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991.
Localization of the genetic defect in multiple endocrine neoplasia type 1 within a small region of chromosome 11 总被引:18,自引:7,他引:11 下载免费PDF全文
Yusuke Nakamura Catharina Larsson Cecile Julier Camilla Bystrm Britt Skogseid Samuel Wells Kjell
berg Mary Carlson Thomas Taggart Peter O'Connell Mark Leppert Jean-Marc Lalouel Magnus Nordenskjld Ray White 《American journal of human genetics》1989,44(5):751-755
Multiple endocrine neoplasia type I (MEN-1), a Mendelian disorder with an autosomal dominant mode of inheritance, causes hyperplasia in the parathyroid glands and hyperplasia or neoplasm in the anterior pituitary gland and/or the pancreatic islets. The genetic defect responsible for MEN-1 in three families was recently mapped to the long arm of chromosome II by linkage between the MEN-1 locus and the gene for skeletal muscle glycogen phosphorylase (PYGM) at 11q13. We have constructed a genetic linkage map of seven markers in the vicinity of the MEN-1 locus that has allowed us to map more precisely the gene associated with MEN-1; the target region has been narrowed to about 12 cM. The closely linked markers will be useful also for identification of likely carriers in families in which an allele responsible for MEN-1 segregates. 相似文献
992.
The fungus Syncephalastrum racemosum (Cohn) Schroeter was found to transform the fungicide metalaxyl [N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-alanine methyl ester] in pure culture. After 21 days of incubation in a basal medium amended with 5 μg of metalaxyl per ml, more than 80% of the compound was transformed by the fungus. The transformation rates decreased as the concentrations of metalaxyl increased from 5 to 100 μg/ml. No transformation was observed when the concentration of metalaxyl was higher than 200 μg/ml. Two isomeric metabolites and a mixture of two other isomeric metabolites were isolated from the organic extract of the growth medium and identified as N-(2-methyl-6-hydroxymethylphenyl)-N- and N-(2-hydroxymethyl-6-methylphenyl)-N-(methoxyacetyl)-alanine methyl ester and N-(3-hydroxy- and N-(5-hydroxy-2,6-dimethyl-phenyl)-N-(methoxyacetyl)-alanine methyl ester according to their mass-spectral and nuclear magnetic resonance-spectral characteristics. Benzylic hydroxylation of the methyl side chains and/or aromatic hydroxylation appeared to be the major reactions involved in the metabolism of metalaxyl. 相似文献
993.
Marc Mesnil Jean-Marc Fraslin Colette Piccoli Hiroshi Yamasaki Christiane Guguen-Guillouzo 《Experimental cell research》1987,173(2):524-533
Specific differentiated gene expression and the morphology of adult rat hepatocytes can be maintained for as long as 8 weeks in vitro only when they are cultured in the presence of biliary epithelial cells; when primary hepatocytes are cultured alone, they lose these functions within 2 to 3 days. We obtained evidence suggesting that contact between hepatocytes and biliary epithelial cells is necessary for maintaining hepatocyte functions. We examined whether junctional communication between and among hepatocytes and biliary epithelial cells is required for long-term maintenance of hepatocyte functions, using a dye-transfer method, in three co-cultures: (1) hepatocytes and biliary epithelial cells prepared from Sprague-Dawley rats; (2) hepatocytes from Sprague-Dawley rats and epithelial cells of the IAR 20 line, originally established from BDVI rats; and (3) hepatocytes from BDVI rats and IAR 20 epithelial cells. The established epithelial cell line (IAR 20) and early-passage cultures of biliary epithelial cells maintained hepatocyte-specific functions in culture for 40 and 70 days, respectively, but the latter induced more stable maintenance of albumin secretion. Hepatocytes cultured alone lost their characteristic morphology within 5 to 8 days, and almost no dye transfer was observed. In co-cultures, the capacity of biliary epithelial cells to communicate among themselves remained relatively high throughout the culture period, whereas hepatocytes showed almost no junctional communication at an early phase of culture and first began to communicate after 2 weeks, communication capacity increasing for at least the next 10 days of culture. The most notable finding was that there was no dye transfer between hepatocytes and biliary epithelial cells in any co-culture system. These results suggest that the maintenance of hepatocyte-specific functions requires intercellular contact but probably not gap-junctional communication between hepatocytes and biliary epithelial cells. This system is useful for studying heterotypic cell-cell interactions and the control of gene expression. 相似文献
994.
