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61.
Woo K  Farber A  Doros G  Killeen K  Kohanzadeh S 《Journal of vascular surgery》2007,46(1):94-99; discussion 100
INTRODUCTION: Although autogenous brachial-basilic upper arm transpositions (BVT) have been extensively utilized, there has been significant disparity in published patency rates. Very little is known about the efficacy of autogenous brachial-cephalic upper arm transpositions (CVT). We evaluated our experience with transposed upper arm arteriovenous fistulas (tAVF) in order to assess patency and identify factors that affect efficacy. We then compared our tAVF patients with a cohort of upper arm arteriovenous grafts (AVG). METHODS: A retrospective review was conducted of tAVF performed at our institution from 1998 to 2004. The tAVF group consisted of 119 BVT and 71 CVT procedures. We compared these with 164 AVG. tAVF were placed only for veins >/=2.5 mm in diameter by duplex ultrasonography. RESULTS: Mean follow-up was 28 months. With the exception of mean vein diameter, the patients in the BVT and CVT groups had similar demographic parameters and complication rates. Primary and secondary patency rates were 52% and 62% at 5 years for BVT and 40% and 46% at 5 years for CVT, respectively (P = NS). Multivariate analysis revealed that hemodialysis dependence at the time of fistula placement and history of previous upper arm access independently affected primary patency. History of upper torso dialysis catheters independently affected secondary patency. Comparison of the tAVF and AVG groups revealed that tAVF patients were significantly younger, more likely to be male, less likely to be African American (AA) and less likely to have a history of previous AV access. The primary patency rate for tAVF was significantly higher than for AVG: 48% vs 14% at 5 years (P < .001). The secondary patency rate for tAVF was also significantly higher than for AVG: 57% vs 17% at 5 years (P < .001). Among the tAVF procedures, 9% required one or more revisions to maintain secondary patency, compared to 51% with the AVG group (P < .001). Multivariate analysis revealed that presence of AVG and a history of previous upper arm access negatively affected primary and secondary patency. CONCLUSIONS: Autogenous BVT and CVT have similar, high patency rates. Transposed upper arm arteriovenous fistulas have higher patency rates than upper arm AVG and require significantly fewer revisions. Our data strongly support the contention that as long as the patient is a candidate for an upper arm tAVF, based on anatomical criteria, a tAVF should always be considered before an AVG.  相似文献   
62.
A murine monoclonal antibody (MA 123) was selected by screening 153 supernatants of hybridoma cells secreting anti-human platelet antibodies for their ability to inhibit the fibrinogen-induced aggregation of chymotrypsin-treated platelets. MA 123 inhibited the binding of 125I-fibrinogen to ADP-stimulated intact human platelets and to platelets treated with chymotrypsin or pronase. Moreover, it inhibited the fibrinogen-induced aggregation of these platelet suspensions. The degree of inhibition was similar in each of the three types of platelets tested. The interactions of MA 123 with the 125I-labeled surface components of intact and chymotrypsin-treated platelets were studied by immunoprecipitation using Staphylococcus aureus coated with goat anti-mouse IgG, followed by SDS-polyacrylamide gel electrophoresis and autoradiography. MA 123 precipitated the glycoprotein IIb-glycoprotein IIIa (GPIIb-GPIIIa) complex from the surface of detergent solubilized intact human platelets; and it precipitated GPIIIa from the surface of chymotrypsin-treated platelets. Partially purified GPIIIa was also immunoprecipitated by MA 123. Our data suggest that the exposure of fibrinogen receptors by ADP, chymotrypsin or pronase, is associated with alterations of GPIIIa on the platelet surface.  相似文献   
63.

Objective

Despite vast improvement in the field of vascular surgery, elective abdominal aortic aneurysm (AAA) repair still leads to perioperative death. Patients with asymptomatic AAAs, therefore, would benefit from an individual risk assessment to help with decisions regarding operative intervention. The purpose of this study was to describe such a 30-day postoperative (POD) risk prediction model using American College of Surgeons National Surgical Quality Improvement Project (NSQIP) data.

