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111.
Ornithine decarboxylase (ODC; EC 4.1.1.17) and its antizyme (Az), a protein non-competitive inhibitor of ODC, form a complex in germinated barley ( Hordeum vulgare L. cv. Georgia) seeds. The ODC-Az complex is very stable, but dissociates by treatment with 10% ammonium sulfate. ODC-Az complex is present in the cytosol, and it can also be extracted from germinated barley seed chromatin with 2 M NaCl.  相似文献   
112.
A mathematical approach of blood flow within an abdominal aortic aneurysm (AAA) with intraluminal thrombus (ILT) is presented. The macroscale formation of ILT is modeled as a growing porous medium with variable porosity and permeability according to values proposed in the literature. The model outlines the effect of a porous ILT on blood flow in AAAs. The numerical solution is obtained by employing a structured computational mesh of an idealized fusiform AAA geometry and applying the Galerkin weighted residual method in generalized curvilinear coordinates. Results on velocity and pressure fields of independent cases with and without ILT are presented and discussed. The vortices that develop within the aneurysmal cavity are studied and visualized as ILT becomes more condensed. From a mechanistic point of view, the reduction of bulge pressure, as ILT is thickening, supports the observation that ILT could protect the AAA from a possible rupture. The model also predicts a relocation of the maximum pressure region toward the zone proximal to the neck of the aneurysm. However, other mechanisms, such as the gradual wall weakening that usually accompany AAA and ILT formation, which are not included in this study, may offset this effect.  相似文献   
113.
Pioneering studies within the last few years have allowed the in vitro expansion of tissue‐specific adult stem cells from a variety of endoderm‐derived organs, including the stomach, small intestine, and colon. Expansion of these cells requires activation of the receptor Lgr5 by its ligand R‐spondin 1 and is likely facilitated by the fact that in healthy adults the stem cells in these organs are highly proliferative. In many other adult organs, such as the liver, proliferating cells are normally not abundant in adulthood. However, upon injury, the liver has a strong regenerative potential that is accompanied by the emergence of Lgr5‐positive stem cells; these cells can be isolated and expanded in vitro as organoids. In an effort to isolate stem cells from non‐regenerating mouse livers, we discovered that healthy gallbladders are a rich source of stem/progenitor cells that can be propagated in culture as organoids for more than a year. Growth of these organoids was stimulated by R‐spondin 1 and noggin, whereas in the absence of these growth factors, the organoids differentiated partially toward the hepatocyte fate. When transplanted under the liver capsule, gallbladder‐derived organoids maintained their architecture for 2 weeks. Furthermore, single cells prepared from dissociated organoids and injected into the mesenteric vein populated the liver parenchyma of carbon tetrachloride‐treated mice. Human gallbladders were also a source of organoid‐forming stem cells. Thus, under specific growth conditions, stem cells can be isolated from healthy gallbladders, expanded almost indefinitely in vitro, and induced to differentiate toward the hepatocyte lineage.  相似文献   
114.
Copper(II) complexes of diclofenac with interesting anti-inflammatory profiles have been prepared and studied by infrared and electronic spectroscopy. In the solid state and in polar and coordinating solvents, all the complexes are solvated binuclear carboxylato-bridged complexes, [Cu(L)2(S)]2, where L is monodeprotonated diclofenac and S is the axially bonded solvent. The effect of the copper(II) complexes on the in vitro DNA strand breakeage was studied by agarose gel electrophoresis. Relaxation or double stranded scissions of pDNA were observed leading to the formation of linear pDNA. Treatment of pDNA with high concentrations of these compounds caused a disappearance of pDNA. For the parent drug, sodium diclofenac, no effect on the pDNA was observed. This study presents some indications that the binuclear copper(II) complexes, [Cu(L)2(S)]2, could have some relevance in the treatment of tumor cell lines.  相似文献   
115.
Chlorobium tepidum is a Gram-negative bacterium of the green sulfur phylum (Chlorobia). Chlorobia are obligate anaerobic photolithoautotrophs that are widely distributed in aquatic environments where anoxic layers containing reduced sulfur compounds are exposed to light. The envelope of C. tepidum is a complex organelle composed of the outer membrane, the periplasm–peptidoglycan layer, and the cytoplasmic membrane. In addition to the outer and plasma membranes, C. tepidum contains chlorosomes attached to the cytoplasmic side of the plasma membrane. Each cellular compartment has a unique set of proteins, called sub-proteome. An important aim of proteome analysis is to study the level of the expressed genes and their response to environmental changes. Membrane protein studies are of primary importance to understand how nutrients are transported inside the cell, how toxic molecules are exported, and the mechanisms of photosynthesis and energy metabolism.  相似文献   
116.

