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71.
The tomographic localization of activity within human primary visual cortex (striate cortex or V1) was examined using whole-head magnetoencephalography (MEG) and 4-T functional magnetic resonance imaging (fMRI) in four subjects. Circular checkerboard pattern stimuli with radii from 1.8 to 5.2 degrees were presented at eccentricity of 8 degrees and angular position of 45 degrees in the lower quadrant of the visual field to excite the dorsal part of V1 which is distant from the V1/V2 border and from the fundus of the calcarine sulcus. Both fMRI and MEG identified spatially well-overlapped activity within the targeted area in each subject. For MEG, in three subjects a very precise activation in V1 was identified at 42 ms for at least one of the two larger stimulus sizes (radii 4.5 and 5.2 degrees ). When this V1 activity was present, it marked the beginning of a weak wave of excitations in striate and extrastriate areas which ended at 50 ms (M50). The beginning of the next wave of activations (M70) was also marked by a brief V1 activation, mainly between 50 and 60 ms. The mean separation between V1 activation centers identified by fMRI and the earliest MEG activation was 3-5 mm.  相似文献   
72.
This study aimed to assess the effectiveness of an interprofessional education model (IPE) based on the transtheoretical model to improve the participants’ interprofessional collaborative practice. The study was conducted in Iran using a controlled before-and-after study design. The participants (n = 91) were the residents of emergency medicine and nurses of the emergency units from two teaching hospitals affiliated to Iran University of Medical Sciences. The participants in the intervention group (n = 40) were 22 residents and 18 nurses. The control group (n = 51) consisted of 20 residents and 31 nurses. The participants were classified based on their stage of readiness to change. The interventions were two-day workshops for each stage (i.e., attitude and intention). We used the Interprofessional Collaborator Assessment Rubric (ICAR) to assess the effectiveness of the developed model. The interprofessional collaboration of the participants in the intervention and control groups was assessed at four time points before and after the intervention in the real emergency unit environment. Student’s t-test and repeated measures analysis of variance (RM-ANOVA) were used to analyse the data. We used partial eta-squared (η2) for effect size calculations. The mean values of ICAR scores in the intervention and control groups were 95.63 ± 19.14 and 89.19 ± 16.11 before the intervention. The mean values of ICAR scores at 3 months after the intervention were 99.82 ± 22.32 and 88.29 ± 16.87 in the intervention and control groups, respectively. After 6 months, the mean values of ICAR scores of the intervention and control groups were 98.6 ± 23.40 and 87.98 ± 16.01, respectively. The results showed that the intervention had a medium educational effect size (partial η2 = 0.06) on performance of the participants. Our results showed that an IPE model that is tailored to the learners’ stage of readiness to change improves interprofessional collaboration in the participants. The developed model could be applied for improving interprofessional collaborative performance in other IPE programmes.  相似文献   
73.
One of the most common and unwanted side effects during oral anticoagulant therapy (OAT) is bleeding complications. In rare cases, vitamin K antagonist (VKA)-related bleeding events are associated with mutations affecting the F9 propeptide at amino acid position 37 due to a substitution of alanine to either valine or threonine. Based on our actual cohort of 18 patients, we update the knowledge on this rare phenotype and its origin. A founder mutation for both variants was reconfirmed by haplotype analysis of intronic and extragenic short tandem repeat (STR) polymorphisms with a higher prevalence in Switzerland than in other regions of Europe. Screening of healthy individuals for the presence of these F9 gene mutations did not identify any of these variants, thus proving the rare occurrence of this genotype. Furthermore, both variants were expressed in vitro and warfarin dose responses were studied. Our warfarin dose response analysis confirmed higher sensitivity of both variants to warfarin with the effect being more apparent for Ala37Thr. Thus, although F9 propeptide mutation-associated hypersensitivity to VKA is a rare phenomenon, awareness towards this bleeding phenotype is important to identify patients at risk.  相似文献   
74.

