全文获取类型
收费全文 | 389篇 |
免费 | 62篇 |
专业分类
451篇 |
出版年
2021年 | 4篇 |
2020年 | 3篇 |
2016年 | 7篇 |
2015年 | 13篇 |
2014年 | 10篇 |
2013年 | 11篇 |
2012年 | 12篇 |
2011年 | 16篇 |
2010年 | 6篇 |
2009年 | 13篇 |
2008年 | 11篇 |
2007年 | 14篇 |
2006年 | 6篇 |
2005年 | 9篇 |
2004年 | 8篇 |
2003年 | 15篇 |
2002年 | 15篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 7篇 |
1991年 | 12篇 |
1990年 | 11篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 11篇 |
1982年 | 5篇 |
1981年 | 15篇 |
1980年 | 10篇 |
1979年 | 14篇 |
1978年 | 10篇 |
1977年 | 7篇 |
1976年 | 14篇 |
1975年 | 9篇 |
1974年 | 14篇 |
1973年 | 6篇 |
1972年 | 6篇 |
1971年 | 10篇 |
1962年 | 2篇 |
1958年 | 3篇 |
1957年 | 2篇 |
排序方式: 共有451条查询结果,搜索用时 15 毫秒
1.
2.
Gershon Shafir 《Ethnic and racial studies》2013,36(2):172-197
This study questions the customary thesis according to which the dominant status of the ashkenazim (European Jews) over the mizrachim (Middle Eastern and North African Jews) in Israeli society is to be explained by the earlier arrival of the former in Palestine. It does so by demonstrating that an early wave of Yemenite Jews, who arrived in Palestine simultaneously with the founding fathers, remained in a subservient social position. Archival sources, memoirs, and contemporary newspapers are used to explain the low status of Yemenite Jews by reference to the broader context of the Jewish‐Arab conflict as it took shape in Palestine's labour and land markets. 相似文献
3.
Experiments were done to test the hypothesis that the avian gut is colonized by cells derived from both vagal and sacral regions of the neural crest. A fluorescent dye, diI (1,1-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate), and a replication-deficient retrovirus (LZ10; Galileo et al. 1990) were employed as tracers. Since LZ10 was constructed with lacZ of E. coli as a reporter gene, infected cells were identified by demonstrating beta-galactosidase immunoreactivity. DiI and LZ10 were injected between the neural tube and surface ectoderm (before the migration of crest cells away from the injection sites) at vagal, truncal (diI only), or sacral axial levels. The bowel was examined 4 days later in order to allow crest-derived cells sufficient time to migrate to the gut. Following injections of either tracer into the vagal crest, labelled cells were found in the gizzard and duodenum. When diI or LZ10 was injected into the sacral crest, labelled cells were seen in the post-umbilical bowel and ganglion of Remak. In the hindgut, marked cells were concentrated in the mesenchyme, just internal to the serosa, and were never observed rostral to the umbilicus. No fluorescent cells were ever found in the bowel following truncal injections of diI, although such cells were observed in sympathetic ganglia. Labelled cells were always found in dorsal root ganglia, no matter which tracer or level of the crest was injected. In embryos injected with LZ10, infected cells in the gut and dorsal root ganglia displayed a neural crest marker (NC-1 immunoreactivity). These observations confirm that the gut is colonized by cells from the sacral as well as the vagal region of the neural crest and that the emigrés from the sacral crest are confined to the post-umbilical bowel. 相似文献
4.
Adrenal chromaffin granules and secretory granules from thyroid parafollicular cells have several common antigens 总被引:3,自引:0,他引:3
The presence of various antigens in two types of isolated endocrine vesicles (chromaffin granules and secretory vesicles of thyroid parafollicular cells) was investigated by immunoblotting. The two types of vesicles have three common secretory proteins: chromogranin A, chromogranin B and secretogranin II. Furthermore, six common membrane antigens were found: cytochrome b-561, carboxypeptidase H, glycoprotein II, glycoprotein III, synaptin/synaptophysin and SV 2. These results demonstrate that vesicles obtained from neural crest-derived endocrine cells not only share several common secretory peptides and proteins, but also have common properties as far as their membrane antigens are concerned. 相似文献
5.
Manic depressive illness not linked to factor IX region in an independent series of pedigrees 总被引:1,自引:0,他引:1
P V Gejman S Detera-Wadleigh M M Martinez W H Berrettini L R Goldin J Gelernter W T Hsieh E S Gershon 《Genomics》1990,8(4):648-655
We studied seven informative kindreds segregating for manic depressive illness (MDI), consistent with X-chromosome transmission of the trait (families do not show affective disease in both a father and a son), using markers mapped to the region of Xq27-Xq28. The lod scores were consistently below -2 in the region extending from about 10 cM centromeric from the Factor IX locus (F9) to the colorblindness region. This study does not replicate previous reports of linkage of MDI to Factor IX (Xq27) and colorblindness region (Xq28) chromosomal markers in other kindreds. 相似文献
6.
