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991.
992.
ObjectiveTo retrospectively investigate cesarean scar pregnancy (CSP) patients who received systemic methotrexate (MTX) and to clarify the criteria for administering systemic MTX to CSP patients.Materials and methodsFifteen CSP patients who were initially treated with systemic MTX (50 mg/m2/week) were included. Nine patients, who needed a uterine artery embolization (UAE) or a laparotomy, including a transabdominal hysterectomy (TAH), were defined as the unsuccessful MTX group. Six patients who did not require UAE or a laparotomy were defined as the successful MTX group. Furthermore, the hCG cut-off value and the GS cut-off size at the time of CSP diagnosis, which differentiated successful and unsuccessful patients, were defined. MTX success rates were investigated by combining the hCG and gestational sac (GS) size cut-off values.ResultsThe hCG cut-off value was 17757.0 mIU/mL, and the GS cut-off size was 10.4 mm. In patients with hCG values less than 17757.0 mIU/mL, the MTX success rate was 75.0%. Fewer patients needed UAE or a laparotomy compared to patients with hCG values higher than 17757.0 mIU/mL (P = 0.007). In patients with a GS size less than 10.4 mm, the MTX success rate was 80.0%. Fewer patients among them needed UAE or a laparotomy compared to those among patients with a GS size greater than 10.4 mm (P = 0.089). In patients with hCG values and GS sizes lower than the cut-off values, the MTX success rate was 80.0%. Fewer patients among them needed UAE or a laparotomy compared to those among patients with hCG values and/or GS sizes higher than the cut-off values, respectively (P = 0.010).ConclusionPatients with hCG values less than 17757.0 mIU/mL and GS sizes less than 10.4 mm may have a greater chance of successful systemic MTX treatment when it is used as the first line of treatment for CSP.  相似文献   
993.

Purpose:

To quantitatively and noninvasively assess neurological disease progression in a mouse model of Niemann‐Pick type C (NPC) disease by measuring white matter status with magnetic resonance imaging (MRI) techniques of T2 mapping and diffusion tensor imaging (DTI).

Materials and Methods:

Quantitative T2 and DTI experiments were performed in vivo in NPC disease model and control mice at three timepoints to quantify differences and changes in white matter with measurements of T2 relaxation and DTI parameters. Histological staining for myelin content was also performed at two timepoints to compare with the MRI findings.

Results:

The results of the T2 and DTI measurements show significant differences in white matter areas of the brain in the NPC disease model compared to control mice at several timepoints, and were seen to change over time in both groups.

Conclusion:

The findings of this study suggest that quantitative MRI measurements may be suitable in vivo biomarkers of disease status for future studies of NPC disease models. The changes in white matter measurements between timepoints in both control and NPC disease groups suggest that white matter structures continue to change and develop over time in the NPC model and can be tracked with MRI techniques. J. Magn. Reson. Imaging 2012;35:528‐536. © 2011 Wiley Periodicals, Inc.  相似文献   
994.
995.
Follicular T‐cell lymphoma (FTCL) is considered to originate from follicular helper T‐cell (Tfh) cells. Angioimmunoblastic T‐cell lymphoma (AITL) and peripheral T‐cell lymphomas with the Tfh phenotype, derived from Tfh cells, often harbor RHOA G17V mutation. We investigated whether RHOA mutations affect the clinicopathological features of FTCL. We performed deep sequencing and Sanger sequencing for RHOA exon 2 in 16 cases of FTCL. Nine cases showed RHOA mutations, including eight with c.G50T, p.Gly17Val and one with c.G50A, p.Gly17Glu, c.A52G, p.Lys18Glu, c.T102C, p.Tyr34Tyr and c.G145T, p.Asp49Tyr. Compared to the RHOA mutation‐negative group, the RHOA mutation‐positive group had a higher tendency for B‐immunoblasts (P = 0.06), the AITL component (P = 0.09), and higher positive rate for CD10 (P = 0.09) and BCL6 (P = 0.09), and a significantly higher positive rate for CXCL13 (P = 0.04). Although not statistically significant, the RHOA mutation‐positive group showed higher values for almost all characteristic AITL features. There was no significant difference in overall survival between RHOA mutation‐positive and ‐negative groups. The RHOA mutation may play an important role in clinicopathological characteristics and lymphomagenesis of FTCL. A more detailed investigation is needed to highlight the importance of RHOA mutations in FTCL.  相似文献   
996.
The simple sorting procedure and continuous use of poly(N-isopropylacrylamide) (PNIPAM), a well-known thermoresponsive polymer, have a high potential for the mass production of single-walled carbon nanotubes (SWCNTs) with a specific electronic structure. However, knowledge of efficient single-chirality sorting methods with mixed surfactant systems is not applicable. In this work, we explored experimental conditions by controlling the interaction among PNIPAM, sodium cholate (SC) and SWCNTs. An optimization of the PNIPAM and SC concentrations as well as the addition of sodium borate achieved the selective release of (6,4) nanotubes into the liquid phase after the PNIPAM phase transition. The sorting mechanism with PNIPAM was explained by the difference in the micelle configuration on the SWCNTs and the hydrophobic collapse of PNIPAM in the presence of a sodium salt. The one-step sorting procedure for obtaining SWCNTs with a single chirality via PNIPAM will help promote their widespread application.

