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991.
BACKGROUND: Antibody responses to pneumococcal conjugate vaccines may vary when administered in different populations or epidemiologic settings. Understanding the causes and significance of this variation could help to determine the number of doses and timing required for protection against pneumococcal diseases in each country. METHODS: This report compares antibody responses to aluminum-adjuvanted and nonadjuvanted mixed carrier 11-valent diphtheria- or tetanus-conjugated pneumococcal vaccine (11-PncTD) formulations when given at 6, 10 and 14 weeks and 9 months of age to Filipino infants (n = 51) and at 2, 4, 6 and 12 months of age to Finnish (n = 127) and Israeli (n = 124) infants. The study populations differ in their natural exposure to pneumococcus and risk factors for pneumococcal carriage and disease. RESULTS: Filipino and Israeli infants had slightly but significantly higher prevaccination geometric mean concentration (GMC) of antibodies than did the Finnish infants. After three doses of aluminum-adjuvanted 11-PncTD vaccine, the Filipino infants had 1.8 to 6.7 and 1.5 to 5.0 times higher GMC than the Finnish and Israeli infants, respectively, against pneumococcal serotypes conjugated to tetanus protein. The GMC of serotypes conjugated to diphtheria toxoid was 1.3 to 3.0 and 0.7 to 2.0 times the GMC in Finnish and Israeli infants, respectively. The nonadjuvanted vaccine formulation induced generally lower GMCs. CONCLUSIONS: The antibody responses to the tetanus-conjugated polysaccharides were considerably higher in the Filipino than in the Finnish or Israeli infants. This may be a result of several factors including the priming effect of tetanus toxoid given to pregnant women, early pneumococcal nasopharyngeal acquisition and genetic differences among populations.  相似文献   
992.
993.
Regenerative processes enhance postsynaptic potential (PSP) amplitude and behaviorally relevant temporal filtering in more than one-third of electrosensory neurons in the torus semicircularis of Eigenmannia. Data from in vivo current-clamp intracellular recordings indicate that these "regenerative PSPs" can be divided in two groups based on their half-amplitude durations: constant duration (CD) and variable duration (VD) PSPs. CD PSPs have half-amplitude durations of between 20 and 60 ms that do not vary in relation to stimulus periodicity. In contrast, the half-amplitude durations of VD PSPs vary in relation to stimulus periodicity and range from approximately 10 to 500 ms. Injection of 0.1 nA sinusoidal current through the recording electrode demonstrated that CD PSPs and not VD PSPs can be elicited by voltage fluctuations alone. In addition, CD PSPs were blocked by intracellular application of either QX-314 or QX-222, whereas VD PSPs were not. These in vivo data suggest, therefore, that CD PSPs are mediated by voltage-dependent Na+ conductances.  相似文献   
994.
While the androgens, including dihydrotestosterone (DHT), have been implicated in the development of androgenetic alopecia (AGA), the exact mechanism by which they exert their effect(s) is unknown. Since apoptosis is an integral component of the normal cycling of human hair, we investigated individuals clinically affected by AGA to assess whether objective differences in the expression of apoptosis-related immunohistochemical markers could be observed in scalp biopsies. Specimens from 16 alopecic male patients were stained with bd-2 and the terminal deoxynucleotidyltransferase dUTP fluorescein nick end-labeling (TUNEL) method was used to assess apoptotic activity in affected and unaffected areas ofthe scalp. Immunoreactivity was analyzed by quantifying staining differences within the same individual. Sections from 3 human volunteers were used to establish the method validity. Significant differences in the bcl-2 staining index (0.67 versus 0.42, p < 0.05) and TUNEL expression (5.7 versus 10.2, p < 0.05) were observed between the areas of the scalp that were clinically affected (frontal) and unaffected (occipital) by AGA. The Gaussian distributions of bcl-2 and TUNEL staining suggest that a relatively uniform population of follicles exists at the frontal hairline and/or that synchrony of follicular cycling occurs in AGA. The apoptosis "hot spot" revealed by TUNEL staining in the bulge-isthmus region of the murine follicle is also identifiable in the human follicle.  相似文献   
995.
