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61.

Introduction

Cone-beam computed tomographic (CBCT) imaging is a valuable tool for endodontic therapy. The aim of this study was to verify whether clinical use of CBCT imaging can accurately acquire parameters concerning molar pulp chamber landmarks, which are important data to help start a successful access cavity and avoid iatrogenic furcation perforations.

Methods

Seventy CBCT images were used to measure 118 maxillary and 104 mandibular molars. The following vertical distances were measured: from the cusp tip/central fossa to the pulp chamber floor, to the pulp chamber ceiling, and to furcation; from the pulp chamber ceiling to furcation; from the pulp chamber floor to furcation; and the pulp chamber height. Measurements were read to the nearest 0.05 mm.

Results

The measurements were as follows: the pulp chamber floor to furcation (maxillary molar: 1.97 ± 0.58 [mean ± standard deviation, mm], mandibular molar: 2.24 ± 0.47), the pulp chamber ceiling to furcation (maxillary molar: 4.09 ± 0.68, mandibular molar: 3.78 ± 0.70), the central fossa to furcation (maxillary molar: 8.78 ± 0.79, mandibular molar: 8.53 ± 0.65), the central fossa to the pulp chamber floor (maxillary molar: 6.81 ± 0.83, mandibular molar: 6.29 ± 0.65), the central fossa to the pulp chamber ceiling (maxillary molar: 4.69 ± 0.59, mandibular molar: 4.75 ± 0.56); and pulp chamber height (maxillary molar: 2.12 ± 0.81, mandibular molar: 1.53 ± 0.68). Measurements showing the least standard deviation were the central fossa to furcation and the central fossa to the pulp chamber floor.

Conclusions

CBCT imaging may be used for precise clinical acquisition of the pulp chamber landmark measurements for molars thereby facilitating successful access cavity.  相似文献   
62.
The effects of mitragynine on anxiety-related behaviours in the open-field and elevated plus-maze tests were evaluated. Male Sprague–Dawley rats were orally treated with mitragynine (10, 20 and 40 mg/kg) or diazepam (10 mg/kg) 60 min before behavioural testing. Mitragynine doses used in this study were selected on the basis of approximately human equivalent doses with reference to our previous literature reports. Acute administration of mitragynine (10, 20 and 40 mg/kg) or diazepam (10 mg/kg) increased central zone and open arms exploration in the open-field and elevated plus-maze tests respectively. These anxiolytic-like effects of mitragynine were effectively antagonized by intraperitoneal administration of naloxone (2 mg/kg), flumazenil (10 mg/kg), sulpiride (0.5 mg/kg) or SCH 23390 (0.02 mg/kg) 15 min before mitragynine treatments. These findings reveal that the acute administration of mitragynine produces anxiolytic-like effects and this could be possibly attributed to the interactions among opioidergic, GABAergic and dopaminergic systems in brain regions involved in anxiety.  相似文献   
63.
The inorganic stannous-based perovskite oxide SrSnO3 has been utilized in various optoelectronic applications. Facilitating the synthesis process and engineering its properties, however, are still considered challenging due to several aspects. This paper reports on a thorough investigation of the influence of rare-earth (praseodymium) doping on the microstructural and optoelectronic properties of pure and Pr-doped SrSnO3 perovskite oxide thin films synthesized by a two-step simple chemical solution deposition route. Structural analysis indicated the high quality of the obtained phase and the alteration generated from the insertion of impurities. Surface scanning illustrated the formation of homogenous and crack-free SrSnO3 thin films with a nanorod morphology, with an augmentation in size as the dopant ratios increased. Optical properties analysis showed an enhancement in the samples optical absorption with wide-range bandgap tuning. First-principles calculations revealed the exchange interactions between the 3d–4f states and their impact on the electronic properties of the pristine material. Hall-effect measurements revealed an immense decrement in the resistivity of the films upon increment of doping ratios, passing from 7.3 × 10−2 Ω cm for the undoped sample to 4.8 × 10−2 Ω cm for 7% Pr content, while a reverse trend was observed on the carrier mobility, rising from 2.5 to 7.6 cm2 V−1 s−1 for 7% Pr content. The results emphasized the efficiency of the simple synthesis route to produce high-quality samples. The current findings will contribute to paving the way towards expanding the utilization of simple and cost-effective chemical solution deposition methods for the fast and large area growth of stannous-based perovskite oxides for optoelectronic applications.

