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11.
Van de Velde H; De Vos A; Joris H; Nagy ZP; Van Steirteghem AC 《Human reproduction (Oxford, England)》1998,13(11):3160-3164
In human in-vitro fertilization (IVF), the oocytes are surrounded by
cumulus and corona cells at the time of insemination so that their maturity
cannot easily be evaluated. The best IVF results are obtained if the
oocytes are inseminated 2-6 h after retrieval. In the intracytoplasmic
sperm injection (ICSI) procedure, the oocytes are denuded by enzymatic and
mechanical treatment in order to be able to perform the injection. As a
consequence, the nuclear maturity of the oocytes can be evaluated and only
those that have extruded the first polar body are injected. However,
metaphase-II oocytes that have not yet reached cytoplasmic maturity cannot
be recognized. The purpose of this study was to investigate the effect of
different timing of cumulus- corona cell removal and injection on the
outcome of ICSI. For this we allowed the oocytes to complete in-vitro
cytoplasmic maturation in two different culture conditions: (i) surrounded
by their cumulus and corona cells or (ii) totally denuded. We performed
three different studies on sibling oocytes obtained after a standardized
buserelin/human menopausal gonadotrophin (HMG) protocol. We investigated
the effect of early (1-2 h after retrieval) and late (5-6 h after
retrieval) oocyte denudation and injection on the survival and
fertilization of the injected oocytes and on embryo cleavage after
fertilization. We found no statistically significant differences between
early and late injection, indicating that after a standardized
buserelin/HMG protocol the metaphase-II oocytes do not need time for
further cytoplasmic maturation. Furthermore, a different timing of
cumulus-corona cell removal has no effect on the outcome of ICSI,
suggesting that the surrounding cells are not necessary for survival,
fertilization and cleavage after ICSI.
相似文献
12.
Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献
13.
14.
Percoll gradient centrifugation can be omitted in sperm preparation for intracytoplasmic sperm injection 总被引:4,自引:3,他引:4
De Vos A; Nagy ZP; Van de Velde H; Joris H; Bocken G; Van Steirteghem A 《Human reproduction (Oxford, England)》1997,12(9):1980-1984
Prior to intracytoplasmic sperm injection (ICSI), seminal fluid is
currently washed out from the ejaculated semen and further sperm selection
is carried out by a discontinuous Percoll gradient. Possible deleterious
effects from the sperm-separating substance Percoll on sperm function or
embryo cleavage after in-vitro fertilization (IVF) have, to our knowledge,
not yet been reported and the use of Percoll has been widely accepted in
IVF. In this study, we examined whether the omission of the Percoll step in
the sperm preparation has any influence on the outcome of the ICSI
procedure. Two methods of sperm preparation for ICSI were compared in a
controlled study on sibling oocytes: washing the semen sample once,
followed by a Percoll gradient centrifugation versus washing the sperm
sample twice without a Percoll gradient centrifugation. The mean
fertilization rates were similar for the two sperm preparation methods:
78.2 +/- 21.4 and 75.0 +/- 24.1% respectively of the intact oocytes
displaying two pronuclei. Cleavage rates did not differ statistically
between the two groups. Whereas in both groups similar percentages of
excellent, good and poor quality embryos were obtained, the percentage of
fair quality embryos was significantly higher in the group without Percoll
(16.3 +/- 20.1 versus 9.1 +/- 15.7%). However, no statistical differences
were observed in either the percentage of transferable embryos or in the
percentage of embryos actually transferred or frozen in the two groups. In
conclusion, spermatozoa from ejaculates that are washed out from the
seminal fluid without any further selection can be used for ICSI without
any adverse effect on fertilization and embryo cleavage.
相似文献
15.
