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81.
82.
Background
Previous studies have shown a significant increase in tear protein peaks in the tears of diabetic patients suffering from dry eye. The aim of this study was to analyze the tear protein patterns from patients with diabetes mellitus who do not suffer from ocular surface diseases (DIA).Methods
A total of 515 patients were examined in this study (255 healthy subjects (controls) and 260 patients suffering from diabetes mellitus). Tear proteins were separated by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis. After digital image analysis densitometric data files were created and subsequently used for multivariate statistical procedures.Results
A significant increase in the number of peaks was detected in diabetic patients compared to controls (P < 0.0003). The analysis of discriminance revealed a highly significant discrimination between diabetic patients and controls (Wilks lambda: 0.27; P < 0.000001). Furthermore, a significant difference in the protein pattern of diabetic patients could be detected between those suffering from dry eye or not (P < 0.002). The changes in protein patterns of diabetic patients increased with the duration of the diabetic disease. In diabetic patients with a disease duration longer than 10 years the changes were significantly more expressed than in patients with a shorter diabetic history (P < 0.003) and in healthy subjects (P < 0.0001).Conclusions
The tear protein patterns of diabetic patients are very different in the number and intensity of spots from those of healthy subjects. Furthermore, it could be demonstrated that the differences found in the tear patterns of diabetic patients are not equal to those found in previous studies in patients suffering from dry-eye disease. The alterations in the diabetic tears were correlated with the duration of the diabetic disease. With longer disease, history changes in the tear protein patterns increased. With the course of the disease some protein peaks appeared that are not present in healthy persons. Our study shows that the analysis of electrophoretic tear protein patterns is a new non-invasive approach in the early diagnosis and analysis of the pathogenesis of diabetes induced ocular surface disease. 相似文献83.
Alagarsamy V Salomon VR Vanikavitha G Paluchamy V Chandran MR Sujin AA Thangathiruppathy A Amuthalakshmi S Revathi R 《Biological & pharmaceutical bulletin》2002,25(11):1432-1435
A series of novel 2-phenyl-3-substituted quinazolin-4(3H)-ones have been synthesized by treating methyl-N-(2-phenyl quinazolin-3-yl-4(3H)-one) dithiocarbamate with different amines, the starting material dithiocarbamate was synthesized from anthranilic acid. The title compounds were investigated for analgesic, anti-inflammatory and antibacterial activities. All the test compounds exhibited significant activity, the compounds A1, A2 and A3 shown more potent analgesic activity, and the compound A3 shown more potent anti-inflammatory activity than the reference standard diclofenac sodium. 相似文献
84.
Bioassay-guided fractionation of a root bark extract of Symphonia globulifera has yielded, in addition to stigmasterol, two new xanthones with isoprenoid units, named globulixanthones A (1) and B (2). The structures of these compounds have been elucidated by spectroscopic means. They possess significant cytotoxicity in vitro against the KB cell line. 相似文献
85.
Le Pont F Pech N Boelle PY Giraud M Gilloire A Halfen S de Colomby P;ACSAG Investigators 《Sexually transmitted diseases》2003,30(1):6-9
BACKGROUND: Quantitative assessment of multiple sexual partnerships and concurrency may help to elucidate the large observed differences in the prevalence of AIDS among population subgroups and countries. GOAL: The goals of the study were (1) to develop a global scale of dynamic patterns of sexual partnerships, including concurrency with new partners and stable concurrency; (2) to apply this scale to three Caribbean regions characterized by different cumulative rates of incidence of AIDS; and (3) to compare the concurrency rates given by this scale with those of other published methods. STUDY DESIGN: We defined an individual scale based on 6 patterns of sexual behavior over the previous 12-month period, by using a simple algorithm to combine 7 variables. We then applied this scale to cross-sectional data collected from men living in three French Caribbean regions: Guadeloupe, Martinique, and Guyana. RESULTS: We found that all adults of all age classes in the three regions studied frequently had multiple (>2) and concurrent partnerships. The patterns of sexual behavior in the three regions were consistent with the respective cumulative incidence rates of AIDS, and a lower rate of concurrency with new partners and a higher rate of stable partnership concurrency were noted in Martinique, especially among 45- to 59-year-olds. The rate of concurrent partnerships was found to depend on the criteria used to define them and on the observation period (a given moment, or a defined period). Our definition gave a higher rate of concurrency than previously published indicators. CONCLUSION: The proposed scale can be applied to easy-to-collect data in cross-sectional population surveys and takes into account a wide variety of behaviors, including different types of concurrency. 相似文献
86.
