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71.
Moeenaldeen Al-Sayed Faiqa Imtiaz Osama A Alsmadi Mohammed S Rashed Brian F Meyer 《BMC medical genetics》2006,7(1):86-5
Background
3-Hydroxy-3-Methylglutaric aciduria (3HMG, McKusick: 246450) is an autosomal recessive branched chain organic aciduria caused by deficiency of the enzyme 3-Hydroxy-3-Methylglutaryl CoA lyase (HL, HMGCL, EC 4.1.3.4). HL is encoded by HMGCL gene and many mutations have been reported. 3HMG is commonly observed in Saudi Arabia. 相似文献72.
Alam MM Kobayashi N Uehara N Watanabe N 《Microbial drug resistance (Larchmont, N.Y.)》2003,9(2):109-121
High-level antiseptic resistance of Staphylococcus aureus is mediated by multidrug efflux pumps encoded by qacA and qacB genes. We investigated distribution and genomic diversity of these antiseptic resistance genes in a total of 522 clinical strains of S. aureus isolated recently in a Japanese hospital. The qacA/B gene was detected in 32.6% of methicillin-resistant S. aureus (MRSA) and 7.5% of methicillin-susceptible S. aureus (MSSA), whereas the low-level resistance gene smr, which was examined simultaneously, was detected at lower frequencies in both MRSA (3.3%) and MSSA (5.9%). Epidemiologic typing of S. aureus isolates suggested that higher prevalence of qacA/B in MRSA may be due to spread of a single predominant MRSA strain carrying qacA/B in the hospital. Restriction fragment length polymorphism (RFLP) analysis indicated higher prevalence of the qacB-type gene (59.3%) than the qacA-type gene (40.7%) among the qacA/B genes detected. Nucleotide sequencing analysis revealed the presence of two genetic variants in qacA (V1 and V2) and four variants in qacB (V1-V4) that differ from the qacA prototype in pSK1 by 1-5 nucleotides and 7-9 nucleotides, respectively. Although most strains with qacA-V1, qacA-V2, qacB-V3, and qacB-V4 showed high-level resistance to ethidium bromide (EB)(MIC > 100 microg/ml), all of the S. aureus isolates carrying qacB-V1 and qacB-V2 showed lower MICs of EB and some monovalent cationic antiseptic substances. By analysis of the genomic organization of the qacA/B downstream region, divergent forms of this region rearranged with an insertion of IS256 or IS257 were found primarily for qacB. The downstream region of qacA-V1 was suggested to be an evolutionary origin for other divergent forms. These findings indicated that both qacA and qacB are prevalent in recent clinical isolates, especially in MRSA, and these genes consist of variable genetic variants that may be responsible for different resistance levels against antiseptic substances. 相似文献
73.
Lovering Ruth; Middleton-Price Helen R.; O'Reilly Marie-Anne J.; Genet Sally A.; Parkar Mohammed; Sweatman Angela K.; Bradley Linda D.; Alterman Lesley A.; Malcolm Sue; Morgan Gareth; Levinsky Roland J.; Kinnon Christine 《Human molecular genetics》1993,2(2):139-141
Genetic linkage analysis has been instrumental in mapping thegene for X-linked agammaglobulinemia (XLA) to the proximal longarm of the human X chromosome, to Xq22. Due to the relativerarity of this disease the localization of the gene within Xq22has remained imprecise. We have investigated twenty-nine familiesaffected by XLA and have found no recombinants with the DXS178locus in over 30 informative meioses. DXS178 is now the mostreliable and informative locus for use in pre-natal diagnosisand carrier detection of XLA. In addition, we have identifiednew closely linked proximal and distal flanking markers forXLA, DXS442 and DXS101, respectively. These loci are separatedby 2cM, considerably reducing the extent of DNA within whichthe XLA locus can be contained. This will open up the way formore directed positional cloning efforts for the isolation ofthe XLA gene. 相似文献
74.
S. M. Hussain Qadri Mohammed N. Al-Ahdal G. Yasmeen Khan 《Medical microbiology and immunology》1989,178(3):135-141
Clinical specimens from 317 patients suspected of cytomeglovirus infection were examined by immunofluorescence (IF) using monoclonal antibodies and by a biotinylated DNA probe kit after cell culture isolation. Of the 317 samples, 68 were positive by culture isolation. Of these 67 were IF positive when the cytopathic effect (CPE) was 1+ or less, whereas 56 gave positive results with DNA probes when the CPE was 2+. A further 83 specimens were examined directly by immunoperoxidase histopathology (IHP), IF and the DNA probe kit: 26 of these were positive by IHP examination, 25 by IF and only 6 by DNA probes. The sensitivity of the DNA probe kit was not satisfactory when the clinical tissue specimens were directly examined. However, the sensitivity improved considerably to 82% if the specimens were propagated first in cell culture. The IF method detected the virus before and after cell culture isolation equally well (96%–98.5%). Compared to the IF method, the DNA probe kit is costly and requires more labor and time.This paper was presented in part at the 88th annual meeting of the American Society for Microbiology, Miami Beach, FL, USA, 1988 相似文献
75.
76.
