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41.
Autoimmune thrombocytopenic purpura is estimated to be one of the most common acquired bleeding disorders of children. The pathogenesis involves the generation of autoantibodies against the normally expressed glycoproteins on the platelet membranes. These antibody-coated platelets in turn are destroyed by the spleen and other reticuloendothelial organs. Although the disease can occur without an identifiable etiology, many underlying pathologies, including infections, can be found. We report the mumps virus as a rare etiology of secondary autoimmune thrombocytopenic purpura. 相似文献
42.
OBJECTIVES/HYPOTHESIS: Recent studies have established a strong relationship between the development of myringosclerosis and reactive oxygen species (ROS). The aims of the present study were to directly detect ROS in the tympanic membrane and middle ear mucosa of rats by measuring luminol amplified chemiluminescence, to evaluate the changes in the levels of ROS after treatment with vitamin E, and to examine the possible changes in the tympanic membranes otomicroscopically and histologically. STUDY DESIGN: Prospective controlled animal study. METHODS: Forty healthy Sprague-Dawley rats were divided into five groups of eight animals each. Animals in all groups except group 1 were bilaterally myringotomized. Group 2 received no treatment, group 3 was treated with topical olive oil, group 4 received topical vitamin E, and group 5 received intramuscular vitamin E. After 24 hours of myringotomy, tympanic membranes were examined otomicroscopically; thereafter, tympanic membranes and middle ear mucosa were peeled off. The right ears of the animals were used for biochemical assay, and the left ears were used for histological study. RESULTS: Reactive oxygen species levels were significantly decreased in group 4 with topical application of vitamin E compared with untreated and myringotomized animals in group 2. Reactive oxygen species levels were also decreased in group 5, although the decrease was not statistically significant when compared with groups 2 and 3. Histological studies confirmed sclerotic changes in the untreated myringotomized animals. The tympanic membranes of animals in groups 2 and 3 showed a white, chalk-like pattern of sclerotic changes, whereas animals in groups 4 and 5, with the exception of two animals in group 5, lacked these changes. CONCLUSION: Although the relationship between the development of myringosclerosis and ROS had been well documented previously, the present study is the first that has directly measured the levels of ROS in the tympanic membrane and middle ear mucosa. These results are relevant because they correlate with histological findings. It has also been demonstrated that topically applied vitamin E is effective in decreasing the ROS levels. 相似文献
43.
Oxidative stress and antioxidant status in elderly diabetes mellitus and glucose intolerance patients 总被引:5,自引:0,他引:5
Atli T Keven K Avci A Kutlay S Turkcapar N Varli M Aras S Ertug E Canbolat O 《Archives of gerontology and geriatrics》2004,39(3):269-275
Increased oxidative stress and impaired anti-oxidant defense have been suggested as contributory factors for initiation and progression of complications in diabetes mellitus. Aging itself has been shown to be along with increased oxidative stress and lower anti-oxidant defense. We aimed at investigating oxidative stress and anti-oxidant enzymes in 61 elderly subjects. Fifteen healthy individuals (group 1, mean age 72.2 +/- 5.13), 13 glucose intolerant patients (group 2, mean age 71.7 +/- 4.9), 19 patients with type 2 diabetes mellitus (T2DM) without any complication (group 3, mean age 70.0 +/- 6.0), and 14 patients with T2DM with at least one complication (group 4, mean age 69.8 +/- 4.7) were included in the study. Whilst plasma levels for malondialdehyde (MDAP) and erythrocyte malondialdehyde (MDAE) were measured as markers of oxidative stress, activity of erythrocyte superoxide dismutase (SOD), glutathion peroxidase (GSH-Px), and catalase (CAT) were taken as markers of oxidative defense system. MDAP level was significantly elevated in group 4 (P = 0.001). MDAE was elevated in patients with T2DM, particularly in group 4, however, the difference between the groups was of borderline significance (P = 0.07). Whilst CAT was elevated in groups 3 and 4 compared to control subjects (P = 0.025 and 0.002, respectively), no difference was found for SOD between the groups. GSH-Px activity was found to be increased in groups 2, 3 and 4, it did not reach statistical significance (P = 0.106). There were significant correlations between CAT and MDAE (P < 0.0001, r = 0.056) and MDAP (P = 0.016, r = 0.306). These results suggest that there was an increased oxidative stress in elderly diabetics, however, this is not due to reduced erythrocyte antioxidant defense potential but, rather, increased free radical production possibly due to hyperglycemia. 相似文献
44.
