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Spermatozoa selection at high magnification before intracytoplasmic sperm injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development.  相似文献   
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OBJECTIVE: The objective was to develop an animal model using bacterial inoculation to evaluate tissue integration and tolerance to meshes used in genital prolapse surgery. STUDY DESIGN: We placed three different meshes under the abdominal skin of 120 Wistar rats: a polypropylene monofilament non-coated mesh (Parietene), a polypropylene monofilament collagen-coated mesh (Ugytex) and a polyethylene terephthalate mesh (Mersuture). We performed bacterial inoculation just after implantation with 1 ml of 10(7) colonies forming unit (CFU) of Staphylococcus epidermidis or Escherichia coli. Rats were sacrificed 7, 14, 60, and 90 days after intervention. We used polarised light microscopy to analyse the collagen deposition and organisation. We quantified the inflammation cells. Bacterial analysis and quantification of the explanted meshes were performed. The exact Fisher's test and Kruskal-Wallis test were used for statistics. RESULTS: We did not find any significant difference between inoculated or non-inoculated meshes in terms of collagen deposition. The scarring process seemed stable at day 90. Tissue integration was best with the polypropylene meshes, which allowed the development of a well-organised, mature connective tissue. Inflammatory reaction was higher in inoculated meshes, but only at day 7. At day 90, we found a high number of macrophages and multinuclear cells around all the meshes. There was no significant difference between prostheses that had been inoculated and those that had not with regard to positive bacterial culture. Quantification of bacterial colonies decreased with time. CONCLUSION: In this animal model, we did not find any clinically related difference in infection and tissue integration between the meshes used in genital prolapse. Such experimental studies must be carried out whenever new prostheses become available before their use is validated in common practice.  相似文献   
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We report two brothers, their mother and a maternal cousin who had a distinctive facial phenotype, mild brachydactyly and prominence of the interphalangeal joints. One brother and the mother also had multiple ventricular extrasystoles. Six other relatives in four generations were probably affected on the basis of history and family photographs. We also report a further individual from a different family with a similar facial phenotype, Pierre-Robin sequence, tapering fingers and multiple ventricular extrasystoles. These families have some similarities to those reported by Stoll et al. in a single family, showing dominant inheritance. Our patients would seem to have the same or a related condition.  相似文献   
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The purpose of this prospective randomized study was to evaluate use of a hyaluronan-rich transfer medium in fresh and frozen-thawed single blastocyst transfer. The study included 279 single blastocyst transfers in women aged<37 years in their first, second or third treatment cycle. According to the type of single blastocyst transfer (fresh elective or frozen-thawed) the women were divided into two study and two control groups. In both study groups (n=130) transfers were performed using hyaluronan and in the control groups (n=149) a conventional transfer medium was used. The results indicate that fresh elective single blastocyst transfer with hyaluronan results in significantly higher pregnancy rates in a selected subgroup of women; those with >or=2 blastocysts developed to day 5 and a previous implantation failure (55% versus 10%; P=0.012). Overall pregnancy rates after fresh elective and frozen-thawed single blastocyst transfer were similar in both study and control groups.  相似文献   
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BackgroundWomen are nearly twice as likely as men to suffer from major depressive disorder. Yet, there is a dearth of studies comparing the clinical outcomes of women and men with treatment-resistant depression (TRD) treated with similar augmentation strategies. We aimed to evaluate the effects of the augmentation strategies in women and men at the McGill University Health Center.MethodsWe reviewed health records of 76 patients (42 women, 34 men) with TRD, treated with augmentation strategies including antidepressants (AD) with mood stabilizers (AD+MS), antipsychotics (AD+AP), or in combination (AD+AP+MS). Clinical outcomes were determined by comparing changes on the 17-item Hamilton Depression Rating Scale (HAMD-17), Montgomery-Åsberg Depression Rating Scale (MADRS), Quick Inventory of Depressive Symptomatology (QIDS-C16), and Clinical Global Impression rating scale (CGI-S) at the beginning and after 3 months of an unchanged treatment. Changes in individual items of the HAMD-17 were also compared between the groups.ResultsWomen and men improved from beginning to 3 months on all scales (P < .001, η p2 ≥ 0.68). There was also a significant sex × time interaction for all scales (P < .05, η p2 ≥ 0.06), reflecting a greater improvement in women compared with men. Specifically, women exhibited greater improvement in early (P = .03, η p2 = 0.08) and middle-of-the-night insomnia (P = .01, η p2 = 0.09) as well as psychomotor retardation (P < .001 η p2 = 0.16) and psychic (P = .02, η p2 = 0.07) and somatic anxiety (P = .01, η p2 = 0.10).ConclusionsThe combination of AD+AP/MS generates a significantly greater clinical response in women compared with men with TRD, supporting the existence of distinct pharmacological profiles between sexes in our sample. Moreover, they emphasize the benefit of augmentation strategies in women, underscoring the benefit of addressing symptoms such as insomnia and anxiety with AP and MS.  相似文献   
90.
Spark Plasma Sintering (SPS) has become a conventional and promising sintering method for powder consolidation. This study aims to well understand the mechanisms of densification encountered during SPS treatments, especially in the early stages of sintering. The direct current (DC) electrical behavior of copper granular medium is characterized. Their properties are correlated with their microstructural evolutions through post-mortem scanning electron microscope (SEM) observations to allow a thorough understanding of the involved Branly effect that is suspected to occur in SPS. The electrical response is studied by modifying the initial thickness of the oxide layer on particles surfaces and applying various mechanical loads on the granular medium. Without load and at low current, the measured quasi-reversible behavior is connected to the formation of spots at the microcontacts between the particles. By increasing the current, the Branly transition from an insulating to a conductive state suddenly occurs. The insulating oxide layer is destroyed, and micro-bridges are created. The application of a mechanical pressure strongly modifies the DC Branly effect. Increasing low stress leads to a strong decrease in the breakdown field. For high-applied pressure, successive drops in the electric field are detected during the electrical transition. These successive drops are induced by microcracking of the insulating oxide layer.  相似文献   
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