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1.
In mammals, the indolealkylamine melatonin is synthesized mainly in the pineal gland and to a lesser degree in a number of extrapineal sites. To obtain more information on its distribution, melatonin was measured in the membranous cochlea of the guinea pig. Moreover, melatonin and other serotonin derivatives were determined in organ cultures after incubation with 14C-labelled serotonin. The results show that melatonin is detectable in the organ of Corti and the basilar membrane, and to a lesser degree also in the cochlear nerve and stria vascularis, including the spiral ligament. In vitro studies reveal the occurrence of a number of radiolabelled serotonin derivatives indicating that two of the melatonin-forming enzymes, serotonin N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT) are present in membranous cochlea. It is concluded that melatonin is synthesized in the guinea pig cochlea. Its role as modulator of hair cell function is dissolved. 相似文献
2.
Hypovitaminosis D (<30 ng/ml) is highly prevalent in allogeneic hematopoietic cell transplantation (alloHCT), but the relevance
of influencing factors for serum 25-hydroxyvitamin D3 [25(OH)D3] status in adult patients remains unknown. We are the first to have prospectively assessed 25(OH)D3 status and its influencing factors in 102 patients before and at days +30 and +100 after alloHCT. Among others, we evaluated
age, gender, weight, fat mass, season, sun exposure habits, and dietary and supplemental vitamin D intake as factors potentially
influencing baseline vitamin D status in uni- and multivariate linear regression analysis. Furthermore, we investigated the
impact of changes in fat mass, duration of parenteral nutrition, and acute graft-versus-host disease (aGVHD) on the course
of serum 25(OH)D3. Baseline 25(OH)D3 concentrations were 16.4 ± 8.9 ng/ml, revealing that the majority (89%) had concentrations beneath the normal range. In multivariate
linear regression model, only higher body fat mass remained an independent risk factor for reduced baseline 25(OH)D3 concentrations (P = 0.007). In the early post-transplant period, 25(OH)D3 status remained low, revealing a tendency to further deterioration, especially in patients with corticosteroid-treated aGVHD
(≥II). Reduced vitamin D status was very common in these patients before and after alloHCT, whereby the most important influencing
factors, namely season and dietary factors seem to have little impact. Our findings suggest that monitoring and if necessary,
correcting vitamin D status may be indicated at regular intervals before alloHCT and during long-term follow-up. Further investigations
of these patients' vitamin D requirements are needed, especially if they are on long-term corticosteroids. 相似文献
3.
Baumgartner C; Morell A; Hirt A; Bucher U; Forster HK; Doran JE; Matter L; Brun del Re G; Wagner HP 《Blood》1988,71(5):1211-1217
Elimination of neoplastic B cell populations from autologous bone marrow grafts also removes normal B lymphocytes. This is potentially hazardous for the reconstitution of the immune system in patients undergoing high-dose chemotherapy and total body irradiation followed by autologous marrow rescue. Five pediatric patients with B cell non- Hodgkin's lymphoma in first remission undergoing such a regimen were studied. They received bone marrow pretreated with anti-Y 29/55 monoclonal antibody and complement. B and T lymphocyte subpopulations reached normal levels within 6 months after autologous bone marrow transplantation (ABMT), and serum immunoglobulin levels became normal within 4 to 9 months. Vaccination with diphtheria and tetanus toxoid, trivalent poliomyelitis vaccine of the Salk type, and pneumococcal capsular antigens (38 to 54 months after transplantation) gave rise to specific antibody production. ABO isoagglutinins could be demonstrated in all patients. The response pattern was similar to that of patients who received unmanipulated autologous bone marrow. It is concluded that ex vivo anti-Y 29/55 depletion of the marrow graft does not induce relevant disturbances of humoral immune functions. 相似文献
4.
5.
Alzheimer’s disease(AD)is a neurodegenerative disease that is characterized by an age-dependent progressive decline of memory,impairment of cognitive functions and changes in personality and behavior.Despite the improvement in understanding of the mechanisms underlying the disease,AD remains an incurable complex disorder with multifaceted pathophysiology to date.Apolipoprotein E(ApoE)is the main cholesterol carrier in the brain that supports lipid transport between brain cells.The individuals carrying the APOE4 allele are known to be at increased risk of developing AD compared with those carrying the more common APOE3 allele. 相似文献
6.
Volz-Köster S Volz J Kiefer A Biesalski HK 《Journal of cancer research and clinical oncology》2000,126(1):53-56
PURPOSE: The appearance of the cervical mucosa is regulated by different factors including retinoic acid. Hormone-dependent alteration of the cervix uteri mucosa is accompanied by a decrease or increase of cytoplasmatic retinoic-acid-binding protein (CRABP). To elucidate whether this hormone-dependent alteration of CRABP is preserved in the case of neoplasms of the cervix uteri, we measured the level of total and apo-CRABP in normal and neoplastically transformed cervical cells. METHODS: In a prospective pilot study, standardised biopsies of normal epithelium and cervical intra-epithelial neoplasm grade 3 (CIN III) were taken from 24 patients. A newly developed method was used to determine the intra-epithelial level of apo- and total CRABP. RESULTS: The concentration of total CRABP in normal squamous epithelium compared with that in intra-epithelial neoplasm grade 3 is very significantly lower in the CIN III areas (normal: 3.66 +/- 1.46 pmol/ mg wet weight +/- SD; CIN III 1.43 +/- 0.59 pmol/mg P < 0.01). In addition CRABP in the apo form is lower in normal than in neoplastic epithelium (Wilcoxon test for paired non-parametric values: P < 0.05; mean for all patients: normal: 1.65 + 0.82 pmol/mg; CIN III: 1.14 +/- 0.23 pmol/mg). CONCLUSION: From our results we conclude that, in neoplastically transformed cells, the hormone-dependent CRABP cycle is interrupted. Whether this has consequences for the further development of the neoplastic cells has to be elucidated. 相似文献
7.
