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101.
This article presents the use of captured data within the range of patient care activities of the dental practitioner with an emphasis on prosthodontic activities. It describes the use of computer technology in dentistry during a typical patient encounter in a dental care facility. The oral health record, the need for speech recognition technology, and existing documentation software are discussed. Ongoing development of the capabilities of Clinical Decision Support (CDS) systems is becoming an important part of the oral health setting; including systems applicable to prosthodontics. These systems all rely on a common standardized structure for the electronic (oral) health record (EHR/EOHR). Current developments in radiological technology and digital imaging are explained as well as fundamentals of decision support systems clarified. Recent developments in the representation of domain knowledge as well as the implementation of a dental nomenclature and metathesaurus are also presented. A quality matrix identifies target values for dental informatics while demonstrating an "importance-weighting" of dental characteristics.  相似文献   
102.
Thin basement membrane nephropathy   总被引:17,自引:0,他引:17  
Thin basement membrane nephropathy. Thin basement membrane nephropathy (TBMN) is the most common cause of persistent glomerular bleeding in children and adults, and occurs in at least 1% of the population. Most affected individuals have, in addition to the hematuria, minimal proteinuria, normal renal function, a uniformly thinned glomerular basement membrane (GBM) and a family history of hematuria. Their clinical course is usually benign. However, some adults with TBMN have proteinuria >500 mg/day or renal impairment. This is more likely in hospital-based series of biopsied patients than in the uninvestigated, but affected, family members. The cause of renal impairment in TBMN is usually not known, but may be due to secondary focal segmental glomerulosclerosis (FSGS) or immunoglobulin A (IgA) glomerulonephritis, to misdiagnosed IgA disease or X-linked Alport syndrome, or because of coincidental disease. About 40% families with TBMN have hematuria that segregates with the COL4A3/COL4A4 locus, and many COL4A3 and COL4A4 mutations have now been described. These genes are also affected in autosomal-recessive Alport syndrome, and at least some cases of TBMN represent the carrier state for this condition. Families with TBMN in whom hematuria does not segregate with the COL4A3/COL4A4 locus can be explained by de novo mutations, incomplete penetrance of hematuria, coincidental hematuria in family members without COL4A3 or COL4A4 mutations, and by a novel gene locus for TBMN. A renal biopsy is warranted in TBMN only if there are atypical features, or if IgA disease or X-linked Alport syndrome cannot be excluded clinically. In IgA disease, there is usually no family history of hematuria. X-linked Alport syndrome is much less common than TBMN and can often be identified in family members by its typical clinical features (including retinopathy), a lamellated GBM without the collagen alpha3(IV), alpha4(IV), and alpha5(IV) chains, and by gene linkage studies or the demonstration of a COL4A5 mutation. Technical difficulties in the demonstration and interpretation of COL4A3 and COL4A4 mutations mean that mutation detection is not used routinely in the diagnosis of TBMN.  相似文献   
103.
OBJECT: The authors have developed an intracranial near-infrared (NIR) probe that analyzes the scattering of light emitted from its tip to measure the optical properties of cerebral tissue. Despite its success in distinguishing graymatter from white matter in humans during stereotactic surgery, the limits of this instrument's resolution remain unclear. In this study, the authors determined the spatial resolution of this new probe by using a rodent model supplemented with phantom measurements and computer simulation. METHODS: A phantom consisting of Intralipid and gelatin was constructed to resemble a layer of white matter overlying a layer of gray matter. Near-infrared measurements were obtained as the probe was inserted through the gray-white matter transition. A computer simulation of NIR measurements through a gray-white matter transition was also performed using Monte Carlo techniques. The NIR probe was then used to study 19 tracks from the cortical surface through the corpus callosum in an in vivo rodent preparation. The animals were killed and histological sections through the tracks were obtained. Data from the phantom models and computer simulations showed that the NIR probe samples a volume of tissue extending 1 to 1.5 mm in front of the probe tip (this distance is termed the "lookthrough" distance). Measurements obtained from an NIR probe passing through a thin layer of white matter consisted of an initial segment of increasing values, a maximum (peak) value, and a trailing segment of decreasing values. The length of the initial segment is the lookthrough distance, the position of the peak indicates the location of the superficial white matter boundary, and the length of the trailing segment is the thickness of the layer. These considerations were confirmed in experiments with rodents. All tracks passed through the corpus callosum, which was demonstrated as a broad peak on each NIR graph. The position of the dorsal boundary of the corpus callosum and its width (based on histological measurements) correlated well with the peak of the NIR curve and its trailing segment, respectively. The initial segments correlated well with estimates of the lookthrough distance. Five of the tracks transected the smaller anterior commissure (diameter 0.2 mm), producing a narrow NIR peak at the correct depth. CONCLUSIONS: Data in this study confirm that the NIR probe can reliably detect and measure the thickness of layers of white matter as thin as 0.2 mm. Such resolution should be adequate to detect larger structures of interest encountered during stereotactic surgery in humans.  相似文献   
104.
