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61.
The finding that an individual's genome differs as much as by many million variants from that of the human reference assembly diminished the great enthusiasm that every disease could be predicted based on nucleotide polymorphisms. Even individual cells of an organ may be specifically equipped to perform specific tasks and that the information of individual cells in a cell system is key information to understand function or dysfunction. Therefore, cytomics received great attention during the last years as it allows to quantitatively and qualitatively analyzing great number of individual cells, cell constituents, and of their intracellular and functional interactions in a cellular system and also giving the concept of analysis of these data.Exhaustive data extraction from multiparametric assays and multiple tests are the prerequisite for prediction of drug toxicity. Cytomics, as novel approach for unsupervised data analysis give a chance to find the most predictive parameters, which describe best the toxicity of a chemical. Cytomics is intrinsically connected to drug development and drug discovery.Focused on small structures, nanobioengineering is the ideal partner of cytomics, the systems biological discipline for cell population analysis. Realizing the idea "from the molecule to the patient" develops and offers chemical compounds, proteins, and other biomolecules, cells as well as tissues as instruments and products for a wide variety of biotechnological and biomedical applications.The integrative nanobioengineering combining different disciplines of nanotechnology will promote the development of innovative therapies and diagnostic methods. It can improve the precision of the measurements with focus on single cell analysis. By nanobioengineering and whole body imaging techniques, cytomics covers the field from molecules through bacterial cells, eukaryotic tissues, and organs to small animal live analysis. Toxicological testing and medical drug development are currently strongly broadening. It harbors the promise to substantially impact on various fields of biomedicine, drug discovery, and predictive medicine.As the number of scientific data is rising exponentially, new data analysis tools and strategies like cytomics and nanobioengineering take a lead and get closer to application. Bionanoengineering may strongly support the quantitative data supply, thus strengthening the rational for cytomics approach.  相似文献   
62.
We examined the synaptic targets of large non-gamma-aminobutyric acid (GABA)-ergic profiles that contain round vesicles and dark mitochondria (RLD profiles) in the perigeniculate nucleus (PGN) and the dorsal lateral geniculate nucleus (dLGN). RLD profiles can provisionally be identified as the collaterals of thalamocortical axons, because their ultrastrucure is distinct from all other previously described dLGN inputs. We also found that RLD profiles are larger than cholinergic terminals and contain the type 2 vesicular glutamate transporter. RLD profiles are distributed throughout the PGN and are concentrated within the interlaminar zones (IZs) of the dLGN, regions distinguished by dense binding of Wisteria floribunda agglutinin (WFA). To determine the synaptic targets of thalamocortical axon collaterals, we examined RLD profiles in the PGN and dLGN in tissue stained for GABA. For the PGN, we found that all RLD profiles make synaptic contacts with GABAergic PGN somata, dendrites, and spines. In the dLGN, RLD profiles primarily synapse with GABAergic dendrites that contain vesicles (F2 profiles) and non-GABAergic dendrites in glomerular arrangements that include triads. Occasional synapses on GABAergic somata and proximal dendrites were also observed in the dLGN. These results suggest that correlated dLGN activity may be enhanced via direct synaptic contacts between thalamocortical cells, whereas noncorrelated activity (such as that occurring during binocular rivalry) could be suppressed via thalamocortical collateral input to PGN cells and dLGN interneurons.  相似文献   
63.
PURPOSE: To assess the variability among clinicians in the delineation of mediastinal and hilar lymph node stations (LNS) according to the published recommendations in the treatment planning of elective nodal irradiation for lung cancer. METHODS: Nine observers delineated on axial CT scans of five cases the LNS according to the guidelines of the published Atlas. Next, the Volumes of Consensus (VC)--fitting strictly the guidelines--for each LNS and case were collectively defined. Volume of Intersection (VI) as the overlap of the Delineated Volume (DV) for each LNS, case and observer with respective VC was computed. The Concordance Index (CI) for respective LNS and observers was defined as "VI/VC x 100%". The Discordance Index (DI) for respective LNS and observers was defined as "(1-VI/VD) x 100%". RESULTS: Mean values of CI and DI for all observers were 69% and 36%, respectively. For five radiation oncologists who used to work as a team the ways of delineation were similar. The poorest reproducibility was shown for LNS 5, 7, 10R, and 10L. CONCLUSIONS: Although detailed guidelines are used there is still substantial room for improvement. More training in the use of the Atlas is recommended.  相似文献   
64.
