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61.
We explored the effects of the nucleoside transport inhibitor draflazine on regional blood flow, O2 extraction capabilities, and tumor necrosis factor (TNF) release in acute endotoxic shock. Fourteen anesthetized and mechanically ventilated dogs received 2 mg/kg of Escherichia coli endotoxin and were divided into two groups. Seven dogs received 0.1 mg/kg of draflazine 30 min before endotoxin, and 7 dogs served as a control group. Draflazine decreased arterial pressure without influencing cardiac index. Mesenteric and portal blood flow and ileum mucosal perfusion increased, but renal blood flow dramatically decreased. After endotoxemia, the draflazine-treated dogs had a lesser fall in cardiac index, filling pressures, and left ventricular stroke work index, and a lesser increase in pulmonary vascular resistance. After fluid resuscitation, they had a consistently lower renal blood flow and ileum mucosal perfusion, but a higher mixed venous and hepatic oxygen saturation and arterial pH than the control group. When cardiac index was reduced by tamponade to study the O2 extraction capabilities, renal blood flow and ileum mucosal perfusion remained lower in the draflazine group. Draflazine did not influence whole-body O2 extraction capabilities, but it delayed the occurrence of liver O2 supply dependency as indicated by a significantly lower liver DO2crit (27.7 +/- 3.9 vs. 43.3 +/- 10.8 mL/min) and a higher O2ERcrit (62.7 +/- 9.5 vs. 42.5 +/- 7.1%) than controls (both P< 0.05). On the other hand, draflazine increased intestinal DO2crit (42.4 +/- 15.4 vs. 27.7 +/- 6.5 mL/min, P < 0.05) compared to the control group. TNF levels remained higher in the draflazine group than in the control group, particularly 3 and 4 h after endotoxin administration. We conclude that nucleoside transport inhibition with draflazine does not alter global and hepatosplanchnic hemodynamics but may decrease gut mucosal perfusion and renal blood flow. However, this intervention can improve liver O2 extraction capabilities in acute endotoxic shock. 相似文献
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63.
In patients with multifocal neuropathy with conduction block (CB), CBs located between the root and Erb's point are not detected in nerve conduction studies. We therefore examined whether the triple-stimulation technique (TST) might provide a useful means of detecting CB proximal to Erb's point. Clinical assessments, extensive nerve conduction studies (NCS), conventional transcranial magnetic stimulation, and TST were performed on 10 patients with multifocal motor neuropathy with CB (MMNCB) and 6 patients with Lewis-Sumner syndrome. Conduction blocks located proximal to Erb's point were detected in 9 patients. Of the CBs, 58% were associated with muscle weakness. The use of TST to detect proximal CB improved the sensitivity of the American Association of Neuromuscular and Electrodiagnostic Medicine criteria for definite or probable MMNCB from 60% to 90%. Thus, the TST is a useful means for detection of proximal CB and gives NCS considerable additional diagnostic power. 相似文献
64.
OBJECTIVE: The mechanism behind the epidemiologically evident inverse relation between Helicobacter pylori seropositivity and risk of oesophageal adenocarcinoma (OAC) remains obscure. Severe corpus gastritis is unlikely to be in the causal pathway. With the hypothesis of a uniformly low risk, the associations of OAC with duodenal ulcer and gastric ulcer were explored, both linked to H pylori infection but with different patterns of bacterial colonisation and intragastric acidity. Possible associations of oesophageal squamous cell carcinoma (OSCC) with these ulcer types were also addressed. DESIGN AND PATIENTS: Retrospective cohorts of 61,548 and 81,379 unoperated patients with duodenal ulcer and gastric ulcer, respectively, recorded in the Swedish Inpatient Register since 1965, were followed from the first hospitalisation until the date of any cancer, death, emigration, definitive surgery, or 31 December 2003. Standardised incidence ratios (SIRs), with 95% CIs, expressed relative risk of oesophageal cancer, compared with the Swedish population matched for age, sex and calendar period. RESULTS: Contrary to expectation, patients with duodenal ulcer had a significant 70% excess risk of OAC (SIR 1.7, 95% CI 1.1 to 2.5). Gastric ulcer was unrelated to OAC (SIR 1.1, 95% CI 0.6 to 1.7). Although duodenal ulcer was non-significantly associated with a small excess of OSCC (SIR 1.3, 95% CI 0.96 to 1.8), gastric ulcer was linked to 80% increased risk (SIR 1.8, 95% CI 1.4 to 2.3). CONCLUSION: The inverse association between H pylori and OAC does not pertain to all infections. The pattern of gastric colonisation and/or impact on acidity may be important. With the reservation for the possibility of confounding, this study also provides some support for the importance of intragastric environment in the aetiology of OSCC. 相似文献
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66.