Hypercoagulability risk factors in children with minimal change disease and the protective role of protein-C activity 总被引:2,自引:0,他引:2
It is believed that thrombotic activity in nephrotic syndrome is due to an imbalance between procoagulant/thrombotic and anticoagulant/antithrombotic factors in plasma. The aim of this study was to investigate the hypercoagulability risk in childhood minimal change disease and to find possible protective mechanisms with respect to hemostasis. Twenty-six children with minimal change disease were enrolled in this study. All patients were evaluated during an attack and on remission. The control group consisted of 33 healthy children. During the attack period, prothrombosis parameters, total lipid, cholesterol, fibrinogen levels and platelet count increased significantly compared to levels in the remission period. This denotes that hyperviscosity increases thrombosis tendency. In the attack period, the significant increase of prothrombin fragments 1+2 which shows thrombin formation and thrombin-antithrombin complex which causes prothrombin activation, are an indication of increased thrombosis risk. Five patients with lupus anticoagulant present and 7 patients with activated protein-C resistance ratios carried an increased thrombosis risk. D-dimer level of fibrinolytic factors significantly increased during the attack period. These findings emphasize the existence of thrombotic activity causing the activation of the fibrinolytic system. The significant increase in protein-C activity in these patients represents one of the protective mechanisms against thrombosis. The decrease in tissue plasminogen activator and antiplasmin indicates the protective role of fibrinolytic activity. Consequently, an increase in the protein-C activity is one of the protective mechanisms. The fibrinolytic system also plays an important role in preventing thrombotic activity in these patients. 相似文献
45.
Erdoğan MF Küçük NO Anil C Aras S Ozer D Aras G Kamel N 《Nuclear medicine communications》2004,25(11):1083-1087
BACKGROUND: Autonomously functioning toxic adenomas are a common cause of hyperthyroidism. Although 131I seems to be a good therapeutic option with little postablative hypothyroidism for these patients, only a small number of recent studies have objectively evaluated changes in nodule size by ultrasonography following radioiodine therapy. METHODS: We prospectively followed 39 patients with a mean age of 51.2 (35-75) years for 12 months and the patients who remained toxic thereafter, until euthyroidism was provided. Thyroid function tests, sonographic volumes were determined initially and 3, 6 and 12 months after treatment. Radioiodine doses of 3.7 MBq.g(-1) thyroid tissue corrected to a 100% 24 h 131I uptake were given. Thirty patients received a single dose, two required two doses and three required three to five doses of 131I due to persistent thyrotoxicosis. Sonographic volumes of the diffuse parts of the glands decreased significantly by 18% from a mean+/-SD value of 50+/-27.6 ml to 41+/-27.4 ml by the end of the 12 months. A significant decrease (8.3%, P=0.002) was achieved in the first three months. Toxic adenomas decreased in size more efficiently (54%) from a mean of 26+/-24 ml to 12+/-10 ml during 12 months, but also most significantly (28.8%, P=0.003) in the first 3 months of the follow-up. Thirty of the patients (76.9%) became euthyroid at the end of 12 months of follow-up. Four patients (10.3%) became overtly hypothyroid during the follow-up. CONCLUSION: Single or multiple doses of radioiodine can successfully treat toxic adenomas with a low rate of hypothyroidism and considerable nodule-volume reduction. 相似文献
46.
Coleman PJ Brashear KM Askew BC Hutchinson JH McVean CA Duong le T Feuston BP Fernandez-Metzler C Gentile MA Hartman GD Kimmel DB Leu CT Lipfert L Merkle K Pennypacker B Prueksaritanont T Rodan GA Wesolowski GA Rodan SB Duggan ME 《Journal of medicinal chemistry》2004,47(20):4829-4837
3-(S)-Pyrimidin-5-yl-9-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-nonanoic acid (5e) and 3-(S)-(methylpyrimidin-5-yl)-9-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-nonanoic acid (5f) were identified as potent and selective antagonists of the alpha(v)beta(3) receptor. These compounds have excellent in vitro profiles (IC(50) = 0.07 and 0.08 nM, respectively), significant unbound fractions in human plasma (6 and 4%), and good pharmacokinetics in rat, dog, and rhesus monkey. On the basis of the efficacy shown in an in vivo model of bone turnover following once-daily oral administration, these two compounds were selected for clinical development for the treatment of osteoporosis. 相似文献
47.
