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An unusual retinal manifestation of arteriovenous communications is reported in a case showing a combination of Sturge-Weber and Kippel-Trenaunay syndromes. The arteriovenous communications are thought to be similar to those seen in the limbs in Parkes-Weber syndrome. This retinal finding indicates that the three syndromes are intricately related to each other and may be an incomplete manifestation of a single pathophysiologic entity which may be named neurocutaneous angiomatosis.  相似文献   
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Cardiovascular diseases (CVD) among non-communicable diseases are already a major public health challenge worldwide. A further increase in CVD is projected to occur over the next 25 years as a result of both adverse lifestyle changes and demographic shifts in the population age profile. The adverse impact of these health problems will affect women in particular, given the steady rise in the proportion of the aging population that will be women.The critical issue presently in the management of CVD is that we are not even adequately using the data that are available. Women still remain unaware that they are at risk, and information about women is not easily accessible to their physicians. This is a global issue and the need remains for worldwide initiatives with greater vigilance to identify these factors and make efforts to control them effectively.Currently, in scientific research, it is expected that the results of clinical research be analyzed for sex differences, sex- and gender-appropriateness, and sex- and gender-specific approaches for prevention, diagnosis, treatment, and counseling. To address the care discrepancy, the global community needs to develop a conducive environment within a comprehensive policy and operational framework to achieve favorable lifestyles, and CVD risk factor reduction for both men and women.  相似文献   
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The role of biomarkers in disease prognosis continues to be an important investigation in many cancer studies. In order for these biomarkers to have practical application in clinical decision making regarding patient treatment and follow-up, it is common to dichotomize patients into those with low vs. high expression levels. In this study, receiver operating characteristic (ROC) curves, area under the curve (AUC) of the ROC, sensitivity, specificity, as well as likelihood ratios were calculated to determine levels of growth factor biomarkers that best differentiate lung cancer cases versus control subjects. Selected cut-off points for p185erbB-2 and EGFR membrane appear to have good discriminating power to differentiate control tissues versus uninvolved tissues from patients with lung cancer (AUC = 89% and 90%, respectively); while AUC increased to at least 90% for selected cut-off points for p185erbB-2 membrane, EGFR membrane, and FASE when comparing between control versus carcinoma tissues from lung cancer cases. Using data from control subjects compared to patients with lung cancer, we presented a simple and intuitive approach to determine dichotomized levels of biomarkers and validated the value of these biomarkers as surrogate endpoints for cancer outcome.  相似文献   
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The recent discovery of cat fleas (Ctenocephalides felis) infected with a typhuslike rickettsia (designated the ELB agent) raises the question of whether similar rickettsial infections exist in wild cat flea populations. We verified the presence of the ELB agent and Rickettsia typhi in urban and suburban areas of Los Angeles, Calif. Opossums trapped in close proximity to the residences of human murine typhus cases in Los Angeles county and other areas within the city of Los Angeles were tested for the presence of typhus group rickettsiae by the polymerase chain reaction (PCR). The presence of rickettsiae in the spleen tissues of three opossums (n = 9) and in 66 opossum fleas (n = 205) was determined by PCR and was verified by dot blot and Southern transfer hybridization. Further analysis of the amplified PCR products generated by a series of primer pairs derived from either the 17-kDa antigen gene or the citrate synthase gene revealed that both R. typhi and the ELB agent were present in the tested samples. Dual infection was not noted in the samples; however, the fleas were infected with either R. typhi or the ELB agent. The presence of the ELB agent in the cat flea population may have implications for public health. Whether this agent is responsible for the mild cases of human murine typhus in urban and suburban areas of Los Angeles or in other endemic foci remains to be determined.  相似文献   
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The existence of intracellular rickettsiae requires entry, survival, and replication in the eukaryotic host cells and exit to initiate new infection. While endothelial cells are the preferred target cells for most pathogenic rickettsiae, infection of monocytes/macrophages may also contribute to the establishment of rickettsial infection and resulting pathogenesis. We initiated studies to characterize macrophage-Rickettsia akari and -Rickettsia typhi interactions and to determine how rickettsiae survive within phagocytic cells. Flow cytometry, microscopic analysis, and LDH release demonstrated that R. akari and R. typhi caused negligible cytotoxicity in mouse peritoneal macrophages as well as in macrophage-like cell line, P388D1. Host cells responded to rickettsial infection with increased secretion of proinflammatory cytokines such as interleukin-1beta (IL-1beta) and IL-6. Furthermore, macrophage infection with R. akari and R. typhi resulted in differential synthesis and expression of IL-beta and IL-6, which may correlate with the existence of biological differences among these two closely related bacteria. In contrast, levels of gamma interferon (IFN-gamma), IL-10, and IL-12 in supernatants of infected P388D1 cells and mouse peritoneal macrophages did not change significantly during the course of infection and remained below the enzyme-linked immunosorbent assay cytokine detection limits. In addition, differential expression of cytokines was observed between R. akari- and R. typhi-infected macrophages, which may correlate with the biological differences among these closely related bacteria.  相似文献   
8.