Incidence and pattern of direct blunt neurovascular injury associated with trauma to the skull base 总被引:2,自引:0,他引:2
Feiz-Erfan I Horn EM Theodore N Zabramski JM Klopfenstein JD Lekovic GP Albuquerque FC Partovi S Goslar PW Petersen SR 《Journal of neurosurgery》2007,107(2):364-369
OBJECT: Skull base fractures are often associated with potentially devastating injuries to major neural arteries in the head and neck, but the incidence and pattern of this association are unknown. METHODS: Between April and September 2002, 1738 Level 1 trauma patients were admitted to St. Joseph's Hospital and Medical Center in Phoenix, Arizona. Among them, a skull base fracture was diagnosed in 78 patients following computed tomography (CT) scans. Seven patients had no neurovascular imaging performed and were excluded. Altogether, 71 patients who received a diagnosis of skull base fractures after CT and who also underwent a neurovascular imaging study were included (54 men and 17 women, mean age 29 years, range 1-83 years). Patients underwent CT angiography, magnetic resonance angiography, or digital subtraction angiography of the head and craniovertebral junction, or combinations thereof. RESULTS: Nine neurovascular injuries were identified in six (8.5%) of the 71 patients. Fractures of the clivus were very likely to be associated with neurovascular injury (p < 0.001). A high risk of neurovascular injury showed a strong tendency to be associated with fractures of the sella turcica-sphenoid sinus complex (p = 0.07). CONCLUSIONS: The risk of associated blunt neurovascular injury appears to be significant in Level 1 trauma patients in whom a diagnosis of skull base fracture has been made using CT. The incidence of neurovascular trauma is particularly high in patients with clival fractures. The authors recommend neurovascular imaging for Level 1 trauma patients with a high-risk fracture pattern of the central skull base to rule out cerebrovascular injuries. 相似文献
67.
Magdalini Moutaftsi Shahram Salek‐Ardakani Michael Croft Bjoern Peters John Sidney Howard Grey Alessandro Sette 《European journal of immunology》2009,39(3):717-722
The recent identification of a large array of different vaccinia virus‐derived CD8+ T‐cell epitopes offers a unique opportunity to systematically analyze the correlation between protective efficacy and variables such as kinetics of expression and function of viral proteins, binding affinity to MHC molecules, immunogenicity, and viral antigen processing/presentation. In the current study, 49 different H‐2b restricted epitopes were tested for their ability to protect peptide‐immunized C57Bl/6 mice from lethal i.n. challenge with vaccinia virus. The epitopes varied greatly in their ability to confer protection, ranging from complete protection with minimal disease to no protection at all. The function or kinetics of the viral antigen expression did not correlate with protective efficacy. However, binding affinity partially predicted protection efficacy and ultimately epitope immunogenicity and recognition of infected cells offered the best correlation. 相似文献
68.
Kajbafzadeh A Salmasi AH Payabvash S Arshadi H Akbari HR Moosavi S 《The Journal of urology》2007,177(3):1118-23; discussion 1123
PURPOSE: We report the evolution of endoscopic treatment of ectopic ureteroceles from the unroofing technique to a novel approach using concomitant ureterocele double puncture and intraureterocele fulguration. We also compare the results of different endoscopic modalities at a single center. MATERIALS AND METHODS: We reviewed the records of 46 children with ectopic ureteroceles who were treated endoscopically between 1995 and 2005. The patients were divided into 2 main groups. Group 1 included 17 patients who underwent common endoscopic treatments, including ureterocele incision (4 patients), single ureterocele puncture (4), and single puncture with insertion of a Double-J stent (9). Group 2 included 29 children who underwent ureterocele double puncture and fulguration of the anterior and posterior walls of the collapsed ureterocele after insertion of a Double-J stent into both punctured sites. We also managed concomitant vesicoureteral reflux by endoscopic injection of tricalcium phosphate ceramic into the subureteral region. RESULTS: Total success rates in group 1 were 0%, 25% and 33% in patients who underwent ureterocele incision, single ureterocele puncture and single puncture with insertion of a stent, respectively. Total success rate in group 2 was 90% (p<0.05). New onset vesicoureteral reflux developed in 8 patients (47%) in group 1, of which 6 were in ureterocele moieties, and in 8 patients (28%) in group 2, with none in a ureterocele moiety (p<0.01). A total of 13 patients (76%) in group 1 required open surgical intervention, compared to 3 (10%) in group 2 (p<0.05). CONCLUSIONS: This new endoscopic approach is highly effective in the treatment of children with ectopic ureteroceles. 相似文献
69.
BACKGROUND: The sliding hip screw is currently the most frequently used prosthesis used to fix trochanteric fractures of the hip. The 'tip-apex distance' (TAD) has been found to be predictive of hardware failure, with a larger TAD being associated with an increasing risk of 'cut-out'. Previous studies have either used 'hard-copy' radiographs and geometrical aids or a mixture of scanned hard-copy images and extra software to measure TAD. The current study describes a new method of tip-apex distance estimation using an entirely digital picture archiving and communication system (PACS). MATERIALS AND METHODS: Ten radiographs were measured for TAD by four surgeons of differing experience using the described measurement protocol, at two different time points (4 weeks apart). The results were then subjected to two-tailed t-tests to determine if they differed significantly. RESULTS: No tests attained significance (i.e. no statistical difference existed between the observers' measurements and no difference existed over time from a single observer's results). CONCLUSION: This study shows that TAD can be easily, accurately and, importantly, reproducibly measured using an entirely digitally based image capture and archiving system. The ease with which the measurements and calculations can be made will facilitate orthopaedic practitioners and trauma units in their auditing activities, and allows for quick TAD estimation in the 'X-ray meeting' environment. 相似文献
70.
Pourrabbani S Marra DE Iwasaki J Fincher EF Ronald LM 《Journal of drugs in dermatology : JDD》2007,6(3):293-296
Colloid milium (CM) is a rare cutaneous deposition disease with at least 3 distinct subtypes. The exact histogenesis of the condition is still unresolved and awaits definitive elucidation. Electron microscopy and immunohistochemical analysis have allowed the distinction of CM from clinically similar conditions such as amyloidosis. Successful treatment has been achieved with dermabrasion and, more recently, with ablative and fractional laser resurfacing of affected skin. 相似文献