Combination chemotherapy with gemcitabine and carboplatin administered on a 3-week cycle is used commonly in the treatment of cancer. The purpose of our study was to establish a safe dose of combined gemcitabine and carboplatin when administered on a biweekly schedule to patients with advanced solid tumors. Gemcitabine was given intravenously over 30 minutes followed by carboplatin also given intravenously over 30 minutes once every 2 weeks (one cycle). Five dose levels were examined, ranging from gemcitabine at 1250 mg/m2 to 2000 mg/m2 and carboplatin at an area under the curve of 2.5 to 3.0. Twenty-six patients were studied (18 male and 8 female) with a median age of 57 years (range, 41-83 years); ECOG performance status was 0 or 1 in 22 patients (85%); median number of prior chemotherapy regimens was 2 (range, 0-4); median number of cycles administered per patient was 3 (range, 1-9) with a total of 89 cycles. Two dose-limiting toxicities were observed. Delay in treatment was seen in a total of 8 cycles with 6 of the delays due to myelosuppression. Grade 3 or 4 hematologic toxicity rates were as follows: anemia in one cycle (1%), neutropenia in 13 cycles (15%), and thrombocytopenia in one cycle of chemotherapy (1%). There were no hospitalizations for neutropenic fever. Mild fatigue was the most common nonhematologic toxicity. The median time to progression was 40 days (mean, 49 days; range, 4-133 days). Of the 21 evaluable patients, partial response or stable disease was observed in 11 (42%). The maximum tested dose of gemcitabine at 2000 mg/m2 and carboplatin at area under the curve of 3.0 was well tolerated on a biweekly schedule. Our findings indicate that further investigation of this biweekly regimen is warranted in patients with advanced cancer.  相似文献   
65.
Assemblages of clay minerals are routinely used as proxies for paleoclimatic change and paleoenvironmental conditions in Phanerozoic rocks. However, this tool is rarely applied in older sedimentary units. In this paper, the clay mineralogy of the Doushantuo Formation in South China is documented, providing constraints on depositional conditions of the Ediacaran Yangtze platform that host the earliest animal fossils in the geological record. In multiple sections from the Yangtze Gorges area, trioctahedral smectite (saponite) and its diagenetic products (mixed-layer chlorite/smectite, corrensite, and chlorite) are the dominant clays through the lower 80 m of the formation and constitute up to 30 wt% of the bulk rock. Saponite is interpreted as an in situ early diagenetic phase that formed in alkaline conditions (pH ≥ 9). The absence of saponite in stratigraphically equivalent basin sections, 200–400 km to the south, indicates that alkaline conditions were localized in a nonmarine basin near the Yangtze Gorges region. This interpretation is consistent with crustal abundances of redox-sensitive trace elements in saponitic mudstones deposited under anoxic conditions, as well as a 10‰ difference in the carbon isotope record between Yangtze Gorges and basin sections. Our findings suggest that nonmarine environments may have been hospitable for the fauna preserved in the Yangtze Gorges, which includes the oldest examples of animal embryo fossils and acanthomorphic acritarchs.  相似文献   
66.
