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81.
Aortic stenosis (AS) and systemic atherosclerosis have been shown to be closely related. We evaluated the prevalence of aortic arch plaques and their possible association with the risk of cerebral infarction in patients with severe AS. Transesophageal echocardiography was performed in 116 patients with severe AS (55 men, mean age 71 ± 7 years, mean aortic valve area 0.68 ± 0.15 cm(2)) who were scheduled for aortic valve replacement. The presence, thickness, and morphology of the aortic arch plaques were evaluated using transesophageal echocardiography. Cerebral infarcts (chronic cerebral infarction and cerebral infarction after cardiac catheterization and aortic valve replacement) were assessed in all patients. Compared to age- and gender-matched control subjects, the patients with severe AS had a significantly greater prevalence of aortic arch plaques (74% vs 41%; p <0.0001) and complex arch plaques such as large plaques (≥4 mm), ulcerated plaques, or mobile plaques (30% vs 10%; p = 0.004). Multivariate logistic analyses showed that the presence of complex arch plaques was independently associated with cerebral infarction in patients with AS after adjusting for traditional atherosclerotic risk factors and coronary artery disease (odds ratio 8.46, 95% confidence interval 2.38 to 30.12; p = 0.001). In conclusion, the results from the present study showed that there is a greater prevalence of aortic arch plaques in patients with AS and that the presence of complex plaques is independently associated with cerebral infarction in these patients. Therefore, the identification of complex arch plaques using transesophageal echocardiography is important for risk stratification of cerebrovascular events in patients with severe AS.  相似文献   
82.
The purpose of this study was to test the efficacy of newly developed biplane transesophageal color Doppler and two-dimensional echocardiography in the evaluation of coronary artery anatomy and blood flow. Using these two techniques, high quality images of the entire main left coronary artery (from the left coronary ostium to the bifurcation of the left anterior descending and circumflex coronary arteries), adequate for assessment of luminal diameter and percent stenosis, were obtained in 34 (89%) out of 38 patients. Transesophageal color Doppler echocardiography visualized coronary blood flow in 32 (84%) of the 38 patients. Transesophageal two-dimensional echocardiography clearly showed significant (50% of greater) narrowing of the coronary lumen in 10 out of 12 patients (sensitivity; 83%) and insignificant narrowing or no abnormalities of the coronary lumen in 23 of 26 normal individuals (specificity; 88%). This preliminary study suggests that biplane transesophageal color Doppler and two-dimensional echocardiography are feasible, noninvasive techniques for imaging the main left coronary artery and blood flow.  相似文献   
83.
BACKGROUND: A newly developed automated mitral annular tracking method (AMAT) has recently become available and enables us to perform automated analysis of mitral annular dynamics. PURPOSE: To evaluate mitral annular dynamics using AMAT. METHODS: AMAT was performed using a Toshiba Aplio SSA-770 ultrasound system in 15 normal healthy volunteers (group N), 16 patients with anterior MI (group A), and 12 inferior MI (group B). The distance between an annular point at end-diastole and at end-systole (distance D) was automatically measured using AMAT at the basal portion of the anterior, lateral, posterior, inferior, and inferoseptal wall. The angle between the mitral annular plane at end-diastole and the direction of movement of each mitral annular point from end-diastole to end-systole (angle A) was also automatically measured at all five mitral annular points. The coefficients of variation (CV) of both distance D and of angle A were calculated as indices of asynchrony of mitral annular dynamics. RESULTS: CV of distance D in group A (22 +/- 9% (P < 0.01 vs group N)) and group B (22 +/- 10% (P < 0.01 vs group N)) were both significantly larger than in group N (13 +/- 4%). CV of angle A in group A (15 +/- 10% (P < 0.05 vs group N)) and group B (15 +/- 10% (P < 0.05 vs group N)) were also significantly larger than that in group N (8 +/- 3%). CONCLUSION: Automated analysis using AMAT showed that mitral annular dynamics of patients with MI were less symmetrical than in normal healthy volunteers.  相似文献   
84.
The automated contour tracking (ACT) method has been developed for the automated measurement of area volume using the energy minimization method without tracing a region of interest. The purpose of this study was to compare the ACT method and left ventriculography (LVG) for the measurement of left ventricular (LV) function in the clinical setting. An apical four-chamber view was visualized by two-dimensional echocardiography and recorded for off-line analysis in 14 patients with high-quality images who underwent LVG. The ACT method automatically traces the endocardial border from the recorded images and calculates LV volumes (end-diastole and end-systole) and ejection fraction (EF). Both ACT and LVG were compared by linear regression analysis for the measurement of EF. EF determined by the ACT method agreed well with that by LVG (r = 0.96, y = 0.94x + 4.6, standard error of the estimate = 3.9%). The mean difference between the ACT and LVG was -1.4%+/- 7.3%.In conclusion, the ACT method is reliable for noninvasive estimation of EF in high-quality images. This suggests that this new technique may be useful in the automated quantification of LV function.  相似文献   
85.
Abstract A case of sacral parasite is presented. A parasitic body with an incomplete lower limb was attached to the sacrococcygeal region of a female newborn at birth. The twins were easily separated by operation two days after birth. The parasite contained well developed small and/or large intestines, a multilocular cyst and a unilocular cyst. Histologically, the wall of the multilocular cyst consisted of tissues of three germ layers, such as central and peripheral nervous tissues, mature and immature intestine, pancreatic tissue, bronchial cysts, connective tissue, etc. The thick wall of the unilocular cyst consisted of central nervous tissue and connective tissue. The degree of differentiation of these tissues varied considerably. The parasite revealed no organ communication with the autosite. Since the operation, her growth and development have been favorable and no other abnormalities have been found.  相似文献   
86.
