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排序方式: 共有897条查询结果,搜索用时 15 毫秒
41.
Kontoyiannis DP Lewis RE Lionakis MS Albert ND May GS Raad II 《Diagnostic microbiology and infectious disease》2003,47(2):415-419
We investigated the in vitro activity of sequential itraconazole and caspofungin against 10 isolates of Aspergillus fumigatus. Previous exposure of A. fumigatus to itraconazole resulted in dose-dependent enhanced effects of caspofungin and vice versa. Our finding suggests a preferential role for azole-caspofungin sequential combinations and merits further in vivo investigation. 相似文献
42.
Shenkar R Elliott JP Diener K Gault J Hu LJ Cohrs RJ Phang T Hunter L Breeze RE Awad IA 《Neurosurgery》2003,52(2):465-77; discussion 477-8
OBJECTIVE: We sought to identify genes with differential expression in cerebral cavernous malformations (CCMs), arteriovenous malformations (AVMs), and control superficial temporal arteries (STAs) and to confirm differential expression of genes previously implicated in the pathobiology of these lesions. METHODS: Total ribonucleic acid was isolated from four CCM, four AVM, and three STA surgical specimens and used to quantify lesion-specific messenger ribonucleic acid expression levels on human gene arrays. Data were analyzed with the use of two separate methodologies: gene discovery and confirmation analysis. RESULTS: The gene discovery method identified 42 genes that were significantly up-regulated and 36 genes that were significantly down-regulated in CCMs as compared with AVMs and STAs (P = 0.006). Similarly, 48 genes were significantly up-regulated and 59 genes were significantly down-regulated in AVMs as compared with CCMs and STAs (P = 0.006). The confirmation analysis showed significant differential expression (P < 0.05) in 11 of 15 genes (angiogenesis factors, receptors, and structural proteins) that previously had been reported to be expressed differentially in CCMs and AVMs in immunohistochemical analysis. CONCLUSION: We identify numerous genes that are differentially expressed in CCMs and AVMs and correlate expression with the immunohistochemistry of genes implicated in cerebrovascular malformations. In future efforts, we will aim to confirm candidate genes specifically related to the pathobiology of cerebrovascular malformations and determine their biological systems and mechanistic relevance. 相似文献
43.
Mutational analysis of 206 families with cavernous malformations 总被引:4,自引:0,他引:4
Laurans MS DiLuna ML Shin D Niazi F Voorhees JR Nelson-Williams C Johnson EW Siegel AM Steinberg GK Berg MJ Scott RM Tedeschi G Enevoldson TP Anson J Rouleau GA Ogilvy C Awad IA Lifton RP Gunel M 《Journal of neurosurgery》2003,99(1):38-43
OBJECT: A gene contributing to the autosomal-dominant cerebral cavernous malformation (CCM) phenotype, KRIT1 (an acronym for Krev Interaction Trapped 1), has been identified through linkage analysis and mutation screening. The authors collected blood samples from 68 patients with familial CCM and 138 patients with apparently sporadic CCM as well as from their families, in an effort to characterize the prevalence and spectrum of disease-causing sequence variants in the KRIT1 gene. METHODS: The authors used single-strand conformational polymorphism analysis to identify genomic variants in KRIT1, which were sequenced to determine the specific mutation. Among 43 Hispanic-American kindreds who immigrated to the southwestern US from northern Mexico, 31 share an identical founder mutation. This Q455X mutation is found in 18 (86%) of 21 persons with a positive family history and in 13 (59%) of 22 persons with apparently sporadic CCM. This mutation was not found among 13 persons with CCM who were recruited from Mexico. These findings establish the key role of a recent founder mutation in Hispanic persons with CCM who live in the US. Although nearly all Hispanic families in the US in which there are multiple CCM cases linked to the CCM1 locus, only 13 of 25 non-Hispanic CCM-carrying families have displayed evidence of linkage to the CCM1 locus. Among these 13 families, the authors identified eight independent mutations in nine kindreds. They identified four additional mutations among 22 familial CCM kindreds with no linkage information, bringing the total number of independent mutations to 12. Inherited KRIT1 mutations were not detected among 103 non-Hispanic persons in whom a family history of CCM was rigorously excluded. CONCLUSIONS: All mutations were nonsense mutations, frame-shift mutations predicting premature termination, or splice-site mutations located throughout the KRIT1 gene, suggesting that these are genetic loss-of-function mutations. These genetic findings, in conjunction with the clinical phenotype, are consistent with a two-hit model for the occurrence of CCM. 相似文献
44.
Al-Khatib I Ju'ba A Kamal N Hamed N Hmeidan N Massad S 《International journal of environmental health research》2003,13(4):315-326
Al-Ama'ri camp is situated to the south of Ramallah city in the West Bank of Palestine. It is densely populated, with a total population of 4046, divided into 760 households, on a surface area of 93 dunums (93000 m(2)). In this research, the relationship between the housing conditions at Ama'ri camp and the prevalence and incidence rates of upper respiratory tract diseases has been studied. The diseases and symptoms most encountered in winter, and those include: common cold, cough, pharyngitis, influenza, ear infection, asthma and bronchitis have been studied. It was found that these are diseases directly related to poor housing conditions. Cold housing, presence of dampness and moulds, dust and smoke, burning of biomass fuel, crowding, poor ventilation and inadequate lighting problems are commonly found in the houses of this refugee camp. 相似文献
45.
46.