Lafay-Cousin L Soenen V Mazingue F Preudhomme C Laï JL Andrieux J 《Cancer Genetics and Cytogenetics》2004,150(2):153-155
Recurrent chromosomal rearrangements involving the 11q23 region have been described in various hematologic malignancies. Among these rearrangements, translocations are the most common mechanism involving the mixed lineage leukemia gene (MLL). Few cases of insertion have been reported and, to our knowledge, none of them involved MLL and chromosome 1. We report a complex karyotype in a childhood acute myelomonocytic leukemia (AML M4) involving the 11q23 region with an insertion between chromosomes 1 and 11 in addition to a translocation between chromosomes 11 and 22. This translocation was clarified by fluorescence in situ hybridization (FISH) analysis: 46,XY,ins(1;11)(q22q23;q13q23),t(11;22)(q13;q11q12). This finding also underlines the complementary contribution of conventional cytogenetic and FISH analysis to detect karyotypic complex abnormalities. 相似文献
16.
G. Majno I. Joris E. S. Handler J. Desemone J. P. Mordes A. A. Rossini 《The American journal of pathology》1987,128(2):210-215
BB rats develop spontaneous autoimmune diabetes mellitus characterized morphologically by insulitis, an inflammatory lymphocytic infiltration of the islets of Langerhans. To investigate the role of the vascular endothelium of the pancreas in this destructive process, the authors injected diabetes-prone (DP) and diabetes-resistant (DR) BB/Wor rats as well as other nondiabetic strains of rats with Monastral blue B, a colloidal pigment that identifies leaky microvasculature. They found evidence of a venular defect limited to the pancreas that is specific to the BB rat. Light- and electron-microscopic evidence suggests that this defect is due to a population of trapped (marginating) intravascular monocytes, which may be activated by the colloidal pigment and release vasoactive mediators. 相似文献
17.
Vermeesch JR Melotte C Salden I Riegel M Trifnov V Polityko A Rumyantseva N Naumchik I Starke H Matthijs G Schinzel A Fryns JP Liehr T 《European journal of medical genetics》2005,48(3):319-327
A dysmorphic patient was shown to carry a small supernumerary marker chromosome. Multicolor, centromere-multicolor and regular FISH experiments proved the marker to be an analphoid 12pter derived isochromosome. Microdissection of the marker followed by reverse painting and array CGH analysis showed that the isochromosome contains approximately 6 Mb of 12pter-12p13.31 derived sequence. This is only the second report of a marker with a neocentromere 12pter and the molecular fine mapping of the duplicated region further refines the 12p region defining the Pallister-Killian syndrome phenotype. In addition, we show the feasibility of using microdissected chromosomes or chromosomal fragments to molecularly map the chromosomal breakpoints on array CGH. This technology may aid in the identification of chromosomal translocation breakpoints. 相似文献
18.
19.
20.
Temporal information in the responses of auditory neurons to sustained sounds has been studied mostly with periodic stimuli, using measures that are based on Fourier analysis. Less information is available on temporal aspects of responses to nonperiodic wideband sounds. We recorded responses to a reference Gaussian noise and its polarity-inverted version in the auditory nerve of barbiturate-anesthetized cats and used shuffled autocorrelograms (SACs) to quantify spike timing. Two metrics were extracted from the central peak of autocorrelograms: the peak-height and the width at halfheight. Temporal information related to stimulus fine-structure was isolated from that to envelope by subtracting or adding responses to the reference and inverted noise. Peak-height and halfwidth generally behaved as expected from the existing body of data on phase-locking to pure tones and sinusoidally amplitude-modulated tones but showed some surprises as well. Compared with synchronization to low-frequency tones, SACs reveal large differences in temporal behavior between the different classes of nerve fibers (based on spontaneous rate) as well as a strong dependence on characteristic frequency (CF) throughout the phase-locking range. SACs also reveal a larger temporal consistency (i.e., tendency to discharge at the same point in time on repeated presentation of the same stimulus) in the responses to the stochastic noise stimulus than in the responses to periodic tones. Responses at high CFs reflect envelope phase-locking and are consistent with previous reports using sinusoidal AM. We conclude that the combined use of broadband noise and SAC analysis allow a more general characterization of temporal behavior than periodic stimuli and Fourier analysis. 相似文献