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31.
32.
The development of new orally dispersible tablets containing amlodipine (AML) inclusion complexes in hydroxypropyl-β-cyclodextrin (HP-β-CD) and in methyl-β-cyclodextrin (Me-β-CD) was studied. The methods of obtaining amlodipine and the physical and chemical properties of the inclusion complexes using the two cyclodextrins was investigated separately. Solid inclusion complexes were obtained by three methods: kneading, coprecipitation, and lyophilization, at a molar ratio of 1:1. For comparison, a physical mixture in the same molar ratio was prepared. The aim of the complexation process was to improve the drug solubility. As the lyophilization method leads to a complete inclusion of the drug in the guest molecule cavity, for both used cyclodextrins, these types of compounds were selected as active ingredients for the design of orally dispersible tablets. Subsequently, the formulation of the orodispersible tablets containing AML-HP-β-CD and AML-Me-β-CD inclusion complexes and quality parameters of the final formulation were evaluated. The results prove that F1 and F4 formulations, based on silicified microcrystalline cellulose, which contains insignificant proportions of very small or very large particles, had the lowest moisture degree (3.52% for F1 and 4.03% for F4). All of these demonstrate their porous structure, which led to good flowability and compressibility performances. F1 and F4 formulations were found to be better to manufacture orally dispersible tablets.  相似文献   
33.

Ethnopharmacological relevance

Aerial parts of Heracleum sphondylium L. (HS) are used in traditional medicine to treat hypertension. To provide pharmacological basis for this use, we investigated the vasorelaxant effects of a dichloromethane extract of HS (HSDE) and the mechanisms involved.

Materials and methods

Activity of HSDE was evaluated on rat isolated thoracic aortic rings.

Results

HSDE induced vasorelaxation in phenylephrine (PE, 10−6 mol/L) and high KCl—(6×10−2 mol/L) pre-contracted aortic rings that was independent on the presence of endothelium. HSDE markedly decreased extracellular Ca2+-induced contraction in high-KCl and PE pre-challenged rings. It also inhibited the intracellular Ca2+ release sensitive to PE (10−6 M). The relaxant effect of HSDE were blunted by 4-amino-pyridine (4-AP, 10−3 mol/L), an inhibitor of voltage-dependent K+ channels.