Methods

The NSQIP database (2005-2011) was queried for patients undergoing elective AAA repair using open or endovascular techniques. Clinical variables and known predictors of mortality were included in a full prediction model. These variables included procedure type, patient's age, functional dependence and comorbidities, and surgeon's specialty. Backward elimination with alpha-level of 0.2 was used to construct a parsimonious model. Model discrimination was evaluated in equally sized risk quintiles.

Results

The overall mortality rate for 18,917 elective AAA patients was 1.7%. In this model, surgeon's specialty was not predictive of POD. The most significant factors affecting POD included open repair (odds ratio [OR], 2.712; 95% confidence interval [CI], 2.119-3.469; P < .001), age >70 (OR, 2.243; 95% CI, 1.695-3.033; P < .001), functional dependency (OR, 2.290; 95% CI, 1.442-3.637; P < .001), creatinine above 2.0 mg/dL (OR, 2.1; 95% CI, 1.403-3.142; P < .001) and low hematocrit levels (OR, 2.157; 95% CI, 1.365-3.408; P = .001).The discriminating ability of the NSQIP model was reasonable (C-statistic = 0.751) and corrected to 0.736 after internal validation. The NSQIP model performed well predicting mortality among risk-group quintiles.

Conclusions

The NSQIP risk prediction model is a robust vehicle to predict POD among patient undergoing elective AAA repair. This model can be used for risk stratification of patients undergoing elective AAA repair.  相似文献   
64.
65.
Ultrasound (US) has a significant role in diagnostic breast imaging. It is most commonly used as an adjunctive test in characterizing lesions detected by other imaging modalities or by clinical examination. US is recognized as the modality of choice in the evaluation of women who are symptomatic and younger than 30 years of age, pregnant, or lactating. Combined mammography and US appear to have a role in screening high-risk populations. The use of standard Breast Imaging Reporting and Data System US lexicon is helpful in guiding the differentiation between benign and malignant sonographic signs. Biopsy is warranted when benign features are absent or for any feature consistent with malignancy, despite other benign findings. Whole breast and axillary US are useful in assessing tumour extension, multifocality, and the status of axillary lymph nodes. US is the modality of choice for guiding interventional breast procedures. The role of US as a guidance tool for nonoperative breast treatment is being investigated.  相似文献   
66.
67.

Objective

Ipsilateral antegrade access (AA) is an alternative access option for contralateral retrograde access (RA) in treating infrainguinal occlusive disease. Our goal was to assess whether AA is associated with higher access site complications.

Methods

The Vascular Quality Initiative database was searched from 2010 to 2017 for all infrainguinal peripheral vascular interventions. Cases without access through the common femoral artery or those with multiple accesses were excluded. Access types were classified on the basis of whether the approach was AA or RA. Propensity matching and multivariable analyses were performed to determine the effect of AA on access site complications.

Results

There were 45,816 access events identified, 6600 (14.4%) AA and 39,216 (85.6%) RA cases. Patients with AA were older (70.7 vs 69.1 years) and more frequently male (66.5% vs 59.1%), white (79.4% vs 74.6%), and on Medicare (58.4% vs 56%); they were more likely to have end-stage renal disease (12.1% vs 11%), and they were less frequently obese (29.3% vs 36.1%) and less likely to be currently smoking (25.5% vs 28.7%), to be diabetic (56% vs 59.8%), to have chronic obstructive pulmonary disease (20.7% vs 21.8%), and to ambulate independently (69.8% vs 72.5%; P < .05 for all). Patients with AA were more likely to have a history of a prior percutaneous vascular intervention (9.3% vs 7%), inflow bypass (6.2% vs 1.8%), and leg bypass (12.6% vs 8.9%; P < .001 for all). The AA technique was more frequently used in the setting of tissue loss (51.8% vs 45.1%) and for tibial intervention (46.3% vs 35.3%; P < .001 for both). There were no significant differences between AA and RA in overall hematoma (3% vs 2.7%; P = .21) or hematoma requiring intervention (0.4% vs 0.4%; P = .75) rates. There was no significant difference in access site occlusion or stenosis between AA and RA (0.2% vs 0.3%; P = .68). These findings were confirmed with 2:1 matching based on preoperative data and type of intervention. Multivariable analysis demonstrated that AA is not associated with increased risk of any hematoma (odds ratio [OR], 1.15; 95% confidence interval [CI], 0.98-1.35; P = .082) or hematoma requiring intervention (OR, 0.88; 95% CI, 0.57-1.35; P = .56). Multivariable analysis of the matched data confirmed these findings between AA and RA for hematoma (OR, 0.88; 95% CI, 0.73-1.06; P = .17) and hematoma requiring intervention (OR, 1.17; 95% CI, 0.7-1.95; P = .55).