996.
997.
Two de novo cases with Apert Syndrome detected prenatally are presented herein. In the first, fetal ultrasound findings of syndactyly of the hands, craniosynostosis and proptosis resulted in a prenatal diagnosis in the nineteenth week of gestation. This is the earliest prenatal diagnosis of this syndrome in a not-at-risk case. Following counseling, this pregnancy was terminated and subsequent pathological examination and DNA analysis confirmed the diagnosis of Apert Syndrome and coarctation of the aorta. In the second case, fetal ultrasound at 21 weeks' gestation revealed a hypoplastic left heart and clover-leaf skull. Following counseling, this pregnancy was also terminated. Further examination of the fetus and DNA analysis led to a diagnosis of Apert Syndrome. These cases emphasize the need to complete a thorough fetal ultrasound in cases with potentially lethal cardiac abnormality and the importance of incorporating a fetal pathologist, as well as a medical geneticist, in the investigations performed after delivery or pregnancy termination when a fetal abnormality is detected on ultrasound.  相似文献   
998.
A rapid 'one-plate' in vitro test for pyrogens   总被引:2,自引:0,他引:2  
A rapid, 'one-plate' monocyte-activation test is described for detecting endotoxin and non-endotoxin pyrogens in parenteral medicinal products. The one-plate test offers useful gains over conventional 'two-plate' (cell culture plate+ELISA plate) tests in terms of its limit of detection, robustness, speed and cost. The 'one-plate' test is likely to be applicable to a wide range of products because it allows less time for product interference in the test. The 'one-plate' test utilises pyrogen-free anti-cytokine (interleukin (IL)-6 or tumour necrosis factor alpha (TNFalpha)) antibodies (Ab), coated and stabilised onto (pyrogen-free) 96-well plates. Monocytes/monocytic cells, endotoxin (lipopolysaccharides, LPS) standard or sample and (pyrogen-free) second (labelled) Ab are cultured together (usually for 2-4 h) on the Ab-coated plate and then the plate is washed and the ELISA completed. There is no transfer from one plate to another and no (further) incubations of (released) cytokine with, first, coating Ab and, then, developing Ab since these steps have already taken place during the initial cell culture. The rapid, 'one-plate' test is readily automated. The preferred readout is IL-6, which gives a limit of detection of 0.015 endotoxin units (EU)/ml with peripheral blood mononuclear cell (PBMNC), 0.03 EU/ml with diluted whole blood and 0.05 EU/ml with a monocytic cell line (MONO MAC 6).  相似文献   
999.
1000.
Ovarian cancer remains the most deadly gynecologic malignancy, resulting in an estimated 23,300 new cases and 13,900 deaths in the United States in the year 2002. The discovery of the BRCA1 gene in 1994 has proven to be of great interest to the study of hereditary ovarian cancer. BRCA1 gene mutation confers a 16-42% lifetime risk of the development of ovarian cancer in those affected. Although BRCA1 functions as a tumor suppressor gene, conflicting studies have shown that BRCA1 dysfunction alone may not be sufficient for tumorigenesis. p53 is a tumor suppressor gene found to be dysfunctional in nearly 50% of all human cancers and in up to 80% of ovarian malignancies. The p53 protein product plays a crucial role in DNA surveillance and repair at the Gap 1-synthesis (G1-S) cell cycle checkpoint. Studies exhibiting the interaction of BRCA1 and p53 and the role of this interaction in DNA damage response led many investigators to suggest that p53 gene mutation is required for BRCA1-associated tumor development. This review explores the evidence for BRCA1 and p53 interplay, and outlines the crucial role p53 may play in BRCA1-related ovarian cancer.  相似文献   
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