全文获取类型
收费全文 | 2557篇 |
免费 | 110篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 85篇 |
妇产科学 | 26篇 |
基础医学 | 276篇 |
口腔科学 | 34篇 |
临床医学 | 319篇 |
内科学 | 542篇 |
皮肤病学 | 26篇 |
神经病学 | 144篇 |
特种医学 | 25篇 |
外科学 | 181篇 |
综合类 | 49篇 |
一般理论 | 2篇 |
预防医学 | 338篇 |
眼科学 | 56篇 |
药学 | 348篇 |
3篇 | |
中国医学 | 50篇 |
肿瘤学 | 152篇 |
出版年
2024年 | 33篇 |
2023年 | 68篇 |
2022年 | 232篇 |
2021年 | 273篇 |
2020年 | 139篇 |
2019年 | 125篇 |
2018年 | 116篇 |
2017年 | 85篇 |
2016年 | 91篇 |
2015年 | 70篇 |
2014年 | 108篇 |
2013年 | 156篇 |
2012年 | 177篇 |
2011年 | 186篇 |
2010年 | 84篇 |
2009年 | 55篇 |
2008年 | 90篇 |
2007年 | 73篇 |
2006年 | 68篇 |
2005年 | 55篇 |
2004年 | 66篇 |
2003年 | 61篇 |
2002年 | 59篇 |
2001年 | 20篇 |
2000年 | 13篇 |
1999年 | 17篇 |
1998年 | 14篇 |
1997年 | 33篇 |
1996年 | 10篇 |
1995年 | 7篇 |
1994年 | 10篇 |
1993年 | 12篇 |
1992年 | 7篇 |
1991年 | 7篇 |
1990年 | 8篇 |
1989年 | 2篇 |
1988年 | 11篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 7篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1970年 | 1篇 |
1945年 | 1篇 |
1929年 | 1篇 |
1923年 | 1篇 |
排序方式: 共有2678条查询结果,搜索用时 15 毫秒
61.
Bayarchimeg Altankhishig Mohammad Ali Akbor Polan Youjing Qiu Md Riasat Hasan Takashi Saito 《Materials》2021,14(4)
The purpose of the present study was to investigate the effect of a peptide (i.e., SESDNNSSSRGDASYNSDES) derived from dentin phosphophoryn (DPP) with arginine-glycine-aspartic acid (RGD) motifs on odontoblast differentiation in vitro and to compare it with calcium hydroxide—a material used conventionally for vital pulp therapy—in terms of reparative dentin formation and pulp inflammation in vivo. Alkaline phosphatase activity assay and alizarin red S staining were performed to evaluate odontoblast-differentiation in cell culturing experiments. To observe the reparative dentin formation and pulp inflammation animal experiment was performed and examined by histological methods. The difference between the experimental group and the control group was analyzed statistically using a one-way ANOVA test. The results revealed that the DPP-derived RGD-containing peptide triggered odontoblast differentiation and mineralization in vitro. In rats undergoing direct pulp capping, the DPP-derived RGD-containing peptide was found to induce intensively formed reparative dentin with high compactness at week 4. On histological and morphometrical examinations, a smaller degree of pulpitis was observed in the specimens treated with the peptide than in those treated with calcium hydroxide. This study suggests that the DPP-derived RGD-containing peptide is a biocompatible, biodegradable and bioactive material for dentin regeneration. 相似文献
62.
Md Zohorul Islam Jesper Larsen Robert Skov Øystein Angen 《Diagnostic microbiology and infectious disease》2019,93(1):5-8
Optimal transportation of bacteria is important for accurate clinical interpretation, quantitative assays, and microbiome studies. A transport medium should ideally keep the bacteria alive without supporting growth or altering the relative proportions of the constituent species. We investigated the effect of nasal mucus and mucin on the growth and survival of two Staphylococcus aureus strains in liquid Amies transport medium at room temperature and 4?°C for 14?days. The study showed that the presence of nasal mucus in microbiological samples stimulated undesired S. aureus growth at room temperature in a dose-dependent manner. These findings underscore that microbiological samples from humans and animals should be stored at 4?°C until analysis to avoid undesired S. aureus growth. 相似文献
63.
