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51.
Subjects were 20 patients with tongue cancer treated between April 1996 and December 2002 with intraarterial infusion of cisplatin (60-120 mg/m2) (and docetaxel 10-30 mg/m2) and intravenous infusion of sodium thiosulfate followed by 5-fluorouracil (5-FU) (800-1000 mg/m2) for 3 to 5 days. All patients underwent radiation (50-80 Gy). Ten had stage II, 4 stage III, and 6 stage IV A disease. Complete response at the primary site was achieved in 50% for T2, 67% for T3, and 0% for T4 lesions in those undergoing IA cisplatin followed by systemic 5-FU with concurrent radiation. Complete response at the primary site was achieved in all patients given IA cisplatin and docetaxel followed by systemic 5-FU with concurrent radiation. Disease-specific survival was 75% and overall survival 69% at 5 years. Side effects of treatment were tolerable, except for grade three radiomucositis in 70% of patients and grade three bone marrow depression in one treated with weekly IA chemotherapy.  相似文献   
52.
The purpose of this study was to evaluate the durability of tubules occluded with FTLA treatment by toothbrush abrasion test on the applied surface and by measuring fluoride release from the FTLA components. Dentin specimens with simulated hypersensitive surfaces were treated with APF containing tannic acid. After which, the specimens received lanthanum-chloride-with-powdered-fluoroapatite-glass-ceramics treatment. The specimens were subjected to toothbrush abrasion test up to 6,000 strokes. SEM observation revealed that dentinal tubules of the FTLA treated specimens were completely occluded with fine deposits even after toothbrush abrasion of 6,000 strokes. EPMA analysis revealed that fluoride, lanthanum, and aluminum were the main FTLA components on the dentin surface after 6,000-stroke abrasion. To measure fluoride release from the FTLA components, a slurry was enclosed in a cellulose tube and suspended in deionized water at 37 degrees C. After fluoride was dialyzed against deionized water, a high concentration of fluoride was found to be released from FTLA the components, indicating FTLA treatment's prominent durability. These results suggested that FTLA treatment has a superior resistance against toothbrush abrasion and a high fluoride-releasing performance. These characteristics lend much weight to showing that the FTLA method is an effective and durable medicament for dentin hypersensitivity.  相似文献   
53.
We report a rare case of pleomorphic adenoma arising from the nasal septum. A 32-year-old woman presented with a 3-week-history of left-sided nasal obstruction. Computed tomographic scans revealed an oval mass, measuring about 30 mm in its greatest dimension, in the left anterior nasal cavity. The tumor arose from the anterior part of the nasal septum, and was removed endoscopically with endonasal approach. The microscopic finding showed a lobular and duct-like structures consisting of a loose chondromyxoid stroma. This lesion had histological characteristics of a pleomorphic adenoma, and this was confirmed by immunohistochemical expression of cytokeratin and S-100 protein. Her post-operative course was uneventful, and she is currently free from the disease 8 months after surgery. Diagnosis, clinical behavior and treatment of pleomorphic adenoma of the nasal septum are reviewed from perusal of the literature.  相似文献   
54.
Since the roles of thromboxane A2 (TXA2), prostacyclin (PGI2) and 8-isoprostane F2alpha in mediating vascular O2*- formation and its relation to adult respiratory distress syndrome (ARDS) is unknown, the effects of these eicosanoids on the expression of gp91phox (catalytic subunit of NADPH oxidase) and O2*- release from cultured pig pulmonary artery (PA) segments, PA vascular smooth muscle cells (PAVSMCs) and PA endothelial cells (PAECs) were investigated. PA segments, PAVSMCs and PAECs were incubated with the TXA2 analogue, U46619, (+/-LPS, tumour necrosing factor-alpha (TNF-alpha) or IL-1alpha), 8-isoprostane F2alpha and+/-iloprost (a stable PGI2 analogue) for 16 h. The formation of superoxide dismutase-inhibitable O2*- was then measured spectrophotometrically and gp91phox expression assessed using Western blotting. In parallel experiments, whole PA segments were treated with LPS, TNF-alpha and IL-alpha after which time TXA2, PGI2, PGF2alpha and 8-isoprostane F2alpha formation was measured using enzyme-linked immunoassays. U46619, PGF2alpha and 8-isoprostane F2alpha promoted the formation of O2*- in PA segments, PAVSMCs and PAECs, an effect inhibited by diphenyleneiodonium and apocynin (both NADPH oxidase inhibitors) and upregulated the expression of gp91phox in PAECs and PAVSMCs. These effects were augmented by LPS, TNF-alpha and IL-1alpha but inhibited by iloprost. Under identical incubation conditions, IL-1alpha, LPS and TNF-alpha all induced an increase in the formation of TXA2, PGF2alpha and 8-isoprostane F2alpha but reduced the concomitant formation of PGI2. These data demonstrate that LPS and cytokines influence the relative balance of TXA2, PGI2, PGF2alpha and 8-isoprostane F2alpha in pig PA, which in turn alter NADPH oxidase expression and O2*- formation. These novel findings have implications in devising effective strategies for treating ARDS.British Journal of Pharmacology (2004) 141, 488-496. doi:10.1038/sj.bjp.0705626  相似文献   
55.
56.
