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81.
To investigate the chronologic change of mother-to-child transmission of human T lymphotropic virus type I (HTLV-I) in Okinawa, Japan, the presence of antibody to HTLV-I was tested in 4,187 healthy residents between, 4,528 nursery school children, and 3,837 pregnant women between 1968 and 2000. The chronologic change of the feeding method and the length of the breast-feeding period among 1,117 healthy mothers from 1937 to 1995 were also obtained by interview. Age-adjusted prevalence of HTLV-I among healthy residents decreased from 9.1% in 1968-1970 to 7.8% in 1981-1984 and to 6.3% in 1996-1998. The crude prevalence of antibody to HTLV-I among healthy residents less than 20 years old decreased significantly from 4.6% in 1968-1970 to 0.1% in 1996-1998 (P < 0.0001). The prevalence of antibody to HTLV-I among nursery school children decreased significantly over the study period, from a high of 1.8% in 1984 to a low of 0.2% in 1998 (P = 0.03). The prevalence among pregnant women decreased significantly from 5.6% in 1989-1992 to 3.7% in 1997-2000 (P = 0.0275). Prior to 1967, all healthy mothers breast-fed their children. After 1968, the use of bottled and mixed milk (breast milk and bottled milk) increased, with bottled milk becoming predominant after 1990 (89%). The percentage of healthy mothers breast-feeding for more than one year significantly decreased from 68.3% in 1937-1947 to 0.4% in 1990-1995 (P < 0.0001). Infection with HTLV-I in Okinawa has decreased mainly due to a reduction in the number of mothers breast-feeding and a shortening of the breast-feeding period. However, because the mother-to-child transmission rate among non-breast-feeders decreased from 12.8% in 1986-1991 to 3.2% in 1995-1999, there may be other factors involved in the decrease in mother-to-child transmission.  相似文献   
82.
BACKGROUND/AIMS: Aberrations of the pRb (Retinoblastoma gene protein)-p16INK4 pathway play a critical role in carcinogenesis. Our objective is to evaluate its role in tumorigenesis and the development of ampullary cancer. METHODOLOGY: We examined expression status of p16INK4 protein and pRb immunohistochemically and assessed their possible prognostic relevance in 36 ampullary cancers. RESULTS: Thirty-four specimens (94.4%) exhibited alteration of p16INK4 and/or pRb expression, with 63.9% (23/36) of cancers showing p16INK4 negative expression and 94.4% (34/36) pRb abnormal expression. p16INK4 protein negative expression correlated significantly with tumor progression features such as advanced tumor stages (p=0.0291), lymph node metastasis (p=0.005), pancreas invasion (p=0.0002) and duodenum invasion (p=0.0101). Cases with both p16RNK4 protein negative expression and pRb overexpression showed poorer differentiation, more invasive growth (p=0.0425), higher level tumor stages (p=0.0079) and more frequent pancreas invasion (p=0.0024), compared with the others. p16INK4 protein expression showed no relationship with pRb expression (p=0.2199). No association was found in pRb expression status compared with any clinicopathological parameters analyzed. CONCLUSIONS: The disruption of the pRb-p16NK4 pathway plays an important role in ampullary carcinogenesis, the absence of p16INK4 protein expression might be involved in ampullary tumor progression.  相似文献   
83.
84.
Graft tunnel placement is the factor with most influence on the outcome of double-bundle anterior cruciate ligament (ACL) reconstruction. However the final decision for the graft location has to be decided subjectively under arthroscopy, and can be misplaced due to the effect of the knee flexion angle. The displacement of the estimated placement by surgeons from the ACL anatomical attachment is due to the knee’s differing knee flexion angle. Eight cadaveric knees and an electromagnetic position recording system were employed. After digitizing the anatomical location of AM and PL bundle center, four experienced surgeons estimated the graft placement repeatedly at 70°, 90° and 110° of knee flexion. The displacements between these two positions were calculated and analyzed separately in antero-posterior and disto-proximal directions. The displacements of the estimated AM bundle placements were 4.7 ± 3.4 mm at 70°, 4.3 ± 2.2 mm at 90°, and 6.0 ± 2.6 mm at 110°, while those of the PL bundle were 4.0 ± 2.2 mm at 70°, 3.4 ± 1.9 mm at 90°, and 4.2 ± 2.5 mm at 110°. The best results were obtained at 90° of knee flexion. Additionally, the estimated placements for both AM and PL bundle were located more distally as the flexion angle increased. Our results imply that the knee should be set at 90° when determining the graft placement in double-bundle reconstruction to prevent misplacement of the graft usually in a disto-proximal direction.  相似文献   
85.
Ito D  Suzuki N 《Neurology》2011,77(17):1636-1643