Conclusions

AA is safe, and it was not found to be associated with increased access site complications, such as hematoma, in the large Vascular Quality Initiative sample. This approach remains a viable alternative to traditional RA.  相似文献   
68.
69.
Little is known about the familial aggregation of intermittent claudication (IC). Our objective was to examine whether parental IC increased the risk of IC in adult offspring, independent of the established cardiovascular risk factors. We evaluated the Offspring Cohort Participants of the Framingham Heart Study who were ≥30 years old, cardiovascular disease free, and had both parents enrolled in the Framingham Heart Study (n = 2,970 unique participants, 53% women). Pooled proportional hazards regression analysis was used to examine whether the 12-year risk of incident IC in offspring participants was associated with parental IC, adjusting for age, gender, diabetes, smoking, systolic blood pressure, total cholesterol, high-density lipoprotein cholesterol, and antihypertensive and lipid treatment. Of the 909 person-examinations in the parental IC history group and 5,397 person-examinations in the no-parental IC history group, there were 101 incident IC events (29 with parental IC history and 72 without a parental IC history) during follow-up. The age- and gender-adjusted 12-year cumulative incidence rate per 1,000 person-years was 5.08 (95% confidence interval [CI] 2.74 to 7.33) and 2.34 (95% CI 1.46 to 3.19) in participants with and without a parental IC history. A parental history of IC significantly increased the risk of incident IC in the offspring (multivariable adjusted hazard ratio 1.81, 95% CI 1.14 to 2.88). The hazard ratio was unchanged, with an adjustment for the occurrence of cardiovascular disease (hazard ratio 1.83, 95% CI 1.15 to 2.91). In conclusion, IC in parents increases the risk of IC in adult offspring, independent of the established risk factors. These data suggest a genetic component of peripheral artery disease and support future research into genetic causes.  相似文献   
70.
Axillosubclavian vessel injury (ASVI) is associated with high morbidity and mortality. Most studies are single-center experiences of small numbers of patients with penetrating injury. We assessed 21st-century presentation and management of ASVI and focused on outcomes of combined arterial/venous injury. We reviewed the National Trauma Data Bank for patients with isolated arterial ASVI (group 1) and combined arterial/venous ASVI (group 2). Demographics, injury severity parameters, interventions, complications, and outcomes were compared. We identified 581 patients with ASVI (mean age 35.1; 88.1% male), with 466 isolated arterial injuries and 115 combined arterial/venous injuries. Group 2 had lower presenting systolic blood pressure and Glasgow Coma Scale, and had higher rates of operative repair (55.7 vs. 43.1%, p = 0.016) and higher mortality (33.9 vs. 13.9%, p < 0.001). There were no differences in amputation (5.2 vs. 2.4%, p = 0.121), compartment syndrome (2.6 vs. 1.9%, p = 0.713), and deep vein thrombosis (0.9 vs. 0.2%, p = 0.357). When separated by mechanism of injury, combined injuries from blunt trauma did increase amputation rates (27.8 vs. 4.2%, p = 0.002). Multivariate analysis revealed that combined arterial/venous injury significantly increased risk of death (odds ratio [OR], 2.99; confidence interval [CI], 1.73 to 5.17; p = 0.0001). Penetrating injury had higher odds of death than blunt injury (OR, 1.96; CI, 1.03 to 3.73; p = 0.041). ASVI is rare but extremely lethal. Concomitant venous and arterial injury is not associated with worse limb-related outcomes, except in blunt injuries and resultant amputations, but is associated with a threefold increase in mortality rates compared with isolated arterial injury.  相似文献   
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