Rios LY Bennett RN Lazarus SA Rémésy C Scalbert A Williamson G 《The American journal of clinical nutrition》2002,76(5):1106-1110
BACKGROUND: Polyphenolic procyanidins are abundant flavonoid polymers in Western diets. In vitro biological activity has been reported for these compounds, but activity in vivo depends on the amount and chemical nature of the flavonoids reaching the gastrointestinal tract. Degradation of procyanidins under simulated gastric conditions at pH 2.0 has been reported in vitro. OBJECTIVE: The objective was to examine whether depolymerization of procyanidins occurs in the stomach of human subjects in vivo. DESIGN: After an overnight fast, 6 healthy subjects (3 men and 3 women) consumed 500 mL of a cocoa beverage containing 733 mg procyanidin polymers and 351 mg structurally related flavanol monomers. With the use of a nasogastric tube, stomach contents were collected every 10 min after beverage ingestion until the stomach was emptied. Flavanols and procyanidins (up to pentamers) were quantified by normal and reversed-phase HPLC. RESULTS: In all subjects, gastric transit lasted approximately 50-60 min. No change in the HPLC profile of procyanidins was observed during this period, showing that procyanidins were remarkably stable in the stomach environment. CONCLUSION: The results suggest that most ingested procyanidins reach the small intestine intact and are available for absorption or metabolism. 相似文献
87.
88.
Diffusion-weighted imaging of patients with subacute cerebral ischemia: comparison with conventional and contrast-enhanced MR imaging 总被引:12,自引:0,他引:12
Augustin M Bammer R Simbrunner J Stollberger R Hartung HP Fazekas F 《AJNR. American journal of neuroradiology》2000,21(9):1596-1602
BACKGROUND AND PURPOSE: The importance of diffusion-weighted imaging (DWI) for delineating acute ischemic lesions has been investigated extensively; however, few studies have investigated the role of DWI in the subacute stage of stroke. Because these lesions tend to appear bright throughout the first days of ischemia, owing to restricted diffusion, we speculated that DWI could also improve the detection of subacute infarcts as compared with conventional and contrast-enhanced MR imaging. METHODS: Interleaved echo-planar DWI with phase navigation was performed on a 1.5-T MR unit in a consecutive series of 53 patients (mean age, 66 +/- 14 years) with suspected recent cerebral ischemia. The interval between onset of clinical symptoms and MR imaging ranged from 1 to 14 days (mean, 6 +/- 4 days). Contrast material was given to 28 patients in a dose of 0.1 mmol/kg. RESULTS: DWI clearly delineated recent ischemic damage in 39 patients (74%) as compared with 33 (62%) in whom lesions were identified or suspected on conventional T2-weighted images. DWI provided information not accessible with T2-weighted imaging in 17 patients when evidence of lesion multiplicity or detection of clinically unrelated recent lesions was included for comparison. Subacute ischemic lesions were also seen more frequently on DWI sequences than on contrast-enhanced images (20 versus 13 patients). DWI was more likely to make a diagnostic contribution in the first week of stroke and in patients with small lesions or preexisting ischemic cerebral damage than was conventional MR imaging. CONCLUSION: Recent ischemic damage is better shown on DWI sequences than on conventional and contrast-enhanced MR images throughout the first days after stroke and may provide further information about the origin of clinical symptoms. Adding DWI to imaging protocols for patients with subacute cerebral ischemia is recommended. 相似文献
89.
90.
We saw three patients working in the production of polyurethanes, who showed mydriasis and cycloplegia of unknown origin. In one patient there was also a transient opacification of corneal stroma. After discontinuation of working both mydriasis and cycloplegia resolved completely within 3-5 days. Because of the history and the analysis of chemical reactions involved in the production of polyurethanes there is strong evidence that both mydriasis and cycloplegia have been caused by topical and (/or) systemic intoxication with the aryl diet of the isocyanate molecule. 相似文献