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2.
Laser thermal angioplasty is a new technique. The longest follow-up is 3 years. It is used increasingly for the treatment of atheromatous disease of the femoropopliteal segment. The authors describe a case of successful recanalization of a completely occluded left external iliac artery using laser thermal angioplasty. The artery was approached through a left femoral dissection. The patient was discharged from the hospital on postoperative day 4 without claudication. The present indications and potential benefits and complications of this procedure are discussed. 相似文献
3.
Developmental changes in K+-selective channel activity during differentiation of the Purkinje neuron in culture 总被引:4,自引:0,他引:4
The cerebellar Purkinje neuron cultured from 20 d rat embryos is electrically inexcitable when immature, and acquires excitable membrane properties according to a programmed developmental sequence, thus providing a useful model for investigating mechanisms of CNS neuronal development. Using conventional patch-clamp techniques, we have characterized the the predominant classes of active K+-selective channels at a range of ages encompassing the entire developmental process from 5 to 29 d in vitro (DIV), and have shown pharmacologically that these channels are important contributors to the patterns of spontaneous activity generated by the Purkinje neurons. The 4 predominant classes of K+ channels that are active during steady-state depolarizing voltage commands are identified by unit conductances as the 27, 44, 70, and 100 pS channels, and show differences in several properties, including voltage dependence, sensitivity to tetraethylammonium chloride (TEA), mean open time, and time of appearance during development. Intracellular current-clamp recordings show that physiological maturation of the Purkinje neuron entails increases in the firing rate, the diversity of spike events that comprise spontaneous activity, and the sensitivity of spontaneous activity to disruption by the K+ channel blocker TEA. This increase in sensitivity to TEA correlates with the new expression of activity of the larger-conductance TEA-sensitive classes of K+ channel (70 and 100 pS types). These data show that developmental regulation of the activity of K+-selective channels contributes significantly to the ionic mechanisms that underlie the developmental transitions in spontaneous activity patterns in the Purkinje neuron. 相似文献
4.
Biocompatibility studies of the Anaconda stent-graft and observations of nitinol corrosion resistance. 总被引:3,自引:0,他引:3
Robert Guidoin Yvan Douville Michel F Baslé Martin King Georgi R Marinov Amidou Traoré Ze Zhang Fabien Guillemot Guy Dionne Ruwan Sumanasinghe André-Pierre Legrand Marie-France Guidoin Marie-Christine Porté-Durrieu Charles Baquey 《Journal of endovascular therapy》2004,11(4):385-403
PURPOSE: To validate the deployment, in vivo performance, biostability, and healing capacity of the Anaconda self-expanding endoprosthesis in a canine aortic aneurysm model. METHODS: Aneurysms were surgically created in 12 dogs by sewing a woven polyester patch onto the anterior side of the thoracic or abdominal aorta. Anaconda prostheses were implanted transfemorally for prescheduled periods (1 or 3 months). Aneurysm exclusion and stent-graft patency were monitored angiographically. Healing was assessed with histological analysis and scanning electron microscopy (SEM). Textile analysis determined the physical and chemical stability of the woven polyester material, while the biostability of the nitinol wires was evaluated with SEM and spectroscopy. RESULTS: All prostheses were intact at explantation. After 1 month, endothelial-like cells were migrating in a discontinuous manner both proximally and distally over the internal collagenous pannus at the device-host boundary. After 3 months, endothelialization had reached the midsections of the devices, with a thicker collagenous internal capsule. Patches of endothelial-like cells were sharing the luminal surface with thrombotic deposits. However, the wall of the device at the level of the aneurysm was generally poorly healed, with multiple thrombi scattered irregularly over the luminal surface. The polyester fabric was intact except for some filaments that were ruptured adjacent to the sutures and some abrasion caused by the nitinol wires. No evidence of corrosion was found on the nitinol stents. CONCLUSIONS: This Anaconda stent-graft has demonstrated its ability to exclude arterial aneurysms. The device used in this study was an experimental prototype, and the manufacturer has incorporated new immobilization features into the model for clinical use. The constituent materials appear to be suitable in terms of biocompatibility, biofunctionality, and short-term durability. 相似文献
5.
Personal Digital Assistants (PDAs) are a readily accessible source of information to aid in the delivery of patient care. A pilot group of five Family Nurse Practitioner students used PDAs to organize data and access information relevant to patient care. Utilization of the PDAs in the clinical setting provided practice guidelines, textbook information and protocols that were readily accessible. The PDA made it possible for students to utilize preexisting knowledge with additional learning resources. The PDAs were purchased with funds provided from a United States Department of Health and Human Services, Health Resources and Services Administration (HRSA) grant. 相似文献
6.
目的:探讨重症急性胰腺炎(SAP)的治疗效果。方法:采取回顾性总结方法对1992年1月~1997年5月收治的86例SAP病例资料,分析发病2周内非手术治疗和手术治疗的并发症发生率以及治愈率。结果:发现经早期非手术治疗使SAP特别是SAPⅡ型的病人并发症发生率大大降低,并提高了疾病的治愈率。结论:在ICU的严密监护下,对SAP患者采用全身支持治疗,使用抗胰酶制剂,胰腺休息治疗,以及预防性应用抗生素等早期非手术治疗取得明显的效果,值得提倡和推广。 相似文献
7.
