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31.
Chronic myeloid leukemia (CML) is caused by the BCR-ABL oncogene. The Philadelphia chromosome (Ph) from a reciprocal translocation, t(9;22) (q34;q11) causes a fusion gene, BCR-ABL, that encodes a constitutively active tyrosine kinase. Treatment of CML by imatinib is effective to control the tyrosyl phosphorylation of the protein related to the cell signaling. BCR-ABL mRNA is overexpressed in the minimal residual disease (MRD), known as an early sign of relapse. Between December 2005 and June 2008, we measured BCR-ABL mRNA levels in the bone marrow (BM) from patients by quantitative real-time polymerase chain reaction (RQ-PCR) in Aomori Prefectural Central Hospital. Eighty-six samples from 26 patients were collected. Among the 26 CML patients, 11 patients (42%) were in the pretreatment group. Seven (64%) of the 11 patients achieved complete molecular response (CMR). In the post-treatment group consisting of the remaining 15 patients, 9 (60%) patients achieved CMR. The patients receiving imatinib at a dose over 300 mg per day required 13 (6-77) months [median (range)] to achieve CMR. On the other hand, the patients receiving a dose below 300 mg per day required 29.5 (11-84) months [median (range)]. When BCR-ABL mRNA was detected during the treatment course of patients with CMR, careful observation of BCR-ABL mRNA was useful for tracking the clinical course of patients. In conclusion, the BCR-ABL mRNA level was useful for monitoring the clinical course in 26 patients with CML.  相似文献   
32.
Bovine adrenal glomerulosa cells are primed by an initial treatment with angiotensin II (AngII) to respond with enhanced secretion to a second exposure to AngII or agents that increase calcium influx. We hypothesized that the mechanism of priming involves a persistent increase in diacylglycerol (DAG) generated via sustained activity of phospholipase D (PLD). In this report, we sought to define the time frame of this priming response as well as determine its mechanism using assays of aldosterone secretion, PLD activation, and radiolabeled diacylglycerol levels. We found that in primary cultures priming was observed for up to 50 min after AngII washout, suggesting that the priming window is protracted in these cultures relative to freshly isolated cells. The phorbol ester, phorbol 12,13-dibutyrate (PDBu), was used to investigate the role of sustained PLD activation in the persistent DAG and priming responses. PDBu was able to both prime glomerulosa cells to respond with enhanced secretion to AngII and elicit a persistent increase in DAG after PDBu washout. This persistent increase in DAG levels with an initial exposure to PDBu or AngII was not the result of maintained PLD activity after agent removal because PLD activation returned to basal levels by 30 min after washout. Finally, inhibition of PLD signaling during the initial AngII treatment inhibited the subsequent response to AngII or another agent that increases calcium influx. Thus, our results suggest that persistent DAG resulting from PLD signaling mediates the priming response to AngII or PDBu.  相似文献   
33.
One hundred children, exposed prenatally to radiation after the Chernobyl nuclear power plant accident, and 50 nonexposed classmates were examined between the ages of 11 and 13 years old using neuropsychiatric tests, WISC, EEG, and visual evoked potentials. Individual prenatal radiation doses were reconstructed for all examined children. The exposed children were found to have more neuropsychiatric disorders, left-brain neurological signs, lower full-scale and verbal IQ, IQ discrepancies with verbal decrement, disorganized EEG patterns, an excess of lateralized-to-left frontotemporal region delta and beta power with depression of theta and alpha power, and interhemispheric inversion visual information processing. Mothers' mental health, stress, and prenatal irradiation contributed to these effects, along with several confounding factors.  相似文献   
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Thrombospondins (TSPs) are a family of five secreted multimeric matricellular proteins that share homology in the type II and III repeats and carboxy-terminal region. Type I repeats, also known as properdin or thrombospondin repeats (TSRs), are found in TSP1/2, but not TSP3-5. A variety of other secreted proteins contain TSRs, including the novel extracellular molecules, R-spondins. TSP family and many TSR-containing proteins, including R-spondins, are highly expressed in skeletal tissues during development and postnatal. TSP2 regulates the osteoblast lineage, influencing bone mass and geometry, as well as response to fracture healing, ovariectomy, and mechanical loading. Compound knockout mice of TSPs have revealed important mechanistic insights. TSP1/2 knockout mice have craniofacial dysmorphism, and TSP1/3/5 compound knockout mice display growth plate abnormalities. R-spondins promote osteoblast differentiation and R-spondin-2 deficiency results in skeletal developmental defects. Overall, TSP and other TSR molecules influence multiple aspects of bone development and remodeling.  相似文献   
36.