We report on an 8-month-old girl with a novel unbalanced chromosomal rearrangement, consisting of a terminal deletion of 4p and a paternal duplication of terminal 11p. Each of these is associated with the well-known clinical phenotypes of Wolf-Hirschhorn syndrome (WHS) and Beckwith-Wiedemann syndrome (BWS), respectively. She presented for clinical evaluation of dysmorphic facial features, developmental delay, atrial septal defect (ASD), and left hydronephrosis. High-resolution cytogenetic analysis revealed a normal female karyotype, but subtelomeric fluorescence in situ hybridization (FISH) analysis revealed a der(4)t(4;11)(pter;pter). Both FISH and microarray CGH studies clearly demonstrated that the WHS critical regions 1 and 2 were deleted, and that the BWS imprinted domains (ID) 1 and 2 were duplicated on the der(4). Parental chromosome analysis revealed that the father carried a cryptic balanced t(4;11)(pter;pter). As expected, our patient manifests findings of both WHS (a growth retardation syndrome) and BWS (an overgrowth syndrome). We compare her unique phenotypic features with those that have been reported for both syndromes.  相似文献   
67.
68.
Heart rate turbulence (HRT) analysis is a novel, non-invasive method enabling to estimate sudden cardiac death risk. Up till now it was used to determine cardiac death risk in patients suffering from congestive heart failure and especially after myocardial infarction. The aim of the study was to estimate heart rate turbulence parameters in patients with essential hypertension and to find correlations between those parameters and age, left ventricular mass and hypertension stages. Studies were performed in a group of 55 persons: 26 women (54.79 +/- 8.26 years old) and in 29 men (52.34 +/- 5.72 years old) with essential pharmacologically untreated hypertension. Patients were divided into two groups: increased (group I, n = 32) and normal left ventricle mass (group II, n = 23). In each patient 24-hour ECG Holter recording was performed and then turbulence onset (TO) (expressed in %) and turbulence slope (TS) (in ms/RR interval) were estimated. In the group of patients with increased left ventricle mass parameter TO was significantly higher (-0.74 +/- 0.24 vs -1.32 +/- 0.28; p < 0.05) and parameter TS significantly lower (5.26 +/- 1.17 vs 8.46 +/- 2.91; p < 0.01) in comparison to study subjects with normal left ventricle mass. Heart rate turbulence is decreased in people with essential hypertension and increased left ventricle mass in comparison to normal left ventricle mass group. Decreased heart rate turbulence in patients with essential hypertension and increased left ventricle mass may be a predictor of worse prognosis in that group.  相似文献   
69.
BACKGROUND: The choice of optimal therapy in a patient with borderline coronary lesion is difficult. The long-term outcome of conservatively treated patients has not yet been well defined. AIM: To analyse long-term outcome in patients with a borderline lesion in a single coronary artery who were selected for conservative treatment. METHODS: The study group consisted of 65 patients (mean age 59.4+/-7.4 years, 48 males) with (1) stable angina (CCS class I/II), (2) isolated single borderline coronary lesion (40-70% stenosis demonstrated by quantitative coronary angiography) and (3) no demonstrable ischaemia during non-invasive tests. Patients with heart failure, left ventricular ejection fraction <50% or acute coronary syndrome within 6 months preceding the study were not included. All patients were prescribed statins, angiotensin converting enzyme inhibitors and aspirin. Follow-up end-points included cardiac death, new myocardial infarction (MI) with or without ST segment elevation and revascularisation of the target coronary artery. RESULTS: The follow-up duration was 18.4+/-8.5 months (range 12-33, median 18 months). Forty nine (75%) patients remained free from angina during daily activity. Coronary events occurred in 16 (25%) patients, including three (5%) serious complications -- sudden death, new MI with ST elevation and new MI without ST elevation. The remaining 13 (20%) patients underwent percutaneous revascularisation of the target coronary artery. Coronary angiography was repeated in 16 (25%) patients. When the patients were divided into two groups according to the follow-up results (with or without coronary event), no differences in the clinical characteristics, lesion localisation and length or degree of stenosis were noted. CONCLUSIONS: (1) Conservatively treated patients with stable angina and borderline coronary stenosis have a high rate of coronary events, especially revascularisation, during a long-term follow-up. (2) Clinical parameters and quantitative coronary angiography do not identify those patients with borderline coronary lesions who are at increased risk of future coronary events.  相似文献   
70.
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