Viollet L Zarhrate M Maystadt I Estournet-Mathiaut B Barois A Desguerre I Mayer M Chabrol B LeHeup B Cusin V Billette De Villemeur T Bonneau D Saugier-Veber P Touzery-De Villepin A Delaubier A Kaplan J Jeanpierre M Feingold J Munnich A 《European journal of human genetics : EJHG》2004,12(6):483-488
Chronic distal spinal muscular atrophy (Chronic DSMA, MIM (*)607088) is a rare autosomal recessive disorder characterized by a progressive motor weakness and muscular atrophy, predominating in the distal parts of the limbs. A form of Chronic DSMA gene has been previously mapped to chromosome 11q13 in the 10.3 cM interval defined by loci D11S1889 and D11S1321. By linkage analysis in 12 European Chronic DSMA families, we showed that a disease gene maps to chromosome 11q13.3 (Z(max)=6.66 at theta=0.00 at the DSM4 locus) and suggested that this condition is genetically homogeneous. Recombination events allowed us to reduce the genetic interval to a 2.6 cM region, telomeric to the IGHMBP2 gene, excluding this gene as the disease causing gene in Chronic DSMA. Moreover, partial linkage disequilibrium was found between three rare alleles at loci D11S1369, DSM4 and D11S4184 and the mutant chromosome in European patients. Analysis of the markers at these loci strongly suggests that most Chronic DSMA chromosomes are derived from a single ancestor. Refinement of the Chronic DSMA locus will hopefully allow to test candidate genes and lead to identification of the disease-causing mutations. 相似文献
77.
Abdel Hakim Saad Rashika El Ridi Suher Zada Nasri Badir 《Developmental and comparative immunology》1984,8(4):835-844
Lymphocytes of thymus, spleen, peripheral blood (PB) and bone marrow (BM) collected from adult lizards, were cultured for 24 hr in the presence of 10?3M hydrocortisone acetate (HC) in order to assess the effect of in vitro HC on lizard T and B cell viability. The results indicated that HC induced stepwise, time-dependent mortality of the majority of thymocytes carrying T cell specific antigen(s) (TSA), 30–50% of T cells of spleen, PB and BM, and of a proportion of splenic B lymphocytes. Administration of 1 mg/g body weight HC to adult . lead to depletion of all TSA+ thymocytes. In contrast, T lymphocytes in the peripheral lymphoid compartments revealed both sensitivity and resistance to HC; similarly, B lymphocytes constituted susceptible and resistant subpopulations. 相似文献
78.
Relationship between ROS production, apoptosis and DNA denaturation in spermatozoa from patients examined for infertility 总被引:24,自引:0,他引:24
Moustafa MH Sharma RK Thornton J Mascha E Abdel-Hafez MA Thomas AJ Agarwal A 《Human reproduction (Oxford, England)》2004,19(1):129-138
BACKGROUND: The aim of this study was to examine the role of apoptosis and reactive oxygen species (ROS) in inducing DNA damage in ejaculated spermatozoa. METHODS: We examined ejaculated spermatozoa from 31 patients examined for infertility and 19 healthy donors for apoptosis, production of ROS and DNA damage using annexin V binding, chemiluminescence assay and sperm chromatin structure assay. RESULTS: The percentage of spermatozoa that underwent apoptosis in the whole ejaculate and mature fraction was higher in the patients than in the donors (P<0.001 and P=0.009, respectively). Levels of ROS in the whole ejaculate and immature fraction were higher in the patients than in the donors (P=0.002 and P=0.009). Apoptosis was significantly correlated with ROS within patients in the whole ejaculate [r (95% confidence interval)=0.53 (0.19-0.86)] and in the mature [0.71 (0.39-1.00)] and immature spermatozoa [0.75 (0.45-1.00)]. Only apoptosis and the DNA fragmentation index (DFI) were significantly correlated within patients in the whole ejaculate [0.57 (0.18-0.97)]. CONCLUSIONS: DNA damage may be induced by oxidative assault. Apoptosis may not contribute significantly to the DNA damage. 相似文献
79.
Bernard Boutevin Grard Rigal Mohammed El Asri Tahar Lakhlifi 《Macromolecular chemistry and physics.》1995,196(3):891-902
In the case of water soluble polymers, the use of size exclusion chromatography (SEC) for the determination of the molecular weight involves numerous difficulties. In order to analyse and determine the molecular weight of acrylic acid telomers we have first tried to obtain a satisfactory and reproducible separation. In this particular case, low-molecular-weight standards are not commercially available. Therefore, we decided to prepare standards based on acrylic acid, either by telomerization with a fluorinated telogen or by polymerization with an initiator bearing a fluorinated group. A calibration curve was obtained from the standards. Telomers of acrylic acid with thioglycolic acid were analysed. This is a general method for determination of DP n by SEC when there is no standard for the polymers. It can be used in a wide range of DP n from 1 to 700. 相似文献
80.
Fine-needle aspiration biopsy findings in three cases of chromophobe cell carcinoma are described and correlated with histologic and ultrastructural observations. In addition, comparisons are made with three cases each of oncocytoma and granular cell carcinoma. The cells in aspiration smears from chromophobe cell carcinoma closely correlated with histologic pattern of three cell types which were not present in oncocytomas and granular cell carcinomas. These cells had prominent cell borders, and their cytoplasm was either opaque and granular (type I) or variably translucent and reticular (type II and III). Ultrastructurally, the translucent areas within the cytoplasm contained large numbers of microvesicles which were unique to chromophobe cell carcinoma and were not seen in other neoplasms. Fine-needle aspiration may be used to diagnose chromophobe cell carcinoma and distinguish it from other related renal neoplasms. © 1995 Wiley-Liss, Inc. 相似文献