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排序方式: 共有938条查询结果,搜索用时 15 毫秒
1.
Therapeutic Consequences of Variation in Intraarterial Pressure Measurements After Iliac Angioplasty
Eric Tetteroo Cees Haaring Andries D. van Engelen Yolanda van der Graaf Willem P.T.M. Mali 《Cardiovascular and interventional radiology》1997,20(6):426-430
Purpose: To assess the accuracy of intraarterial measurement of transstenotic pressure gradients for the detection of hemodynamically
suboptimal iliac angioplasty.
Methods: In 14 patients, referred for diagnostic angiography, mean pressure gradients in the aorta and iliac artery were obtained
twice, using a double-sensor pressure catheter. Additional iliac measurements were performed during pharmacologically induced
flow augmentation. Repeatability was assessed by calculation of the mean difference plus standard deviation (MD ± SD) and
repeatability coefficient (2 × SD). These results were extrapolated to 137 iliac angioplasty procedures with secondary stenting
where there was a residual pressure gradient > 10 mmHg.
Results: MD ± SD for repeated measurements at rest and during flow augmentation were 0 ± 2 mmHg and 1 ± 3 mmHg, respectively. Repeatability
coefficients were 3 and 6 mmHg. Mean pressure gradients after hemodynamically insufficient angioplasty were 8 ± 7 mmHg at
rest and 17 ± 5 mmHg following vasodilatation. Inaccurate pressure recordings may have led to inappropriate stent placement
in less than 2.5%, and inappropriate denial of stent placement in less than 5% of the lesions.
Conclusion: Variability of intraarterial pressure measurements has little consequence in the detection of hemodynamically significant
stenosis after angioplasty.
Received: 0/00/00/Accepted: 0/00/00 相似文献
2.
Donald L. Miller M.D. 《Cardiovascular and interventional radiology》1987,10(2):111-113
Ivalon (polyvinyl alcohol) is a commonly used embolic agent, generally considered to be permanent. In a patient with the carcinoid
syndrome, embolization of hepatic metastases with Ivalon failed to produce permanent occlusion, and recurrent tumor was supplied
by many of the same small arteries identified on the original arteriogram. Occasionally, Ivalon may have only a temporary
occlusive effect. A possible explanation for this phenomenon is proposed. 相似文献
3.
Embolisation of a mycotic aneurysm of the anterior pancreaticoduodenal arcade was performed in an emergency situation using a microcatheter and tissue adhesive, after unsuccessful surgical therapy. The polymerising agent occluded the outflow vessel, the aneurysm and the feeding artery successfully.
Correspondence to: F. Hammer 相似文献
4.
Marwan H. Saab Douglas C. Smith Paul K. Aka Robert W. Brownlee J. David Killeen 《Cardiovascular and interventional radiology》1992,15(4):211-216
Percutaneous transluminal balloon angioplasty (PTA) was performed in 17 tibial arteries with an average cross-sectional area
stenosis of 92% (range 75–99%) in 13 patients (14 limbs) for limb salvage. In 4 of 14 lower extremities, PTA of femoropopliteal
arteries was also performed. Technical success with 50% or less residual stenosis was achieved in all 17 tibial vessels. At
approximately 2 months after PTA, clinical improvement had occurred in 10 of 14 limbs; no patient was made worse. Most recent
follow-up (mean 19 months, range 8–34 months) revealed continued satisfactory clinical success with no further vascular intervention
in 9 of these 10 limbs (one patient died). Short segmental stenoses, residual stenoses less than 40% following PTA, and absence
of diabetes or gangrene appear to be predictors of favorable clinical outcomes. Our results suggest that PTA of focal tibial
stenosis is an effective and safe treatment modality in properly selected patients and that wider use of PTA may be justified. 相似文献
5.
Chun Yuan Jay S. Tsuruda Kirk N. Beach Cecil E. Hayes Marina S. Ferguson Charles E. Alpers Thomas K. Foo D. Eugene Strandness 《Journal of magnetic resonance imaging : JMRI》1994,4(1):43-49
Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation. 相似文献
6.
Salvatore J. A. Sclafani M.D. Michael Herskowitz M.D. Susan Rachlin M.D. Stanley Z. Trooskin M.D. 《Emergency radiology》1995,2(6):380-383
Traumatic communications between the hepatic artery or its branches and the portal vein or its tributaries usually are clinically
occult until the late sequelae of portal hypertension, such as esophageal and mesenteric varices, ascites, or congestive heart
failure, become manifest. The authors describe the early diagnosis of such a lesion by computed tomography. The CT findings
included a hepatic hematoma and, more significantly, diffuse thickening of the small and large bowel wall. This thickening
represents vascular congestion of the bowel caused by acute portal hypertension prior to the development of decompressing
portal collateral circuits.
When this CT finding is not associated with other signs of intestinal ischemia or infarction, it should suggest portal hypertension
and lead to arteriography for diagnosis and therapy of arterioportal fistula. 相似文献
7.
