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41.
Zusammenfassung Eingehende Stellungnahme zur konstitutionellen Dysostosis enchondralis. Anerkennung als Dachbegriff und Befürwortung desselben. Umgrenzung seines derzeitigen Inhalts, als welcher die Dysostosistypen Ribbing und Morquio, die Dysostosis multiplex v. Pfaundler-Hurler, die Cystinkrankheit sowie bisher mehr-minder vereinzelt dastehende Beobachtungen zu nennen sind. Stellungnahme zu manchen der letzteren und zur multiplen Epiphysenstörung. Ablehnung röntgenoskopischer Unterscheidungsmöglichkeit zwischen Formen mit epiphysär, meta- und epiphysär bzw. metaphysär lokalisierten Veränderungen als klinisches Ordnungsprinzip.. —Ins Einzelne gehende Erörterung der Abgrenzung zwischen Dysostosis Morquio und dem lipoidfernen Symptomenkomplex der klassischen sowie der Spätform der Pfaundler-Hurlerschen Krankheit. Skeletröntgenoskopische Abtrennung zwischen Späthurler und Morquio erscheint vorerst unmöglich. Tabellarische Zusammenstellung der Unterschiede zwischen den genannten Affektionen. — Abschließend kurze Ausführungen zur Pleonosteosis familiaris Léri.  相似文献   
42.
Follicular fluid proteoglycans play an important role in human oocyte maturation, including the development of a fluid-filled compartment and maintenance of the hypocoagulative state of the follicular fluid. Human xylosyltransferase (EC 2.4.2.26, XT) is the key enzyme in the biosynthesis of glycosaminoglycan chains in proteoglycans and is secreted into body fluids together with large proteoglycans. We investigated the XT activities in human follicular fluid and granulosa-lutein cells from women undergoing IVF procedures. The mean XT activity was determined as 17.7 mU/l, which is 20-fold higher than in serum and the highest XT activity ever found in body fluids. Cultured human granulosa-lutein cells secreted large amounts of XT (14.52 micro U/10(6) cells), indicating that these cells are the main source of this enzyme in human follicular fluid. The XT from human follicular fluid was found to be associated with large chondroitin sulphate-containing proteoglycans. Furthermore, heparin was shown to bind strongly to the follicular fluid XT and to inhibit its enzyme activity. These findings indicate that XT may play a role in maintaining the haemostatic potential of the follicular fluid.  相似文献   
43.
Vagal preganglionic efferents to the rat stomach were labeled anterogradely by injecting the fluorescent carbocyanine dye DiA into the dorsal motor nucleus in vivo. Enteric neurons were labeled in toto by intraperitoneal administration of Fluorogold, and neurochemically characterized by simultaneous single- and double-label immunocytochemistry. Single peptide immunocytochemistry revealed that in all three major areas of the stomach, about one-third of all gastrin-releasing peptide immunoreactive (GRP-IR) neurons in the myenteric plexus, received vagal contacts. Because the proportion of GRP-IR neurons was 32% in the fundus, 23% in the corpus, and only 8% in the antrum, the absolute number of vagally contacted GRP-IR neurons per cm2 was also different. Double-label immunocytochemistry revealed colocalization of vasoactive intestinal peptide immunoreactivity (VIP-IR) in 45%, and of enkephalin immunoreactivity (ENK-IR) in about 30%, of the GRP-IR myenteric neurons. A subpopulation of myenteric neurons colocalized GRP-IR and VIP-IR and projects almost exclusively to the gastrin cell-rich basal mucosa of the antrum and the oxyntic mucosa of the corpus. Another subpopulation containing GRP-IR, but not VIP-IR, projects mainly to the myenteric plexus itself and the external muscle layers, particularly the longitudinal muscle. A third group of neurons containing VIP-IR but not GRP-IR projects heavily to the circular muscle layer, the muscularis mucosae, and to other myenteric neurons. Vagal input to these three subpopulations seems not to be selective, in that an equal proportion of about 20 to 30% of each group was vagally contacted. Vagal inputs to these neurochemically and topographically distinct enteric neurons provide the basis for the physiological vagal control of gastrin release, gastric acid secretion, and gastric motility. © 1996 Wiley-Liss, Inc.  相似文献   
44.
45.

Objective

To evaluate the effects of different suture materials and techniques on soft tissue in relation to defined tensions and time points.

Materials and methods

Two bovine intestine samples, 4?×?4?cm size and ~3?mm thickness, were adapted with interrupted and continuous techniques using three types of suture materials: Vicryl (polyglactin 910), PDS II (polydioxanone), and V-Loc 180 (knotless, barbed polyglyconate). Four stitches or loops 9?mm apart with three knots, and 10?mm end length were performed by one gynecologist. Forces were applied from 6 newtons (N) to 14?N continuously. Outcome measures included breakage of tissue, tearing of thread, and shortening of the end length of thread. They were evaluated immediately and then at first, third, and fifth minute.