Unraveling the optical, electronic and electrical properties of high-quality nanorod morphology spray-coated Pr-doped SrSnO3 perovskite oxide thin films.  相似文献   
64.
Delafossite materials are considered to be a promising range of transparent conductive oxides for optoelectronic applications. The complications that have held back their implementation in practical devices lie in the complex growth methods that are required and in the formation of undesirable secondary phases. Herein, a fast, simple, and low-cost deposition method allowing the deposition of high-quality 2H-CuFeO2 nanostructured thin films is employed. The effect of Sr doping on the properties of spray-coated CuFeO2 thin film annealed at 850 °C is reported. X-ray diffraction (XRD) analysis revealed the delafossite structures of all the samples corresponding to the 2H-CuFeO2 phase. The lattice spacing decreased with increasing substitution of Sr at the Cu site. Raman analysis further authenticated the structural results collected via XRD analysis. Surface scanning using field-emission scanning electron microscopy revealed the formation of nanostructured CuFeO2 thin film possessing high crystalline quality, with the nanocrystal size increasing as the dopant content was increased. Energy-dispersive X-ray analysis allowed the quantification of the elements content via determining the ratios of the main elements as well as the dopant content in each sample. The optical properties of the samples showed strong light absorption in the visible region with a decrease in the band gap values with Sr insertion. First-principles calculations using density functional theory (DFT) were conducted to strengthen the experimental findings regarding the nature of the bonds in the hexagonal lattice of the CuFeO2 compound and the effect of Sr doping on its characteristics. The electrical properties measured at room temperature revealed p-type conductivity with tunable resistivity, while the samples displayed increased electron mobility as a function of the dopant content. Consequently, our work introduced an efficient and cost-effective synthesis route for the preparation of high-quality nanostructured 2H-CuFeO2 thin films, paving the way to facilitate further device applications.

Facile synthesis of the challenging 2H-CuFeO2 delafossite nanostructured thin films is reported, and the effect of Sr doping is revealed experimentally and theoretically.  相似文献   
65.
The aim of the present study was, first, to evaluate the prognostic value of mid-regional proadrenomedullin (proADM) in emergency department (ED) patients with a diagnosis of community acquired pneumonia (CAP) and, second, to analyze the added value of proADM as a risk stratification tool in comparison with other biomarkers and clinical severity scores.  相似文献   
66.
Posterior reversible encephalopathy syndrome is a rare underestimated condition, that generally complicates a rise in blood pressure in an acute setting. This entity has been increasingly identified in patients with systemic lupus erythematosus disease. PRES is challenging to diagnose seeing as it presents with nonspecific neurological symptoms, such as head-aches, confusion, seizures, visual changes or a coma, and can mimic neuropsychiatric lupus. Imaging plays a necessary role in confirming this diagnosis, as it is characterized by vasogenic edema of the posterior white matter, in which the distribution is bilateral and symmetrical. Although this syndrome is rare, early diagnosis allows a prompt treatment and therefore a favorable outcome. We present a case report of PRES in a 14-year-old female previously diagnosed with lupus nephropathy, who presented to the emergency department with seizures and uncontrolled hypertension, that was unfortunately not reversible is this patient.  相似文献   
67.

