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11.
This paper presents evidence that L-tyrosine oxidation products and 5,6-dihydroxyindole, an intermediate of melanin synthesis bind to and modify DNA structure, as tested by extracting cell DNA, using topoisomerase I and denaturation assays. When supercoiled plasmid pCU18 or pBR322 DNAs are treated with 5,6-dihydroxyindole the supercoiled species disappear and are converted to species less mobile in a gel retardation test with respect to relaxed DNA. 5,6-Dihydroxyindole causes an easier acid denaturation of the double helix. The results, that are dose dependent,would point to both intercalation and cross-linking of DNA by 5,6-dihydroxyindole and its oxidation product(s). 3H-L-tyrosine deriving radioactivity, bound to nuclear DNA, is higher at low pH, (5.6) if compared to pH 6.8. The highest radioactivity bound to cell DNA is found during the transition from the amelanotic to the melanotic phenotype in human melanoma cell lines. As a control, the binding of 3H-L-tyrosine radioactivity to human prostate fibroblast DNA was investigated.  相似文献   
12.
Secretory breast carcinoma is a rare tumor originally described in children and adolescent women with a characteristic morphology and a controversial choice of treatment. We report an additional case of a 4-year-old girl with a breast tumor diagnosed as a secretory carcinoma without involvement of the axillary lymph nodes. The therapy consisted of simple mastectomy and low axillary dissection. She presented with a local recurrence near the surgical scar 8 months later, and a wide elliptical excision of the scar and underlying tissue was performed with subsequent radiotherapy of the surgical bed. This tumor has a relatively benign behavior and rarely metastasizes. A literature review revealed only 22 cases of breast carcinoma in childhood and adolescence. ▪  相似文献   
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Miniaturization of analytical procedures has a significant impact on diagnostic testing since it provides several advantages such as: reduced sample and reagent consumption, shorter analysis time and less sample handling. Lab-on-a-chip (LoC), usually silicon, glass, or silicon-glass, or polymer disposable cartridges, which are produced using techniques inherited from the microelectronics industry, could perform and integrate the operations needed to carry out biochemical analysis through the mechanical realization of a dedicated instrument.Analytical devices based on miniaturized platforms like LoC may provide an important contribution to the diagnosis of high prevalence and rare diseases. In this paper we review some of the uses of Lab-on-a-chip in the clinical diagnostics of immune-mediated diseases and we provide an overview of how specific applications of these technologies could improve and simplify several complex diagnostic procedures.  相似文献   
15.
Angelman syndrome is a neurogenetic disorder that severely affects global neurodevelopment due to modifications in the structure or functioning of UBE3A gene. Its prevalence ranges from 1:10,000 to 1:40,000. There are four main genetic types of AS transmission. A maternal deletion in 15q11.2-q13 is the most common type. There are three well-established electroencephalogram (EEG) patterns used as an ancillary tool for AS diagnosis. The main objectives are to scrutinize the EEG patterns in Angelman syndrome, their correlation to different types of seizures and to review the role of the EEG as an ancillary screening tool in the diagnosis of clinically suspected patients. Forty-three patients’ charts and their previously recorded EEGs were reviewed. A set of 34 patients with deletion type, paternal uniparental disomy type and imprint defect type AS were enrolled. AS diagnosis was confirmed either by fluorescent in situ hybridization test or Methylation Specific–Multiplex Ligation Probe Amplification test. Sequencing of UBE3A was not available. Frequencies and Chi-square tests were used for statistic analysis. Pattern I type EEG was observed in 22 (64.7 %) individuals. Pattern II accounted for 6 (17.6 %); Pattern III was evident in 11 (32.4 %). The three distinguished EEG patterns, more frequently Pattern I, when observed in the appropriate clinical setting, may heighten the index of suspicion for selecting patients who will need a molecular biology test to confirm the diagnosis of AS.  相似文献   
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Abstract

We report on a series of 48 patients, ages 74 to 20 year, with hypophyseal adenomas. Of these, 46 (96%) had secreting tumors, 3 had Cushing’s disease, 9 had somatotrophinomas, and 34 (29 females and 5 males) had prolactinomas. Thirty cases were diagnosed as intrasellar adenomas (62%) while the remaining eighteen (38%) presented extrasellar expansion. Of 9 acromegalic patients, 7 had typical clinical and biochemical features while 2 were exclusively prognatic with normal basal GH levels, but abnormal dynamic tests. Prolactinomas were npninvasive in women and faster growing and more extensive in men. Forty seven patients underwent surgery. Five of these required craniotomy and the rest were approached through the sphenoidal bone (TSf). Remission was achieved in Cushing’s disease, acromegaly, and female intrasellar prolactinomas. Larger tumors such as nonsecreting adenomas and male prolactinomas showed poor results after undergoing subtotal resections, with persistance of endocrinological disturbances. From our findings it appears that these tumors are not more aggressive in youths than in adults. Because there was a close relationship between tumor size, invasiveness, and the patients, final outcome, we conclude that early diagnosis and treatment is essential. Frequent complaints in adolescents such as irregular menses, retarded puberty, and growth disorders should be thoroughly investigated and not merely considered as transient or ‘functional’ [Neural Res 1998; 20: 415–417]  相似文献   
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19.

Purpose  

To analyse results of combined treatment of adjuvant radio-chemotherapy (RT-CT) in patients diagnosed with gallbladder cancer (GBC) after complete resection. Methods and material From June 1993 until July 2006, 67 patients with a diagnosis of GBC who underwent R0 surgical resection and were staged as T1b-2-3N0-1M0 received adjuvant RT-CT. Radiotherapy consisted of whole abdominal irradiation (20 Gy at 100 cGy daily) plus a boost to the tumour bed for a total of 45–59.4 Gy. Concomitant chemotherapy (fluoropyrimidines) was given. Overall survival (OS) and median survival were analysed in relation to different prognostic factors.  相似文献   
20.

Objective

To compare the effects of classic progressive resistance training (PRT) versus eccentric strength-enhanced training (EST) on the performance of functional tests and different strength manifestations in the lower limb of people with multiple sclerosis (PwMS).

Design

Experimental trial.

Setting

Strength training program.

Participants

PwMS (N=52; 19 men, 33 women) belonging to MS associations from the Castilla y León, Spain.

Interventions

Participants were assigned to 1 of 2 groups: a control group that performed PRT or an experimental group that performed EST. In both groups, the knee extensor muscles were trained for 12 weeks.

Main Outcome Measures

Before and after 12 weeks of training, maximal voluntary isometric contraction and 1 repetition maximum (1RM) of the knee extensors were evaluated, as were the Chair Stand Test (CST) and Timed 8-Foot Up and Go (TUG) functional tests.

Results

No differences were found between the groups in the initial values for different tests. Intragroup comparisons found significant differences in CST (F=69.4; P<.001), TUG (F=40.0; P<.001), and 1RM (F=57.8; P<.001). For intergroup comparisons, EST presented better results than PRT in the CST (EST, 4.7%±2.8%; PRT, 1.9%±2.8%; F=13.1; P=.001) and TUG (EST, ?2.9±4.7; PRT, ?.41±5.6; F=5.6; P=.022).

Conclusions

In PwMS, EST leads to improvements in 1RM, TUG, and CST that are similar to those of PRT. However, for patients who participated in this study, the EST seems to promote a better transfer of strength adaptations to the functional tests, which are closer to daily-living activities.  相似文献   
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