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991.
A video colposcopy allows the real-time images viewed by the doctor performing the examination to be viewed by patients on a television monitor during the consultation. Eighty-one women (requiring either laser treatment or a normal recheck) were randomly assigned to either the video intervention group or the control group. A significant decrease in state anxiety was observed from one visit to the next in all patients (P = 0.000). This decrease in anxiety was significantly greater in the laser patients in the video colposcopy condition than patients in the control group for both groups of patients. Patients in the experimental groups also reported less pain than patients in the control conditions (P < 0.05). This benefit associated with video colposcopy was not observed on the second (treatment) visit. In conclusion, video colposcopy is a useful and time-efficient method that reduces patient anxiety and pain during examination visits, but not necessarily during visits where laser treatment is required.  相似文献   
992.
To assess whether the free-to-total prostate specific antigen (PSA) ratio (F/T PSA ratio) would enhance prostate cancer detection in Korean men with serum total PSA levels between 4 and 20 ng/ml. Methods: A total of 240 consecutive patients whose serum PSA levels were between 4 and 20 ng/ml were enrolled in this two-year study. All patients underwent ultrasound-guided transrectal biopsies of the prostate gland. The F/T PSA ratio was measured using the Roche immunoassay. Results: Of the 240 patients, 202 (84%) had benign histologies, while 38 (16%) had prostate cancer. The two patient groups were well matched for age. The mean F/T PSA ratio showed a statistically significant difference between the two groups: in the benign histology group it was 0.14 (0.04 - 0.37), and 0.10 (0.08 - 0.20) in the prostate cancer group (p < 0.05). Out of the 183 patients with a PSA level between 4-10 ng/ml, the mean F/T PSA ratios were 0.14 and 0.11 in the benign histology (n=158) and prostate cancer groups (n=25), respectively (p < 0.05). From the 57 patients with a PSA level between 10 - 20 ng/ml, the mean F/T PSA ratios were 0.14 and 0.10 in the benign histology (n=44) and prostate cancer groups (n=13), respectively (p < 0.05). Overall, when the cut-off value of the F/T PSA ratio was 0.10, the sensitivity and specificity were 75.0% and 76.5%, while for the cut-off value of 0.15 they were 83.3% and 39.7% respectively. Conclusion: Our data demonstrated the usefulness of the free to total PSA ratio in distinguishing benign prostate disease and cancer disease, hence eliminating unnecessary biopsies. It is recommended that a cut-off value for the F/T PSA ratio of 0.10 be applied to Korean men which this is lower than the value used in Western countries.  相似文献   
993.
Human immunodeficiency virus-type 1 (HIV-1) is a sexually transmitted pathogen that can infect cells in the female reproductive tract (FRT). The mechanism of viral transmission within the FRT and the mode of viral spread to the periphery are not well understood. To characterize the frequency of potential targets of HIV infection within the FRT, we performed a systematic study of the expression of HIV receptors (CD4, galactosyl ceramide (GalCer)) and coreceptors (CXCR4 and CCR5) on epithelial cells and leucocytes from the ectocervix. The ectocervix is a likely first site of contact with HIV-1 following heterosexual transmission, and expression of these receptors is likely to correlate with susceptibility to viral infection. We obtained ectocervical tissue specimens from women undergoing hysterectomy, and compared expression of these receptors among patients who were classified as being in the proliferative or secretory phases of their menstrual cycle at the time of hysterectomy, as well as from postmenopausal tissues. Epithelial cells from tissues at early and mid-proliferative stages of the menstrual cycle express CD4, although by late proliferative and secretory phases, CD4 expression was absent or weak. In contrast, GalCer expression was uniform in all stages of the menstrual cycle. CXCR4 expression was not detected on ectocervical epithelial cells and positive staining was only evident on individual leucocytes. In contrast, CCR5 expression was detected on ectocervical epithelial cells from tissues at all stages of the menstrual cycle. Overall, our results suggest that HIV infection of cells in the ectocervix could most likely occur through GalCer and CCR5. These findings are important to define potential targets of HIV-1 infection within the FRT, and for the future design of approaches to reduce the susceptibility of women to infection by HIV-1.  相似文献   
994.
