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91.

Background

Sirtuin 1 (SIRT 1) and malondialdehyde (MDA) were implicated in metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) pathophysiology.

Aims and methods

This cross-sectional study aimed to investigate both SIRT 1 and MDA in 30 lean healthy control, 31 normoglycemic MetS subjects and 30 MetS-Pre/T2DM drug naïve. C orrelation studies were established for both biomarkers with adiposity indices [conicity index (CI), waist circumference (WC), weight-to-height (WHtR) ratio, weight-to-hip (WHR) ratio, hip circumference (HC), and body adiposity index (BAI)], hematological indices [red cell distribution width (RDW), mean platelet volume (MPV), platelet-to-lymphcyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR)] and atherogenicity indices (atherogenicity index of plasma (AIP?=?log10TG/HDL-C ratio), TC/HDL-C and LDL-C/HDL-C ratios].

Results

SIRT1 levels (ng/mL) were markedly lower in both MetS groups (2.12?±?0.06 and 2.32?±?0.19, respectively, vs. controls 4.73?±?0.15; P?<?0.05). Conversely, a gradual increase in MDA levels (μM) was attained (MetS 72?±?3.3 and MetS pre-T2DM 81?±?6.1 vs. controls 62?±?3.5; P?>?0.05). A significant inverse MDA-SIRT1 relationship was observed (P?=?0.006). SIRT1 correlated inversely with all the studied adiposity (WC: P?<?0.001, HC: P?<?0.001, WHR: P?<?0.001, C-index: P?<?0.001, BAI: P?<?0.001) and atherogenicity indices (AIP: P?<?0.001, TC/HDL-C: P?<?0.001, LDL-C/HDL-C: P?<?0.001) as well as MPV (P?<?0.01). Whereas MDA directly with WHtR, CI and BAI (WC: P?<?0.01, HC: P?<?0.05, BMI: P?<?001, WHtR: P?<?0.001, C-index: P?<?0.005, BAI: P?<?0.01).

