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排序方式: 共有671条查询结果,搜索用时 15 毫秒
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SP Attard-Montalto C Camacho-Hübner AM Cotterill L D'Souza-Li S Daley K Bartlett D Halliday OB Eden 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(1):54-60
Changes in insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding proteins (IGFBPs) were correlated with protein synthesis and breakdown using [1- 13C]leucine before chemotherapy and during subsequent febrile neutropenia (FN) in eight children with cancer, aged 6.3–17.5 y. IGF-I levels were similar to age-matched controls before chemotherapy (mean ±SEM: 250 ±28 and 228 ±22 μg l-1, respectively). During FN, IGF-I fell to 156 ±22 /ng l -1(p= 0:02), and rose to 276 ±27 μ g l -1 with recovery at 6 months (p = 0:004). Similarly, IGFBP-3 decreased from 4.0 ±0.2mgl-1 before chemotherapy to 3.0 ±0.3 mgl-1 during FN (p= 0:01), and returned to 4.1 ±0.2mgl -1 at 6 months (p= 0:01). IGF-I correlated with IGFBP-3 (r=+0:7, p <0:001). Scanning densitometry showed a decrease in IGFBP-3 from 94 to 54% during FN, when the presence of IGFBP-3 protease activity was observed. Compared with normal human serum, IGFBP-2 was elevated throughout the study. IGFBP-1 increased from 14.6 ±3.5 to 30.6 ±2.8/ngl-1 (p = 0:004), whereas serum insulin decreased from 26.5 ±6.8 to 7.8 ±0.8 mUl-1 (p= 0:03) before and during FN, respectively. Whilst IGF-I and IGFBP-3 fell, daytime growth hormone increased from 3.3 ±0.6 to 6.7±0.8mUl -1 (p= 0:01), and cortisol from 197 ±48 to 594±98nmoll -1 (p = 0:005). Albumin decreased from 47 ±2 to 38 ±2gl-1 (p= 0:004) and improved to 47 ±2gl-1 with recovery (p= 0:003). Protein synthesis increased from 4.5 ±0.4 to 5.0 ±0.6gkg-1 d-1 before chemotherapy and during FN, while protein breakdown rose from 5.4 ±0.4 to 6.3 ±0.4kg-1d-1. Increasing protein breakdown was related to falling IGF-I and IGFBP-3 levels. Modification of IGFBP-3 by circulating proteolytic activity may alter IGF bioavailability, allowing protein synthesis to increase during periods of severe catabolic stress. 相似文献
74.
Objective: To identify risk factors for development of dehydration in under five year olds with acute watery diarrhoea.Design: Hospital based unmatched case-control study.Setting: Diarrhoea Treatment Unit, Government Medical College Hospital, Nagpur, India.Participants: The study included 387 cases of diarrhoea having severe or moderate dehydration and 387 controls suffering from diarrhoea with mild or no dehydration.Risk factors: The study included infancy, female sex, religion, residing in urban slums or rural area, under nutrition, cessation of breast feeding during diarrhoeal episode, fluid intake decreased/stopped during diarrhoea, ORS not received, home available fluids (HAF) not received, both ORS and HAF not received, non-washing of hands by mother before preparation of food, after defaecation, after disposal of faeces, history of measles in the previous six months, frequency of stools >8/d, frequency of vomiting more than twice per day and temperature more than 99°F, as risk factors for development of dehydration.Statistical analysis: Univariate analysis included OR, 95% CI for OR and Chi-square test. Multivariate analysis was carried out by unconditional multiple logistic regression (MLR).Results: This study identified the significance of infancy, religion, severe undernutrition, non-washing of hands by mother before preparation of food, frequency of stool >8/d, frequency of vomiting >2/d, history of measles in previous six months, withdrawal of breast feeding during diarrhoea, withdrawal of fluids during diarrhoea and not giving ORS, HAF or both during diarrhoea, in the outcome of development of moderate or severe dehydration.Conclusions: Timely intervention in the preventable risk factors included in this study may prevent the development of moderate or severe dehydration in the children suffering form acute watery diarrhoea. 相似文献
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SP Cannavò† F Borgia† M Vaccaro† F Guarneri† E Magliolo‡ B Guarneri† 《Journal of the European Academy of Dermatology and Venereology》2002,16(6):625-627
Pretibial myxoedema is a cutaneous mucinosis typically associated with Graves' disease, although it may also develop in subjects with non-thyrotoxic thyroid pathologies. This report presents a rare case of pretibial myxoedema occurring in a 58-year-old woman with biopsy-proven Hashimoto's thyroiditis. The hypothetical pathogenetic link between the two disorders is discussed with particular attention to the role of thyroid stimulating hormone receptor antibodies. 相似文献
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79.