Roland Bauchot Monique Diagne Jean-Marc Ridet Marie-Louise Bauchot 《Ichthyological Research》1989,36(2):260-266
Rhyacichthys aspro has one of the highest encephalization indices of the Gobioidei, at the level of the amphibiousPeriophthalmus (Gobiidae, Oxudercinae). This high encephalization can be explained by its adaptation to the turbulent waters of mountain torrents. The brain morphology is typical of a perciform fish and similar to that of a gobioid except in the form and size of the cerebellum. The quantitative analysis of the brain structures shows a large size of the olfactory centers, a small size of the visual centers (compared to those of other Gobioidei) and a very large size of the cerebellar centers (more than twice the size in other Gobioidei). The brain organization shows thatRhyacichthys aspro, although some of its brain structures are typically gobioid (tegmentum, medulla oblongata), is not a generalized gobioid, because of the high degree of its biological adaptation and the correlated large size of its cerebellum. 相似文献
995.
Andr Cabi Catherine Fitting Jean-Christophe Farkas Claude Laurian Jean-Michel Cormier Jean Carlet Jean-Marc Cavaillon 《Cytokine》1992,4(6):576-580
Surgery leads to significant modulation of the immune system, in which cytokines play a major role. Circulating interleukin 6 (IL-6) and IL-1 have been reported following surgery whereas tumor necrosis factor alpha (TNF-alpha) is only found in gut ischemia-associated surgery. We have investigated the consequences of surgery on in-vitro cytokine production by human monocytes stimulated by lipopolysaccharide (LPS) and staphylococcal toxic shock syndrome toxin-1 (TSST-1). Comparisons were made between the responsiveness of cells obtained the day before (D-1), during (D0) and after (D1, D2, D3) surgery. Patients undergoing abdominal aortic surgery (N = 9), carotid surgery (N = 4) and spinal surgery (N = 4) have been studied. A significant decrease of TNF-alpha, IL-1 beta and IL-1 alpha production by monocytes prepared from blood samples taken during the surgery was noticed, whereas IL-6 production was not significantly modified. On D2 a significant increase of monocyte responsiveness was observed and levels of cytokine productions rose back to initial values by the end of the follow up. The diminished in-vitro cytokine production observed during surgery might be the consequence of the effects of anaesthetic drugs, whereas the enhancement observed on D2 might reflect the surgical stress, leading to in-vivo priming of circulating monocytes. 相似文献
996.
997.
Plasmids in different strains of Streptomyces ambofaciens: free and integrated form of plasmid pSAM2
Jean-Luc Pernodet Jean-Marc Simonet Michel Guérineau 《Molecular & general genetics : MGG》1984,198(1):35-41
Summary Five strains of Streptomyces ambofaciens were examined for their plasmid content. Among these strains, four belong to the same lineage (strains B) and the other was isolated independently (strain A). A large plasmid (ca. 80 kb), called pSAM1 in this paper and already described, was present in all B strains, and absent in strain A. A second plasmid, not described before, was found as covalently closed circular DNA in two of the four B strains. This plasmid with a size 11.1 kb was called pSAM2. A restriction map for 14 enzymes was established. Hybridization experiments showed that a unique sequence homologous to this plasmid is integrated in a larger replicon, which is not pSAM1 and is probably the chromosome, in all B strains and not in strain A. It seems probable that the integrated se1uence is the origin of the free plasmid found in two strains of the B family. It is noteworthy that the integrated form and the free plasmid may be found together. Transformation experiments proved that pSAM2 may be maintained autonomously in S. ambofaciens strain A and in S. lividans. pSAM2 is a self-transmissible plasmid, able to elicit the lethal zygosis reaction. pSAM2 was compared to the plasmids SLP1, pIJ110 and pIJ408, which all come from integrated sequences in three Streptomyces species and are found as autonomous plasmids after transfer to S. lividans. If pSAM2 resembles these plasmids in its origin, it does not appear to be related directly to them. Concerning their plasmid content, the two isolates of S. ambofaciens are very different. One of them contains neither pSAM1 not pSAM2. As this isolate produces spiramycin, these plasmids probably do not play an important role in spiramycin production. Apart from its intrinsic biological interest, pSAM2 may be useful in the construction of cloning vectors for S. ambofaciens. Very stable transformants might be obtained in certain strains of S. ambofaciens, because of the possibility of integration of the pSAM2 derivative vector. 相似文献
998.