Purpose. Sterically stabilized phospholipid micelles (SSMs) composed of poly(ethylene glycol-2000)-grafted distearoyl phosphatidylethanolamine (PEG(2000)-DSPE) are new and promising lipid-based carriers for water-insoluble drugs. This study investigates and compares sterically stabilized mixed micelles (SSMM), composed of (PEG(2000)-DSPE) plus egg-phosphatidylcholine, with SSM as a novel delivery system for improved solubilization of water-insoluble drugs using paclitaxel as a model. Methods. Paclitaxel was solubilized in SSM (P-SSM) and SSMM (P-SSMM) by coprecipitation and rehydration with isotonic 0.01M HEPES buffer, pH 7.4. After separation of excess drug by centrifugation, mean particle size and morphology of particles in the supernatant were determined by quasi-elastic light scattering and transmission electron microscopy. The solubilization potentials of SSMM and SSM for paclitaxel were determined by reverse phase high pressure liquid chromatography (RP-HPLC). Cytotoxic activity of paclitaxel in SSMM, SSM, and dimethyl sulfoxide (10% DMSO) was determined against human breast cancer cells (MCF-7). Results. Mean hydrodynamic diameter of P-SSMM and P-SSM were 13.1 ± 1.1 nm and 15 ± 1 nm (n = 3), respectively. SSMM solubilized 1.5 times more paclitaxel than SSM for the same total lipid concentration. Solubilized paclitaxel amount increased linearly with an increase in lipid concentration. A therapeutically relevant lipid concentration (15 mM) of SSMM solubilized 1321 ± 48g/ml of paclitaxel. Paclitaxel in the absence of sufficient SSM aggregated to form lipid-coated crystals. P-SSMM, P-SSM, and paclitaxel in DMSO had comparable cytotoxic activities against MCF-7 cells. Conclusions. SSMM showed increased solubilization potential compared with SSM while retaining all of its own advantages. Therefore, it can be used as an improved lipid-based carrier for water-insoluble drugs.  相似文献   
105.
Colorectal carcinoma in black and white race   总被引:5,自引:0,他引:5  
Worldwide, colorectal carcinoma (CRC) varies by race-ethnicity. The highest incidence occurs in whites of European descent. Rates in blacks of South Africa are much lower, but rise with migration to westernized countries, i.e. African Americans (blacks) in the US. In the US, CRC age-specific incidence rates increased dramatically with biologic aging for black and white men and women. For all ages, rates were slightly higher for black than for whites. Among whites, overall annual rates peaked in the 1980s then declined. Stage- and subsite-specific rate shifts suggested earlier detection of cancers through screening, particularly in the distal colon. Blacks have not experienced the same stage- and subsite temporal shifts, which were observed in whites. CRC racial differences have been attributed to biologic and/or non-biologic factors as well as to routine screening patterns. Racial variations demonstrate the need for a more comprehensive understanding of colorectal carcinogenesis, epidemiology, and colorectal screening patterns for low- and high-risk populations.  相似文献   
106.
The determination of brain tumor margins both during the presurgical planning phase and during surgical resection has long been a challenging task in the therapy of brain tumor patients. Using a model of gliosarcoma with stably green fluorescence protein-expressing 9L glioma cells, we explored a multimodal (near-infrared fluorescent and magnetic) nanoparticle as a preoperative magnetic resonance imaging contrast agent and intraoperative optical probe. Key features of nanoparticle metabolism, namely intracellular sequestration by microglia and the combined optical and magnetic properties of the probe, allowed delineation of brain tumors both by preoperative magnetic resonance imaging and by intraoperative optical imaging. This prototypical multimodal nanoparticle has unique properties that may allow radiologists and neurosurgeons to see the same probe in the same cells and may offer a new approach for obtaining tumor margins.  相似文献   
107.
