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101.
102.
The expression of p120ctn protein in breast cancer is independent of alpha- and beta-catenin and E-cadherin. 总被引:3,自引:1,他引:3 下载免费PDF全文
D. A. Dillon T. D'Aquila A. B. Reynolds E. R. Fearon D. L. Rimm 《The American journal of pathology》1998,152(1):75-82
Several studies have reported loss or alteration of expression of E-cadherin in breast cancer and more recently changes in levels of expression of the catenins. We used immunofluorescence to examine E-cadherin, alpha-catenin, beta-catenin, and p120ctn (formerly p120CAS) expression in 91 cases of invasive ductal carcinoma. As expected, all four proteins co-localize to the junctional regions of the cells. Although nuclear localization has been described for beta-catenin in colonic polyps, no examples were found in these breast cancer cases. We found that, although alteration is common in the catenins and E-cadherin, complete loss, as exemplified by E-cadherin in lobular carcinoma (where E-cadherin is frequently mutated), is rarely seen. In contrast, the catenin-related protein p120ctn shows an expression pattern that is significantly unrelated to the other catenins (or E-cadherin), including complete loss of expression in approximately 10% of the cases. No statistically significant correlations with traditional prognostic indicators were observed with any of these proteins. We conclude 1) that expression of E-cadherin and alpha- and beta-catenin are generally retained at the membrane although frequently reduced or altered, 2) that complete loss of p120ctn expression is seen in approximately 10% of the cases, and 3) that there is a significant correlation in the expression of E-cadherin and the catenins but no correlation between these molecules and p120ctn, suggesting an absence of coordinate regulation. 相似文献
103.
T. I. Farag S. A. Al-Awadi S. A. Al-Othman T. S. Sundareshan D. S. Krishna Murthy R. Usha S. A. Mady R. Uma James F. Reynolds 《American journal of medical genetics. Part A》1988,29(4):943-944
Direct chromosome preparations of neonatal cord blood provides the unique opportunity for rapid chromosome analysis (turnaround time; 6 hr), without the necessity of bone marrow aspiration. Based on 42 samples we confirm the finding of Garnham and Sutherland [1987] for suitability of cord blood for direct chromosome preparation. Procedural modifications are provided for higher yield of cells for chromosome analysis. The procedure may well be of major significance for rapid diagnosis of neonates who suffer from aneusomy. 相似文献
104.
JS Pooni Dr DWL Hukins PF Harris RC Hilton KE Davies 《Surgical and radiologic anatomy : SRA》1986,8(3):175-182
Posterior and anterior heights, cross-sectional area and shape were measured for all the intervertebral discs in four spines from elderly human cadavers. Disc height was a minimum at the T4-5 level; thoracic discs were less wedge-shaped than those in the cervical and lumbar regions. Cross-sectional area increased from the cranial to caudal extremity; at the L5-S1 level the nucleus pulposus occupied a high proportion of this area. Cervical discs tended to have an elliptical cross-sectional shape, thoracic discs were more circular and lumbar discs tended to have an elliptical cross-section which was flattened or re-entrant posteriorly. This shape distribution was quantified by defining a shape index which had a maximum value of 1 for a circular cross-section. Orientations of the reinforcing fibres in the outer lamellae of the anterior annulus fibrosus were measured from 27 discs by X-ray diffraction. For these measurements, C3-4, T7-8 and L2-3 were chosen as representative of cervical, thoracic and lumbar discs. The fibre tilt, with respect to the axis of the spine, was significantly less in the cervical discs (at 65 degrees) than in the thoracic and lumbar discs (about 70 degrees). These findings are interpreted in relation to differing functional requirements and possible mechanisms of failure in the cervical, thoracic and lumbar regions of the spine in the light of current knowledge on the biomechanics of the intervertebral disc. 相似文献
105.
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine. 相似文献
106.