Background

Celiac trunk encasement by adenocarcinoma of the pancreatic body is generally regarded as a contraindication for surgical resection. Recent studies have suggested that a subset of stage III patients will succumb to their disease in the absence of distant metastases. We hypothesized that patients with stage III tumors invading the celiac trunk, who are free of distant disease following neoadjuvant therapy, may derive prolonged survival benefit from aggressive surgical resection.

Methods

We performed a retrospective review of distal pancreatectomies with en bloc celiac axis resection for pancreatic adenocarcinoma.

Results

Eleven patients underwent a distal pancreatectomy with en bloc celiac axis resection after completing neoadjuvant chemoradiation therapy. Median operative time was 8?h, 14?min, and median estimated blood loss was 700?ml. Median length of stay was 9?days. Five patients (45%) had postoperative complications; three were Clavien grade I. Four patients (35%) had pancreatic leaks; two were ISGPF grade B, and two were grade A. There were two 90-day perioperative deaths. Ten patients had R0 resections (91%). After a median follow-up of 41?weeks, six patients recurred. Four of the five patients with SMAD4 loss recurred, and two of the five patients with intact SMAD4 recurred. Median disease-free and overall survival were 21?weeks and 26?months, respectively.

Conclusions

Resection of pancreatic body adenocarcinoma with celiac axis resection is technically feasible with acceptable perioperative morbidity and mortality.  相似文献   
68.
69.
Flow of an electrically conducting fluid characterizing blood through the arteries having irregular shaped multi-stenoses in the environment of a uniform transverse magnetic-field is analysed. The flow is considered to be axisymmetric with an outline of the irregular stenoses obtained from a three-dimensional casting of a mild stenosed artery, so that the physical problem becomes more realistic from the physiological point of view. The marker and cell (MAC) and successive-over-relaxation (SOR) methods are respectively used to solve the governing unsteady magnetohydrodynamic (MHD) equations and pressure-Poisson equation quantitatively and to observe the flow separation. The results obtained show that the flow separates mostly towards the downstream of the multi-stenoses. However, the flow separation region keeps on shrinking with the increasing intensity of the magnetic-field which completely disappears with sufficiently large value of the Hartmann number. The present observations certainly have some clinical implications relating to magnetotherapy which help reducing the complex flow separation zones causing flow disorder leading to the formation and progression of the arterial diseases.  相似文献   
70.
Sleep behaviour has been extensively studied with questionnaires in industrialised countries to investigate the epidemiology of sleep-wake disorders. However, only few attempts have yet been made to examine sleep behaviour of people living in Africa. Although, a large number of studies in hot or cold environments have used short-term exposures, reporting disrupted sleep for most of them, long-term exposures to stressful thermal environments are rare in the literature. Prior to the present investigation, we used questionnaires to analyse the effects of seasonal heat increase on perceived sleep behaviour and sleep quality in young native African students in Niger [7], even though these methods of investigation are by no means as accurate as polysomnographic recordings. The hypothesis was that sleep behaviour may be influenced by climatic variations in a hot dry tropical climate. Such climatic variations have been shown to induce seasonal heat acclimatisation marked by changes in body temperature rhythms in the hot versus the cool season [13]. Sleep behaviour was examined during two 7-day periods in January ("cool-dry" season, 88 subjects) and May ("hot-dry" season, 53 subjects). The questionnaire was completed after night sleep and/or naps. The subjects slept an average of 7 1/2 hours a day, most of them having afternoon naps. They experienced no major seasonal variation in their sleep behaviour, but for an increased number of awakenings during the hot season. Restorative quality of sleep scored lower after a nap than after nocturnal sleep. Therefore, general sleep characteristics were not modified by seasonal temperature variations in African native students, perhaps because of the limited changes in daylight under the low latitude of Niamey. Another investigation was carried out using the same 12-item questionnaire in Abidjan on 78 medical students who did not have a nap [9]. Contrary to the Niamey students, the Abidjan subjects adopted short duration sleep schedules, without any effect on the subjective quality of the restorative properties of their sleep.  相似文献   
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