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1.
Die Anaesthesiologie - Auch wenn für Anästhesiologen über Jahrzehnte die Prophylaxe und Therapie postoperativer Schmerzen im Rahmen des postoperativen Patientenkomforts an vorderster...  相似文献   
2.

Objective

Low psoas muscle area is shown to be an indicator for worse postoperative outcome in patients undergoing vascular surgical. Additionally, it has been associated with longer durations of hospital stay in patients with cancer who undergo surgery and subsequently greater health care costs in Europe and the United States. We sought to evaluate this effect on hospital expenditure for patients undergoing vascular repair in a health care system with universal access.

Methods

Skeletal muscle mass was assessed on preoperative abdominal computed tomography scans of patients undergoing open aortic aneurysm repair in a retrospective fashion. The skeletal muscle index (SMI) was used to define low muscle mass. Health care costs were obtained for all patients and the relationship between a low SMI and higher costs was explored using linear regression and cross-sectional analysis.

Results

We included 156 patients (81.5% male) with a median age of 72 years undergoing elective surgery for infrarenal abdominal aortic aneurysm in this analysis. The median SMI for patients with low skeletal muscle mass was 53.21 cm2/kg and for patients without, 70.07 cm2/kg. Hospital duration of stay was 2 days longer in patients with low skeletal muscle mass as compared with patients with normal (14 days vs 11 days; P = .001), as was duration of intensive care stay (3 days vs 1 day; P = .01). The median overall hospital costs were €10,460 higher for patients with a low SMI as compared with patients with a normal physical constitution (€53,739 [interquartile range, €45,007-€62,471] vs €43,279 [interquartile range, €39,509-€47,049]; P = .001). After confounder adjustment, a low SMI was associated with a 14.68% cost increase in overall hospital costs, for a cost increase of €6521.

Conclusions

Low skeletal muscle mass is independently associated with higher hospital as well as intensive care costs in patients undergoing elective aortic aneurysm repair. Strategies to reduce this risk factor are warranted for these patients.  相似文献   
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OBJECTIVE: To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint. MATERIALS AND METHODS: Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images. RESULTS: The best image quality was obtained with X-rays (p < 0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p < 0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p < 0.001) and X-rays were the worst (p < 0.05). CONCLUSIONS: Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures.  相似文献   
6.
In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only.  相似文献   
7.
Hepatic ketogenesis and peripheral ketone body utilization in the ruminant   总被引:2,自引:0,他引:2  
Hepatic and alimentary ketogenesis occur at similar rates in fed, nonpregnant, nonlactating goats, sheep and dairy cows. Alimentary ketogenesis begins to diminish within 24 h after fasting but compensatory increases in hepatic ketogenesis maintain total splanchnic release and, therefore, no change in circulating concentrations of ketone bodies is observed. By the third day of fast the gut is utilizing acetoacetate and beta-hydroxybutyrate and alimentary ketogenesis has ceased. Hepatic ketogenesis of both ketone bodies accelerates rapidly due to portal-drained visceral and hindquarter lipolysis and subsequent hepatic fatty acid uptake and total circulating concentrations are doubled. During pregnancy and lactation in sheep and cows alimentary ketogenesis is maintained as long as digestible organic matter intake is constant. Hepatic and total splanchnic release of beta-hydroxybutyrate increases in late gestation and early lactation. Again, this is due to increased portal-drained visceral and hindquarter free fatty acid release and hepatic free fatty acid uptake. Hindquarter uptake of both ketones during late gestation is similar to the ratio observed in nonpregnant fed sheep but the percentage of utilization decreases, perhaps reflecting partitioning to uteroplacental tissues. Hindquarter uptake of both ketone bodies in sheep increases in early lactation due to increased circulating concentrations because extraction ratios are similar to those of fed animals. Ketosis during pregnancy in sheep and lactation in cows may be prevented by beta-hydroxybutyrate stimulation of pancreatic insulin production. However, an insulin-independent intrahepatic mechanism apparently occurs in sheep.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
A new method for the selective spin labeling of left- or right-sided supplying arteries of the brain without the need for additional RF coils is demonstrated. A clinical 1.5 T scanner was used. The spatial selectivity of the labeling process is based on the limited coverage of the excitation field of a standard send/receive head coil together with an oblique positioning of the labeling plane. A computer simulation was used to optimize key labeling parameters under the condition of laminar flow. The validity of the computer model results was confirmed by MRI measurements with a flow model. For human studies, a double-inversion continuous arterial spin labeling (CASL) sequence was modified to allow for arbitrary positioning of the labeling plane. The obtained perfusion-weighted images showed a clear delineation of the perfusion territories of the selected arteries in the anterior circulation of the brain and good gray/white matter contrast.  相似文献   
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Junctional structures formed by two parts of the plasma membrane of the same cardiac muscle cell were observed in ventricular myocardium of: a) patients with neoplasms, aortic valvular disease or idiopathic hypertrophic subaortic stenosis and b) dogs subjected to prolonged normothermic anoxic cardiac arrest. Most of these structures had features of desmosomes; other, more complex structures had components with features of desmosomes, fasciae adherentes and nexuses, and, therefore, resembled intercalated discs. These intracytoplasmic junctions were localized to: a) the peripheral cytoplasm at the sides or ends of cells, b) narrow invaginations of plasma membranes, c) narrow zones of deep, broad plasmalemmal invaginations and d) narrow branches of T tubules. In patients with idiopathic hypertrophic subaortic stenosis or aortic valvular disease and in the dogs subjected to anoxic cardiac arrest, intracytoplasmic junctions were observed in hypertrophied or degenerated muscle cells which were located in areas of fibrosis and which showed loss of contact with adjacent cells. In patients with neoplasms, intracyto-plasmic junctions were found in degenerated cells which were located in areas of interstitial edema and which also showed loss of contact with adjacent cells. Our observations suggest that remodeling of cell surfaces following loss of intercellular contact is the most likely mechanism of formation of intracytoplasmic junctions.  相似文献   
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