The coelacanth is one of the nearest living relatives of tetrapods. However, a teleost species such as zebrafish or Fugu is typically used as the outgroup in current tetrapod comparative sequence analyses. Such studies are complicated by the fact that teleost genomes have undergone a whole-genome duplication event, as well as individual gene-duplication events. Here, we demonstrate the value of coelacanth genome sequence by complete sequencing and analysis of the protocadherin gene cluster of the Indonesian coelacanth, Latimeria menadoensis. We found that coelacanth has 49 protocadherin cluster genes organized in the same three ordered subclusters, alpha, beta, and gamma, as the 54 protocadherin cluster genes in human. In contrast, whole-genome and tandem duplications have generated two zebrafish protocadherin clusters comprised of at least 97 genes. Additionally, zebrafish protocadherins are far more prone to homogenizing gene conversion events than coelacanth protocadherins, suggesting that recombination- and duplication-driven plasticity may be a feature of teleost genomes. Our results indicate that coelacanth provides the ideal outgroup sequence against which tetrapod genomes can be measured. We therefore present L. menadoensis as a candidate for whole-genome sequencing.  相似文献   
995.
Formed almost exclusively during development, arterial elastic fibers must function for the lifetime of the animal. We have observed dramatic structural and mechanical changes in aortic elastic tissue during gestational and postnatal development. Elastic tissue was isolated from bovine aortas: (i) during late pregnancy and (ii) in adults. Changes in the relative content of aortic elastic tissue were assessed, as were the viscoelastic properties and residual strains of purified aortic elastic tissue rings. As aortic elastic tissue content increased during development, its circumference and thickness increased—but with circumference rising faster than wall thickness, causing a relative thinning of the elastic tissue. At the same time, elastic tissue stiffness increased while viscoelastic behavior decreased. Much of these changes were concentrated during late gestational development, such that the changes observed during the short span of late gestation examined (~60 days) were similar in magnitude to those occurring over the much longer postnatal period (~1–2 years). Finally, we observed an approximately threefold increase in residual strain in aortic elastic tissue from fetal to adult life, with most of this increase again occurring in late gestation. These results suggest that rapid remodeling, as well as accumulation, of aortic elastic tissue occurs during late gestation. These changes significantly alter both fetal aortic mechanical properties and residual stresses.  相似文献   
996.
We recently found that the antinociceptive effects produced by intrathecal administration of sildenafil, a phosphodiesterase 5 inhibitor, were reversed by a nonspecific adenosine receptor antagonist, suggesting that adenosine receptors are involved in sildenafil-induced antinociception. Four adenosine receptor subtypes have been identified: A1, A2A, A2B, and A3. We examined the involvement of spinal adenosine receptor subtypes in the antinociceptive effects of intrathecal sildenafil. Intrathecal catheters were implanted in male SD rats, and nociception was assessed using the formalin test, which consisted of a subcutaneous injection of 50 μl of 5% formalin solution into the hind paw. We examined the effects of an adenosine A1 receptor antagonist (CPT), an adenosine A2A receptor antagonist (CSC), an adenosine A2B receptor antagonist (alloxazine), and an adenosine A3 receptor antagonist (MRS 1220) on sildenafil-induced antinociception. Intrathecal sildenafil suppressed formalin-induced flinching during phases 1 and 2 of the test in a dose-dependent manner. Intrathecal CPT, CSC, alloxazine, and MRS 1220 all suppressed the antinociceptive effects of sildenafil during both phases of the formalin test. These results suggest that sildenafil is an effective treatment for acute pain and the facilitated pain state at the spinal level. Additionally, spinal adenosine A1, A2A, A2B, and A3 receptors may play a role in sildenafil-induced antinociception.  相似文献   
997.