The RNA-binding proteins TAR DNA-binding protein (TDP-43) and fused in sarcoma (FUS) play central roles in neurodegeneration associated with familial amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). Normally localized in the nucleus, in sites affected by ALS and FTLD-U they are mislocalized to the cytoplasm and form cytoplasmic inclusions. TDP-43 and FUS are transported to the nucleus in a Ran-GTPase-dependent manner via nuclear import receptors, but they also contribute to the formation of stress granules (SGs), which are intracytoplasmic structures incorporating RNA. C-terminal truncations of TDP-43 eliminate the nuclear transport signal and cause mislocalization of the protein to the cytoplasm, where it accumulates and forms SGs. ALS-associated FUS mutations impair nuclear transport and cause mislocalization of FUS to the cytoplasm, where it also contributes to assembly of SGs. Furthermore, the ALS susceptibility factor ataxin-2, recently identified as a potent modifier of TDP-43 toxicity, is also a predicted cytoplasmic RNA-binding protein and a constituent protein of SGs, suggesting that it is a part of the common pathologic cascade formed by TDP-43 and FUS. Thus, we propose that excessive mislocalization of the RNA-binding proteins TDP-43, FUS, and ataxin-2 into the cytoplasm leads to impairment of the RNA quality control system, forming the core of the ALS/FTLD-U degenerative cascade. In this review, we discuss the molecular basis of the novel disease spectrum of ALS/FTLD-U, including the neurodegenerative mechanism of the cytoplasmic RNA-binding proteins TDP-43 and FUS and the possibility of a novel therapeutic strategy.  相似文献   
86.
87.
By recalling gustatory memories, it is possible to generate vivid gustatory perceptions in the absence of gustatory inputs. This gustatory image influences our gustatory processing. However, the mechanism of the "top-down" modulation of gustatory perception in the human is still unclear. Our findings propose a new perspective on the neural basis of gustatory processing. Although gustatory imagery and gustatory perception shared common parts of neural substrates, there was an asymmetrical topography of activation in the insula: the left insula was predominantly activated by gustatory imagery tasks. In addition, the middle and superior frontal gyri were not activated by gustatory perception but they participated in the generation of gustatory hallucinations. These regions in the frontal cortex may mediate the "top-down" control of retrieving gustatory information from the storage of long-term memories.  相似文献   
88.
Neuronal cell death accounts for the clinical manifestations in Alzheimer's disease (AD). To establish the curative therapy of AD, neuroprotection is one of the primary therapeutic targets, and the elucidation of the mechanism of neuronal cell death is mandatory. Detailed characterization of neuronal cell death caused by familial AD (FAD)-linked mutant genes revealed that different cell death pathways are evoked by different types of mutants. Humanin (HN), a newly identified neuroprotective peptide, suppresses neuronal cell death caused by all known FAD mutants and A beta, while it has no effect on neuronal cell death caused by AD-irrelevant insults. The functional target of HN is the antagonism to neuronal death, not the modulation of A beta production, suggesting that HN-based medication can be combined with other remedies targeting A beta. HN is a promising seed for a novel therapy aiming at complete cure of AD through the suppression of neuronal loss.  相似文献   
89.
Background: We developed a surgical knee rest (SKR) that can be used to decrease the stress placed on the lower half of the body when surgeons work in the standing position. We tested the effectiveness of this device in the context of laparoscopic surgery.

Material and methods: Five healthy, right-handed male surgeons participated, and we recorded surface electromyography (sEMG) signals from the two heads of the left and right gastrocnemius (Gc) muscles during laparoscopic resections of colorectal cancer. The outcome variable was the percentage of maximum Gc muscle effort generated, reported as percent maximal isometric voluntary contraction (%MVC), and this variable was compared between surgeries performed with and without use of the SKR. Assessment covered the first 100?min of surgery, subdivided into two 50-min periods.

Results: Mean %MVC of the left Gc muscle for the full 100-min test period was significantly decreased when the SKR was used (p?=?.027, vs. SKR not used). Notably, mean %MVC of both Gc muscles was significantly decreased during the first 50?min of surgery (p?=?.008 and p?=?.0046).

Conclusion: The SKR is useful for decreasing physical stress incurred by laparoscopic surgeons when working in the standing position.  相似文献   

90.

Background  

An early virological response (EVR) after the start of interferon (IFN) treatment for chronic hepatitis C leads to a successful virological outcome. To analyze an association between sustained virological response (SVR) and EVR by comparing TaqMan with Amplicor assays in HCV genotype 1-infected patients treated with pegylated (PEG)-IFN alpha-2b plus ribavirin (RBV).  相似文献   
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