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31.
Previous studies have shown that in vitro exposure to single compounds released from composite resins may induce cell death. In the present study the effects of eluates from commercially available composite resins used for direct or indirect restorations were evaluated on the cell cycle progression and type of cell death of cultured WEHI 13 var fibroblasts. Cells exposed to eluates of the materials were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell death, for cell cycle profiles by flow cytometry, for caspase-3 biochemically and by immunocytochemistry, and for morphological changes by fluorescence microscopy with acridine orange. The direct composite resin eluates induced extensive apoptosis, followed by secondary necrosis. This was accompanied by cell enlargement, micromultinucleation, chromatin disintegration, cell cycle arrest at different phases, and caspase-3 activation. The composites for indirect restorations were much less cytotoxic at all biological end-points investigated. The findings suggest that composite resins used for direct and indirect dental restorations differ in their cytotoxic potential and their ability to affect basic cellular functions. This underlines the impact of improved polymerization with respect to their biologic behavior.  相似文献   
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Benign cardiac tumors are rare; they can present with nonspecific symptoms and represent a diagnostic challenge to the clinician. We describe an interesting case of a 26-year-old female who presented with a 6-month history of cough, breathlessness, palpitations, dizziness, and fever. Despite repeated clinical reviews in the community, diagnosis of cardiac tumor was not made until she developed decompensated cardiac failure with bilateral pleural effusions and pulmonary edema. Echocardiogram revealed an enormous left atrial mass that extended one-third into left ventricle during systole. The patient underwent successful surgical resection with histological confirmation of a benign atrial myxoma.  相似文献   
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Sleep and Breathing - The presence of comorbid insomnia and sleep apnea (COMISA) reduces the initial acceptance of continuous positive airway pressure (CPAP) therapy in 39–58% of patients...  相似文献   
37.
ALOX5 is implicated in chronic myeloid leukemia development in mouse leukemic stem cells, but its importance in human chronic myeloid leukemia is unknown. Functional ALOX5 was assessed using an LTB4 ELISA and ALOX5, and LTB4R1 mRNA expression was determined via a TaqMan gene expression assay. LTB4R1 and 5-LOX protein levels were assessed by cell surface flow cytometry analysis. At diagnosis ALOX5 was below normal in both blood and CD34+ stem cells in all patients. On treatment initiation, ALOX5 levels increased in all patients except those who were destined to progress subsequently to blast crisis. LTB4 levels were increased despite low ALOX5 expression, suggesting that the arachidonic acid pathway is functioning normally up to the point of LTB4 production. However, the LTB4 receptor (BLT1) protein in newly diagnosed patients was significantly lower than after a period of treatment (P<0.0001). The low level of LTB4R1 at diagnosis explains the downregulation of ALOX5. In the absence of LTB4R1, the arachidonic acid pathway intermediates (5-HEPTE and LTA4) negatively regulate ALOX5. ALOX5 regulation is aberrant in chronic myeloid leukemia patients and may not be important for the development of the disease. Our data suggest caution when extrapolating mouse model data into human chronic myeloid leukemia.  相似文献   
38.
Long term fire retardant (LTR) application for forest fire prevention purposes as well as wildland fires can result in chemical leaching from forest soils. Large quantities of sodium (Na), aluminium (Al), iron (Fe), manganese (Mn), copper (Cu) and silicon (Si) in leachates, mainly due to ammonium (one of the major LTR components) soil deposition, could affect the groundwater quality. The leaching of Na, Al, Fe, Mn, Cu and Si due to nitrogen based LTR application (Fire Trol 931) was studied at laboratory scale. The concentrations of Na+, Al3+, Fe3+/Fe2+, Mn2+, Cu2+ and Si4+ were measured in the resulting leachates from pots with forest soil and pine trees alone and in combination with fire. The leaching of Na, Fe and Si from treated pots was significantly greater than that from control pots. The leaching of Al, Mn and Cu was extremely low.  相似文献   
39.
Nicotine, a major psychoactive component of tobacco smoke, increases glutamate transmission in the nucleus accumbens (NAcc). However, the role of the N‐methyl‐D‐aspartate (NMDA)‐mediated glutamatergic neurotransmission in the NAcc shell and core subdivisions in nicotine‐dependent behaviors has not been studied. The present study evaluated, in rats, the effects of bilateral administration of the competitive NMDA receptor antagonist LY235959 (0, 0.1, 1, and 10 ng/0.5 μL/side) into the NAcc shell or core on intravenous nicotine (fixed‐ and progressive‐ratio schedules) and food (fixed‐ratio schedule) self‐administration, and cue‐induced reinstatement of nicotine‐seeking behavior. In addition, the effects of LY235959 injections in the NAcc shell were evaluated on nicotine‐induced conditioned taste aversion, a procedure that assesses the aversive effects of nicotine. LY235959 injections into the NAcc shell significantly increased nicotine self‐administration under both fixed‐ and progressive‐ratio schedules, and decreased food self‐administration, but had no effect on nicotine‐induced conditioned taste aversion or cue‐induced nicotine seeking. Furthermore, injections of LY235959 in the lateral septal nucleus, originally intended as an anatomical control site for the NAcc shell, increased nicotine self‐administration and decreased food self‐administration under the fixed‐ratio schedule. In contrast, LY235959 injections into the NAcc core increased the cue‐induced reinstatement of nicotine seeking and decreased food self‐administration, but had no effect on nicotine self‐administration. The present data suggest that NMDA receptor‐mediated glutamatergic neurotransmission in the NAcc shell and core differentially regulates food‐ and nicotine‐maintained responding. Importantly, the data suggest an inhibitory role for NMDA‐mediated glutamatergic neurotransmission in the NAcc shell and core in nicotine self‐administration and the cue‐induced reinstatement of nicotine seeking, respectively.  相似文献   
40.

Background

Insufficient data exist regarding postoperative thoracic epidural analgesia for morbidly obese patients undergoing open bariatric surgery. This study evaluated the effectiveness of morphine loading in a postoperative thoracic epidural analgesic regimen of patient-controlled epidural analgesia (PCEA) with levobupivacaine combined with continuously administered epidural morphine in this patient group.

Methods

In this prospective randomized controlled trial, 48 superobese patients (body mass index of ≥50 kg/m2) undergoing open bariatric surgery were randomly allocated to three groups of 16 patients each. Postoperatively, all groups received a continuous epidural morphine infusion of 0.2 mg/h with 0.1 % levobupivacaine via PCEA. Group A did not receive intraoperative epidural morphine loading, while groups B and C received an intraoperative 1- and 2-mg morphine bolus, respectively. Levobupivacaine consumption via PCEA (primary outcome), pain scores at rest and on cough, the time to return of bowel function and ambulation, and arterial blood gas levels (secondary outcomes) were recorded.

Results

The increase in perioperative morphine administration (groups B and C) led to a significantly prolonged return to normal bowel function and delayed ambulation (P?Conclusions Thoracic PCEA with 0.1 % levobupivacaine combined with continuous epidural morphine administration of 0.2 mg/h without morphine loading is an effective postoperative analgesic regimen that provides adequate pain control, early ambulation, and early return of bowel function in superobese patients, particularly those with OSA.  相似文献   
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