Isolated cleft lip with or without cleft palate and cleft palate are among the most common human birth defects. Several candidate gene studies on MSX1 have shown significant association between markers in MSX1 and risk of oral clefts, and re-sequencing studies have identified multiple mutations in MSX1 in a small minority of cases, which may account for 1–2% of all isolated oral clefts cases. We explored the 2-Mb region around MSX1, using a marker map of 393 single nucleotide polymorphisms (SNPs) in 297 cleft lip, with or without cleft palate, case–parent trios and 84 cleft palate trios from Maryland, Taiwan, Singapore, and Korea. Both individual markers and haplotypes of two to five SNPs showed several regions yielding statistical evidence for linkage and disequilibrium. Two genes (STK32B and EVC) yielded consistent evidence from cleft lip, with or without cleft palate, trios in all four populations. These two genes plus EVC2 also yielded suggestive evidence for linkage and disequilibrium among cleft palate trios. This analysis suggests that several genes, not just MSX1, in this region may influence risk of oral clefts.  相似文献   
998.
Conclusion: The brief-smell identification test (B-SIT) can substitute for the butanol threshold test (BTT) in screening of anosmia and postoperative assessment of olfactory outcomes in patients with chronic rhinosinusitis (CRS). A time-effective test battery composed of B-SIT and the visual analog scale (VAS) can be implemented for simple olfactory assessment in any otolaryngology clinic. Objectives: Anosmia is a distinct clinical entity requiring special attention. Unpredictable olfactory outcomes after surgery make preoperative assessment more important. We compared the results of the BTT, B-SIT, and VAS to investigate whether B-SIT or VAS can substitute for BTT in screening of anosmia and postoperative follow-up. Methods: We collected data on 68 CRS patients who had bilateral CRS and underwent endoscopic sinus surgery. Olfactory performance was graded using the BTT: normosmia, hyposmia, or anosmia. VAS and B-SIT were also performed. All tests were repeated 6 months after surgery. Postoperative improvement was defined by an increase of the BTT score ≥ 2. Results: The B-SIT and VAS scores of the anomics were significantly lower than those of the normosmics. B-SIT discriminated anosmia with high specificity. Within the improvement group, postoperative increase of B-SIT/VAS score showed significance. However, neither the B-SIT nor the VAS differentiated between no change and deterioration of olfaction.  相似文献   
999.
1000.
The need for new anthelmintic with no chemical residues is becoming urgent. In a program aiming at the evaluation of plant as sources of new active molecules, the anthelmintic activities of the essential oils (EOs) obtained from either Zanthoxylum zanthoxyloides seeds or Newbouldia laevis leaves were evaluated against Strongyloides ratti by analyzing the results of two in vitro bioassays. These two plants and their tested parts were retained after an ethnopharmacology survey that confirmed their use by small-scale farmers for treatment of small ruminants affected by digestive helminths. The plants were harvested in Benin, and their EO were obtained by hydrodistillation. The EO yield of extraction was 0.65% (w/w) of for Z. zanthoxyloides seeds and 0.05% (w/w) for N. laevis. The chemical compositions of the two EOs were analyzed by gas chromatography coupled with mass spectrometry. The major constituents of the EO from Z. zanthoxyloides consisted of the following compounds: γ-terpinene (18 %), undecane (15 %), valencene (8.3 %), decanal (8.3 %), and 3-carene (6.7 %). In contrast, the major constituents of the EO from N. laevis leaves consisted of the following compounds: β-caryophyllene (36 %) and eugenol (5.8 %). An egg-hatching inhibition (EHI) assay was developed and a larval migration inhibition assay was used on S. ratti to examine the effects of the EOs and to evidence their inhibitory concentrations (IC50 and IC90) values on this nematode. Furthermore, the toxicity of the two EOs on Vero cell line was evaluated. When tested on S. ratti egg hatching, the two EOs resulted in similar IC50 values (19.5 and 18.2 μg/ml for Z. zanthoxyloides and N. laevis, respectively), which were about sevenfold higher than that of the control (thiabendazole, IC50 = 2.5 μg/ml). Larval migration was inhibited at similar concentrations for: Z. zanthoxyloides (IC50 = 46 μg/ml), N. laevis (IC50 = 51 μg/ml), and the control [levamisole (IC50 = 36 μg/ml)]. No cytotoxicity was found on Vero cells because both EOs had IC50 values higher than 50 μg/ml. Therefore, we have concluded that the EOs from two plants, used in folk medicine, may contain compounds with anthelmintic activity and could be used as improved traditional medicines or, at least, as food additives in a combined treatment for the control of helminth infections.  相似文献   
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