The host response to bites of the oriental rat flea, Xenopyslla cheopis Rothschild, was investigated by examining rat blood leucocyte kinetics, histopathology, and the effect that the host response had upon subsequent flea feeding and longevity. Test rats were subjected to controlled exposures of fleas, and leucocyte data from test rats were compared to those of unexposed controls. Of the five leucocyte types examined, only the basophil appeared to play a role in the host blood response to flea bites. Significant increases in blood basophil levels occurred 2-3 d after exposure but subsided to control levels within a week. However, flea feeding did not produce histopathology at the flea feeding sites nor did the basophilic blood response of rats affect subsequent feeding or longevity of the fleas.  相似文献   
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BACKGROUND: Dengue is a major public health problem in several countries. Few reports document presentations and outcomes of dengue during pregnancy. In many endemic countries as the average age of getting dengue infections is shifting upwards, dengue in pregnancy is likely to be encountered more frequently. Patterns of dengue in patients from different regions are needed if we are to draft evidence based management guidelines. OBJECTIVES: To document clinical and laboratory findings in a cohort of hospitalised patients with dengue during pregnancy in Sri Lanka and compare their presentation and outcomes with previously published cases. STUDY DESIGN: Clinical, laboratory, maternal and fetal outcomes and demographic information were collected from patients with confirmed dengue infections during pregnancy treated in a Maternity Hospital in Sri Lanka from 1 January 2000 to 30 June 2004. The Medline database was searched to identify reports relating to dengue infection during pregnancy since 1965. RESULTS: Twenty-six patients [mean (S.D.) age: 29 (4.2) years] were studied. One (3.8%), 2 (7.7%) and 20 (77%) presented in the first, second and third trimesters of pregnancy, and 3 (11.5%) in the immediate post-partum period. Seventeen (65.3%) had primary and nine (34.7%) secondary dengue infections. Ten (38.5%) had DF, 6 (23.1%): DHF grade I and 10 (38.5%): DHF grade II. Five (19.2%) and three (11.5%) patients who first presented with cough/breathlessness or vaginal bleeding, were initially managed as having a pulmonary embolism or a primary obstetric cause for their vaginal bleeding. Bradycardia was noted in three of the four patients who had a cardiac arrhythmia. Seven (26.9%) needed admission to an ICU. Raised AST and ALT levels were seen in 81.2% and 43.7% of 16 patients in whom liver function tests results were available. No fetal malformations were seen in any of the babies born. The single patient who developed DHF in the first trimester had an abortion while having acute symptoms of dengue. CONCLUSIONS: Awareness of clinical and laboratory manifestations of dengue in pregnancy should allow its early recognition and institution of appropriate treatment. Reports on dengue in pregnancy from different regions should allow more evidence-based guidelines to be formulated for optimum evaluation and care of such patients. Our data contributes towards this goal.  相似文献   
10.
The contribution of the λ-light chain to the development of peripheral B cell repertoire and generation of specific antibodies to haptens and polysaccharide antigens was studied in genetically manipulated kappa-deficient and λ2-transgenic mice. The results clearly demonstrate a non-stoichiometric VH gene family expression in the absence of k-light chain and suggest a non-stochastic pairing between VH and Vλ genes, expressed in the peripheral B cell repertoire. A shift in VH gene utilization in the case of Vlλ+ antibodies was evident in response to β2–6 fructosan and TNP hapten. These observations demonstrate the availability of compensatory mechanisms in the absence of VK genes and are consistent with the hypothesis that VH gene family expression is controlled by genetic factors from inside the VH locus. Furthermore, genetic factors from outside the VH locus, namely restricted available light chain diversity, may lead to a shift in VH gene utilization in the peripheral B cell repertoire.  相似文献   
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