Optimized experimental conditions in the presence of sodium borate achieved the selective release of (6,4) nanotubes into the liquid phase.  相似文献   
997.
998.
TRA98 is a rat monoclonal antibody (mAb) which recognizes a specific antigen in the nuclei of germ cells. mAb TRA98 has been used to understand the mechanism of germ cell development and differentiation in many studies. In mice, the antigen recognized by mAb TRA98 or GCNA1 has been reported to be a GCNA gene product, but despite the demonstration of the immunoreactivity of this mAb in human testis and sperm in 1997, the antigen in humans remains unknown, as of date. To identify the human antigen recognized by mAb TRA98, a human comprehensive wet protein array was developed containing 19,446 proteins derived from human cDNAs. Using this array, it was found that the antigen of mAb TRA98 is not a GCNA gene product, but nuclear factor-κB activating protein (NKAP). In mice, mAb TRA98 recognized both the GCNA gene product and NKAP. Furthermore, conditional knockout of Nkap in mice revealed a phenotype of Sertoli cell-only syndrome. Although NKAP is a ubiquitously expressed protein, NKAP recognized by mAb TRA98 in mouse testis was SUMOylated. These results suggest that NKAP undergoes modifications, such as SUMOylation in the testis, and plays an important role in spermatogenesis.  相似文献   
999.
1000.
Infection with Shiga toxin (Stx)-producing Escherichia coli (STEC) is a serious public health concern, causing severe diarrhea and hemolytic-uremic syndrome. Patient symptoms are varied among STEC strains, possibly implying the presence of markers for STEC virulence other than Stx. To reveal the genotypic traits responsible for STEC virulence, we investigated 282 strains of various serogroups for the presence of 17 major virulence genes, i.e., stx1, stx2a, stx2c, stx2d, stx2e, stx2f, eae, tir, espB, espD, iha, saa, subA, ehxA, espP, katP, and stcE. Next, we examined the prevalence of virulence genes according to the seropathotypes in which serotypes were classified (seropathotypes A through E) based on the reported frequencies in human illness, as well as known associations with outbreaks and with severe disease. Our results demonstrate that the presence of both katP and stcE in STEC, in addition to the genes located in the locus of enterocyte effacement (LEE), including eae, tir, espB, and espD, may indicate the most pathogenic genotype of STEC. A population structure analysis of the profiles of virulence genes statistically supported the pathogenic genotype and, furthermore, revealed that there are serogroups with potentially higher pathogenicity than previously thought. Some strains in serogroups O26, O145, and O165 may have high virulence equivalent to that of serogroup O157. Several serogroups, including O14, O16, O45, O63, O74, 119, O128, and O untypeable, also may be potentially pathogenic, although rarely in humans.  相似文献   
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