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991.
992.
The Helicobacter pylori infection rate was determined in 124 consecutive patients with duodenal ulcers (DU), gastric ulcers (GU), duodenal erosions or gastric erosions diagnosed by endoscopy at a single institution in north-eastern peninsular Malaysia in 1996-97. Biopsies of the gastric antrum and body were subjected to the urease test, Gram staining of impression smears, culture and histopathological examination. Serology was undertaken on all patients using a locally validated commercial kit. Infection was defined as a positive result in at least one test. The infection rates were 20% (10/50), 21.2% (7/33), 16.7% (1/6) and 17.1% (6/35) in DU, GU, duodenal erosion and gastric erosion patients, respectively. The infection rate among Malays [7.0%, (6/86)] was lower than in non-Malays [47.4% (18/38)] (P < 0.001). There was a higher infection rate among males, who constituted 62.1% (77/124) of the sample. Seventy-eight patients (62.9%) were receiving non-steroidal anti-inflammatory drugs (NSAIDs) and 33 patients (26.6%) were neither receiving NSAIDs nor were infected with H. pylori. The H. pylori infection rate among peptic ulcer patients in this predominantly Malay rural population appears to be the lowest reported in the world thus far. Empirical H. pylori eradication therapy in peptic ulcer patients is clearly not indicated in this community. The possible reasons for the low prevalence of H. pylori infection are discussed.  相似文献   
993.
A 1H NMR procedure for the monitoring of ampicillin (Amp) and its main related substance in different media, has been developed. The characteristics peak of Amp, 6-aminopenicillanic acid (6-APA), phenylglycine (PhG), and penicilloic acid in the range of 0.5-0.9 and 3.0-4.5 ppm were used for their identification in drugs and serum samples. The quantitative works were performed based on the intensity of protons of the methyl group link to the beta-lactam cyclic of Amp and 6-APA and the aromatic protons of PhG relative to the protons of methylene group of maleic acid, as internal standard, at constant temperature. The resulting data are compared with those obtained with an HPLC method proposed by British Pharmacopoeia. Statistical studies show that, at a confidence limit of %95, there is no significant difference between the two methods. In comparison with the HPLC method, the proposed NMR method does not require any sample pretreatment, standard solution preparation, long analysis time and use of any carcinogenic solvent. The method was applied to the determination of Amp and its related substances in synthetic mixtures, drug powders and serum samples.  相似文献   
994.
AIM:To identify current trends in anaesthesia technique for cataract surgery and make this information available to ophthalmologists.METHODS:An electronic survey was created and distributed to members of online ophthalmology forums;results were subsequently analysed in spreadsheet software.RESULTS:In total there were 71 completed surveys.The most preferred anaesthesia technique in cataract cases was topical anaesthesia with intracameral injection(n=34,47.9%),and the least preferred techniques were retrobulbar(n=1,1.4%) and peribulbar blocks(n=1,1.4%).The most commonly preferred local anaesthetic was lidocaine 2%(n=41,57.7%).CONCLUSION:Topical anaesthesia techniques with lidocaine 2% appear to be the most preferred method of anaesthesia in cataract surgery in our survey.Compared with previous literature our survey shows that topical anaesthesia is being increasingly used in cataract surgery,especially in conjunction with intracameral injection.The predominant reasons for this seem to be patient comfort and ease of technique.  相似文献   
995.
We describe a patient with proliferative diabetic retinopathy who had laser in situ keratomileusis (LASIK). Rapid progression and pronounced aggravation of diabetic retinopathy occurred after LASIK, resulting in severe visual loss in both eyes.  相似文献   
996.
Neurophysiological processes underlying auditory memory and attention are impaired in habitually short sleepers. The aim of this study was to use dynamic causal modeling (DCM) to study the mechanisms of these impairments in short sleepers. Eight normal sleepers (total sleep time (TST)=7-8h) and nine habitual short sleepers (TST≤6h) participated. The time in bed was increased from habitual (≤6h) to extended (~8.5h) for one week in the short sleep group. Event related potentials (ERPs) were collected using an auditory novelty task in "IGNORE" and "ATTEND" conditions. Fourteen DCM models were considered using different configurations of connections among the following six areas: left and right primary auditory cortices, superior temporal gyri (STG), and inferior temporal gyri (IFG). After fitting the ERPs to the 14 models (separately for the IGNORE and ATTEND conditions), the best model (across subjects) was chosen using the Bayesian model comparison. For both conditions, the connection from right-STG to right-IFG for normal sleepers was significantly greater than habitual short sleepers. This connection did not differ in habitual short sleepers before and after one week of extended sleep time. This connection for normal sleepers was not significantly greater than the habitual short sleepers after one week of extended sleep. These results show that the deficiency of novelty processing, seen in short sleepers, can be explained by the differences in connectivity of the pathway between frontal and temporal brain areas as compared to the normal sleepers. In addition, one week of extended time in bed was not enough to fully normalize this neuronal pathway between STG and IFG in short sleepers.  相似文献   
997.
Goals and objectivesThis study was designed to evaluate the effects of exogenous Sodium-Hyaluronate (NaH) on full thickness Superficial Digital Flexor Tendon (SDFT) rupture in the early phase of healing in rabbits.MethodsForty White New Zealand mature male rabbits were randomly divided into two equal groups of injured treated and injured untreated. After full thickness tendon transection and surgical repair, using modified Kessler technique and running suture, the injured legs were casted for 14 days. Sodium-Hyaluronate was injected subcutaneously over the lesion on days 3, 7 and 10 post-injury (DPI). The control animals received normal saline injection following the same protocol. Weight of the animals, tendon diameter, ultrasonographic evaluations was conducted at weekly intervals. The rabbits were euthanized on 28 DPI and the tendons were assessed for macroscopic, histopathologic, ultrastructural, and percentage dry weight analysis.ResultsAlthough there was no significant difference in the radiographs of the treated and untreated lesions, treatment significantly reduced tendon diameter, ultimate and yield strain and increased echogenicity and dry weight content of the injured tendons compared to those of the untreated ones. Treatment also significantly enhanced the maturation rate of the tenoblasts, diameter and density of the collagen fibrils.ConclusionTreatment of NaH has been shown to be effective in restoring the morphological and biomechanical properties of lacerated SDFT of rabbits and may be valuable in the clinical trial studies.  相似文献   
998.
Bioluminescence Tomography attempts to quantify 3-dimensional luminophore distributions from surface measurements of the light distribution. The reconstruction problem is typically severely under-determined due to the number and location of measurements, but in certain cases the molecules or cells of interest form localised clusters, resulting in a distribution of luminophores that is spatially sparse. A Conjugate Gradient-based reconstruction algorithm using Compressive Sensing was designed to take advantage of this sparsity, using a multistage sparsity reduction approach to remove the need to choose sparsity weighting a priori. Numerical simulations were used to examine the effect of noise on reconstruction accuracy. Tomographic bioluminescence measurements of a Caliper XPM-2 Phantom Mouse were acquired and reconstructions from simulation and this experimental data show that Compressive Sensing-based reconstruction is superior to standard reconstruction techniques, particularly in the presence of noise.OCIS codes: (170.3010) Image reconstruction techniques, (170.6280) Spectroscopy, fluorescence and luminescence, (170.6960) Tomography  相似文献   
999.
1000.

