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The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
5.
The latest remarkable technological advances in assisted reproduction,
which enable cryopreservation of spermatozoa, embryos and ovarian tissue,
raise difficult and debatable legal, social, ethical and moral issues
concerning the right to posthumous reproduction. Furthermore, reports on
the attitudes of the general public and of centres licensed for infertility
treatment in the United Kingdom found that the majority of women and
centres support the idea of posthumous reproduction. In this paper we
review the data published on this issue, and after considering the various
aspects, we conclude that each case should be discussed and authorized by a
multidisciplinary committee that includes physicians, clergy,
psychiatrists, psychologists, sociologists and other appropriate parties.
In our opinion, the main principles that should guide this committee would
allow posthumous reproduction in the context of marriage when a prior
consent exists. For unmarried persons, post-mortem donation of gametes
should be done only anonymously, if they are in agreement with existing
laws concerning infertility treatments in every country and after
appropriate consent and proper counselling. Moreover, any case which
involves consanguinity or a possibility of incest should be forbidden, both
for ethical and genetic reasons. In a case of pre-existing siblings, they
should be consulted and their informed consent should be granted in advance
so as to avoid legal problems in the inheritance of property.
相似文献
6.
JJ Favre Ph Chaffanjon JG Passagia JP Chirossel 《Surgical and radiologic anatomy : SRA》1995,17(2):133-138
Summary The authors report the results of a series of dissections and anatomic sections of the fronto-basal region of the brain and of the anterior cranial fossa in human cadavers. The constant presence of an arachnoidal cistern above the olfactory nerve was verified. The arachnoid separates from the pial membrane and forms a bridge with the ventral part of the olfactory bulb and tract, from the lateral edge of the olfactory sulcus to the medial edge of the gyrus rectus. The cistern is wide in its anterior portion, between the gyrus rectus and the olfactory bulb, and is reduced to a virtual slit in its posterior portion where the tract is lodged in the olfactory sulcus. The olfactory nerve can be separated without damaging fronto-basal arachnoidial adhesions over several centimeters. Dissection of this region after intravascular injection of colored media shows the constant presence of an artery destined to the olfactory bulb and tract. It originates either from the lateral surface of the anterior cerebral a. (segment A2), or from the medial fronto-basal a., and consistently provides terminal branches in front of the olfactory trigone in the medial olfactory sulcus. At their ventral extremity, the olfactory structures are therefore vascularised independently for several centimeters, from the lower face of the frontal lobe. The independent vascularisation of the olfactory nerve, the tenuous and easily detachable adhesions, and the actual presence of a true arachnoidal cistern all contribute to enabling surgical techniques which conserve olfactory function during anterior approaches.
Vascularisation du nerf olfactif. Rapports méningés et applications chirurgicales
Résumé Les auteurs rapportent les résultats d'une série de dissections et de coupes de la région fronto-basale de l'encéphale et de la fosse crânienne antérieure sur sujets cadavériques. La présence constante d'une citerne arachnoïdienne au dessus du n. olfactif a été vérifiée. L'arachnoïde se sépare du feuillet pial et passe en pont à la partie ventrale du bulbe et du tractus olfactifs, du bord latéral du sillon olfactif au bord médial du gyrus rectus. La citerne est large dans sa portion antérieure, entre le gyrus rectus et le bulbe olfactif, se réduit à une fente virtuelle postérieure lorsque le tractus se loge dans le sillon olfactif. Le n. olfactif peut être séparé sans dommage des adhérences arachnoïdiennes fronto-basales sur quelques centimètres. La dissection de cette région, après injection intravasculaire de masses colorées montre, de façon originale, la présence constante d'une artère destinée au tractus et au bulbe olfactifs. Elle naît soit de la face latérale de l'a. cérébrale antérieure (segment A2), soit de l'a. fronto-basale médiale, pour donner ses branches terminales toujours en avant du trigone olfactif dans le sillon orbitaire médial. Sur quelques centimètres à leur extrémité ventrale, les structures olfactives ont donc une vascularisation indépendante de la face inférieure du lobe frontal. L'indépendance vasculaire du n. olfactif, des adhérences ténues, facilement détachables, et la réalité vérifiée d'une véritable citerne arachnoïdienne permettent d'imaginer des techniques conservatrices de la fonction olfactive utilisées dans plusieurs indications de la chirurgie de la fosse crânienne antérieure.相似文献
7.
Preimplantation genetic diagnosis principles and ethics 总被引:4,自引:0,他引:4
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9.
Romieu R; Lacabanne V; Kayibanda M; Antoine B; Bennoun M; Chouaib S; Guillet JG; Viguier M 《International immunology》1997,9(10):1405-1413
There is now good evidence that cytokines contribute to the regulation of
tumor growth. The cytokine-driven modulation of tumor growth was
investigated during the progression of a hepatocellular carcinoma (HCC) in
SV40 large T tumor antigen transgenic mice. In vivo, an increased rate of
liver growth correlated with increased transforming growth factor
(TGF)-beta 1 mRNA expression, while the greatest amounts of tumor necrosis
factor (TNF)-alpha mRNA were detected earlier during tumor development.
Conversely, no particular alteration of IL-1 alpha, IL-1 beta, IL-6, IL-2,
IL-4 and IFN-gamma mRNA production could be reported. In vitro,
hepatocyte-like tumor cell lines established at two stages, either before
or after HCC differentiation, were characterized. The early-stage-derived
cell line produced TNF-alpha mRNA, but had barely detectable expression of
TGF-beta 1 mRNA, while later-stage- derived cell lines showed the
reciprocal pattern. All cell lines displayed a lack of sensitivity to
TNF-alpha, although some degree of sensitivity to TNF-alpha could be
observed in the presence of actinomycin-D or after treatment with
IFN-gamma. The early-stage- derived cell line was sensitive to the growth
inhibitory effects of TGF- beta 1, but late-stage-derived tumor cell lines
displayed a loss of sensitivity to TGF-beta 1 which correlated with the
increased expression of TGF-beta 1 mRNA. Altogether, this suggests that
tumor cells contribute to the discrete TNF-alpha and TGF-beta 1 expression
patterns during HCC progression. This model of HCC could be of valuable
interest to assess the impact of various immunotherapeutic strategies on
modulation of tumor growth.
相似文献
10.
MicroRNAs (miRNAs) are a class of noncoding RNAs found in organisms as evolutionarily distant as plants and mammals, yet most of the mRNAs they regulate are unknown. Here we show that the ability of an miRNA to translationally repress a target mRNA is largely dictated by the free energy of binding of the first eight nucleotides in the 5' region of the miRNA. However, G:U wobble base-pairing in this region interferes with activity beyond that predicted on the basis of thermodynamic stability. Furthermore, an mRNA can be simultaneously repressed by more than one miRNA species. The level of repression achieved is dependent on both the amount of mRNA and the amount of available miRNA complexes. Thus, predicted miRNA:mRNA interactions must be viewed in the context of other potential interactions and cellular conditions. 相似文献