Soumaya SG Aida M Sami M Khaled N Med Badis C Sami J Ezedine S Zohra M Issam L Faouzia Z Hedi R Hela C Naima K 《La Tunisie médicale》2001,79(1):51-53
Encephalocel is leff frequent than spina bifida and anencephalia. Its incidence is 0.25@1000 births. It concern as much female than male. This neural defect is frequency associated to others malformations face (20%) squelette (17%), kidney (13%). In our study the ultra sound is performant in 82% of the cases. Encephalocel is still a lethal and severe abnormality. 相似文献
47.
Raad I Hachem R Hanna H Afif C Escalante C Kantarjian H Rolston K 《The Journal of antimicrobial chemotherapy》2004,53(4):646-649
OBJECTIVES: Quinupristin-dalfopristin and linezolid have been shown to be efficacious in the treatment of vancomycin-resistant Enterococcus faecium (VREF) infections. However, the two antibiotics have not been compared in terms of safety and efficacy in a prospective randomized study. The objective of this study was to compare the safety and efficacy of the two drugs in the treatment of VREF infections in cancer patients. PATIENTS AND METHODS: Forty cancer patients with VREF infection were randomized to receive linezolid 600 mg every 12 h or quinupristin-dalfopristin 7.5 mg/kg every 8 h. All patients were followed up for 30 days after discontinuation of study drugs. RESULTS: Linezolid and quinupristin-dalfopristin had comparable clinical responses (58% and 43%, respectively, P = 0.6). Myalgias and/or arthralgias occurred at a frequency of 33% in patients who received quinupristin-dalfopristin, but were not observed in the linezolid group (P = 0.03). In contrast, drug-related thrombocytopenia occurred in 11% of patients who received linezolid, but was not observed in the quinupristin-dalfopristin group (P = 0.2). CONCLUSION: In cancer patients, quinupristin-dalfopristin treatment is associated with a relatively high frequency of myalgias/arthralgias; however, profound thrombocytopenia might limit the choice of linezolid in a subpopulation of cancer patients. 相似文献
48.
49.
Fatina W. Dahadhah Mayyas Saleh Jaweesh Mazhar Salim Al Zoubi Manal Issam Abu Alarjah Mohamad Eid Hammadeh Houda Amor 《Andrologia》2021,53(8):e14139
Male infertility is a multifactorial condition associated with different genetic abnormalities in at least 15%–30% of cases. The purpose of this study was to identify suspected correlations between infertility and polymorphisms in mitochondrial NADH dehydrogenase subunits 3 and 4L (MT-ND3 and MT-ND4L) in subfertile male spermatozoa. Sanger sequencing of the mitochondrial DNA target genes was performed on 68 subfertile and 44 fertile males. Eight single nucleotide polymorphisms (SNPs) in MT-ND3 (rs2853826, rs28435660, rs193302927, rs28358278, rs41467651, rs3899188, rs28358277 and rs28673954) and seven SNPs in MT-ND4L (rs28358280, rs28358281, rs28358279, rs2853487, rs2853488, rs193302933 and rs28532881) were detected and genotyped. The genotypes and allele frequencies of the study population have shown a lack of statistically significant association between MT-ND3 and MT-ND4L SNPs and male infertility. However, no statistically significant association was found between the asthenozoospermia, oligozoospermia, teratozoospermia, asthenoteratozoospermia, oligoasthenoteratozoospermia and oligoteratozoospermia subgroups of subfertile males. However, rs28358278 genotype of the MT-ND3 gene was reported in the subfertile group but not in the fertile group, which implies a possible role of this SNP in male infertility. In conclusion, the investigated polymorphic variants in the MT-ND3 and MT-ND4L genes did not show any significant association with the occurrence of male infertility. Further studies are required to evaluate these findings. Moreover, the subfertile individuals who exhibit a polymorphism at rs28358278 require further monitoring and evaluation. 相似文献
50.
STUDY OBJECTIVES: To investigate whether atorvastatin decreases serum or leukocyte-produced CD40 ligand (CD40L) levels and whether these effects are dependent on reduction in low-density lipoprotein cholesterol (LDL) levels in people without overt dyslipidemia. DESIGN: Prospective pilot study. SETTING: University research center. SUBJECTS: Twenty-five normocholesterolemic volunteers (mean age 32 +/- 11 yrs; 15 women, 10 men) without cardiovascular disease. INTERVENTION: After a 2-week drug-free run-in period, subjects received atorvastatin 80 mg/day orally for 16 weeks. MEASUREMENTS AND MAIN RESULTS: All lipoprotein level measurements were performed with the subject in the fasting state. The CD40L concentrations were measured by immunofluorescence detection in serum and leukocyte culture supernates after 24-hour incubation, and treatment effect was analyzed. Baseline mean +/- SD total cholesterol, LDL, high-density lipoprotein cholesterol, and triglyceride levels were 179 +/- 33, 97 +/- 29, 62 +/- 20, and 102 +/- 69 mg/dl, respectively. Mean changes in each of these levels, respectively, after 16 weeks of atorvastatin were -34%, -59%, +3%, and -23%. The median serum CD40L level was lower at 16 weeks (2.3 ng/ml, interquartile range [IQR] 1.2-5.0 ng/ml) than at baseline (3.0 ng/ml, IQR 2.1-3.7 ng/ml), but the change was not significant (p=0.24). However, atorvastatin significantly lowered CD40L produced from leukocytes by 57% (21 pg/mg of protein [IQR 10-38 pg/mg] vs 49 pg/mg [IQR 21-149 pg/mg], p=0.045). Effects were independent of reduction in cholesterol levels. CONCLUSION: Although atorvastatin did not significantly lower serum CD40L levels, significant reduction in leukocyte production was seen independent of degree of LDL reduction. These pilot data suggest a potential benefit in normocholesterolemic individuals that should be further investigated, and that leukocyte CD40L concentrations should be considered in the drug response. 相似文献