A Lowy P M Flood A Tominaga J A Drebin J Dambrauskas R K Gershon M I Greene 《Journal of immunology (Baltimore, Md. : 1950)》1984,132(2):640-643
We have analyzed the first-order suppressor factor secreted by an azobenzenearsonate (ABA)-specific T suppressor cell (Ts) hybridoma. Treatment of the factor with 5 mM dithiothreitol (DTT) yields two fragments with distinct phenotypes and functional capabilities. One fragment is bound by a monoclonal anti-I-J antibody, the other is not. Further, although neither molecular fragment by itself is sufficient to suppress an ABA response, a mixture of the two reconstitutes the suppressive activity. The I-J- portion of the first-order suppressor factor (TsF1) presumably guides the antigen specificity; activity of the ABA-specific Ts I-J- TsF1 factor can be reconstituted with an I-J+ subunit of a TsF molecule of either sheep red blood cell (SRBC) or ABA specificity. The genetic restriction for Igh-linked determinants of the ABA/SRBC hybrid TsF molecules is influenced by the I-J+ portion, regardless of the original antigen specificity of that molecule. The data support a two-subunit TsF model. Polyclonal ABA-specific TsF1 molecules appear to resemble the monoclonal factor in structure. 相似文献
7.
The mature enteric nervous system (ENS) is characterized by a degree of neuronal phenotypic diversity and independence of central nervous system control unequaled by any other region of the peripheral nervous system. Studies that have utilized the immunocytochemical demonstration of neurofilament protein and explanation of primordial gut with subsequent growth in culture have indicated that the neural crest precursors of enteric neurons are already committed to the neuronal lineage when they colonize the bowel; however, neuronal phenotypic expression occurs within the gut itself. It is likely that precursors able to give rise to each type of neuron found in the mature ENS are present among the earliest neural crest émigrés to reach the bowel. In mice a proximodistal wave of neuronal phenotypic expression occurs that does not appear to reflect the descent of neuronal precursors. This observation, the known plasticity of developing neural crest-derived neurons, and the demonstration of a persistent population of proliferating neuroblasts in the gut raise the possibility that enteric neuronal phenotypic expression is influenced by the enteric microenvironment. 相似文献
8.
Ten amphipod (Crustacea) species from the inland waters of Israel and Sinai have been identified (Gammarus syriacus, G. pseudosyriacus, Echinogammarus n. sp., E. foxi, E. veneris, Corophium orientalis, Orchestia cavimana, O. platensis, Bogidiella hebraea and Metacrangonyx n. sp.). These species display two principal distribution patterns: a marine origin derived pattern and a north-south pattern typical of the freshwater fauna of the Levant. The understanding of these patterns aids in the elucidation of the zoogeography of the region. Within their ranges the common Gammarus and Echinogammarus species display differences in preference for current velocities, salinities and habitat types. The influence of man-induced habitat destruction on the amphipod fauna is also discussed. 相似文献
9.
Segregation and linkage analyses in families of patients with bipolar,unipolar, and schizoaffective mood disorders.
下载免费PDF全文
![点击此处可从《American journal of human genetics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
L R Goldin E S Gershon S D Targum R S Sparkes M McGinniss 《American journal of human genetics》1983,35(2):274-287
Hypotheses of single major locus transmission (autosomal and X chromosome) of major affective disorder (i.e., bipolar, unipolar, and schizoaffective) are tested using the Elston-Stewart likelihood method of pedigree segregation analysis. The sample consists of families of varying size ascertained through patients treated at the National Institute of Mental Health in Bethesda, Maryland. We test hypotheses on subsamples of families according to: (1) diagnosis of proband (75 bipolar I, 22 bipolar II, 18 unipolar, and six schizoaffective); (2) extreme value of a biological trait in the proband ("low" monoamine oxidase, "low" cerebrospinal fluid serotonin metabolite 5-HIAA); and (3) positive response to lithium in the proband. We cannot find evidence for single major locus transmission of major affective disorder from segregation analysis in any subsample of family even when the diagnostic classification of ill phenotypes is widened to include possible affective "spectrum" diagnoses. In addition, linkage studies of 21 autosomal markers do not provide evidence for single major locus transmission of illness. The maximum lod score, found for 30 families at the MNS locus, was 1.39 at 20% recombination. 相似文献
10.
Targeting of glycoprotein I (gE) of varicella-zoster virus to the trans-Golgi network by an AYRV sequence and an acidic amino acid-rich patch in the cytosolic domain of the molecule. 总被引:10,自引:9,他引:1
下载免费PDF全文
![点击此处可从《Journal of virology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Previous studies suggested that varicella-zoster virus (VZV) envelope glycoproteins (gps) are selectively transported to the trans-Golgi network (TGN) and that the cytosolic domain of gpI (gE) targets it to the TGN. To identify targeting signals in the gpI cytosolic domain, intracellular protein trafficking was studied in transfected cells expressing chimeric proteins in which a full-length or mutated gpI cytosolic domain was fused to the gpI transmembrane domain and interleukin-2 receptor (tac) ectodomain. Expressed protein was visualized with antibodies to tac. A targeting sequence (AYRV) and a second, acidic amino acid-rich region of the gpI cytosolic domain (putative signal patch) were each sufficient to cause expressed protein to colocalize with TGN markers. This targeting was lost when the tyrosine of the AYRV sequence was replaced with glycine or lysine, when arginine was replaced with glutamic acid, or when valine was substituted with lysine. In contrast, tyrosine could be replaced by phenylalanine and valine could be substituted with leucine. Mutation of alanine to aspartic acid or deletion of alanine abolished TGN targeting. Exposure of transfected cells to antibodies to the tac ectodomain revealed that the TCN targeting of expressed tac-gpI chimeric proteins occurred as a result of selective retrieval from the plasmalemma. These data suggest that the AYRV sequence and a second signaling patch in the cytosolic domain of gpI are responsible for its targeting to the TGN. The observations also support the hypothesis that the TGN plays a critical role in the envelopment of VZV. 相似文献