Conclusion

Our results provide the first evidence that a dichloromethane extract of Heracleum sphondylium L. exhibits vasorelaxant properties through endothelium-independent mechanisms involving the inhibition of Ca2+ mobilization and changes in Kv channel conductances. These data argue for its use as antihypertensive therapy in traditional medicine.  相似文献   
34.
INTRODUCTION: Psychological factors are believed to play an important role in infertility and its treatment Psychological problems may be considered to be risk factors and the cause of reduced infertility, as well as contribute to an unsuccessful outcome of infertility treatment. OBJECTIVES: The aim of the study was to investigate the correlation between semen parameters and quality of life in male patients with fertility problems. MATERIAL AND METHODS: 70 patients with infertility treated in Andrology Clinic were divided into two groups according to semen parameters: bad and good quality of semen. The quality of life has been with the help of Campbell questionnaires. RESULTS: Significantly lower questionnaire score in bad quality of semen group has been observed, in comparison with normozoospermic men. High correlation between concentration, motility and morphology in comparison with the quality of life has been observed in the studied group of patients. CONCLUSION: The quality of life is directly associated with semen parameters such as concentration, motility and morphology of sperm.  相似文献   
35.
OBJECTIVE: There is an increasing evidence that genetic factors play a role in the etiology of malignant tumors. Mutations of BRCA1 and BRCA2 genes are responsible for an increased risk of ovarian cancer. The role of mutations in NOD2 gene in this type of neoplasm is still under investigation. THE AIM: The aim of this study was to determine: 1. incidence of NOD 2 3020insC constitutional mutation in a group of consecutive women with ovarian cancer, 2. risk of developing ovarian cancer in patients with NOD2 gene mutation, 3. clinical and pathological features of ovarian cancer in NOD2 gene mutation carriers. PATIENTS AND METHODS: Clinical and pathological data were collected from 257 non-selected patients with primary epithelial ovarian cancer. The researches identified NOD2 3020insC gene mutation. On the basis of patient source documentation we obtained the data concerning the age of patients at diagnosis, histopathological recognition, FIGO stage and morphological grade G. RESULTS: 19 out of 257 women were identified with germ-line 3020insC mutation of NOD2 gene (7.39%). An increased risk of ovarian cancer in NOD2 mutation carriers was not revealed (OR=1.01; p=0.928; 95% Cl=0.61-1.66). The mean age at diagnosis of patients with NOD2 mutation was 54.8 (SD=9.9), while for non-carriers it was 53.2 (SD=10.2). The difference between these frequencies was statistically irrelevant (p=0.550). Clinical and pathological profile of ovarian cancer was made. We assessed the following features: age at disease onset, histopathology, FIGO stage and morphological grade G. For NOD2 mutation carriers no statistically significant features of ovarian cancer were revealed. CONCLUSION: 1. Despite high frequency of constitutional mutations occurrence in NOD2 gene in women with ovarian cancer, genetic testing seem not to be justified in all women diagnosed with this disease. 2. Due to a lack of increased risk of ovarian cancer in NOD2 gene mutation carriers, proceedings for them may not differ from recommendations for general population. 3. It is difficult to determine characteristic clinical and pathological features of ovarian cancer for NOD2 gene mutation carriers.  相似文献   
36.
OBJECTIVES: The aim of the study was to analyze the incidence of malignant cervical carcinomas found in the material from Histopathological Laboratory in Zawiercie District Hospital. MATERIAL AND METHODS: The examined materials included histopathological results concerning segments and scrapings from gynecological procedures and the results of the segments, collected during gynecological operations performed in the years 2000-2005, in which malignant neoplasms of uterine cervix had been diagnosed. The data concerning the neoplasms were analysed, taking into account the following parameters: the number of neoplasms found in relation to the total number of diagnostic procedures performed, patients' age, histological type of the neoplasm and the degree of clinical progression based on FIGO classification. RESULTS: In the examined material, there were 50 cases of cervical carcinomas, with the highest incidence in patients aged between 50-59. The most common morphological type was squamous carcinoma and the majority of cervical carcinomas was characterized by the I degrees of disease clinical progression--38 cases, also 4 preinvasive carcinomas were found and 8 cancers of the II degrees of progression, according to FIGO classification. CONCLUSION: A considerable decrease of cervical carcinomas incidence, observed in the study period and the number of neoplasms found in an early progression stage are the effect of conducted screening examinations, due to which precancerous conditions are diagnosed and treated.  相似文献   
37.
38.
Nonalcoholic fatty liver disease is now recognized as the most common cause of chronic liver disease with an increasing prevalence in both adults and children. Although the symptoms are absent or poorly expressed in most cases, some patients may progress to end-stage liver disease. The pathogenesis of NAFLD is known to be multifactorial. Current therapeutic recommendations focus on lifestyle changes in order to reduce the incidence of risk factors and drugs targeting major molecular pathways potentially involved in the development of this disease. Given that a pharmacological treatment, completely safe and effective, is not currently known in recent years more research has been done on the effects that some bio-active natural compounds, derived from plants, have in preventing the onset and progression of NAFLD. Numerous studies, in animals and humans, have shown that phytosterols (PSs) play an important role in this pathology. Phytosterols are natural products that are found naturally in plant. More than 250 phytosterols have been identified, but the most common in the diet are stigmasterol, β-sitosterol, and campesterol. Consumption of dietary PSs can reduce serum cholesterol levels. Due to these properties, most studies have focused on their action on lipid metabolism and the evolution of NAFLD. PSs may reduce steatosis, cytotoxicity oxidative stress, inflammation, and apoptosis. The purpose of this review is to provide an overview of the importance of dietary phytosterols, which are a window of opportunity in the therapeutic management of NAFLD.  相似文献   
39.
Fatty acid composition of serum lipids and adipose tissue triacylglycerols (AT-TAG) partly reflect dietary fatty acid intake. The fatty acid composition is, besides the diet, also influenced by desaturating enzymes that can be estimated using product-to-precursor fatty acid ratios. The interrelationships between desaturase indices derived from different serum lipid fractions and adipose tissue are unclear, as well as their associations with obesity and insulin resistance. We aimed to investigate cross-sectional correlations between desaturase indices as measured in serum lipid fractions (phospholipids; PL and free fatty acids; FFA) and in adipose tissue (AT-TAG). In a population-based sample of 301 healthy 60-year-old men various desaturase indices were assessed: stearoyl-CoA-desaturase (16:1n-7/16:0; SCD-16 and 18:1n-9/18:0; SCD-18, respectively), delta-6-desaturase (20:3n-6/18:2n-6; D6D) and delta-5-desaturase (20:4n-6/20:3n-6; D5D). Correlations with BMI and insulin resistance (HOMA-IR) were also examined. SCD-16 and D5D were significantly correlated between fractions and tissues (all r > 0.30), whereas SCD-18 and D6D were not. Desaturase indices in serum FFA and AT-TAG were significantly correlated; SCD-16 (r = 0.63), SCD-18 (r = 0.37), and D5D (r = 0.43). In phospholipids, SCD-16 was positively correlated to BMI (r = 0.15), while D5D negatively to both BMI (r = -0.30) and HOMA-IR (r = -0.31), all p < 0.01. D6D in both phospholipids and AT-TAG was positively correlated to HOMA-IR and BMI (all p < 0.01). In conclusion, SCD-1 and D5D activity indices showed overall strong correlations between lipid pools. SCD-1 activity index in adipose tissue is best reflected by 16:1/16:0-ratio in serum FFA, but associations with obesity and insulin resistance differ between these pools. D5D in PL was inversely related to obesity and insulin resistance, whereas D6D index showed positive associations.  相似文献   
40.
Relatively easy treatment of glass aggregates can lead to the formation of a highly porous zeolite aggregate. This study focuses on the possibility of using such an aggregate as an active additive to a gypsum binder. The physical properties of hardened gypsum composites with zeolite fillers doped with various metal ions (Ni2+, Cu2+, and Zn2+) have been compared. In addition to studies of the basic physical properties of the composites, structural and microstructural studies as well as antimicrobial tests were performed. It was found that the parameters of the composites with the addition of various ions do not differ significantly from the reference but modifies the microstructure. Among other things, the ions analyzed reduce the microporosity of gypsum composites. Using all aggregates, a product with adequate strength (above 2 MPa) and thermal conductivity (about 0.35 W/m·K) appropriate for typical lightweight gypsum composites can be obtained. The bacteriostatic effect of formulations with copper and zinc against Escherichia coli and with copper against Staphylococcus aureus was found.  相似文献   
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