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651.
652.
653.
Dr. Steven M. Lipson Patrick Costello Susan Forlenza Bruce Agins Katarina Szabo 《Current microbiology》1990,20(1):39-42
In an effort to reduce the number of unreadable MRC-5 cell culture monolayers (i.e., monolayers that are obscured by an opaque film or are detached from their coverslips), urine specimens were subjected to low-speed (500 g for 10 min at 4°C) centrifugation prior to their inoculation into shell vials for the detection of cytomegalovirus (CMV). A total of 182 urine specimens obtained from patients suffering from ARC or AIDS were subjected to routine centrifugation culture and to preinoculation centrifugation. Cytomegalovirus recovery among the two specimen-treatment procedures was determined by counting the number of immunofluorescent MRC 5-positive cells. Eleven of 19 positive specimens were in accord in both systems. However, routinely treated (i.e., without preinoculation centrifugation) specimens were difficult to read specifically among those specimens that were cloudy or opaque. Cytome-galovirus was recovered in 18 of the 19 positive specimens that were subjected to the preinoculation centrifugation procedure. Only 12 of 19 positive specimens were identified following direct inoculation of untreated urine into shell vials. The additional preinoculation centrifugation step is appropriate for the removal of obfuscating amorphous substances from the assay system without compromising CMV detection rates. 相似文献
654.
J D Young C E Costello A Van Langenhove E Haber G R Matsueda 《International journal of peptide and protein research》1983,22(3):374-380
For immunochemical purposes, a cyclic 12-peptide was synthesized to model the gamma-gamma-chain cross-link site in human fibrin. The model was based upon the structure proposed by Chen & Doolittle (Biochemistry (1971) 10, 4486-4491) which is characterized by two reciprocating epsilon-(gamma-Glu)Lys bonds between adjacent fibrin gamma-chains oriented in an antiparallel manner. To achieve the antiparallel orientation of the peptide backbone, Pro and Gly were inserted at positions 6 and 7 of the linear 12-peptide: acetyl-Gly-Glu-Gln-His-His-Pro-Gly-Gly-Gly-Ala-Lys-Gly-amide. The insertions were made to facilitate a reverse turn of the peptide during the last synthetic step, which was formation of the epsilon-(gamma-Glu)Lys bond between Glu at position 2 and Lys at position 11 with diphenylphosphorylazide. The resulting cyclic peptide represented half of the symmetrical cross-linked region in clotted fibrin. Following purification by HPLC, both linear and cyclic 12-peptides were analyzed by fast atom bombardment mass spectrometry. Abundant molecular protonated ions were observed for both peptides. In addition, the amino acid sequence of the linear peptide and the location of the epsilon-(gamma-Glu)Lys bond in the cyclized peptide could be verified. 相似文献
655.
656.
Esther Munalula‐Nkandu Paul Ndebele Seter Siziya JC Munthali 《Developing world bioethics》2015,15(3):248-256
We conducted a study to review the consenting process in a vaginal Microbicide feasibility study conducted in Mazabuka, Zambia. Participants were drawn from those participating in the microbicide study. A questionnaire and focus group discussion were used to collect information on participants understanding of study aims, risks and benefits. Altogether, 200 participants took part in this study. The results of the study showed that while all participants signed or endorsed their thumbprints to the consent forms, full informed consent was not attained from most of the participants since 77% (n = 154) of the participants had numerous questions about the study and 34% (n = 68) did not know who to get in touch with concerning the study. Study objectives were not fully understood by over 61% of the participants. Sixty four percent of the participants were not sure of the risks of taking part in the microbicide study. A significant number thought the study was all about determining their HIV status. Some participants were concerned that their partners were not on the trial as they were convinced that being on the study meant that that they had a lifetime protection from HIV infection. The process of obtaining consent was inadequate as various phases of the study were not fully understood. We recommend the need for researchers to reinforce the consenting process in all studies and more so when studies are conducted in low literacy populations. 相似文献
657.