Qin L  Sakai M  Chimoto S  Sato Y 《Brain research》2004,1014(1-2):1-13
Although psychophysical studies have revealed involvement of spectral edges in auditory perception, little is known about neural processing. This study investigates how spectral edges are processed in neurons of alert cat primary-auditory-cortex (A1) with sustained response property. Stimuli are low-pass, high-pass and band-pass tones with sharp spectral edges whose edge-frequencies were systematically shifted, constructing edge-frequency response functions. Pure- and two-tone stimuli served to delineate excitatory and inhibitory subfields of the frequency response field (FRF). Based on the response function characteristics, cells were divided into edge-sensitive and edge-insensitive cells: the edge sensitive cells had narrow tuning to the high-edge (type-II cells) or low-edge (type-III cells) frequencies, while the edge insensitive cells were driven by any static stimuli with energy on FRF (type-I) or only very narrowband stimuli with energy confined to FRF (type-IV cells). Edge-sensitive cells showed a close correlation between the best frequencies of the single-frequency (BFSF) and edge-frequency (BFEF) response functions and between their half-height bandwidths, suggesting that the edge-frequency identification is processed along the tonotopic axis in A1. BFSF shifted (mean 0.11 octaves) into the stimulus band from the BFEF (closely corresponding to pitch shift into stimulus band from the edge frequency in human psychophysical data of edge-pitch), suggesting central mechanism of edge-pitch sensation. Type-I cells had non-significant inhibitory subfields of FRF; type-II cells had the significant inhibitory subfield on the higher frequency side; type-III cells, on the lower frequency side; and type-IV cells, on both sides, suggesting that the inhibitory mechanism characterizes the cell-type specific spectral-edge sensitivity.  相似文献   
57.
Qin L  Chimoto S  Sakai M  Sato Y 《Brain research》2004,1024(1-2):167-175
The study of the influence of spectral envelopes of complex tones on cortical neuron discharges is important with respect to understanding the formant processing of vowels. That the sharpness of formants can contribute to the vowel quality has previously been shown in psychophysical experiments. However, it is unknown how this parameter is reflected by cortical neuron discharges, especially when a formant falls into different portions of the neuronal frequency receptive field (FRF). To show this is the aim of this study focusing on the sustained discharging neurons in the low frequency portion of cat primary auditory cortex (A1). The stimuli were multi-frequency tones whose spectral envelope was sinusoidally modulated with a peak fixed at a neuron's best frequency. The modulation depth, defined as damping-amplitude (DA), varied systematically. Stimulus bandwidth also varied systematically. Large DA at off-center frequencies produces a prominent spectral peak with steep slope, whereas small DA has a less well-defined spectral peak with gentle slope. Single frequency and two tone stimuli served to delineate the excitatory and inhibitory subfields of FRF. The A1 neuron preferred large DA when the sound energy fell into FRF with the relatively large inhibitory-subfield, while the same cell preferred small DA when it fell into FRF with the relatively small inhibitory-subfield. It is concluded that the A1 neuron can estimate steepness of slope of a spectral peak, and that a preference for steep slopes stems from a shift of balance toward the spectral inhibition, whereas a preference for gentle slopes, toward the spectral excitation.  相似文献   
58.
Epidemiologic studies of endemic foci of amyotrophic lateral sclerosis (ALS) have shown low concentrations of Ca/Mg and high concentrations of Al/Mn in the drinking water and garden soil, which may play a causative role in the pathogenesis of endemic ALS. We studied the effects of chronic exposure to a low-Ca/Mg high-Al maltol diet on the skin of experimental animals. In ALS patients, atrophy of the epidermis, edematous changes with separated collagen fibrils and an accumulation of amorphous materials between collagen bundles were regarded as pathognomonic skin changes of ALS. Mice chronically fed a low-Ca/Mg high-Al maltol diet showed neuronal degeneration and loss in the spinal cords and cerebral cortices, as well as skin changes including atrophy, separation of collagen fibrils and accumulation of amorphous materials, similar to the skin changes characteristic of ALS. This is the first report of skin changes in animal models similar to those of ALS. We speculate that environmental factors such as chronic low-Ca/Mg high-Al condition play some causative role in the pathogenesis of Kii-ALS.  相似文献   
59.
Gustatory testing using the whole-mouth method was performed in 123 healthy young male and female subjects. The average thresholds for detection and recognition of the four basic tastes were not greatly different from the normal thresholds previously reported in Japan: a 0.0165 M solution of sucrose for sweet taste, a 0.0316 M solution of table salt for salty taste, a 0.000743 M solution of tartaric acid for sour taste and a 0.0000203 M solution of quinine hydrochloride for bitter taste. These results indicate that the whole-mouth gustatory test procedure employed in this study may be useful for evaluating gustatory function clinically. Principal components analysis confirmed that sweet, salty, sour and bitter are indeed the four basic tastes and revealed that the sensation of taste is detected before the specific taste is recognized, regardless of the specific taste tested.  相似文献   
60.
Taste detection and recognition thresholds for the 4 basic tastes were measured in 670 healthy subjects using a new whole-mouth method in which test solutions of the 4 basic tastes were diluted 1:1 with distilled water successively in 13 steps. The taste thresholds were measured by spraying a 1 ml aliquot of solution into the mouth, starting with the lowest concentration, and asking the subject to swallow and note if a taste was detected and, if so, which one. The mouth was rinsed with distilled water only between different taste test solutions. Multiple comparison analysis showed a clear age-related increase in thresholds for salty, sour and bitter tastes for subjects in their eighth decade of life. From the third decade onwards, female subjects had significantly lower thresholds compared to males for sour taste in about half of the age groups and for salty and bitter tastes in some age groups. In contrast, for 18- and 19-year-old subjects, the gustatory thresholds of male subjects were lower than those of female subjects. Regarding smoking, male smokers in their third decade had significantly higher thresholds for bitter taste compared to male non-smokers in this age group.  相似文献   
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