Nadira Naznin Rakhi A.S.M. Rubayet Ul Alam Munawar Sultana Md. Mizanur Rahaman M. Anwar Hossain 《Journal of infection and chemotherapy》2019,25(6):444-451
Global emergence and dissemination of carbapenemases are clinically threatening, notably in countries with endemic blaNDM. To analyze the extent of carbapenemases in Bangladesh, 71 isolates were collected from 7 different clinical sources: wound swab (n = 38), pus (n = 13), urine (n = 9), blood (n = 4), tracheal aspirate (n = 3), pleural fluid (n = 1) and vaginal swab (n = 3) from Dhaka Medical College Hospital, Bangladesh. Among the isolates, 25 were resistant to at least one of the three carbapenems (imipenem, meropenem and doripenem), including 15 being resistant to all. These resistant isolates were identified as Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, P. hibiscicola, Proteus mirabilis, Providencia stuartii and Citrobacter sedlakii. Carbapenemase detection among these 25 isolates varied in individual phenotypic assays (83% in Modified Hodge Test, 50% in Combined Disk Test for Metallo-β-lactamase prediction) as compared with the genotypes observed (96% prevalence of various carbapenemases including blaOXA-1,48, blaNDM-1,5, blaVIM-2,5). blaOXA-48 was the most prevalent gene (84%) followed by blaNDM (72%). Coexistence of multiple gene combination such as blaNDM+blaOXA-48+blaOXA-1 was prevalent (48%). Harborage of blaVIM-5 (n = 1) was characterized for the first time, while blaNDM-5 (n = 5) was reported contemporarily with a recent study in Bangladesh. Presence of plasmids (64%) and integron class 1 (100%) signifies the transferable potential of resistant traits. The emergence of such new variants along with the presence of the mobile genetic elements demands strict surveillance and combating strategies. 相似文献
64.
Yusof Khairunnisa’ Md Makpol Suzana Fen Lye Siew Jamal Rahman Wan Ngah Wan Zurinah 《Journal of natural medicines》2019,73(4):745-760
Journal of Natural Medicines - Our previous study reported that combined treatment of γ-tocotrienol with 6-gingerol showed promising anticancer effects by synergistically inhibiting... 相似文献
65.
An efficient and cost-effective method was developed for the synthesis of two kinds of fused 4H-pyran derivatives, namely, dihydropyrano[2,3-c]pyrazole 4 and pyrano[3,2-c]chromenone 6. The reactions of 3-methyl-1-phenyl-5-pyrazolone/4-hydroxycoumarin with aromatic aldehydes and (E)-N-methyl-1-(methylthio)-2-nitroethenamine (NMSM), involving the Knoevenagel, Michael-addition, O-cyclization and elimination reactions under thermal heating, afforded the desired products. The synthesized compounds were characterized by standard spectroscopic techniques. Further, the structures of pyrazole-fused 4H-pyran 4a and coumarin-fused 4H-pyran 6b were confirmed by single-crystal XRD analysis. The short reaction time, good-to-excellent yields, elimination of the use of expensive, metallic and toxic catalysts or hazardous organic solvents and high atom-economy are some noteworthy features of this protocol.A practical and greener method for the synthesis of highly functionalized pyrazole and coumarin fused 4H-pyran derivatives by exploring NMSM under neat conditions at 110 °C is described. 相似文献
66.
Anwer Md. Khalid Mohammad Muqtader Iqbal Muzaffar Ansari Mohd Nazam Ezzeldin Essam Fatima Farhat Alshahrani Saad M. Aldawsari Mohammed F. Alalaiwe Ahmed Alzahrani Aiman A. Aldayel Abdullah M. 《Journal of thrombosis and thrombolysis》2020,49(3):404-412
Journal of Thrombosis and Thrombolysis - The purpose of the currents study was to enhance bioavailability of rivaroxaban (RXB) and reduce the food effect. RXB loaded PLGA nanoparticles... 相似文献
67.
Tanvir K. Chowdhury Md Zonaid Chowdhury Fahmida Mili John M. Hutson Tahmina Banu 《Pediatric surgery international》2014,30(5):527-532
Objective
In developing countries like Bangladesh, delayed presentation for disorders of sex development (DSD) is common, and provides some special problems for management. There remains significant controversy about appropriate sex assignment in this group. We aimed, therefore, to assess gender identity (GI) in 50 consecutive patients with DSD presenting to a referral centre in Chittagong, Bangladesh, and correlate it with Prader score, to see if the latter could be used to predict GI.Methods
A cross-sectional, case–control study of 50 consecutive children with DSD and 50 children with vascular anomalies was conducted in the Pediatric Surgical Clinic, Chittagong Medical College and Hospital. After informed consent, patients and controls provided oral answers to a GI questionnaire and had a detailed history and physical examination. Sex-typed activities were assessed by observations of a structured toy play and the child’s selection of a toy to keep. Both patients and parents then completed the Child Game Participation Questionnaire.Results
There were no differences in age (2–16 years, mean 8.74) between controls and DSD patients (11 46, XX DSD, 32 46, XY DSD, 4 MGD, 3 ovo-testicular DSD). Fifteen of the DSD patients (30 %) came from consanguineous marriages and only 2 of the control patients had consanguinity of their parents. For the 13-question GI interview, there was no overall difference between DSD cases and controls. For the 46, XX DSD subgroup, there was a significantly higher score (11.1 ± 7.1) compared with control girls (4.5 ± 4.7) (p < 0.05), while for DSD and control boys, there was a positive correlation with age and GI (p < 0.01). Prader score correlated with GI score in both control (r = 0.91) and DSD patients (r = 0.75) (p < 0.01), DSD girls played significantly less with girls’ toys than controls (p < 0.01), but there was no differences for the boys. Composite scores on GI and gender-related behaviour correlated with Prader score for DSD patients (r = 0.61) (p < 0.01).Conclusion
This study supports the view that GI and gender-role behaviour should be assessed routinely in DSD patients presenting after the neonatal period, so that sex assignment is in accordance with behaviour. Prader scores showed a good correlation with GI and gender role behaviour. 相似文献68.