Alteration of pulmonary neuroendocrine cells during epithelial repair of naphthalene-induced airway injury 下载免费PDF全文
Peake JL Reynolds SD Stripp BR Stephens KE Pinkerton KE 《The American journal of pathology》2000,156(1):279-286
Whole-mount airway preparations isolated from the lungs of mice treated by intraperitoneal injection of naphthalene and allowed to recover for 5 days were examined for the distribution and abundance of solitary pulmonary neuroendocrine cells (PNECs) and neuroepithelial bodies (NEBs) along the main axial pathway of the right middle lobe. Sham mice treated with corn oil vehicle were examined in a similar manner. An antibody to calcitonin gene-related peptide, a neuroendocrine cell marker, was used to identify the location, size, and number of PNECs and NEBs in the airways. After naphthalene treatment and epithelial repair, NEBs were significantly increased along the walls of the airways as well as on branch point ridges. The surface area covered by NEBs composed of 20 or fewer PNECs was significantly enlarged after naphthalene treatment compared with control NEBs of an equivalent cell number. The PNEC number per square millimeter was also increased more than threefold above control values after naphthalene treatment. These findings provide further support for a key role of neuroendocrine cells in the reparative process of airway epithelial cell renewal after injury. 相似文献
107.
Preliminary report of an ultrasonography and colour Doppler uterine score to predict uterine receptivity in an in-vitro fertilization programme 总被引:1,自引:4,他引:1
Salle B; Bied-Damon V; Benchaib M; Desperes S; Gaucherand P; Rudigoz RC 《Human reproduction (Oxford, England)》1998,13(6):1669-1673
A total of 96 women undergoing in-vitro fertilization (IVF) treatment were
examined by transvaginal ultrasonography with colour and pulsed Doppler
ultrasound on the 22nd day of the menstrual cycle preceding IVF. We
assessed endometrial thickness, endometrial morphology, myometrial
echogenicity, subendometrial vascularization, the uterine artery
pulsatility index, protodiastolic notch and end diastolic blood flow in
order to define a uterine score which could be correlated with the
pregnancy rate. The overall pregnancy rate was 30.2%, and there was no
difference between the pregnant and non-pregnant groups with regard to any
of the ultrasonographic and Doppler parameters when examined separately.
However, the uterine score was significantly higher in the pregnant group
(15.9 +/- 2.81 versus 12.7 +/- 5.3, P = 0.002; t-test). No pregnancy
occurred if the score was between 0 and 10. With a score of 11-15 there was
a 34.7% chance of pregnancy, and scores >16 had a 42% chance of
pregnancy. In conclusion, individual ultrasonographic and Doppler
parameters are not of sufficient accuracy to predict uterine receptivity.
The uterine score calculated prior to IVF cycles appears to be a useful
predictor of implantation.
相似文献
108.
109.
Efferent lymph from nodes regional to areas of skin that had been treated with solutions of oxazolone in acetone was collected from unanaesthetized sheep. The application of 5% solutions of oxazolone to unsensitized sheep caused no signs of acute inflammation or ''shut-down'' of lymphocyte traffic; none the less, normal immune responses ensued so that immunoblasts, some containing immunoglobulin, were discharged into the lymph together with specific humoral antibodies. When previously sensitized sheep were challenged with 2.5% solutions of oxazolone the vigorous secondary responses were heralded by Arthus reactions, induced presumably by pre-existing antibodies, which were mainly of the IgG class. A similar sequence of events occurred in a thymus-deprived sheep which had undergone intra-uterine thymectomy at 60 days of gestation. Repeated applications of oxazolone to normal sheep did not exhaust or inhibit the characteristic changes in the flow and composition of the lymph. When immunoblasts from efferent lymph were radiolabeled with 125I-UdR and returned intravenously to the sheep they showed no significant tendency to localize either specifically or non-specifically in areas of skin that had been treated with contact-sensitizing chemicals. 相似文献
110.
Three judges were trained to evaluate the frequency, intensity, and duration of aggressive responses in rats. Intrajudge and interjudge reliability ranged from .84 to .99. Correlation coefficients between frequency, intensity, and duration of aggressive responses ranged from .89 to .99. All three measures were found to be highly reliable methods of measuring aggression. 相似文献