Introduction

The optimal treatment of cervicofacial nontuberculous mycobacterium lymphadenitis (CFNTB) in children is yet to be established. There is a general consensus that surgical excision results in a definitive resolution of the disease. The main aim of surgery is to remove affected nodes so that they do not discharge through the skin. Recently there are some investigators who are reporting successful antibiotic treatment and advocating medical therapy as the first line treatment.

Methods

16 children consecutively presenting to otolaryngology in a tertiary referral centre over an 8-year period with CFNTB. Inclusion criteria were chronic cervicofacial lymphadenitis with either: (1) a culture positive for atypical mycobacteria (from either a lymph node or fine needle aspirate (FNA) specimen); or (2) acid-fast bacilli identified (from either a lymph node or FNA specimen); or (3) post excision histological findings consistent with mycobacterial infection (i.e. non-caseating granulomas) in the absence of other clinical features suggestive of other granulomatous conditions. Lesions with superficial skin change were treated preferentially with surgery. Children presenting with lymph nodes contained deep to sternocleidmastoid were assessed with FNA cytological and microbiological analysis and MRI or CT, and treated preferentially with antibiotics or watchful waiting.

Results

4 children (2 culture positive, 2 with acid-fast bacilli on needle aspirate) presented with lymphadenopathy deep to sternocleidmastoid and were managed non-surgically. All 4 resolved without cutaneous involvement. 11 children with a clinical presentation of CFNTB underwent complete excision of all involved nodes for superficial lesions (6 were culture positive, and all had granulomatous histology). None recurred. 1 patient presented late with a mature, discharging parotid sinus, which was managed with watchful waiting as the lesion was clinically close to natural resolution.

Conclusions

Depth at presentation may help decide which patients with CFNTB can be treated non-surgically without cutaneous sequelae. We propose that a watch and wait management is an option for deep nodes.  相似文献   
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