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排序方式: 共有910条查询结果,搜索用时 15 毫秒
171.
Ahmed Jamleh Mohannad Nassar Abdulmohsen Alfadley Azhar Alanazi Hadeel Alotiabi Maryam Alghilan Khalid Alfouzan 《Materials》2022,15(9)
This study assesses the retreatability of TotalFill bioceramic (TFBC) and AH Plus (AHP) sealers and their impact on retreatment force and torque. Twenty-six premolar teeth with single oval canals were instrumented, obturated using the matched gutta-percha cone technique with one of the tested sealers, and then temporized. After a 6-month incubation at 37 °C and 100% humidity, the canals were retreated with the XP Shaper system. During retreatment, the generated force and torque were measured. Micro-CT scanning was run before and after the retreatment procedure to analyze the remaining obturating materials in the canals. The apically directed maximum force in AHP was higher than that in TFBC. The coronally directed maximum force and the maximum torque were comparable between the groups. A higher amount of remaining obturating materials was found in the AHP compared to that in the TFBC. Based on these findings, endodontic sealer had an influence on retreatability, and the TFBC showed less remaining obturating materials and lower retreatment forces in the apical direction compared to the AHP in extracted teeth with oval canals. 相似文献
172.
Farooq Ahmed Najma Iqbal Malik Nudra Malik Madeeha Gohar Qureshi Muhammad Shahzad Muhammad Shahid Sidra Zia Kun Tang 《Nutrients》2022,14(13)
Severe Acute Malnutrition (SAM) is a serious public health problem in many low- and middle-income countries (LMICs). Therapeutic programs are often considered the most effective solution to this problem. However, multiple social and structural factors challenge the social inclusion, sustainability, and effectiveness of such programs. In this article, we aim to explore how poor and remote households face structural inequities and social exclusion in accessing nutrition-specific programs in Pakistan. The study specifically highlights significant reasons for the low coverage of the Community Management of Acute Malnutrition (CMAM) program in one of the most marginalized districts of south Punjab. Qualitative data are collected using in-depth interviews and FGDs with mothers and health and nutrition officials. The study reveals that mothers’ access to the program is restricted by multiple structural, logistical, social, and behavioral causes. At the district level, certain populations are served, while illiterate, and poor mothers with lower cultural capital from rural and remote areas are neglected. The lack of funding for nutrition causes the deprioritization of nutrition by the health bureaucracy. The subsequent work burden on Lady Health Workers (LHWs) and the lack of proper training of field staff impact the screening of SAM cases. Moreover, medical corruption in the distribution of therapeutic food, long distances, traveling or staying difficulties, the lack of social capital, and the stigmatization of mothers are other prominent difficulties. The study concludes that nutrition governance in Pakistan must address these critical challenges so that optimal therapeutic coverage can be achieved. 相似文献
173.
Mansoor Ahmed Khan Nurain Baig Moghul Maisra Azhar Butt Mubin Mustafa Kiyani Ibraheem Zafar Ali Imran Bukhari 《Journal of basic microbiology》2021,61(7):603-611
Curcumin nanoparticles were most recently considered in medical research because of their antibacterial properties. The main objective of the study was to develop the green synthesis and antibacterial activity of curcumin nanoparticles using Curcuma longa. The processing of curcumin nanoparticles was carried out after the collection, identification, and extraction of curcumin. The effect of a sample on the synthesis of nanoparticles, such as curcumin aqueous concentrations (5, 10, and 20 mg/ml) and curcumin nanoparticles (5, 10, and 20 mg/ml), and the antibacterial effect of these nanoparticles on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and the fungal strain Aspergillus niger. For examining antibacterial and anti-fungal activity disc diffusion method was performed, followed by the zone of inhibition. According to X-ray diffraction and scanning electron microscope analysis, nanoparticles have spherical shapes and size of 42.64 nm. Results showed that a high dose of 20 mg/ml curcumin nanoparticles have more antibacterial activity than curcumin extracts in E. coli as it showed the largest diameter of zone of inhibition as compared to other doses. Other bacterial and fungal strains also showed significant results but E. coli was most prominent. The biosynthesis of curcumin nanoparticles using an aqueous extract of C. longa is a clean, inexpensive, and safe method that has not been used any toxic substance and consequently does not have side effects. Since several pathogenic species have acquired antibiotic resistance, the combination of curcumin with various nanoparticles would be beneficial in the cure of pathogenic diseases. 相似文献
174.
175.
Ahmed Alnajar MD Elizabeth F. Aleong Muhammad Z. Azhar Ryan Azarrafiy MD MPH Joseph Lamelas MD 《Journal of cardiac surgery》2020,35(12):3539-3544
Aortic arch and hemiarch surgery necessitate the temporary interruption of blood perfusion to the brain. Despite its complexity, hemiarch and ascending aortic surgery can be performed via a minimally invasive approach. Due to the higher risk of neurological injury during a circulatory arrest, several techniques were developed to further protect the brain during this surgery. We searched the Embase, Medline, and Cochrane databases and identified articles reporting outcomes of antegrade and retrograde cerebral perfusion strategies. Herein, we outline surgical approaches, intra-operative technical considerations, and clinical outcomes of hemiarch and ascending aortic surgery. Hemiarch and ascending aortic surgery is associated with a higher risk of mortality and morbidity. Attention to the optimal approach and cerebral protection strategy has been shown to significantly affect outcomes and mitigate risk. 相似文献
176.
