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排序方式: 共有448条查询结果,搜索用时 0 毫秒
1.
Elizabeth Roberts Steven D Void Robert H Rosa David C Dries 《Ophthalmic surgery, lasers & imaging》2007,38(4):326-327
The presence of collateral vessels in a young child with glaucoma is rare. The authors describe a case of collateral vessel regression with intraocular pressure reduction in a child with primary congenital glaucoma. Six months following 180 degrees goniotomies in each eye, the intraocular pressure was reduced, dilation of the retinal arteries and veins resolved, and collateral vessels in both eyes regressed. Intraocular pressure reduction may lead to the regression of collateral vessels in children with primary congenital glaucoma. 相似文献
2.
M Mathru B Kleinman B Blakeman H Sullivan P Kumar D J Dries 《Critical care medicine》1992,20(10):1420-1425
OBJECTIVE: This study was designed to evaluate the oxygen transport adjustments and myocardial metabolic adaptation that occurs with different levels of hemodilution during normothermia after cardiopulmonary bypass. DESIGN: Prospective, nonrandomized study. SETTING: Operating room in a university hospital. PATIENTS: Eight patients with ejection fractions (> 40%) undergoing elective coronary artery bypass grafting. METHODS: Before the institution of cardiopulmonary bypass, blood was withdrawn from patients to a target hematocrit of 15%. After coronary artery bypass grafting, a catheter was inserted directly into the coronary sinus. After the patients were rewarmed to 37 degrees C, they were weaned from cardiopulmonary bypass. Hemodynamic indices were measured, as well as measurements of myocardial oxygen consumption (VO2) and myocardial metabolism (lactate extraction and coronary sinus hypoxanthine). Measurements were made at three different hematocrit values: 15%, 20%, and 25%. Hematocrit was increased by autologous blood transfusion. MEASUREMENTS AND MAIN RESULTS: The three levels of hemodilution (hematocrit: 17.4 +/- 3.4%; 23.0 +/- 3.7%; 27.8 +/- 4.8%) were significantly different from baseline (hematocrit 37 +/- 2.6%; p < .05). Oxygen delivery, which increased with autologous transfusion, exceeded 350 mL/min/m2 at each level of dilution. The myocardial VO2 increased significantly after autologous transfusion compared with the most dilute condition (7.0 +/- 3.7 mL/min at hematocrit 17.4% vs. 11.2 +/- 4.8 mL/min at hematocrit 23.0% and 12.4 +/- 4.0 mL/min at hematocrit 27.8%). This transfusion-induced increase was also true of myocardial oxygen extraction. Lactate extraction and hypoxanthine release were normal and unchanged at each level of hemodilution. Systemic oxygen extraction ratio increased with hemodilution and decreased with autologous transfusion. CONCLUSIONS: Hemodilution to a hematocrit of approximately 15% is tolerated in anesthetized humans after coronary artery bypass surgery. There was no evidence of myocardial ischemia, as demonstrated by absence of S-T depression on the electrocardiogram, lactate extraction, or hypoxanthine release. In selected patients, postoperative transfusion may be based on systemic physiologic end-points, such as oxygen extraction ratio, rather than set hematocrit values. 相似文献
3.
Lesser response to angiotensin-converting-enzyme inhibitor therapy in black as compared with white patients with left ventricular dysfunction 总被引:11,自引:0,他引:11
BACKGROUND: Black patients with heart failure have a poorer prognosis than white patients, a difference that has not been adequately explained. Whether racial differences in the response to drug treatment contribute to differences in outcome is unclear. To address this issue, we pooled and analyzed data from the Studies of Left Ventricular Dysfunction (SOLVD) prevention and treatment trials, two large, randomized trials comparing enalapril with placebo in patients with left ventricular dysfunction. METHODS: We used a matched-cohort design in which up to four white patients were matched with each black patient according to trial, treatment assignment, sex, left ventricular ejection fraction, and age. A total of 1196 white patients (580 from the prevention trial and 616 from the treatment trial) were matched with 800 black patients (404 from the prevention trial and 396 from the treatment trial). The average duration of follow-up was 35 months in the prevention trial and 33 months in the treatment trial. RESULTS: The black patients and the matched white patients had similar demographic and clinical characteristics, but the black patients had higher rates of death from any cause (12.2 vs. 9.7 per 100 person-years) and of hospitalization for heart failure (13.2 vs. 7.7 per 100 person-years). Despite similar doses of drug in the two groups, enalapril therapy, as compared with placebo, was associated with a 44 percent reduction (95 percent confidence interval, 27 to 57 percent) in the risk of hospitalization for heart failure among the white patients (P<0.001) but with no significant reduction among black patients (P=0.74). At one year, enalapril therapy was associated with significant reductions from base line in systolic blood pressure (by a mean [+/-SD] of 5.0+/-17.1 mm Hg) and diastolic blood pressure (3.6+/-10.6 mm Hg) among the white patients, but not among the black patients. No significant change in the risk of death was observed in association with enalapril therapy in either group. CONCLUSIONS: Enalapril therapy is associated with a significant reduction in the risk of hospitalization for heart failure among white patients with left ventricular dysfunction, but not among similar black patients. This finding underscores the need for additional research on the efficacy of therapies for heart failure in black patients. 相似文献
4.