Recent development of an automated contour tracking (ACT) method using the energy minimization principle provides automated edge detection and tracking of the endocardial boundary of the left ventricle, without tracing a region of interest. This study determined whether left ventricular filling indexes obtained from the ACT method provide a reliable estimate of left ventricular diastolic filling. Fourteen patients were examined by the ACT method and equilibrium radionuclide ventriculography. The volume-time wave form for ACT measurements was obtained from the 4-chamber views. Peak filling rate and time to peak filling rate measured by the ACT method were compared with those determined by radionuclide ventriculography. Peak filling rate and time to peak filling rate by the ACT method were closely correlated with those determined by radionuclide ventriculography (peak filling rate: r = 0.88, y = 0.71x + 0.36, SEE = 0.54 ml/end-diastolic volume/sec, time to peak filling rate: r = 0.89, y = 0.72x + 30.0, SEE = 0.02 msec, respectively) The ACT method is useful for the assessment of left ventricular diastolic filling.  相似文献   
87.
In order to determine effects of iron deficiency on the living body, rats were given the iron deficient diet (Group 1, iron content, 0.32mg/100g), the complete diet added with iron (Group 5, iron content, 32.5mg/100g), the diet added with 1% chlorella (Group 2, iron content, 2.2mg/100g), the diet added with 5% chlorella (Group 3, iron content, 7.4mg/100g), or the diet added with 10% chlorella (Group 4, iron content, 13.9mg/100g). For the first 30 days, rats of all groups were given the iron deficiency diet to make them iron deficient, and were subsequently given the respective diet during the next 30 days to observe various changes in the conditions of rats. Following results were obtained. 1) When rats were reared for 30 days with the iron deficient diet, rats of these groups became anemic and their hemoglobin concentrations and hematocrit values lowered. Rats of Groups 3, 4 and 5 fed with the diets containing certain amounts of iron rapidly recovered, while the recovery of those of Group 2 fed with less iron content diet was delayed. Group 1 fed with the iron deficient diet showed no recovery. 2) Examination of effects of these diets on the rats body weight gains revealed that the growth of Groups 1 and 2 with iron deficiency was delayed notably (p less than 0.01) as compared with Group 5 and that of Group 3 was likewise restrained (p less than 0.05). The relative organ weights of all rats were examined. The liver weight in Groups 1, 2, 3, 4 was lower than that in Group 5, while that of the spleen in Groups 1 and 2 was higher than that in Group 5. 3) The Numbers of erythrocyte decreased in Groups 1 and 2 (p less than 0.01) and increased in Groups 3 and 4 (p less than 0.01) as compared with Group 5. There was no direct relation between the iron content in the diet and the number of leukocytes and their compositions. 4) Serum iron decreased remarkably in Groups 1 and 2 (p less than 0.01) but there were no intergroup differences in blood glucose value. 5) When osmotic fragility of erythrocyte membranes was expressed in term of NaCl concentration to indicate 50% hemolysis, Groups 1, 2 and 3 apparently increased their resistance as compared with Group 5 (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
88.
Increased oxidative stress is considered one of the main causes of steroid-induced osteonecrosis of the femoral head (ONFH). The aim of this study was to evaluate the effects of a steroid hormone and pentosan polysulfate sodium (pentosan), a heparin analog, in stroke-prone spontaneously hypertensive rats (SHRSP) as a model of ONFH. One hundred twenty-three 13-week-old male SHRSP/Izm rats were divided into four groups: a control group (group C), pentosan-administered group (group P), steroid-administered group (group S), and group administered pentosan plus steroid (group PS). Methylprednisolone acetate, as the steroid hormone, at a dose of 4 mg (15 mg/kg) was administered at 15 weeks of age. Pentosan at a dose of 3 mg/day/kg was continuously administered intraperitoneally from 13 weeks of age for 4 weeks. Rats were sacrificed at 17 weeks of age, and heart blood and both femora were collected. Triglyceride levels were significantly lower in group PS than in group S, indicating that pentosan improves lipid metabolism. The incidence of histologic ONFH was significantly lower in group P, at 14.8% (10/71 femoral heads), than in group C, at 30.4% (17/56 femoral heads), and significantly lower in group PS, at 40.8% (29/71 femoral heads), than in group S, at 91.3% (42/46 femoral heads), indicating that pentosan markedly inhibits ONFH. Immunohistochemical staining for oxidative stress showed that the stainability was significantly lower in group PS than in group S. Pentosan seems to reduce the incidence of ONFH in SHRSP by improving lipid metabolism and decreasing oxidative stress.  相似文献   
89.
To evaluate the pharmacokinetics of topical drugs, in vitro permeation studies are performed using sacrificed pig skin or human tissues resected at surgery; however, these methods have their limitations in in vivo pharmacokinetics. This study examined the usefulness of Mexican hairless pigs for in vivo pharmacokinetic study, especially the drug concentration in the tissues. A ketoprofen patch was applied on the back of Mexican hairless pigs for 24 h, followed by sequential collection of blood specimens from 0 to 36 h (n=3). Also, the skin, subcutaneous fat, fascia and muscle from the center of the site of application were excised at 12 h after the application (n=4). Ketoprofen was first detected in the plasma at 8 h, the concentration increasing up to 24 h; the plasma concentration began to decrease after the removal of the ketoprofen patch. Ketoprofen concentrations in the tissues decreased with increasing depth of the tissues, but the values in the deep muscles, being the lowest among the tissues examined, were still higher than those in the plasma. While the data of drug concentration in human tissue are difficult to test, the Mexican hairless pig model appears to be attractive for in vivo pharmacokinetic studies of topically applied ketoprofen. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
90.
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