Microalbuminuria is a sensitive marker to detect early nephropathy in diabetes mellitus. Cystatin C correlates better than serum creatinine with microalbuminuria in type 1 diabetes mellitus (T1D). We evaluated the correlation between microalbuminuria, serum cystatin C (Cyc-C), and serum creatinine (SCr) in diabetic children. A hundred patients with stable T1D and 66 sex-matched healthy children were entered in the study between September 2008 and February 2011. Fasting blood sample was drawn for HbA1C, creatinine, and cystatin C. A. 24-h urine aliquot was collected to measure microalbumin, creatinine, and volume. Glomerular filtration rate estimated based on creatinine (eGFRcr), cystatin C (eGFRCyst C), and creatinine + cystatin C (eGFRCyst C + Cr). Binary logistic regression analysis, chi-square, ANOVA, Student’s t test, and nonparametric median tests were used to analyze data. P < 0.05 was considered significant. Medians serum creatinine and cystatin C of T1D group were significantly different from controls (P < 0.05). Overall, medians eGFRCyst C were higher than eGFRcr, or eGFRCyst C + Cr. Thirty-six children with T1D had microalbuminuria. There was a correlation between microalbuminuria and eGFRCyst C (<60 and >130 ml/min/1.73 m2) (P < 0.05). Medians eGFRcr were significantly lower than medians eGFRCyst C in T1D, regardless of microalbuminuria (P < 0.05). Chronic kidney disease classification according to eGFRcr and eGFRCyst C were not matched (P < 0.05). GFR in healthy children was overestimated by eGFRCyst C and underestimated by eGFRcr. There was higher correlation between abnormal eGFRCyst C and microalbuminuria in diabetic children. eGFRCr detected higher rate of GFR less than 60 ml/min/1.73 m2.

  相似文献   
75.
Background

Peri-implant diseases have been recognized as being among the ever-increasing complications related to dental implants. The aim of this study was to evaluate the adjunctive use of enamel matrix derivative (EMD) to mechanical debridement (MD) in patients with these conditions in terms of clinical parameters and cytokine levels of peri-implant crevicular fluid (PICF).

Methods

In the present double-blind clinical trial, 46 patients with peri-implant mucositis (PM) were randomly divided into control and test groups. Two different therapeutic protocols, consisting of non-surgical MD alone (control group) and MD with the application of EMD (test group), were considered for the two groups. Clinical parameters [bleeding on probing (BOP) and probing depth (PD)] and sampling from PICF were carried out before treatment and 3 months postoperatively. The levels of IL-6 and IL-17 cytokines in PICF were evaluated by enzyme-linked immunosorbent (ELISA).

Results

Three-month post-interventional assay revealed significant improvements in BOP and PD in the test group in comparison to the control group (P < 0.0001). Relative to control, IL-6 and IL-17 levels were reduced significantly (p < 0.05) in the test group compared to the control group.

Conclusion

Application of EMD can be considered an adjunct to MD in the non-surgical treatment of PM. However, complete recovery was not observed using either treatment approach showing that management of implant-associated disease is still a significant clinical problem.