69.
F. Cornélis Md Phd L. Hardwick PhD R. M. Flipo MD M. Martinez PhD S. Lasbleiz MB J. F. Prud' Homme MD T. H. Tran S. Walsh A. Delaye A. Nicod M. N. Loste V. Lepage MD K. Gibson K. Pile Md S. Djoulah PhD P. M. Danzé MD F. Lioté Md Phd D. Charron Md Phd J. Weissenbach PhD D. Kuntz MD T. Bardin MD B. P. Wordsworth Mb Frcp 《Arthritis \u0026amp; Rheumatology》1997,40(8):1387-1390
Objective. To investigate allelic variations of T cell receptor residues for a contribution to rheumatoid arthritis (RA) susceptibility. Methods. We conducted an RA case-control study involving 1,579 northwest Europeans: 766 patients with erosive and rheumatoid factor-positive disease and 813 control subjects. Productive changes of segments TCRAV6S1, TCRAV7S1, TCRAV8S1, TCRAV10S2, and TCRBV6S1, TCRBV6S7 were investigated by single-strand conformation polymorphisms. The TCRAV8S1 association was confirmed by restriction fragment length polymorphism. Results. In the systematic study (77 patients and 119 controls), an increase in 1 TCRAV8S1 genotype was found in the RA patients (P = 0.0004). This finding was replicated in 2 further populations, one from France (212 patients and 254 controls) and the other from Britain (477 patients and 440 controls), with a similar odds ratio (OR), which allowed pooling of the data and confirmation of the association (OR 1.3 [95% confidence interval 1.1-1.7], P = 0.008). Conclusion. These findings show evidence that TCRA is an RA susceptibility locus. 相似文献
70.
Haiko Sprott MD Andreas Müller PhD Hartmut Heine Md Phd 《Arthritis \u0026amp; Rheumatology》1997,40(8):1450-1454
Objective. To determine if abnormal collagen metabolism is a characteristic of fibromyalgia. Methods. The diagnosis of fibromyalgia was made according to the American College of Rheumatology criteria. Skin biopsy samples were obtained from the trapezius region of 8 patients with fibromyalgia. Urine was collected under standardized conditions from 55 control subjects and 39 patients with fibromyalgia, and serum was obtained from 17 controls and 22 patients with fibromyalgia. Pyridinoline (Pyd), an indicator of connective tissue disease, and deoxypyridinoline (Dpyd), an indicator of bone degradation, both of which represent products of lysyl oxidase-mediated crosslinking in collagen, were analyzed by ion-paired and gradient high-performance liquid chromatography (HPLC) methods with fluorescence detection. Levels of hydroxyproline (Hyp), a collagen turnover marker, were also measured. The findings were related to creatinine levels, and the Pyd:Dpyd ratio was determined. Results. Highly ordered cuffs of collagen were observed around the terminal nerve fibers by electron microscopic examination of biopsy tissue from all 8 patients with fibromyalgia, but were not observed in any of the control skin samples. The Pyd:Dpyd ratios in the urine and serum and the Hyp levels in the urine were significantly lower in patients with fibromyalgia than in healthy controls. Conclusion. Decreased levels of collagen cross-linking in fibromyalgia may contribute to remodeling of the extracellular matrix and collagen deposition around the nerve fibers, and may contribute to the lower pain threshold at the tender points. Analysis of altered collagen metabolism either by histologic examination on biopsy, or preferably, by HPLC analysis of collagen metabolites in urine or serum may aid in understanding more about the pathogenesis of fibromyalgia. 相似文献