Jean Bergeron Thierry Normand Adl Bharucha M. R. van Murtby Pierre Julien Claude Gagné Carole Dionne Marc de Braekeleer Daniel Brun Michael R. Hayden Paul J. Luplen 《Clinical genetics》1992,41(4):206-210
Familial lipoprotein lipase deficiency (FLD) is of particular interest to the French Canadian population of Québec since the largest concentration of homozygotes and carriers of this genetic disease in the world resides in this area. We have previously described a missense mutation (M-188) in the lipoprotein lipase (LPL) gene which was present in FLD patients belonging to different ancestries, including a number of French Canadians (Monsalve MV et al. J Clin Invest 1990: 86: 728-734). In the present report, we show that this mutation, although found in largest absolute numbers among French Canadians as compared to other groups in the world, accounts for only a small proportion (24%) of all the LPL mutant alleles in this population. The M-188 occurs either in the homozygote state or as a compound heterozygote with another LPL mutation. Analysis of geographic distribution indicates that the M-188 is more prevalent in western Québec, with the highest carrier rate in the Mauricie region. Genealogical reconstruction leads to the recognition of four founders for M-188, all emigrants from France to Québec in the 17th century. 相似文献
8.
The localization of a sauvagine (SV)/urotensin I (UI)-like material in the brain of the dogfish, Scyliorhinus canicula, was studied by immunohistochemical techniques, employing an antiserum raised in rabbit against synthetic SV which widely cross-reacts with UI. Positive cell bodies and nerve fibers were identified in the dorsocaudal hypothalamic region of the tuberculum posterius, in the nucleus sacci vasculosi and nucleus tuberculi posterioris. A dense network of immunoreactive axons was shown in the whole tuberculum posterius. These findings support the view that SV/UI-like peptides may be involved in neuromodulatory functions throughout the brain of cartilaginous fish. 相似文献
9.
Guanylin-like peptides regulate electrolyte/water transport through the epithelia. Moreover, these peptides possess antiproliferative activity and regulate the turnover of epithelial cells. In an earlier study we localized guanylin immunoreactivity in secretory ducts of adult rodent salivary glands. In this study we investigated the appearance and distribution pattern of this peptide during the development of rat salivary glands. Guanylin immunoreactivity appeared at the beginning of cell differentiation from solid bud, on embryonic day 17 in the submandibular and sublingual glands and after day 18 in the parotid gland. Guanylin immunoreactivity appeared first in ductal and acinar anlage: its cell distribution pattern and fate differed in these two compartments. In the duct cells guanylin immunoreactivity spread after the duct system developed, whereas in acinar cells it disappeared after cell differentiation. The guanylin immunoreactivity we detected in adult salivary duct cells accords with guanylins role in regulating electrolyte and water transport through the various epithelia. It does so by activating guanylate cyclase-C receptor, increasing intracellular cGMP concentration, and phosphorylating the cystic fibrosis transmembrane conductance regulator (CFTR) protein by the cGMP-dependent protein kinase II. This signaling cascade couples to the ductal electrolyte/water secretion and modulates finally the electrolyte composition of the saliva. On the other hand, CFTR is also involved in mechanisms of cell growth, by regulating apoptosis, and promoting cell differentiation. The early diffuse guanylin immunoreactivity we observed in ducts and acinar anlage, before the secretory set is operative, suggests guanylin has a role in cell differentiation. 相似文献
10.
To elucidate the main ontogenetic steps of galanin immunoreactivity within the extrinsic nerve supply of the alimentary tract, we undertook an immunohistochemical study of chicken embryo specimens. Fluorescence and streptavidin-biotin-peroxidase protocols were combined, using a galanin polyclonal antiserum, on transverse serial sections obtained from chicken embryos from embryonic Day 3 (E3) to hatching, and from 9-day-old newborn chicks. Galanin-immunoreactive cells were first detected at E3.5 within the pharyngeal pouch region, the nodose ganglion, the primary sympathetic chain, primitive splanchnic branches and the caudal portion of the Remak ganglion. At E5.5 galanin-immunoreactive cells and fibers appeared in the secondary (paravertebral) sympathetic chain, splanchnic nerves, peri- and preaortic plexuses, adrenal gland anlage and visceral nerves. Galanin-immunoreactive cells also lay scattered along the vagus nerve, and in the intermediate zone of the thoracolumbar spinal cord. At E18, galanin-immunoreactive cells and fibers were found along the entire Remak ganglion and around the gastrointestinal blood vessels. In post-hatching-9-day old chicks, the para- and prevertebral ganglia, but not the intermediate zone of the spinal cord, contained galanin-immunoreactive cells. Data indicate the presence of a consistent "galaninergic" nerve system supplying the chick embryonal gut wall. Whether this system has growth or differentiating role remains to be demonstrated. Its presence and distribution pattern in the later stages clearly support its well known role as a visceral neuromodulator of gut function. 相似文献