Aral SO 《AIDS alert》2004,19(12):140-141
Q & A with Sevgi O. Aral, from the Division of STD Prevention with the CDC. 相似文献
48.
Ozdemir M Bakaris S Ozdemir G Buyukbese MA Cetinkaya A 《Canadian journal of ophthalmology. Journal canadien d'ophtalmologie》2004,39(5):526-532
BACKGROUND: Ocular surface changes, mainly squamous metaplasia of the conjunctival epithelium and corneoconjunctival calcification of unknown etiology, may develop in patients with chronic renal failure undergoing hemodialysis. An association between squamous metaplasia and corneoconjunctival calcification has been suggested. The purpose of this study was to investigate the relation between ocular surface disorders and tear function changes in patients with chronic renal failure undergoing hemodialysis. METHODS: In this prospective case-control study, 42 patients with chronic renal failure and 20 age- and sex-matched control subjects underwent full ophthalmologic examination, tear function tests (including Schirmer's test, tear film break-up time [BUT] test and rose bengal staining) and impression cytology to determine the degree of conjunctival squamous metaplasia. They also responded to a questionnaire regarding subjective ocular complaints. Corneoconjunctival calcification was graded on a scale of 0 to 5 according to the system proposed by Porter and Crombie. Impression cytology samples were graded on scale of 0 to 3 according to the Nelson classification. The relation between ocular surface disorders and tear function changes was evaluated. RESULTS: Of the 42 patients, 12 (28%) had grade 0 calcification, 10 (24%) had grade 1, 14 (33%) had grade 2, and 6 (14%) had grade 3 or higher. Four patients (10%) had grade 0 squamous metaplasia, 22 (52%) had grade 1, 12 (28%) had grade 2, and 4 (10%) had grade 3. The difference between the patient and control subjects in squamous metaplasia grades and corneoconjunctival calcification grades was statistically significant (p < 0.001 and p = 0.022 respectively). Abnormal tear film BUT (p = 0.002) and abnormal rose bengal staining (p = 0.023) were significantly more frequent in the patient group than in the control group. The grade of conjunctival squamous metaplasia was correlated with abnormal rose bengal staining (tau = 0.79, p < 0.001) and with the existence of subjective ocular complaints (tau = 0.32, p = 0.026). There was no correlation between corneoconjunctival calcification and tear function changes. INTERPRETATION: Abnormal rose bengal staining and the presence of subjective ocular complaints may be used as follow-up criteria for ocular surface disorders in patients with chronic renal failure regularly undergoing hemodialysis. 相似文献
49.
We observed less severe symptoms in patients with chronic idiopathic thrombocytopenic purpura (ITP) than in patients with acute ITP with similar platelet counts. Thrombopoietin (TPO), soluble P-selectin, soluble P-selectin per platelet, and interleukin 6 (IL-6) were evaluated in children with ITP before treatment in 16 acute and 22 chronic cases and after treatment in 10 acute and chronic cases who received mega-dose methylprednisolone. The levels of IL-6, soluble P-selectin, soluble P-selectin per platelet, and platelet count were similar in acute and chronic ITP (P > 0.05) but TPO in acute ITP was higher than that of the patients with chronic ITP (P < 0.05). The posttreatment IL-6 and TPO declined (P < 0.05), but soluble P-selectin and platelet count increased (P < 0.05). Posttreatment soluble P-selectin per platelet levels were higher than the normal values (P < 0.05). These results suggest that IL-6, soluble P-selectin, and soluble P-selectin per platelet are not responsible for the milder symptoms in chronic than in acute ITP. Mega-dose methylprednisolone seems to keep the soluble P-selectin levels elevated. 相似文献
50.