Ashesh B Jani Michael J Blend Russell Hamilton Charles Brendler Charles Pelizzari Lani Krauz Srinivasan Vijayakumar Bipin Sapra Azhar Awan Ralph R Weichselbaum 《Journal of nuclear medicine》2004,45(4):571-578
The aim of this study was to evaluate the role of radioimmunoscintigraphy (RIS) directed against prostate-specific membrane antigen (PSMA) in influencing postradical retropubic prostatectomy (RRP) radiotherapy (RT) decision making. METHODS: The records of consecutive patients who underwent RRP, who were referred for consideration of RT, and for whom an RIS scan was obtained were reviewed. The RT decisions, with regard to (a) the decision to offer RT and (b) the general volume to be treated [prostate fossa (PF) only versus PF + pelvis (P)] before knowledge of the RIS findings were charted. The RIS findings, with regard to uptake in the PF, uptake in the P, or extrapelvic (EP) uptake were tabulated. Then, the RT treatment decisions based on the RIS knowledge were evaluated and compared with the pre-RIS RT treatment decisions. RESULTS: Of the 54 patients originally referred for post-RRP RT, the initial decision was to recommend RT to the PF only in 52 cases and to PF+P in 2 cases. The RIS findings were as follows: PF only, 43 patients; PF+P, 8 patients; PF+EP, 2 patients; PF+P+EP, 1 patient. After knowledge of these RIS results, the decision to offer RT was withdrawn in 4 of 54 patients (7.4%; P = 0.046). Furthermore, RIS changed the general treatment volume (PF only to PF+P) in 6 of 54 patients (11.1%; P = 0.015). In total, RIS altered the RT decision in 10 of 54 patients (18.5%; P = 0.0067). Three-year biochemical failure-free survival (with failure defined as 2 consecutive prostate-specific antigen [PSA] rises above 0.2 ng/mL after PSA nadir) was 78%; no patient, disease, or treatment factor reached statistical significance on univariate or multivariate analysis. CONCLUSION: RIS was found to influence post-RRP RT decision making for the identification of patients not likely to benefit from RT and for guiding general target volume definition. 相似文献
177.
Effects of antimicrotubule agents on phospholipid metabolism in rat hepatic subcellular membranes 总被引:1,自引:0,他引:1
Treatment of animals with antimicrotubule drugs has been shown to cause a perplexing variety of cellular changes which, theoretically, could be the result of changes in endomembrane biosynthesis, composition or flow. In the current study we have focused on this possibility by identifying antimicrotubule drug-induced changes in the phospholipid metabolism of hepatic subcellular membranes. Young adult rats were pretreated with radiolabeled [32 P]orthophosphate for 12 hr, and subsequently given saline, colchicine (2.5 mg/kg body wt) or vinblastine (20 mg/kg body wt) for 4 additional hr. Afterwards, the livers were homogenized, and separate microsomal and Golgi membrane fractions were prepared and subjected to phospholipid extraction and identification using two-dimensional thin-layer chromatography. The results show that colchicine and vinblastine given in vivo caused specific, rapid and in some cases, dramatic changes in phospholipid turnover in different membrane fractions of rat liver. The drugs specifically increased labeling of phosphatidylinositol-4-monophosphate and phosphatidylinositol-4,5-biphosphate and decreased the radioactivity associated with phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol in all fractions examined. In contrast, the antimicrotubule drugs produced a differential effect on the labeling pattern of sphingomyelin and lysophosphatidylcholine, i.e. they stimulated labeling of these phospholipids in microsomes, produced no changes in heavy Golgi fractions, and markedly increased their labeling in light Golgi fractions. These data suggest that antimicrotubule drugs restrict the incorporation of certain precursor phospholipids into forming membranes but do not affect the subsequent metabolism of these phospholipids. At the same time, the drugs appear to retard the flow of membranes from one cellular compartment to another. 相似文献
178.
The level of fructose 2,6-bisphosphate (F2,6P2), a potent stimulator of 6-phosphofructo-1-kinase and inhibitor of fructose 1,6-bisphosphatase, was measured in three different muscle types (tensor fascia latae, biceps femoris, and soleus) and in the liver of normal and diabetic rats. The mean (+/- SEM) content of F2,6P2 (nanomoles per g tissue) varied among the three types of skeletal muscle in normal rats, with the biceps femoris having the highest (0.97 +/- 0.15) and the soleus the lowest (0.57 +/- 0.03) levels. However, these differences were unrelated to simultaneous estimates of skeletal muscle activity of 6-phosphofructo-1-kinase activity. The total concentration of F2,6P2 was more than 8-fold higher (8.5 +/- 0.9) in the liver, and this value fell to 5.3 +/- 0.8 (P less than 0.05) after the induction of diabetes with streptozotocin. In contrast, F2,6P2 levels did not fall in skeletal muscle of rats with streptozotocin-induced diabetes, and the concentration actually increased. Thus, the fall in hepatic F2,6P2 concentration associated with insulin deficiency was not observed in skeletal muscle. 相似文献
179.
Pronounced differences are found between characteristics of networks developed in plasma and those developed in pure fibrinogen solution. Networks in plasma have thicker fibres, are more permeable and have lower tensile strength. In this investigation the role of some plasma proteins as determinants of network structure under physiological conditions of clotting has been examined in an attempt to account for the differences in network structure in plasma and fibrinogen solution. The effect of physiological concentrations of antithrombin III, fibronectin, albumin, alpha globulin and gamma globulin on fibrin network structure was examined using mass-length ratio (muT) from turbidity, bulk network permeability (tau) and kinetics of network development. It was found that differences in fibrin network structure developed in plasma and pure fibrinogen solution could not be accounted for by alterations induced in network properties by albumin, gamma globulin, alpha globulin, fibronectin and antithrombin III. It is concluded that the final network structure is determined by the kinetics of fibrin fibre growth and is highly responsive to the presence of plasma proteins. 相似文献
180.