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1.
The noxious effect of a single dose of 20 IU human chorionic gonadotropin (hCG) given at proestrus on embryonic and fetal survival as well as on fetal weight was studied. Fetal survival varied between 43.6 and 67.6%; the mortality rate was highest before implantation. The surviving fetuses of rats treated with hCG between days 17 and 20 of pregnancy weighed significantly less than controls. Embryonic mortality and fetal growth retardation could be prevented by giving anti-hCG monoclonals 28 or 45 h after hCG administration, but not when anti-hCG was given 69 or 93 h after hCG. 5 IU hCG did not induce embryonic or fetal mortality. On the other hand, 80 IU hCG increased the mortality to 100%; this was entirely due to preimplantation loss. It is speculated that due to a long metabolic half-life of hCG, the steroid metabolism is disturbed, causing implantation failure and/or delay of implantation. By day 21 of pregnancy, however, the fetuses of the hCG-treated rats had made up greatly for the growth retardation; they were born after a similar gestation length and with a similar birth weight as the pups of control rats.  相似文献   
2.
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.  相似文献   
3.
This review correlates the imaging findings and histological appearances seen in chordomas in a series of patients presenting at our institution, together with a published literature review. A parallel presentation of photographs of imaging findings and microscopic histological findings is made, with the aim being to enhance recognition of this uncommon but clinically significant entity.  相似文献   
4.

Background

The Abductor hallucis muscle (AbdH) plays an integral role during gait and is often affected in pathological foot conditions. The aim of this study was to evaluate the within and between-session intra-tester reliability using diagnostic ultrasound of the dorso-plantar thickness, medio-lateral width and cross-sectional area, of the AbdH in asymptomatic adults.

Methods

The AbdH muscles of thirty asymptomatic subjects were imaged and then measured using a Philips HD11 Ultrasound machine. Interclass correlation coefficients (ICC) with 95% confidence intervals (CI) were used to calculate both within and between session intra-tester reliability.

Results

The within-session reliability results demonstrated for dorso-plantar thickness an ICC of 0.97 (95% CI: 0.99–0.99); medio-lateral width an ICC: of 0.97 (95% CI: 0.92–0.97) and cross-sectional area an ICC of 0.98 (95% CI: 0.98–0.99). Between-session reliability results demonstrated for dorso-plantar thickness an ICC of 0.97 (95% CI: 0.95 to 0.98); medio-lateral width an ICC of 0.94 (95% CI 0.90 to 0.96) and for cross-sectional area an ICC of 0.79 (95% CI 0.65 to 0.88).

Conclusion

Diagnostic ultrasound has the potential to be a reliable tool for evaluating the AbdH muscle in asymptomatic subjects. Subsequent studies may be conducted to provide a better understanding of the AbdH function in foot and ankle pathologies.  相似文献   
5.
The tetrapeptide Acetyl-N-Ser-Asp-Lys-Pro (AcSDKP, Seraspenide; Ipsen- Biotech, Paris, France), an inhibitor of murine spleen colony-forming units reduces the number and the percentage in DNA synthesis of progenitors from human unfractionated bone marrow. To determine whether AcSDKP may directly affect the growth potential of purified progenitors even at the most primitive level, CD34+HLA-DRhigh and CD34++HLA-DRlow cells were highly purified by cell sorting. Then, CD34+ subsets were stimulated in liquid culture with combinations of growth factors (GFs) and AcSDKP was added for 20 hours or 6 days and cells plated in methylcellulose. After a 20-hour incubation, we show that AcSDKP (at 10(-10) mol/L) significantly inhibits the colony formation of both CD34+ subsets. Moreover, when added daily for 6 days, AcSDKP: (1) reduces the proliferation of both CD34+ cell fractions stimulated by 3 or 7 GFs, and (2) decreases the number of progenitors generated from the CD34+HLA-DRhigh and CD34++HLA-DRlow cell fractions. Furthermore, we show for the first time, using both high proliferative potential cell and long-term culture initiating cell assays, that AcSDKP inhibits the most primitive cells contained in the CD34++HLA-DRlow subpopulation. Finally, by using limiting dilution assays we demonstrated that AcSDKP acts directly at a single cell level and that its inhibitory effect is reversible and dose dependent.  相似文献   
6.
7.
We present an unusual case of haematogenous osteomyelitis in the diaphysis of the tibia of an adult leading to a subacute presentation with an extracortical abscess. Fluid from the abscess grew methicillin resistant Staphylococcus aureus (MRSA) on culture; MRSA with the same antibiogram had been grown from the patient’s blood seven years earlier following a bowel resection. Drainage of the abscess and curettage of the bone lesion together with appropriate antibiotic therapy led to resolution of the osteomyelitis.  相似文献   
8.
9.
The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states.  相似文献   
10.
The role of neutrophils in the immune response has long been regarded as mainly phagocytic, but recent publications have indicated the production of several cytokines by polymorphonuclear leucocytes (PMN). The results of the individual reports, however, vary considerably. In this study, we established a cytokine profile of pure human neutrophils and demonstrated that minor contamination of peripheral blood mononuclear cells (PBMCs) in PMN preparations can lead to false-positive results. In our hands, peripheral blood PMN fail to produce the pro-inflammatory cytokines interleukin (IL)-1beta, IL-6 and tumour necrosis factor-alpha (TNF-alpha). Instead, they secrete large amounts of the chemokine IL-8 and the anti-inflammatory IL-1 receptor antagonist (IL-1ra). Additionally, PMN preparations of a high purity show production of the chemokines macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and growth-related oncogene-alpha (GRO-alpha), as well as macrophage colony-stimulating factor (M-CSF). The neutrophil therefore represents a novelty by producing the antagonist of IL-1beta (i.e. IL-1ra) in the absence of IL-1beta itself. To support our results, we differentiated stem cells from human cord blood into PMN and monocytes, respectively. These in vitro-differentiated PMN showed the same cytokine profile as peripheral blood PMN lacking IL-1beta, while differentiated monocytes produced the expected IL-1beta in addition to IL-1ra. The clear anti-inflammatory nature of their cytokine profile enables PMN to antagonize pro-inflammatory signals in experimental conditions. It is therefore possible that PMN play a key role in immune regulation by counteracting a dysregulation of the inflammatory process. Clinical studies, in which administration of recombinant G-CSF had a favourable effect on the outcome of severe infections and even sepsis without worsening inflammation, could thus be explained by our results.  相似文献   
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