Honl M Rentzsch R Schwieger K Carrero V Dierk O Dries S Louis H Pude F Bishop N Hille E Morlock M 《Bio-medical materials and engineering》2003,13(4):317-325
In revision surgeries of endoprostheses, the interface between implant and bone cement or bone must be loosened. Conventional tools have many disadvantages because of their size and limited range. Taking advantage of the selective and athermic cutting process, a plain water jet is already used in order to cut soft tissues. This study investigates the possibilities of both a plain and an abrasive water jet as cutting tools for revision surgery. Samples of the mid-diaphysis of human femora and bone cement (CMW3) were cut with a plain water jet (PWJ) and an abrasive water jet (AWJ) at two different jet-to-surface angles (30 degrees,90 degrees ) and at five different pressure levels (30, 40, 50, 60, 70 MPa). For a PWJ a selective pressure range was identified, where only bone cement was cut. Injecting a bio-compatible abrasive (lactose) to the jet stream resulted in significantly higher cut depths in both materials. Material removal in bone was significantly less at the smaller jet-to-surface angle for both techniques. No clear selectivity between bone and bone cement was observed for application of the AWJ. However, the material removal rate was significantly higher for bone cement than for bone at all pressure levels. The results indicate that an AWJ might be an alternative tool for cement removal. The possibility for localised cutting at interfaces could be an advantage for revision of a non-cemented prosthesis. 相似文献
5.
Temporal information in the responses of auditory neurons to sustained sounds has been studied mostly with periodic stimuli, using measures that are based on Fourier analysis. Less information is available on temporal aspects of responses to nonperiodic wideband sounds. We recorded responses to a reference Gaussian noise and its polarity-inverted version in the auditory nerve of barbiturate-anesthetized cats and used shuffled autocorrelograms (SACs) to quantify spike timing. Two metrics were extracted from the central peak of autocorrelograms: the peak-height and the width at halfheight. Temporal information related to stimulus fine-structure was isolated from that to envelope by subtracting or adding responses to the reference and inverted noise. Peak-height and halfwidth generally behaved as expected from the existing body of data on phase-locking to pure tones and sinusoidally amplitude-modulated tones but showed some surprises as well. Compared with synchronization to low-frequency tones, SACs reveal large differences in temporal behavior between the different classes of nerve fibers (based on spontaneous rate) as well as a strong dependence on characteristic frequency (CF) throughout the phase-locking range. SACs also reveal a larger temporal consistency (i.e., tendency to discharge at the same point in time on repeated presentation of the same stimulus) in the responses to the stochastic noise stimulus than in the responses to periodic tones. Responses at high CFs reflect envelope phase-locking and are consistent with previous reports using sinusoidal AM. We conclude that the combined use of broadband noise and SAC analysis allow a more general characterization of temporal behavior than periodic stimuli and Fourier analysis. 相似文献
6.
