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22.
Aquaporins are water selective channels which play important roles in cell volume regulation during the transmission of spermatozoa to female tract. This study investigated the expression of aquaporin3 and determined the role of aquaporins in human sperm motility and mitochondrial membrane potential (MMP). RT-PCR and flow cytometry analysis were done to investigate aquaporin3 expression levels, and immunolocalisation of aquaporin3 in the spermatozoa was detected using immunocytochemical analysis. The sperm suspension was divided into four groups of spermatozoa: (a) Spermatozoa at 0 hr, (b) spermatozoa in control group, (c) spermatozoa treated with HgCl2 (as an aquaporin inhibitor) and (d) spermatozoa treated with HgCl2+ and 2-mercaptoethanol. The sperm samples were examined in terms of sperm motility and mitochondrial membrane potential. Results confirmed aquaporin3 expression in human spermatozoa and immunocytochemistry results showed an intense immunoreactivity in whole sperm tail. After 60 min, HgCl2 showed a significant decrease in motility and MMP compared to the control group. At this time point, 2-mercaptoethanol in the HgCl2+ 2-mercaptoethanol group reversed the effects of HgCl2 as compared to the HgCl2 group. Present study showed the expression and immunolocalisation of AQP3 in human spermatozoa and the potential role of AQPs in the sperm motility and MMP.  相似文献   
23.

Background

Phthalate, esters of phthalic acid, are mainly applied as plasticizers and cause several human health and environment hazards. The essential oils of Achillea species have attracted a great concern, since several biological activities have been reported from varieties of these medicinal species. On the other side, due to the problems regarding the waste disposal in developing countries, phthalate derivatives can easily release from waste disposal to the water and soil resulting in probable absorption and accumulation by medicinal and dietary plants. As a matter of fact, although the toxicity of phthalate derivatives in human is well-known, food crops and medicinal plants have been exposing to phthalates that can be detected in their extracts and essential oils. Achillea tenuifolia (Compositea) is one of these herbaceous plants with traditional applications which widely growing in Iran.

Finding

The plant root was subjected to hydro-distillation for 4 h using Clevenger type apparatus to obtain its essential oil before and after acid treatment. Both of the hydro-distilled essential oils were analysed by GC-MS method resulted in recognition of their constituent. Phthalate contamination as (1, 2-benzenedicarboxylic acid, bis (2-methylpropyl) ester (5.4%) and phthalic acid (4.5%), were identified in the first and second extracted oils, respectively.

Conclusion

As a warning, due to the potential role of phthalates to cause reproductive toxicity, disturb of endocrine system and causing cancers, medicinal plants have to be considered through quality control for detection of these compounds.  相似文献   
24.
To assess the daily salt intake of people aged 20-74 years based on the 24-hour urinary sodium excretion in urban population of Yazd, a population-based cross-sectional study was conducted. This is a substudy of Yazd Healthy Heart Project in Iran. From 2004 to 2005, two thousand people of the urban population of Yazd city, aged 20-74 years, were enrolled in the main study. Overall, 219 volunteer participants of 20-70 years were enrolled in this substudy. Sample frame was the household numbers according to the database of Yazd City Health Services. Calcium, phosphorus, sodium, potassium, and creatinine were measured in the urine samples collected from the participants over a 24-hour period. Sodium content in urine over 24 hours was 171.7±82.9 mmol/day in males and 127.8±56.1 mmol/day in females (p<0.0001) while potassium content was 49.4±23.2 mmol/day in males and 41.5±25.1 mmol/day in females (p=0.2). Estimated average daily salt (NaCl) intake was 10.0±4.8 g/day in males and 7.5±3.3 g/day in females (p<0.0001). Only one participant had the ideal Na/K ratio of less than one. Na/K ratios greater than one and less than two were seen in 11.3% (n=24), and a ratio equal to or greater than 2 was observed in 82.3% (n=118) of the participants. The average Na/K ratio was 3.69±1.58. Unlike many developed countries where sodium intake declined over the past few decades, the daily sodium intake in Yazd is high, and daily potassium intake is low. This is similar to what was observed four decades ago in an area not far from Yazd. Efforts must be directed towards health promotion interventions to increase public awareness to reduce sodium intake and increase potassium intake.Key words: 24-hour urine, Blood pressure, Cardiovascular disease, Hypertension, Policy, Potassium, Prevention, Salt, Sodium, Iran  相似文献   
25.