Gyorgy Csako Rene Costello Ejaz A Shamim Terrance P O'Hanlon Anthony Tran Daniel J Clauw H James Williams Frederick W Miller 《Arthritis research & therapy》2007,9(5):R95
Prior studies have suggested abnormalities of serum proteins, including paraproteins, in women with silicone implants but
did not control for the presence of connective-tissue disease (CTD). This retrospective case–control study, performed in tertiary-care
academic centers, assessed possible alterations of serum proteins, including paraproteins, in such a population. Seventy-four
women with silicone implants who subsequently developed CTD, and 74 age-matched and CTD-matched women without silicone implants,
were assessed in the primary study; other groups were used for additional comparisons. Routine serum protein determinations
and high-sensitivity protein electrophoresis and immunofixation electrophoresis were performed for detection of paraproteins.
Women with silicone implants, either with or without CTD, had significantly lower serum total protein and α1-globulin, α2-globulin, β-globulin, γ-globulin, and IgG levels compared with those without silicone implants. There was no significant
difference, however, in the frequency of paraproteinemia between women with silicone implants and CTD (9.5%) and age-matched
and CTD-matched women without silicone implants (5.4%) (odds ratio, 1.82; 95% confidence interval, 0.51–6.45). Paraprotein
isotypes were similar in the two groups, and the clinical characteristics of the 13 women with paraproteinemia were comparable
with an independent population of 10 women with silicone breast implants, CTD, and previously diagnosed monoclonal gammopathies.
In summary, this first comprehensive study of serum proteins in women with silicone implants and CTD found no substantially
increased risk of monoclonal gammopathy. Women with silicone implants, however, had unexpectedly low serum globulin and immunoglobulin
levels, with or without the subsequent development of CTD. The causes and clinical implications of these findings require
further investigation. 相似文献
658.
Avise JC; Shapira JF; Daniel SW; Aquadro CF; Lansman RA 《Molecular biology and evolution》1983,1(1):38-56
We address the problem of the possible significance of biological
speciation to the magnitude and pattern of divergence of asexually
transmitted characters in bisexual species. The empirical data for this
report consist of restriction endonuclease site variability in maternally
transmitted mitochondrial DNA (mtDNA) isolated from 82 samples of
Peromyscus polionotus and P. leucopus collected from major portions of the
respective species' ranges. Data are analyzed together with previously
published information on P. maniculatus, a sibling species to polionotus.
Maps of restriction sites indicate that all of the variation observed can
be reasonably attributed to base substitutions leading to loss or gain of
particular recognition sites. Magnitude of mtDNA sequence divergence within
polionotus (maximum approximately equal to 2%) is roughly comparable to
that observed within any of five previously identified mtDNA assemblages in
maniculatus. Sequence divergence within leucopus (maximum approximately
equal to 4%) is somewhat greater than that within polionotus. Consideration
of probable evolutionary links among mtDNA restriction site maps allowed
estimation of matriarchal phylogenies within polionotus and leucopus.
Clustering algorithms and qualitative Wagner procedures were used to
generate phenograms and parsimony networks, respectively, for the
between-species comparisons. Three simple graphical models are presented to
illustrate some conceivable relationships of mtDNA differentiation to
speciation. In theoretical case I, each of two reproductively defined
species (A and B) is monophyletic in matriarchal genealogy; the common
female ancestor of either species can either predate or postdate the
speciation. In case II, neither species is monophyletic in matriarchal
genotype. In case III, species B is monophyletic but forms a subclade
within A which is thus paraphyletic with respect to B. The empirical
results for mtDNA in maniculatus and polionotus appear to conform closely
to case III. These theoretical and empirical considerations raise a number
of questions about the general relationship of the speciation process to
the evolution of uniparentally transmitted traits. Some of these
considerations are presented, and it is suggested that the distribution
patterns of mtDNA sequence variation within and among extant species should
be of considerable relevance to the particular demographies of speciation.
相似文献
659.
S G Boots M A Franklin B Dunlavey J Costello C Lipsitz M R Boots K S Rogers 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1976,151(2):316-320
Isophthalic acid, 5-carboxy-, 5-hydroxy-, 5-methoxy-, 5-fluoro-, 5-bromo-, 5-cyano-, and 5-methylisophthalic acid were inhibitors competitive with L-glutamate for bovine liver glutamate dehydrogenase. The extent of inhibition by the derived compounds was not much greater than that obtained with the parent compound, isophthalic acid. A plot of pKi versus pH showed the presence of an ionizable group (pKa 7.4-7.8) at the enzyme active site which interacted with the substitutent at the 5 position of the substituted isophthalates. 相似文献
660.