Background  

The red flour beetle Tribolium castaneum has developed into an insect model system second only to Drosophila. Moreover, as a coleopteran it represents the most species-rich metazoan taxon which also includes many pest species. The genetic toolbox for Tribolium research has expanded in the past years but spatio-temporally controlled misexpression of genes has not been possible so far.  相似文献   
117.
Elucidation of the molecular events that underlie respiratory epithelium carcinogenesis still remains a largely unresolved issue. Various new therapeutic interventions are in advanced clinical testing or in daily clinical practice based on available preclinical findings. However, the complex molecular interplay that characterizes carcinogenesis requires further investigation to identify the pivotal factors and their interactions that might render the treatment of these malignancies more effective. Insulin-like growth factor-1 (IGF-1) network is a new important signalling cascade in lung carcinogenesis. Here, we integrate updated results that further support the significance of IGF-1 molecular circuitry in respiratory epithelium tumourigenesis, and pose future perspectives regarding its optimal use in the therapeutic field.  相似文献   
118.
HLA-mismatched natural killer (NK) cells have shown efficacy in acute myeloid leukemia, and their adoptive transfer in patients with other malignancies has been proven safe. This phase I clinical trial was designed to evaluate safety (primary endpoint) and possible clinical efficacy (secondary endpoint) of repetitive administrations of allogeneic, in vitro activated and expanded NK cells along with chemotherapy in patients with advanced non-small cell lung cancer (NSCLC). Patients with unresectable, locally advanced/metastatic NSCLC receiving 1st/2nd line chemotherapy were eligible to receive 2–4 doses of activated NK cells from two relative donors. Donor’s CD56+ cells were cultured for 20–23 days with interleukin-15 (IL-15) and hydrocortisone (HC) and administered intravenously between chemotherapy cycles. Premedication with corticosteroids and/or H1 inhibitors was allowed. Sixteen patients (performance status 0–1) with adenocarcinoma (n = 13) or squamous cell carcinoma (n = 3) at stage IIIb (n = 5) or IV (n = 11) receiving 1st (n = 13) or 2nd (n = 3) line treatment were enrolled. Fifteen patients received 2–4 doses of allogeneic activated NK cells (0.2–29 × 106/kg/dose, median 4.15 × 106/kg/dose). No side effects (local or systemic) were observed. At a median 22-month follow-up (range, 16.5–26 months) 2 patients with partial response and 6 patients with disease stabilization were recorded. Median progression free survival and overall survival were 5.5 and 15 months, respectively. A 56% 1-year survival and a 19% 2-year survival were recorded. In conclusion, repetitive infusions of allogeneic, in vitro activated and expanded with IL-15/HC NK cells, in combination with chemotherapy are safe and potentially clinically effective.  相似文献   
119.
The RUBICODE project draws on expertise from a range of disciplines to develop and integrate frameworks for assessing the impacts of environmental change on ecosystem service provision, and for rationalising biodiversity conservation in that light. With such diverse expertise and concepts involved, interested parties will not be familiar with all the key terminology. This paper defines the terms as used within the project and, where useful, discusses some reasoning behind the definitions. Terms are grouped by concept rather than being listed alphabetically.  相似文献   
120.

Objective:

Increased body mass index (BMI) has been paradoxically inversely associated with the presence of angiographic coronary artery disease (CAD). Central obesity measures, considered to be more appropriate for assessing obesity‐related cardiovascular risk, have been little studied in relation to the presence of CAD. The aim was to investigate the association of central obesity with the presence of angiographic CAD as well as the prognostic significance of obesity measures in CAD prediction when added to other cardiovascular risk factors.

Design and Methods:

Patients with suspected stable CAD (n = 403, age 61 ± 10 years, 302 males) referred for diagnostic coronary angiography with documented anthropometric data were enrolled.

Results:

Significant angiographic CAD was found in 51% of patients. Both BMI (OR = 0.64 per 1 SD increase, P = 0.001) and waist circumference (WC) (OR = 0.54 per 1 SD increase, P < 0.001) were inversely associated with the presence of CAD even after adjustment for cardiovascular risk factors. In subgroup analysis, BMI and WC were significantly inversely associated with the presence of CAD in males, non diabetics, patients >60 years old and patients with Framingham risk score (FRS) >20% (P < 0.01 for all). The addition of BMI or WC in FRS‐based regression models improved prediction of CAD (P = 0.03 and P < 0.001 for BMI and WC respectively) without a significant difference between the two models (P = 0.08).

Conclusions:

Central and overall obesity were independently associated with a reduced prevalence of angiographic CAD, lending further credence to the existence of the ‘obesity paradox’. Obesity measures may further improve risk discrimination for the presence of CAD when added in an established risk score such as FRS.  相似文献   
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