Background

Cavernous malformations (CMs) of the central nervous system (CNS) are angiographically occult vascular lesions that affect approximately 0.5 % of the general population, and one quarter of all CMs occurs in children.

Methods

We retrospectively analyzed demographic, clinical, radiological, management, and follow-up data of 36 pediatric patients with CMs from a single institution.

Results

The mean age of the children at first presentation and at operation was 8.7 and 9.6 years, respectively. However, a bimodal age distribution was found with peak under 4 years and above 12 years. Seizure was the most common single presenting symptom (38.9 %), and 61.1 % of patients had at least one seizure before the admission. Focal neurological deficits (410.7 %), intracranial hypertension (27.8 %), and headache (2.8 %) were the other manifestations. Acute/subacute hemorrhage was evident at presentation in 63.9 %. The patients under 6 years of age were found to have significantly more giant cavernomas (69 vs 20 %; p?=?0.011), and more overt hemorrhages (81 vs 47 %; p?=?0.065) at diagnosis than those patients above 12 years. Surgery was performed in 31 patients (32 CMs), with 26 total and 6 incomplete resections. Mean follow-up duration was 6.9?±?4.1 years. Of all patients, 63.8 % had excellent and 30.5 % had good clinical outcomes, and also 90.9 % of the epileptic patients were seizure-free (Engel Class I) at the last follow-up.

Conclusions

Younger children tend to harbor larger CMs and present with hemorrhage more frequently than older ones. Microsurgical resection should be the treatment of choice in symptomatic and accessible CMs.  相似文献   
26.
Salivary, serum matrix metalloproteinase-8 (MMP-8), tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), neutrophil elastase (NE), and myeloperoxidase (MPO) levels were investigated in generalized chronic periodontitis (GCP), generalized aggressive periodontitis (GAgP), and healthy groups. Whole-mouth clinical periodontal measurements were recorded. Salivary, serum concentrations of MMP-8, MPO, TIMP-1, and NE were determined by immunofluorometric assay or ELISA in 18 patients with GCP, 23 patients with GAgP, 18 individuals with healthy periodontium. Patients in the GAgP group were younger than the other groups (p?p?TIMP-1 concentrations were lower in the periodontitis groups than the controls (p?相似文献   
27.
28.
Dihydronaphthofurans (DHNs) are an important class of arene ring-fused furans which are widely found in many natural and non-natural products and drug candidates with relevant biological and pharmacological activities. Furthermore, vinylidene-naphthofurans exhibit photochromic properties when exposed to UV or sun light at room temperature. For these reasons, a vast array of synthetic procedures for the preparation of dihydronaphthofurans including annulation of naphthols with various reagents, cycloaddition reactions ([3 + 2], [4 + 1] and Diels–Alder), intramolecular transannulation, Friedel–Crafts, Wittig, Claisen rearrangement, neophyl rearrangement and other reactions under various conditions have been developed over the past decades. This review aims to describe the different strategies developed so far for the synthesis of dihydronaphthofurans and their applications. After a brief introduction to the types of dihydronaphthofurans and their biological activities, the different synthetic approaches such as chemical, photochemical, and electrochemical, methods are described and organized on the basis of the catalysts and the other reagents employed in the syntheses. The subsequent section focuses on biological and pharmacological applications and photochromic properties of the target compounds.

Dihydronaphthofurans (DHNs) are an important class of arene ring-fused furans which are widely found in many natural and non-natural products and drug candidates with relevant biological and pharmacological activities.  相似文献   
29.
Donepezil and acetyl cholinesterase inhibitors are the most commonly prescribed medications for the treatment of Alzheimer''s disease. We describe a 2‐year‐old infant who was referred to the emergency department after developing cholinergic syndrome 6 hours after ingesting 10 mg of his grandmother''s donepezil tablets and was finally discharged in stable condition.  相似文献   
30.
Journal of Molecular Neuroscience - Alzheimer's disease is associated with biochemical and histopathological changes characterized by molecular abnormalities. Due to the lack of effective...  相似文献   
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