Epididymis and vas deferens form part of the male internal genital tract and are dependent on androgens for their growth and development. To better understand the molecular action of androgens during male genital tract development, protein expression profiles were generated using two-dimensional gels, for rat epididymides and vasa deferentia isolated on embryonic days (E) 17-21. Proteins that were differentially expressed between E17 and E21 were cut from the gels, digested into tryptic peptides and analyzed on a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer. Using this approach, 20 proteins could be identified that were regulated in time and were categorized into cytoskeletal proteins, nuclear proteins, transport proteins, chaperones, and enzymes (mainly glycolytic). Furthermore, epididymides and vasa deferentia isolated on E19 were cultured in vitro in the absence or presence of 10 nm of the synthetic androgen R1881, for 9, 24, and 48 h. Under these conditions, regulation and posttranslational modification were observed for glyceraldehyde 3-phosphate dehydrogenase, triosephosphate isomerase, heterogeneous nuclear ribonucleoprotein A2/B1 and heterogeneous nuclear ribonucleoprotein A3, similar to the observed changes in vivo. In addition, posttranslational modification of RhoGDI1 (also named RhoGDIalpha) was found in response to androgen. Androgen-induced posttranslational modification of RhoGDI1 and glycolytic enzymes may be an important functional link between signaling pathways and cytoskeletal rearrangements in control of growth and development of the male internal genital tract.  相似文献   
108.
S 100 B is a glial marker of cerebral Injury. In a previous clinical study, we found an S 100 B increase within the first 24 h in patients with multiple trauma and hemorrhagic shock but without cerebral trauma. The aim of our current experimental study was to determine whether this posttraumatic S 100 B increase is caused by extracerebral soft tissue injury or by hemorrhagic shock and whether it is associated with the severity of hemorrhagic shock. Hemorrhagic shock was achieved by bleeding anesthetized rats to a mean arterial pressure (MAP) of 30-35 mmHg through a femoral catheter and maintaining this MAP until incipient decompensation. At incipient decompensation, MAP was either increased immediately to 40-45 mmHg (moderate shock) or was maintained until 40% of shed blood had been returned (severe shock), and then increased to 40-45 mmHg. Resuscitation was provided after 40-45 mmHg MAP had been maintained for 40 min. Soft tissue injury was achieved by midline laparotomy performed at the onset of hemorrhagic shock or without shock and was maintained for 30 min. Hemorrhagic shock caused an early S 100 B increase at the onset of decompensation. S 100 B remained increased for 24 h and was significantly higher after severe than after moderate shock. In contrast, soft tissue injury without hemorrhagic shock caused no S 100 B increase. The data presented demonstrate for the first time that the S 100 B increase is induced by hemorrhagic shock and is associated with the severity of shock.  相似文献   
109.
Purpose. To determine whether human vasoactive intestinal peptide (VlP)-poly(ethylene glycol) (PEG)-grafted distearoyl-phosphatidyleth-anolamine (DSPE) micelles elicit potent and stable vasodilation in vivo. Methods. PEG-DSPE micelles were prepared by co-precipitation. VIP was loaded into micelles by incubation at room temperature. Vasoactivity of VIP in SSM was determined by monitoring changes in diameter of resistance arterioles in the in situ hamster cheek pouch using intravital microscopy. Results. VIP easily undergoes self-assembly into small PEG-DSPE micelles (mean [±SEM] size, 18 ± 1 nm) in a time-dependent fashion. This generates a potent vasoactive matrix at nanomole concentrations of VIP as manifested by ~3-fold potentiation and prolongation of vasodilation relative to that evoked by aqueous VIP alone (p < 0.05). This response is specific and mediated by the L-arginine/nitric oxide (NO) biosynthetic pathway. Micellar VIP dispersion remains vasoactive for at least 14 days after preparation and storage at 4°C. Conclusions. A novel, self-associated, small and stable PEG-DSPE micellar formulation of VIP amplifies vasodilation in the in situ peripheral microcirculation in a specific fashion by elaborating NO. An optimized formulation could be considered for certain cardiovascular disorders associated with L-arginine/NO biosynthetic pathway dysfunction.  相似文献   
110.
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