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91.
92.
A technique for simultaneous bilateral biplane arteriography of the abdomen, pelvis, and lower extremities is described. The biplane views provided clinically significant information in approximately 40% of cases.  相似文献   
93.
Bile was excluded from the gastrointestinal tract of 5 dogs with Heidenhain pouches by total external biliary fistulas. After a major portion of the jejunum and the ileum was resected Heidenhain pouch secretions increased in all instances. The results indicate that the increase in gastric secretion which regularly follows small-bowel resection is independent of the presence or absence of bile in the gastrointestinal tract.Supported by Grant AM-7750 from the US Public Health Service.The opinions expressed in this publication are those of the authors and not necessarily those of the US Air Force Medical Service.  相似文献   
94.
1. Numerical methods were used to simulate the voltage responses to an intrasomatic current step of neuronal models that incorporated tapering dendrites, dendrites of unequal electrotonic length, nonlinear membrane properties, and regional differences in specific membrane resistivity (Rm). A "peeling" technique was used to estimate the time constants (tau 0 and tau 1) and coefficients (a0 and a1) of the first two exponential terms of the series of exponential terms whose sum represented the slope of the voltage response. 2. The electrotonic structure of models with a uniform Rm was calculated using equations derived by Rall or Johnston or Brown et al. The adequacy of these methods were tested using a wide variety of models that conformed to the equivalent cylinder approximation of Rall. Johnston's method provided the most reliable estimate of electrotonic length (L) and the ratio of the dendritic conductance to the somatic conductance (rho). However, if L exceeded 2 and rho was eight or larger, the equations derived by Johnston could frequently not be solved due to small errors in the peeled values of tau 0, tau 1, a0, and a1. Although the method suggested by Brown et al. could be applied to all models, this method invariably underestimated L and rho. These errors were particularly large for model neurons with L values of 1.5 or larger and rho values of four or larger. Estimates of L using Rall's method were only reliable if rho was large and L was two or less. 3. Changing the geometry of the dendritic tree (dendritic tapering or dendrites of unequal L) or the addition of a time- and voltage-dependent conductance designed to mimic a sag process commonly seen in spinal motoneurons caused systematic changes in tau 0, tau 1, a0, and a1. The sag process always led to an underestimate of tau 0 even after applying a correction procedure. On the other hand, the ratio, tau 0/tau 1, was not affected by the sag process or dendritic tapering.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
95.
Ultrasound findings in hepatitis   总被引:1,自引:0,他引:1  
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96.
97.
The present article reports on the successful management of a large flail chest with traumatic pulmonary herniation in a patient who could not be weaned from mechanical ventilation following a course of conservative management. Surgical intervention involved open reduction and internal fixation with tubular plates to stabilize the flail segment, followed by a pectoralis major myocutaneous flap to repair the chest wall defect. Following surgical intervention, the patient was able to be weaned from mechanical ventilation and showed remarkable improvement in pulmonary function parameters. To the authors’ knowledge, the present report is the first to describe the use of open reduction and internal fixation of the chest wall and flap reconstruction to treat lung herniation with a flail chest segment.  相似文献   
98.

Background:

It is not known whether cardiovascular disease (CVD) risk level is related to knowledge of the leading cause of death of women or heart attack symptoms.

Hypothesis:

Women with higher CVD risk estimated by Framingham Risk Score (FRS) or metabolic syndrome (MS) have lower CVD knowledge.

Methods:

Women visiting primary care clinics completed a standardized behavioral risk questionnaire. Blood pressure, weight, height, waist size, fasting glucose, and lipid profile were assessed. Women were queried regarding CVD knowledge.

Results:

Participants (N = 823) were Hispanic women (46%), non‐Hispanic white (37%), and non‐Hispanic black (8%). FRS was determined in 278: low (63%), moderate (29%), and high (8%); 24% had ≥3 components of MS. The leading cause of death was answered correctly by 54%, heart attack symptoms by 67%. Knowledge was lowest among racial/ethnic minorities and those with less education (both P< 0.001). Increasing FRS was inversely associated with knowing the leading cause of death (low 72%, moderate 68%, high 45%, P = 0.045). After multivariable adjustment, moderate/high FRS was inversely associated with knowing symptoms (moderate odds ratio [OR] 0.52, 95% confidence interval [CI]: 0.28‐0.98; high OR 0.29, 95% CI: 0.11–0.81), but not the leading cause of death. MS was inversely associated with knowing the leading cause of death (P< 0.001) or heart attack symptoms (P = 0.018), but not after multivariable adjustment.

Conclusions:

Women with higher FRS were less likely to know heart attack symptoms. Efforts to target those at higher CVD risk must persist, or the most vulnerable may suffer disproportionately, not only because of risk factors but also inadequate knowledge. Clin. Cardiol. 2011 DOI: 10.1002/clc.22092 This work was supported in part by the US Department of Health and Human Services (1HHCWH05003‐01‐11); Arlene and Joseph Taub Foundation, Paterson, New Jersey; Edwina and Charles Adler Foundation; and by Columbia University's CTSA grant, UL1‐RR024156 from the NCRR/NIH. The authors have no other funding, financial relationships, or conflicts of interest to disclose.  相似文献   
99.
The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis is becoming an important part of glioblastoma classification. Besides the well-known cell cycle-related circuitries that are associated with glioblastoma onset and development, new insights may be derived by looking at pathways involved in regulation of epigenetic phenomena and cellular metabolism, which may both be highly deregulated in cancer cells. We evaluated if in glioblastoma patients the high grade of malignancy could be associated with aberrant expression of some genes involved in regulation of epigenetic phenomena and lipid metabolism. We measured the mRNA levels of ZFP57, TRIM28, CPT1A, CPT1B, and CPT1C in a cohort of 80 patients divided in two groups: grade II and grade IV. We evidenced that high grade glioblastoma is associated with increased level of ZFP57, a protein involved in gene imprinting, and aberrant expression of CPT1A and CPT1C, regulators of fatty acid oxidation. Our study may pave the way to identify new markers that could be potentially useful for diagnosis and/or prognosis of glioblastoma.  相似文献   
100.
Rationale, aims and objectives Drug‐eluting coronary stents (DES) rapidly dominated the marketplace in the United States after approval in 2003, but utilization rates were initially lower among African American patients. We assess whether racial differences persisted as DES diffused into practice. Methods Medicare claims data were used to identify coronary stenting procedures among elderly patients with acute coronary syndromes (ACS). Regression models of the choice of DES versus bare mental stent controlled for demographics, ACS type, co‐morbidities and hospital characteristics. Diffusion was assessed in the short run (2003–2004) and long run (2007), with the effect of race calculated to allow for time‐varying effects. Results The sample included 381 887 Medicare beneficiaries treated with stent insertion; approximately 5% were African American. Initially (May 2003–February 2004), African American race was associated with lower DES use compared to other races (44.3% versus 46.5%, P < 0.01). Once DES usage was high in all patients (March–December 2004), differences were not significant (79.8% versus 80.3%, P = 0.45). Subsequent concerns regarding DES safety caused reductions in DES use, with African Americans having lower use than other racial groups in 2007 (63.1% versus 65.2%, P < 0.01). Conclusions Racial disparities in DES use initially disappeared during a period of rapid diffusion and high usage rates; the reappearance of disparities in use by 2007 may reflect DES use tailored to unmeasured aspects of case mix and socio‐economic status. Further work is needed to understand whether underlying differences in race reflect decisions regarding treatment appropriateness.  相似文献   
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