  相似文献   
76.
Iranian johnsongrass mosaic virus (IJMV) is one of the most prevalent viruses causing maize mosaic disease in Iran. An IJMV isolate, Maz-Bah, was obtained from the maize showing mosaic symptoms in Mazandaran, north of Iran. The complete genomic sequence of Maz-Bah is 9544 nucleotides, excluding the poly(A) tail. It contains one single open reading frame of 9165 nucleotides and encodes a large polyprotein of 3054 amino acids, flanked by a 5′-untranslated region (UTR) of 143 nucleotides and a 3′-UTR of 236 nucleotides. The entire genomic sequence of Maz-Bah isolate shares identities of 84.9 and 94.2 % with the IJMV (Shz) isolate, the lone complete genome sequence available in the GenBank at the nucleotide (nt) and deduced amino acid (aa) levels, respectively. The whole genome sequences share identities of 51.5–69.8 and 44.9–74.3 % with those of other Sugarcane mosaic virus (SCMV) subgroup potyviruses at nt and aa levels, respectively. In phylogenetic trees based on the multiple alignments of the entire nt and aa sequences, IJMV isolates formed a separate sublineage of the tree with potyviruses infecting monocotyledons of cereals, indicating that IJMV is a member of SCMV subgroup of potyviruses. IJMV is most closely related to Sorghum mosaic virus and Maize dwarf mosaic virus and less closely related to the Johnsongrass mosaic virus and Cocksfoot streak virus. To further investigate the genetic relationship of IJMV, 9 other isolates from different hosts were cloned and sequenced. The identity of IJMV CP nt and aa sequences of 11 Iranian isolates ranged from 86.4 to 99.8 % and 90.5 to 99.7 %, respectively, indicating a high nt variability in CP gene. Furthermore, in the CP-based phylogenetic tree, IJMV isolates were clustered together with a maize potyvirus described as Zea mosaic virus from Israel (with 86–89 % nt identity), indicating that both isolates probably are the strains of the same virus.  相似文献   
77.
It is still controversial which cell types are responsible for synovial inflammation in osteoarthritic (OA) joints. The aim of this study was to quantify the mononuclear cell populations and their cytokines in patients with different knee OA subtypes. Synovial membrane (SM), synovial fluid (SF) and peripheral blood (PB) were harvested from patients with unicompartmental (UC) and bicompartmental (BC) knee OA. Frequencies of mononuclear cells were assessed by flow cytometry in PB and SM. Naive SF samples were analysed for a broad variety of cytokines by multiplex analysis. SM of both groups displayed a distinct mononuclear cell infiltration, with CD14+ macrophages being the major cell population, followed by CD4+ T cells and only small numbers of CD8+ T, CD19+ B and CD16+CD56+ natural killer (NK) cells. Between the two groups, SM of BC OA showed significantly higher amounts of mononuclear cells (135·7 ± 180 versus 805 ± 675 cells/mg, P = 0·0009) and higher CD4+ T cell presence (3·4 ± 4·6 versus 9·1 ± 7·5%, P = 0·0267). SF of BC OA displayed significantly higher concentrations for a number of proinflammatory cytokines [CXCL1, eotaxin, interferon (IFN)‐γ, interleukin (IL)‐7, IL‐8, IL‐9, IL‐12]. UC and BC OA show significant differences in their synovial inflammatory pattern. Whereas in UC OA CD14+ macrophages are the predominant cell population, BC OA has a higher inflammatory profile and seems to be driven by CD14+ macrophages and CD4+ T cells. Inclusion of clinical information into the analysis of cellular and molecular results is pivotal in understanding the pathophysiology of OA.  相似文献   
78.

Purpose

According to previous studies, vitamin D exhibits protective effects against breast cancer via the vitamin D receptor (VDR). There is growing evidence that breast cancer incidence is associated with various polymorphisms of the VDR gene. This study investigates the association of VDR poly(A) microsatellite variants with 25-hydroxyvitamin D (25(OH)D) serum levels and breast cancer risk.

Methods

Polymorphism analysis was performed on a total of 261 blood samples, which were collected from 134 women with breast cancer and 127 controls. Single strand conformation polymorphism was assessed by polymerase chain reaction in combination with sequencing to detect poly(A) lengths for each sample. The vitamin D levels of samples were determined by electrochemiluminescence.

Results

The poly(A) variant L allele frequency was significantly higher in cancer patients than in controls (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.16-2.57; p=0.006). Thus, carriers of the L allele (LS and LL genotypes) have a higher risk for breast cancer (OR, 1.86; 95% CI, 1.13-3.05; p=0.013). A larger increase in the risk for breast cancer was found in individuals with the L carrier genotype and lowered 25(OH)D levels.

Conclusion

The results primarily suggest that VDR gene polymorphism in the poly(A) microsatellite is associated with 25(OH)D levels and that it can affect the breast cancer risk in the female population from northern Iran.  相似文献   
79.

Background

Development of new natural agents for parasitic diseases treatment has unexpectedly increased to overcome effectively against emergence and re-emergence of parasitic diseases, the appearance of drug resistant organisms and toxic side effects of current agents. The aim of the study was to evaluate antiprotozoal activities of chitosan biomolecule on trophozoites of Trichomonas gallinae.

Methods

The antitrichomonal activity of various low molecular weight chitosan concentrations including 125, 250, 500 and 1250 µg ml−1 against T. gallinae trophozoites cultured in trypticase-yeast extract-maltose medium supplemented with heat-inactivated cold horse serum was evaluated in vitro. Samples containing medium without chitosan were also assayed as controls.

Results

The mortality rates at 0, 3 and 6 h post treatment with all concentrations were significantly different from control group (P<0.05). Treated trophozoites showed more susceptibility to the highest concentration reaching mortality rate of 100% at 3h post inoculation. However, at this time, results for 125, 250 and 500 µg ml−1 were 93%, 95% and 96.7%, respectively.

Conclusion

The results demonstrate that the application of chitosan biomolecule is a promising option for treatment of trichomoniasis in pigeons.  相似文献   
80.
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