Grisk O Lother U Gabriëls G Rettig R 《Pflügers Archiv : European journal of physiology》2005,449(4):364-371
Renal transplantation experiments have shown that the kidney contributes to chronic sympathectomy-induced arterial pressure reduction in spontaneously hypertensive rats (SHR). The underlying mechanisms are currently unclear but may include alterations in the function of small renal arteries. Neonatal SHR were sympathectomized by intraperitoneal guanethidine injections and removal of adrenal medullary tissue. Controls were sham- or hydralazine-treated. At 12 weeks of age, distal interlobar artery segments were investigated using small-vessel wire myography. Vessels from sympathectomized animals showed increased sensitivity to noradrenaline (NE). Vasopressin- and endothelin-1-induced vasoconstriction was similar in all groups (as reflected by the pD2, i.e. –logEC50, where EC50 is the molar concentration of agonist eliciting a half-maximal response). Maximum vasopressin-induced tension was similar in all groups while endothelin-1-induced maximum tension was significantly higher in sympathectomized than in sham-treated SHR. The sensitivity of NE-induced vasoconstriction to extracellular Ca2+ did not differ between groups while sensitivity to L-type Ca2+ channel activation was significantly higher in both sympathectomized and hydralazine-treated animals than in sham-treated animals. Endothelium-dependent and independent vasodilation were similar in all groups. Sequential blockade of NO-synthase and cyclooxygenase had similar effects in all groups. In conclusion, neonatal sympathectomy does not induce any changes in the function of isolated proximal renal resistance arteries from SHR that could explain the blood pressure lowering effect of a kidney graft from sympathectomized SHR. 相似文献
8.
J. Pillet B. Enon P. Cronier Ph. Mercier P. Moreau J. M. Chevalier 《Surgical and radiologic anatomy : SRA》1982,4(4):307-314
Summary The arteries of the gut, and in particular in the inferior mesenteric artery (a. mesenterica inferior), normally play a minimal role in supplying blood to the lower limbs. However, this is far from being the case in aorto-iliac obstruction. The anatomical anastomoses between the intestinal arterial system and the arteries of the lower limb hypertrophy and in one case out of ten become predominant.In the present study the path taken and the relations of the collaterals of the intestinal arteries and of their anastomoses have been traced, and several collateral pathways are described.
Rôle des artères mésentériques dans la revascularisation artérielle des membres inférieurs
Résumé Les artères digestives, et en particulier l'artère mésentérique inférieure (a. mesenterica inferior), jouent à l'état normal un rôle minime dans la vascularisation des membres inférieurs. Il n'en est pas de même en cas d'oblitération aorto-iliaque. Les anastomoses anatomiques entre le système artériel digestif et les artères du membre inférieur s'hypertrophient et, dans un cas sur 10, deviennent prédominantes.Dans cette étude, le trajet et les relations des collatérales des artères digestives et leurs anastomoses sont étudiés. Plusieurs voies collatérales sont possibles.相似文献
9.
Mark M. Kockx Floris L. Wuyts Norbert Buyssens Rita M. Van Den Bossche Guido R. De Meyer Hidde Bult Arnold G. Herman 《Virchows Archiv : an international journal of pathology》1993,422(4):293-299
Intima formation in vessels, spontaneous or experimentally induced, is generally characterized by the presence of longitudinally orientated smooth muscle cells (LSMC). During an experiment of neo-intima induction in carotid arteries in rabbits, by application of a nonconstrictive silastic cuff, a study was performed to investigate the presence of LSMC in the systemic and pulmonary circulations, in both elastic and muscular arteries. Three patterns could be distinguished: intimai cushions in muscular arteries, single or small groups of LSMC in the intima in elastic and larger muscular arteries, and intra-medially located layers or columns of LSMC in the aorta, the pulmonary artery, at the bifurcation of the aorta and around orifices of branches. In order to understand this peculiar orientation a biomechanical approach was used: this showed that near the lumen the circumferential stress is 4.5 times higher than the longitudinal. Because the cell surface of the smooth muscle cells exposed to this stress per unit vessel length is much less in the longitudinal than in the circular direction we conclude that the LSMC align in the direction which allows them to cope most effectively with the mechanical stresses. 相似文献
10.
Fluid and solid mechanical implications of vascular stenting 总被引:10,自引:0,他引:10
Vascular stents have emerged as an effective treatment for occlusive vascular disease. Despite their success and widespread use, outcomes for patients receiving stents are still hampered by thrombosis and restensosis. As arteries attempt to adapt to the mechanical changes created by stents, they may in fact create a new flow-limiting situation similar to that which they were intended to correct. In vitro fluid mechanics and solid mechanics studies of stented vessels have revealed important information about how stents alter the mechanical environment in the arteries into which they are placed. Adverse nonlaminar flow patterns have been demonstrated as well as remarkably high stress concentrations in the vessel wall. In vivo studies of stented vessels have also shown a strong relationship between stent design and their dynamic performance within arteries. Alterations in pressure and flow pulses distal to the stent have been observed, as well as regional changes in vascular compliance. Considering the influence of flow and stress on the vascular response and the suboptimal clinical outcomes associated with stenting, knowledge gained from stent/artery mechanics studies should play an increasingly important role in improving the long-term patency of these devices. © 2002 Biomedical Engineering Society.
PAC2002: 8719Rr, 8780-y, 8719Uv 相似文献