Judith Aron-Wisnewsky Eric O Verger Carine Bounaix Maria Carlota Dao Jean-Michel Oppert Jean-Luc Bouillot Jean-Marc Chevallier Karine Clément 《PloS one》2016,11(2)
Background
The number of morbidly obese patients undergoing bariatric surgery (BS) has increased dramatically in recent years. Therefore, monitoring food intake and its consequences in terms of nutritional status is necessary to prevent nutritional deficiencies. The aim of this study was to analyze the effect of food restriction on nutritional parameters in the short-term (≤3 months) period after BS in morbid obesity.Method
In a prospective study, we followed 22 obese women who underwent Roux-en-Y gastric bypass (GBP) or adjustable gastric banding (AGB) at baseline (T0) and 1 (T1) and 3 (T3) months after surgery. We evaluated food intake, nutrient adequacy and serum concentrations of vitamins and minerals known to be at risk for deficiency following BS.Results
Before surgery, we observed suboptimal food intakes, leading to a risk of micronutrient deficiencies. Serum analysis confirmed nutritional deficiencies for iron and thiamine for 27 and 23% of the patients, respectively. The drastic energy and food reduction seen in the short term led to very low probabilities of adequacy for nutrients equivalent across both surgeries. Serum analysis demonstrated a continuous decrease in prealbumin during the follow-up, indicating mild protein depletion in 21 and 57% of GBP patients and 50 and 63% of AGB patients, respectively, at T1 and T3. Regarding vitamins and minerals, systematic supplementation after GBP prevented most nutritional deficiencies. By contrast, AGB patients, for whom there is no systematic supplementation, developed such deficiencies.Conclusions
Our results suggest that cautious monitoring of protein intake after BS is mandatory. Furthermore, AGB patients might also benefit from systematic multivitamin and mineral supplementation at least in the short term. 相似文献999.
Jean-Marc Azaïs Jean-Luc Dortet-Bernadet 《Biometrical journal. Biometrische Zeitschrift》1999,41(7):873-890
This paper studies the modelling of linkage between chromosomes in tetraploids. A general model based on the assumptions of Kimber and Alonso (1981) is presented. It depends on the “elementary probabilities” associated with the different configurations of pairing of the four chromosome arms depending on the same quadruplet. Because of the incomplete information about these pairings given by the microscopic observation of the cells, some problems about the identifiability of the parameters arise. We will present a set of the most general parameters that are identifiable and we will describe the set of the elementary probabilities that correspond to these parameters. Finally, we shall discuss some various possible sub-models. 相似文献
1000.
Catherine Boucabeille Dominique Mengin-Lecreulx Gilles Henckes Jean-Marc Simonet Jean van Heijenoort 《FEMS microbiology letters》1997,153(2):295-301
Linenscin OC2 is an antibacterial substance produced by the orange cheese coryneform bacterium Brevibacterium linens OC2. It inhibits the growth of Gram-positive bacteria but it is inactive against Gram-negative bacteria. The intact outer membrane of Gram-negative bacteria was shown to be an effective permeability barrier against linenscin OC2. At high dosage the effect of linenscin OC2 was bacteriolytic on Listeria innocua. Bacteriostasis was observed at low dosage and peptidoglycan biosynthesis was affected at an early step upstream of the UDP-N-acetylglucosamine. Hemolytic activity of this substance on sheep erythrocytes suggested a common mode of action on prokaryotic and eukaryotic cells. It also suggested that the cytoplasmic membrane might be the primary target of linenscin OC2. 相似文献