Results

Tissue breakage using No. 3/0 suture materials appears in the applied force from 10?N. polydioxanone causes more tissue tearing than polyglactin 910. The least to withstand tension is knotless polyglyconate. Interrupted stitches hold the sutured sites better than continuous stitches in all groups of threads. Shortening of the knotless polyglyconate end length by half took place with 6?N force.

Conclusion

Simulating reparation of colpotomy, the ex vivo study supports that polyglactin 910 appears better in holding soft tissue than polydioxanone and knotless polyglyconate.  相似文献   
46.
The ability of the brain to adjust to changing environments and to recover from damage rests on its remarkable capacity to adapt through plastic changes of underlying neural networks. We show here with an eye movement paradigm that a lifetime of plastic changes can be extended to several hours by repeated applications of theta burst transcranial magnetic stimulation to the frontal eye field of the human cortex. The results suggest that repeated application of the same stimulation protocol consolidates short-lived plasticity into long-lasting changes.  相似文献   
47.
The methanolic extract of rhizomes of Cyperus articulatus, a plant used in traditional medicine in Africa and Latin America for many diseases, possesses anticonvulsant activity in mice. This extract protected mice against maximal electroshock (MES)- and pentylenetetrazol (PTZ)-induced seizures. It also delayed the onset of seizures induced by isonicotinic acid hydrazide and strongly antagonized N-methyl-D-aspartate-induced turning behavior. The ED(50) for protection against seizures was 306 (154-541) mg/kg intraperitoneally (i.p.) for the PTZ test and 1005 (797-1200) mg/kg i.p. for the MES test. The ED(50) of methanolic extract against N-methyl-D-aspartate-induced turning behavior was 875 (623-1123) mg/kg i.p. C. articulatus L. methanolic extract protected 54% of mice from seizures induced by strychnine at the dose of 1000 mg/kg i.p. but had no or a moderate effect only against picrotoxin- or bicuculline-induced seizures. With these effects, the rhizome of C. articulatus L. possesses anticonvulsant properties in animals that might explain its use as a traditional medicine for epilepsy in Africa.  相似文献   
48.
Neural stem cells (NSCs) generate new neurons throughout life in the mammalian hippocampus. The distinct developmental steps in the course of adult neurogenesis, including NSC activation, expansion, and neuronal integration, are increasingly well characterized down to the molecular level. However, substantial gaps remain in our knowledge about regulators and mechanisms involved in this biological process. This review highlights three long-standing unknowns. First, we discuss potency and identity of NSCs and the quest for a unifying model of short- and long-term self-renewal dynamics. Next, we examine cell death, specifically focusing on the early demise of newborn cells. Then, we outline the current knowledge on cell integration dynamics, discussing which (if any) neurons are replaced by newly added neurons in the hippocampal circuits. For each of these unknowns, we summarize the trajectory of studies leading to the current state of knowledge. Finally, we offer suggestions on how to fill the remaining gaps by taking advantage of novel technology to reveal currently hidden secrets in the course of adult hippocampal neurogenesis.  相似文献   
49.
The present study characterizes the time course of social conflict analgesia and its reversibility by opioid antagonist drugs in the C57BL/6 and DBA/2 inbred strains of mice and examines the relationship between alterations in brain and pituitary levels of β-endorphin-like immunoreactivity (β-ELIR) and the antinociception elicited by social stress. Data revealed statistically strain differences in regard to β-ELIR in control animals. The pituitary content of β-ELIR was higher in DBA/2, while the values in the periaqueductal grey (PAG) and in the amygdala were higher in C57BL/6 mice. No interstrain differences were found in the hypothalamus. Exposure to 50 attack bites resulted in a 6-fold higher analgesia in DBA/2 mice and in a strain-dependent fall of ELIR in pituitary (27%) and PAG (23%). PAG but not pituitary β-ELIR levels in C57BL/6 mice correlated positively with the increase in tail-flick latency after attack. Mere confrontation with a non-aggressive opponent failed to induce analgesia and was associated in C57BL/6 mice with a significant reduction in the β-ELIR content of both the pituitary and the PAG. The data are discussed in terms of genotype-dependent sensitivity of the β-endorphin system to stress and its relation to analgesia.  相似文献   
50.
Summary The effects of six prototype anticonvulsant drugs, phenytoin, carbamazepine, midazolam, phenobarbital, ethosuximide and sodium valproate, were evaluated in two different experimental models of epileptiform activity using the in vitro slice preparation from the rat hippocampus. The relative potencies of the agents were determined: a) in the complete absence of synaptic transmission by recording spontaneous burst firing from the CA 1 pyramidal cell layer in a low calcium high magnesium solution and b) during blocked synaptic inhibition by observing the activity of each drug upon orthodromically evoked population spikes in penicillin containing medium. The rank order of potencies was a) in low Ca2+: carbamazepine, phenytoin, midazolam, phenobarbital, valproate, ethosuximide; b) in penicillin containing medium: midazolam, phenobarbital, carbamazepine, phenytoin, valproate, ethosuximide. These observations illustrate that the use of multiple paradigms is warranted when examining the mechanisms of action of new anticonvulsants.  相似文献   
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