We report a new mutation, Asn185Asp, in exon 6 of the ferroportin gene (FPN1) in 15 members of three successive generations of a Canadian family of Scandinavian origin with autosomal dominant hemochromatosis. Hyperferritinemia with low transferrin saturation was noted in younger family members, seven of whom were aged 20 years or less at the time of diagnosis. In those individuals first diagnosed with hemochromatosis in later life, marked hyperferritinemia was accompanied by high transferrin saturation. In contrast to the phenotype of high ferritin with low saturation first reported for ferroportin disease, this family demonstrates a phenotype of iron indices that varies with age.  相似文献   
37.
This 2‐study research examined staff and parent predictors of parent engagement in after‐school programs. A parent engagement measure tailored to after‐school programs was developed based on existing theory and literature. Two distinct factors, parent engagement and parent participation, emerged from factor analyses and were subsequently tested. A 2‐level model was run on 4 program/staff and 6 parent predictors using staff and parent data from 26 after‐school program sites (Study 1) and nine sites (Study 2). Program quality, staff educational levels, and length of employment in the after‐school program were significantly associated with parent engagement and parent participation but in opposite directions, with other findings contrary to hypotheses. For parent factors of engagement and participation, there was a significant positive association between parental age and parent engagement, while having more than 2 children in a program was significantly and positively associated with parent participation only. Results and implications are discussed.  相似文献   
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39.
DNA transfer and its possible role in explaining the presence of a biological sample at a crime scene is becoming more prevalent in criminal investigations and related court proceedings. To assist understanding of DNA transfer and assess the extent to which we can utilise already available information regarding transfer of DNA we compare transfer rates determined from mock multi-step transfer scenarios with transfer rates predicted by the application of currently available transfer rate data. The transfer results obtained from the scenarios tested were, in some instances, different (both lower and higher rates) from those predicted. These discrepancies are most likely the result of the impact of as yet untested variables. These may include the variations in substrate type, transfer area size and environmental factors such as temperature and humidity among others. Whilst detailed re-enactments of proposed transfer scenarios, that take into account the many possibly relevant aspects affecting transfer are desirable, to provide an accurate likelihood estimate, these are not always possible. The application of detailed transfer rate tables that include data on the many factors affecting transfer could provide a useful substitute for evaluating the likelihood of specific transfer events. The value and accuracy derived from applying such tables will improve as more research in this area is conducted and the tables expanded and refined.  相似文献   
40.
The modulatory role of extracellular nucleotides and adenosine in relevance to purinergic cell signaling mechanisms has long been known and is an object of much research worldwide. These extracellular nucleotides are released by a variety of cell types either innately or as a response to patho‐physiological stress or injury. A variety of surface‐located ecto‐nucleotidases (of four major types; nucleoside triphosphate diphosphohydrolases or NTPDases, nucleotide pyrophosphatase/phosphodiesterases or NPPs, alkaline phosphatases APs or ALPs, and ecto‐5′‐nucleotidase or e5NT) are responsible for meticulously controlling the availability of these important signaling molecules (at their respective receptors) in extracellular environment and are therefore crucial for maintaining the integrity of normal cell functioning. Overexpression of many of these ubiquitous ecto‐enzymes has been implicated in a variety of disorders including cell adhesion, activation, proliferation, apoptosis, and degenerative neurological and immunological responses. Selective inhibition of these ecto‐enzymes is an area that is currently being explored with great interest and hopes remain high that development of selective ecto‐nucleotidase inhibitors will prove to have many beneficial therapeutic implications. The aim of this review is to emphasize and focus on recent developments made in the field of inhibitors of ecto‐nucleotidases and to highlight their structure activity relationships wherever possible. Most recent and significant advances in field of NTPDase, NPP, AP, and e5NT inhibitors is being discussed in detail in anticipation of providing prolific leads and relevant background for research groups interested in synthesis of selective ecto‐nucleotidase inhibitors.  相似文献   
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