some by meeting 2 criteria: bilateral common iliac vein formed by ipsilateral external and internal iliac vein at a low position and bilateral common iliac vein joining to form a right-sided inferior vena cava [2]. Reports show 79.1% of people have normal internal iliac vein anatomy by these criteria [2]. The cadaver dissection revealed internal iliac vein anatomy meeting criteria for normal anatomy.

Conclusion

Understanding the complexity and variations of internal iliac vein anatomy can assist future trials of uterine transplantation.  相似文献   
46.
The amplitude of otoacoustic emissions (OAE) is known to decrease with increasing age, but it is still unclear whether this is due to aging alone or to age-related hearing loss. This study describes the exploration of a large database (5,142 patients from 0.4 to 89.8 years) collected in a routine clinical testing. Reliable pure tone audiograms, transitory evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE) recordings were available from 5,424 ears without conductive loss, acute sudden deafness or retrocochlear disorder. From this database, group 1 with behavioral thresholds of 10 dB HL or better at all frequencies from 1 to 4 kHz and group 2 with age-accordant thresholds after ISO 7029 were formed. In both groups, the OAE amplitude decreased with increasing age, but in group 1, the effect was significant only for DPOAE recorded at 3 and 4 kHz. In group 2, the loss of amplitude was steeper and highly significant for TEOAE as well as DPOAE at all frequencies, but most pronounced at high frequencies. These findings support the hypothesis that the reduction of OAE amplitude with increasing age is primarily caused by age-linked hearing loss and not by aging alone.  相似文献   
47.
The Arrhenius parameters of the propagation rate coefficient, kp, are determined via the pulsed laser polymerization—size exclusion chromatography (PLP‐SEC) method for five branched acrylates (tert‐butyl (tBA), isobornyl (iBoA), benzyl (BnA), 2‐ethylhexyl (EHA), and 2‐propylheptyl acrylate (PHA)) in 1 m solution in butyl acetate (BuAc) to complete the series, published by Haehnel et al. in 2014, of branched acrylates (isononyl (INA‐A), tridecyl (TDA‐A and TDN‐A), heptadecyl (C17A), and henicosyl acrylate (C21A)) in solution that do not show a trend in kp. Furthermore, the propagation rate coefficients of the branched acrylates in 1 m solution are critically compared with the branched acrylates in bulk as well as branched methacrylates. A summary of the trends and family‐type behavior for the linear and branched (meth)acrylates as well as methacrylates with cyclic ester side chains is provided. For the branched acrylates in 1 m solution, no clear trends of the propagation rate coefficients, kp, or Arrhenius parameters A and EA are detectable and—in contrast to the corresponding methacrylates—there is no family‐type behavior observed in solution as well as in bulk.

  相似文献   

48.
49.
In accordance with simulation theories of empathy, the somatosensory cortex is involved in the perception of pain of others. Cognitive processes, like perspective taking, can alter empathy‐related activity within the somatosensory cortex. The current study investigates whether this modulation is caused by the imagined sensation of pain or by the cognitive load of a perspective‐taking task. Applying a within‐subject design, participants (N = 30) watched pictures of painful and nonpainful actions, while imagining reduced, normal, or increased pain perception of the observed individual. Mu activity (8–13 Hz), which is inversely correlated with sensorimotor‐cortex activity, was measured via EEG. To calculate mu activity (central electrodes) and alpha activity (occipital electrodes), which served as a control for effects of cognitive load, a fast Fourier transform was applied. Mu suppression linearly increased from reduced to normal to increased imagined pain (p < .05), while alpha activity was unaffected by the imagined pain (p > .80). Suppression of the 8–13 Hz band at central and occipital electrodes was stronger in response to painful actions compared to nonpainful actions (p < .01). These results indicate that modulation of mu activity through perspective taking reflects the imagined pain intensity and not the cognitive load induced by the task.  相似文献   
50.
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