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William B. Kannel MD Ramachandran S. Vasan MD 《Current cardiovascular risk reports》2007,1(3):204-208
Low diastolic blood pressure is alleged to impose excess cardiovascular disease (CVD) risk in patients with treated hypertension,
impeding aggressive reduction of blood pressure. Most investigations that assessed the potential J-shaped relations of diastolic
blood pressure and adverse outcomes have not adequately considered systolic or pulse pressure in statistical analyses. An
overview of hypertension trials indicates that lowering elevated blood pressure reduces the risk of CVD outcomes irrespective
of the associated decrease in diastolic pressure, even if the achieved diastolic pressure averages less than 70 mm Hg. The
Framingham study investigations have determined that the increased CVD incidence observed at low diastolic blood pressure
levels is confined largely to persons with concomitantly increased systolic pressure. This finding of no true excess risk
at low diastolic blood pressure agrees with the results of trials that have evaluated the J-curve phenomenon adjusting for
systolic pressure. Aggressively treating systolic hypertension appears to produce no cause for alarm. 相似文献
5.
Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator. 相似文献
6.
The antimutator phenotype, reportedly conferred by disruption of the Saccharomyces cerevisiae DDR48 gene, was suggested to affect only a specific spontaneous mutational pathway. We attempted to identify the types of mutation that are DDR48-dependent by determining the specificity of the ddr48 antimutator. However, disruption of DDR48 did not decrease the rates of spontaneous forward mutation in a plasmid-borne copy of the yeast SUP4-o gene, the reversion or suppression of the lys2–1 allele, or forward mutation at the CAN1 locus. Interestingly, the latter gene had been reported previously to be subject to the antimutator effect. DNA sequence analysis of spontaneous SUP4-o mutations arising in DDR48 and ddr48 backgrounds provided no evidence for a reduction in the rates of individual mutational classes. Thus, we were unable to verify that disruption of DDR48 causes an antimutator phenotype. 相似文献
7.
During the first half of the 20th century, chronic energy undernutrition due to low dietary intake, repeated infections, and rapid succession of pregnancy were the factors most responsible for maternal undernutrition and consequent adverse outcomes of pregnancy. Efforts to improve dietary intake, treatment of infections, and provision of contraceptive care were the major focuses of intervention from 1950 to 1990. These interventions resulted in reduction in severe grades of undernutrition. However, there was no reduction in mild and moderate degrees of undernutrition and anemia during pregnancy and there was no significant improvement in the course and outcome of pregnancy, or in birth weight. During the 1990s, among the middle- and upper-income groups, there has been a progressive rise in obesity and consequent adverse effects. The advent of HIV infection in India in the 1980s will inevitably lead to increases in severe undernutrition associated with HIV infection in pregnancy and an adverse impact of maternal HIV infection on the fetus. Practicing physicians and nutritionists in the new millennium will therefore have to assess each person individually and provide appropriate advice regarding diet, exercise, fertility, and infection prevention and control in order to achieve optimum health and nutrition status during pregnancy and to prevent adverse pregnancy outcomes. 相似文献
8.
Bipolar affective disorder. II. EEG, neuropsychological, and clinical correlates of CT abnormality 总被引:1,自引:0,他引:1
M J Dewan C V Haldipur M F Boucher T Ramachandran L F Major 《Acta psychiatrica Scandinavica》1988,77(6):677-682
Since the clinical significance of CT abnormalities found in bipolar patients remains obscure, we studied 26 DSM-III bipolar patients who had specific CT abnormalities (third ventricle enlargement, and hyperdensity of the caudate, thalamus, anterior frontal white matter, and right temporal lobe) on numerous parameters such as EEG, the Halstead-Reitan Neuropsychological Battery, premorbid personality adjustment, family history of affective disorder, positive and negative symptoms, employment history, and response to lithium carbonate treatment. None of these measures could differentiate between the CT abnormal and CT normal subgroups. The implications of these findings are discussed. 相似文献
9.
F W Symington B E Symington P Y Liu H Viguet U Santhanam P B Sehgal 《Transplantation》1992,54(3):457-462
The potential involvement of cytokines in acute graft-versus-host disease led us to analyze interleukin-6 in serial serum sets from 22 allogeneic marrow recipients who developed either grade 3 or 4 GVHD (n = 10), grade 2 GVHD (n = 6), or grade 1 or no diagnosed GVHD (n = 6). A total of 279 serial serum samples taken three times weekly before day 35 were analyzed. Maximum IL-6 levels were greater than 40 U/ml (range, 40-1536 U/ml), 11-40 U/ml, and less than or equal to 10 U/ml for six, eleven, and five patients, respectively. Serum IL-6 peaks were temporally related to onset of GVHD, onset of a syndrome of hepatorenal dysfunction (HRD), or bilateral lung infiltration. Eight of ten patients who developed grade 3 or 4 GVHD overall had IL-6 maxima of greater than 10 U/ml an average of 1.5 +/- 1.8 days before the clinical onset. Fifteen of 17 patients with peak IL-6 levels greater than 10 U/ml developed symptoms of hepatic and renal dysfunction within three days of the peak, while none of five patients with less than or equal to 10 U/ml of Il-6 developed HRD. Regression analysis demonstrated a linkage between the log magnitudes of the serum IL-6 peaks and onset of either GVHD or HRD within three days (P = 0.001). Furthermore, IL-6 peaks tended to precede GVHD onset for the 10 patients whose GVHD onset and IL-6 peak were within three days of each other (P = 0.02). These results, confirmed by both specific bioassay and by IL-6 ELISA, support the idea that acute GVHD in humans involves a cytokine cascade that includes production of IL-6 in addition to the previously reported involvement of tumor necrosis factor alpha and interferon-gamma. 相似文献
10.
Madanagopalan Ethunandan David W Macpherson Vijay Santhanam 《Journal of oral and maxillofacial surgery》2007,65(12):2512-2517
PURPOSE: Systematic evaluation of the Karapandzic flap in the reconstruction of lip defects after ablative surgery. PATIENTS AND METHODS: Patients who had a Karapandzic flap to reconstruct lip defects were analyzed with reference to demographic details, histology and location of the tumor, and dimensions of resection. The functional aspects of the reconstruction were assessed in terms of the size of the oral stoma, preservation of oral competence, and facial expression, in addition to speech, diet and ease of cutlery, and denture usage. The esthetic outcome was assessed with a 4-point scale and in addition the symmetry of the commissure at rest and function, preservation of the philtrum, and lip projection also were assessed. The complications were noted. RESULTS: Seven patients underwent Karapandzic flap reconstruction (4 males, 3 females) with an age range of 43 to 98 years. Three tumors were located in the upper lip, 4 in the lower lip, and there were 5 squamous and 2 basal cell carcinomas. The lip defects ranged from 40% to 75% of the lip circumference. The oral stoma was of a reduced circumference in all cases but did not lead to any functional compromise in terms of oral competence, facial expression, speech, diet, denture and cutlery usage, and sensation. There were no wound complications in our series. The esthetic outcome was considered excellent/good in 85% of cases. The commissure was symmetrical in all except 1 patient, the philtrum was preserved in all cases of lower lip reconstruction, and the projection of the lip was reduced in edentulous patients. CONCLUSIONS: The Karapandzic flap is a reliable technique that offers consistently good functional and esthetic outcomes after reconstruction of lip defects. 相似文献