Conclusion

The substantial variations and correlations emphasize a potential molecular role of SIRT1 and MDA in the pathophysiology of MetS and pre/T2DM.  相似文献   
92.
Cultured mouse lymphosarcoma cells are killed on exposure to 0.1 mM N(6),O(2')-dibutyryl-adenosine 3':5'-cyclic monophosphate. A population of cells resistant to the killing effect of dibutyryl cyclic AMP at concentrations as high as 1 mM was selected. The growth characteristics of the resistant cells were similar to those of the sensitive parental line. However, the resistant cells contain less cytoplasmic cyclic AMP-binding proteins and decreased cyclic AMP-stimulated protein kinase activity. It is proposed that transition from sensitivity to resistance to dibutyryl cyclic AMP in lymphoma cells is connected with a modification of the cyclic AMP-binding protein, which appears to be the regulatory subunit of the cyclic AMP-activated protein kinase.  相似文献   
93.
BACKGROUND: Serum citrulline is a marker for acute cellular rejection (ACR) after intestinal transplantation; however, its clinical utility has not yet been established. The goal of this study was to determine clearcut serum levels beyond which the diagnosis of acute rejection could be supported or refuted, and predictors of citrulline levels posttransplant from which more accurate estimates of sensitivity and specificity could be obtained. METHODS: Since March 2004, we obtained 2135 dried blood spot (DBS) citrulline samples from 57 intestinal transplant recipients at or beyond 3 months posttransplant. Stepwise linear regression was performed to determine the most significant multivariable predictors of the patient's DBS citrulline level. RESULTS: Seven characteristics were associated with a significantly lower citrulline in multivariable analysis: presence of mild, moderate, or severe ACR; presence of bacteremia or respiratory infection; pediatric age; and time from transplant to DBS sample (P<0.00001 in each case). Using a <13 vs. > or =13 micromoles/L cutoff point, the sensitivity for detecting moderate or severe ACR and the negative predictive value were high (96.4% and >99% respectively). Specificity was 54% to 74% in children and 83% to 88% in adults. CONCLUSIONS: Citrulline levels <13 micromoles/L should alert the clinical team that a serious problem (rejection or infection) could be looming in a previously stable intestinal recipient. Levels > =13 micromoles/L practically rule out moderate or severe rejection.  相似文献   
94.
This column presents an overview of Rogerian nursing science-based research. In Rogers' own words, she fostered the development of nursing science with a diversity of methods. She encouraged both qualitative and quantitative approaches and the development of new research methods and tools. Her only caveat was that theoretical conceptualization and research method must match.  相似文献   
95.
X-ray absorption spectroscopy of frozen intact tissues shows that in rats exposed to a range of treatments involving cadmium, alone or in combination with other metal ions, the coordination environment of cadmium is consistent in both the liver and kidney. Comparison of the spectra from the rat tissues to biologically relevant model compounds indicates that the vast majority of the cadmium is bound to metallothionein in these tissues.  相似文献   
96.
Ehrlichiae are small gram-negative obligately intracellular bacteria that multiply within vacuoles of their host cells and are associated for a part of their life cycle with ticks, which serve as vectors for vertebrate hosts. Two morphologically and physiologically different ehrlichial cell types, reticulate cells (RC) and dense-cored cells (DC), are observed during experimental infection of cell cultures, mice, and ticks. Dense-cored cells and reticulate cells in vertebrate cell lines alternate in a developmental cycle. We observed ultrastructure of RC and DC of Ehrlichia muris in morulae in salivary gland cells and coinfection with Borrelia burgdorferi sensu lato (sl), "Candidatus Rickettsia tarasevichiae," and a flavivirus (presumably, tick-borne encephalitis virus [TBEV]) of Ixodes persulcatusticks collected in the Cis-Ural region of Russia. Polymerase chain reaction revealed 326 (81.5%) of 400 ticks carrying at least one infectious agent, and 41.5% (166 ticks) were coinfected with two to four agents. Ehrlichiae and rickettsiae were identified by sequencing of 359 bp of the 16S rRNA gene of E. muris and of 440 bp of the 16S rRNA gene and 385 bp of the gltA gene of "R. tarasevichiae." Different organs of the same tick harbored different microorganisms: TBEV in salivary gland and borreliae in midgut; E. muris in salivary gland; and "R. tarasevichiae" in midgut epithelium. Salivary gland cells contained both RC and DC, a finding that confirmed the developmental cycle in naturally infected ticks. Dense-cored cells in tick salivary glands were denser and of more irregular shape than DC in cell cultures. Ehrlichia-infected salivary gland cells had lysed cytoplasm, suggesting pathogenicity of E. muris for the tick host at the cellular level, as well as potential transmission during feeding. Rickettsiae in the midgut epithelial cells multiplied to significant numbers without altering the host cell ultrastructure. This is the first demonstration of E. muris, "R. tarasevichiae," and the ehrlichial developmental cycle in naturally infected I. persulcatus sticks.  相似文献   
97.
98.
Malinski VM 《Nursing science quarterly》2006,19(1):7-12; discussion 6
In this column, the author provides a general overview of selected theories derived from Rogerian nursing science. After a brief discussion of the Rogerian perspective, she highlights representative theories. She suggests that ongoing development of proposed theories has been relatively slow for two main reasons. First, scholars still use the 1970 book as a major reference. Unfortunately, despite her promise to do so, Rogers never updated the 1970 book and admitted on many occasions that it would more accurately reflect her refinement of her science if a major portion of the pages were torn out. Second, theories were often proposed by doctoral candidates who changed focus in their careers postdoctorate. Despite this, there is a fascinating body of theories in various stages of development for Rogerian scholars to pursue.  相似文献   
99.
BACKGROUND: In an attempt to reduce both initial and long-term (nephrotoxic) calcineurin inhibitor maintenance dosage and totally eliminate maintenance corticosteroids, alemtuzumab (Campath-1H) was used as induction therapy in first cadaver and non-HLA-identical living donor renal transplantation. METHODS: Forty-four de novo renal allograft recipients were treated with Campath-1H (0.3 mg/kg) on days 0 and 4 postoperatively, preceded by methylprednisolone boluses. Maintenance target 12-hr tacrolimus trough levels of 5 to 7 ng/mL were operational from the outset as well as (reduced) mycophenolate mofetil dosage of 500 mg twice daily. No corticosteroids were planned to be given after the first week postoperatively. RESULTS: With a median follow-up of 9 (range, 1-19) months, patient and graft survival rates are each at 100%. Biopsy-proven acute rejection was diagnosed in four patients. Infections requiring hospitalization developed in four patients. Thirty-eight recipients remain without the need for long-term corticosteroid therapy. CONCLUSIONS: In an early assessment, the combination of Campath-1H, low dosing of tacrolimus and mycophenolate mofetil, and avoidance of maintenance corticosteroid use seems to be safe and effective for kidney transplant recipients. Long-term outcomes will be reported in the future.  相似文献   
100.
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