Double-labeled immunofluorescence study of cutaneous nerves in psoriasis 总被引:14,自引:0,他引:14
Wen-Yue Jiang MD Siba P. Raychaudhuri MD Eugene M. Farber MD 《International journal of dermatology》1998,37(8):572-574
Background and objective In recent years, many reports have suggested an active role of neuropeptides in the pathogenesis of psoriasis. Increased numbers of neuropeptide-containing nerves positive for substance P (SP), vasoactive intestinal polypeptide (VIP), and calcium gene-related peptide (CGRP) have been reported in psoriatic tissue. As psoriatic epidermis has a larger mass/volume, however, it is expected to have more nerves and a higher number of neuropeptergic fibers. Therefore, instead of demonstrating a larger number of neuropeptergic fibers, a more significant study is to investigate whether the neuropeptergic fibers are denser in psoriatic tissue. In this study, we applied a double labeled immunofluorescence technique. This method allows the identification of the total number of nerve fibers and the number of nerves positive for specific neuropeptides. Materials and methods We obtained biopsies from nine lesional and seven non-lesional psoriatic skins and six normal controls. Biopsies were snap frozen and then cut into 14 μm cryosections. The tissues were first treated with anti-microtubule associated protein (MAP)2 antibody to stain the nerves. This was followed by a second set of stainings for SP, VIP, and CGRP. Primary antibodies were used in dilutions of 1 : 200 for anti-MAP2, 1 : 200 for anti-SP, 1 : 800 for anti-VIP, and 1 : 400 for anti-CGRP. Results We found that the percentage of SP-positive fibers was twofold greater and the percentage of CGRP-positive fibers was 2.5 times greater in the psoriatic epidermis than in the epidermis of normal skin. Psoriatic epidermis had 30.1 ± 3.9% SP-positive nerve fibers compared with 15.7 ± 3.7% in the normal control. The corresponding values for CGRP-positive nerve fibers were 30.1 ± 3.9% and 12.0 ± 4.2%. Conclusions The results of our study suggest that SP- and CGRP-containing neuropeptide nerve fibers are more dense in the psoriatic epidermis. Both SP and CGRP are chemotactic to neutrophils and mitogenic to keratinocytes and endothelial cells. In addition, SP activates T lymphocytes and induces adhesion molecules on the endothelial cells. Our observations suggest that neuropeptides may play a significant role in the inflammatory and proliferative process of psoriasis. 相似文献
80.
Inhibition of tissue factor/factor VIIa activity in plasma requires factor X and an additional plasma component 总被引:10,自引:0,他引:10
A study was carried out to explore requirements for the inhibition of tissue factor-factor VIIa enzymatic activity in plasma. Reaction mixtures contained plasma, 3H-factor IX or 3H-factor X, tissue factor (vol/vol 2.4% to 24%), and calcium. Tissue factor-factor VIIa activity was evaluated from progress curves of activation of factor IX or factor X, plotted from tritiated activation peptide release data. With normal plasma, progress curves exhibited initial limited activation followed by a plateau indicative of loss of tissue factor-factor VIIa activity. With hereditary factor X-deficient plasma treated with factor X antibodies, progress curves revealed full factor IX activation. Adding only 0.4 micrograms/mL factor X (final concentration) could restore inhibition. Inhibition was not observed in purified systems containing 6% to 24% tissue factor, factor VII, 0.5 micrograms/mL, factor IX, 13 micrograms/mL, and factor X up to 0.8 micrograms/mL, but could be induced by adding barium-absorbed plasma to the reaction mixture. Thus, both factor X and an additional material in plasma were required for inhibition. The amount of factor X needed appeared related to the concentration of tissue factor; adding more tissue factor at the plateau of a progress curve induced further activation. These results also indicate that inhibited reaction mixtures contained active free factor VII(a). Preliminary data suggest that inhibition may stem from loss of activity of the tissue factor component of the tissue factor- factor VII(a) complex. 相似文献