Biesalski HK 《European journal of clinical nutrition》2002,56(Z1):S2-11
Based on epidemiological studies it is assumed that meat, especially red meat, enhances risk for cancer, particularly of the colon, breast and prostate. Meat and meat products are important sources of protein, some micronutrients and fat. High fat intake has been blamed for correlation with different diseases, including cancer. Meat protein is reported to contribute to cancer formation. However, meat, including liver, is not only composed of fat and protein, it contains essential nutrients which appear exclusively in meat (vitamin A, vitamin B12) and micronutrients for which meat is the major source because of either high concentrations or better bioavailability (folate, selenium, zinc). In particular, vitamin A, folate and selenium are reported to be cancer-preventive, with respect to colon, breast and prostate cancer. Taken together, meat consists of a few, not clearly defined cancer-promoting and a lot of cancer-protecting factors. The latter can be optimized by a diet containing fruit and vegetables, which contain hundreds of more or less proven bioactive constituents, many of them showing antioxidative and anticarcinogenic effects in vitro. 相似文献
8.
We report in our present pilot study on the uptake of retinyl palmitate and its formation to retinol in buccal mucosal cells. Retinoids are able to change metaplastic lesions in several tissues. Prior to any clinical evaluation it is necessary to measure its uptake in target tissues such as the buccal mucosal epithelium. In this pilot study 12 volunteers creamed the inside of their cheeks lightly with a 0.1% retinyl palmitate containing toothpaste for 10 days followed by a wash out phase. On day 0, 3, 7, 10, 17 and 21, buccal mucosal cell samples were taken from volunteers and the uptake of retinol and retinyl palmitate was determined by HPLC analysis. An uptake of vitamin A was demonstrated in all volunteers. Comparing day 0 to day 3 a significant uptake of retinyl palmitate (p<0.05) was detected and comparing day 3 to 17 and 21 a significant decrease (p<0.05) during growth and differentiation of the mucosal epithelium could be seen. The subsequently formed retinol showed an increase but no statistical significance was determined. - The uptake of retinyl palmitate and the formation to retinol led to an enrichment of vitamin A in buccal mucosal cells. In this way metaplastic alterations of the buccal mucosal epithelium might be prevented or reversed by the application of topical retinyl palmitate. 相似文献
9.
Antibodies to tumor necrosis factor alpha prevent increases in cell replication in liver due to the potent peroxisome proliferator, WY- 14,643 总被引:7,自引:6,他引:7
Bojes HK; Germolec DR; Simeonova P; Bruccoleri A; Schoonhoven R; Luster MI; Thurman RG 《Carcinogenesis》1997,18(4):669-674
Several structurally dissimilar hypolipidemic drugs, plasticizers and
halogenated hydrocarbons induce peroxisomes in hepatocytes, and cause
hepatocellular adenoma and carcinoma in rats and mice. The mechanism by
which these agents act is unknown, although recent studies have suggested a
link between increased cell proliferation and hepatic cancer caused by
peroxisome proliferators. Here, we demonstrate that neutralizing antibodies
to tumor necrosis factor alpha (TNF alpha) block increases in protein
kinase C and cell proliferation due to [4-
chloro-6-(2,3-xylidino)-2-pyrimidinylthio]acetic acid (WY-14,643), a
hypolipidemic drug and potent peroxisome proliferator that causes tumors.
WY-14,643 moderately elevated the level of TNF alpha mRNA in the liver. TNF
alpha was detected immunohistochemically exclusively in Kupffer cells.
These results demonstrate that WY-14,643 acts as an indirect mitogen on
hepatocytes via TNF alpha. We propose that the Kupffer cell, a major source
of TNF alpha in the liver, is involved in the mechanism of the mitogenic
effect of WY-14,643.
相似文献
10.
J Komulainen R Lounamaa M Knip EA Kaprio HK Akerblom 《Archives of disease in childhood》1996,75(5):410-415
The determinants of the degree of metabolic decompensation at the diagnosis of type 1 (insulin dependent) diabetes mellitus (IDDM) and the possible role of diabetic ketoacidosis in the preservation and recovery of residual beta cell function were examined in 745 Finnish children and adolescents. Children younger than 2 years or older than 10 years of age were found to be more susceptible to diabetic ketoacidosis than children between 2 and 10 years of age (< 2 years: 53.3%; 2-10 years: 16.9%; > 10 years: 33.3%). Children from families with poor parental educational level had ketoacidosis more often than those from families with high parental educational level (24.4% v 16.9%). A serum C peptide concentration of 0.10 nmol/l or more was associated with a favourable metabolic situation. Low serum C peptide concentrations, high requirement of exogenous insulin, low prevalence of remission, and high glycated haemoglobin concentrations were observed during the follow up in the group of probands having diabetic ketoacidosis at the diagnosis of IDDM. Thus diabetic ketoacidosis at diagnosis is related to a decreased capacity for beta cell recovery after the clinical manifestation of IDDM in children. 相似文献