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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
4.
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
5.
Preimplantation genetic diagnosis principles and ethics 总被引:4,自引:0,他引:4
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Comparison of anatomic and neurophysiological methods for subthalamic nucleus targeting 总被引:13,自引:0,他引:13
Zonenshayn M Rezai AR Mogilner AY Beric A Sterio D Kelly PJ 《Neurosurgery》2000,47(2):282-92; discussion 292-4
OBJECTIVE: The subthalamic nucleus (STN) has recently become the surgical target of choice for the treatment of medically refractory idiopathic Parkinson's disease. A number of anatomic and physiological targeting methods have been used to localize the STN. We retrospectively reviewed the various anatomic targeting methods and compared them with the final physiological target in 15 patients who underwent simultaneous bilateral STN implantation of deep brain stimulators. METHODS: The x, y, and z coordinates of our localizing techniques were analyzed for 30 STN targets. Our final targets, as determined by single-cell microelectrode recording, were compared with the following: 1) targets selected on coronal magnetic resonance inversion recovery and T2-weighted imaging sequences, 2) the center of the STN on a digitized scaled Schaltenbrand-Wahren stereotactic atlas, 3) targeting based on a point 13 mm lateral, 4 mm posterior, and 5 mm inferior to the midcommissural point, and 4) a composite target based on the above methods. RESULTS: All anatomic methods yielded targets that were statistically significantly different (P < 0.001) from the final physiological targets. The average distance error between the final physiological targets and the magnetic resonance imaging-derived targets was 2.6 +/- 1.3 mm (mean +/- standard deviation), 1.7 +/- 1.1 mm for the atlas-based method, 1.5 +/- 0.8 mm for the indirect midcommissural method, and 1.3 +/- 1.1 mm for the composite method. Once the final microelectrode-refined target was determined on the first side, the final target for the contralateral side was 1.3 +/- 1.2 mm away from its mirror image. CONCLUSION: Although all anatomic targeting methods provide accurate STN localization, a combination of the three methods offers the best correlation with the final physiological target. In our experience, direct magnetic resonance targeting was the least accurate method. 相似文献
8.
Gonzales AJ; Christensen JG; Preston RJ; Goldsworthy TL; Tlsty TD; Fox TR 《Carcinogenesis》1998,19(7):1173-1183
9.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献
10.
Characterization of the insulin-like growth factor axis in a human hepatoma cell line (PLC) 总被引:4,自引:0,他引:4
Scharf JG; Schmidt-Sandte W; Pahernik SA; Ramadori G; Braulke T; Hartmann H 《Carcinogenesis》1998,19(12):2121-2128