Bleyen L De Bacquer D Myny K Brochez L Naeyaert JM De Backer G 《International journal of epidemiology》1999,28(1):40-45
BACKGROUND AND METHODS: Changes over time of mortality rates from cutaneous malignant melanoma (CMM) in Belgium were analysed, based on people (n = 3695) aged 25-84 years, who died of CMM from 1954 to 1992. All data were collected from the Belgian National Institute of Statistics. For the log-linear analysis and calculation of the average annual change, only the data from 1973 to 1992 were considered. RESULTS: The age-adjusted mortality rates (per 10(5)) for the age group 25-84 years old increased from 0.5 in 1954 to 3.0 in 1992 in men, and from 0.8 in 1954 to 2.2 in 1992 in women. The average annual percentage change in men (-0.003%) was stable over the period 1973-1982, and increased to 4.4% over the period 1983-1992. In women, the average annual increase was 4.6% over the period 1973-1982, and continued to increase to 6.8% over the period 1983-1992. Log-linear analysis showed that the change in rates for both men and women was mainly due to an age-'drift' effect, contrary to the results of the average annual percentage change in men. CONCLUSION: The risk of dying from CMM increased in men and women continuously over the whole period, irrespective of birth cohort. In both men and women, there was approximately a 20% increase in CMM mortality per 5-year period. 相似文献
7.
To study optimal conditions of preparation of saphenous veins as coronary artery bypass grafts, segments of saphenous veins were obtained from 29 consecutive patients undergoing coronary artery bypass grafting. The saphenous vein segments were divided into three groups. In Group I, 10 saphenous vein segments were harvested using a "no-touch" technique without any other preparation aids. In Group II, 10 saphenous vein segments were removed while distended at 70-120 mm Hg with a balanced pH electrolyte solution at 37 degrees C. In Group III, consisting of 10 saphenous vein segments, nitroglycerin (1 microgram/ml) was added to the distending solution used in Group II. Samples of saphenous vein were assessed in a blind study using light and scanning electron microscopy to estimate endothelial cell preservation by the three harvest techniques. Saphenous veins receiving only a no-touch dissection technique without distention solution (Group I) revealed significantly better endothelial preservation (P less than 0.005). The administration of distention solution alone, or with nitroglycerin, to saphenous veins in situ using our operative technique during harvest does not appear to protect endothelial-integrity and may be harmful. 相似文献
8.
Chlorpromazine modulates cytokine expression in the liver and lung after burn injury and endotoxemia
Clancy KD Lorenz K Dries D Gamelli RL Hahn EL 《The Journal of trauma》2000,48(2):215-22; discussion 222-3
9.
Qualitative proof of liquid dispersion and penetration-involved granule formation in a high shear mixer. 总被引:1,自引:0,他引:1
Kaspar van den Dries Herman Vromans 《European journal of pharmaceutics and biopharmaceutics》2004,58(3):551-559
The origination of granules in the early seconds is an important aspect of high shear granulation. To elucidate these mechanisms, a substandard amount (1.5% w/w) of an aqueous hydroxypropyl cellulose solution was added to four different lactose mixtures: (1) lactose 100 M (d(4,3) approximately 170 microm), (2) lactose 200 M (d(4,3) approximately 50 microm), and (3, 4) 10% magnesium stearate/lactose 100 or 200 M. Between 1 and 15 s after binder addition samples were taken, which were immediately frozen in liquid nitrogen. The frozen sample was sieved into granular (> 280 microm) and non-granular-material (< 280 microm). The binder distribution in these fractions was determined. The observed binder distribution behaviour revealed that three different nucleation mechanisms can occur: (I) For lactose 100 M holds that all the binder is initially located in the granules. These granules are subsequently broken again. (II) The lactose 200 M granules also contain 100% of the added binder liquid. Contrary to lactose 100 M the lactose 200 M granules remain intact during the process. It is argued that in both cases liquid penetration is responsible for the accumulation of all liquid in the granules. A theoretical evaluation also confirmed that liquid penetration leads to the formation of the primary granules (III) No liquid penetration is possible in the hydrophobic magnesium stearate/lactose mixtures and the binder is completely dispersed in the non-granular material. 相似文献
10.
Christian Staufner Martin Lindner Carlo Dionisi-Vici Peter Freisinger Dries Dobbelaere Claire Douillard Nawal Makhseed Beate K. Straub Kimia Kahrizi Diana Ballhausen Giancarlo la Marca Stefan Kölker Dorothea Haas Georg F. Hoffmann Sarah C. Grünert Henk J. Blom 《Journal of inherited metabolic disease》2016,39(2):273-283