全文获取类型
收费全文 | 6731篇 |
免费 | 633篇 |
国内免费 | 2篇 |
出版年
2023年 | 39篇 |
2022年 | 77篇 |
2021年 | 126篇 |
2020年 | 92篇 |
2019年 | 114篇 |
2018年 | 166篇 |
2017年 | 130篇 |
2016年 | 235篇 |
2015年 | 406篇 |
2014年 | 426篇 |
2013年 | 495篇 |
2012年 | 627篇 |
2011年 | 575篇 |
2010年 | 361篇 |
2009年 | 306篇 |
2008年 | 404篇 |
2007年 | 390篇 |
2006年 | 347篇 |
2005年 | 314篇 |
2004年 | 349篇 |
2003年 | 297篇 |
2002年 | 264篇 |
2001年 | 45篇 |
2000年 | 47篇 |
1999年 | 64篇 |
1998年 | 87篇 |
1997年 | 47篇 |
1996年 | 33篇 |
1995年 | 49篇 |
1994年 | 34篇 |
1993年 | 35篇 |
1992年 | 37篇 |
1991年 | 26篇 |
1990年 | 24篇 |
1989年 | 27篇 |
1988年 | 28篇 |
1987年 | 9篇 |
1986年 | 14篇 |
1985年 | 13篇 |
1984年 | 13篇 |
1983年 | 16篇 |
1982年 | 12篇 |
1981年 | 11篇 |
1980年 | 13篇 |
1978年 | 9篇 |
1976年 | 12篇 |
1975年 | 10篇 |
1974年 | 14篇 |
1973年 | 6篇 |
1968年 | 10篇 |
排序方式: 共有7366条查询结果,搜索用时 187 毫秒
31.
A new isotype sequence (V kappa 27) of the variable region of kappa-light chains from a mouse hybridoma-derived anti-(streptococcal group A polysaccharide) antibody containing an additional cysteine residue. Application of the dimethylaminoazobenzene isothiocyanate technique for the isolation of peptides. 总被引:1,自引:0,他引:1 下载免费PDF全文
The first complete sequence of the variable region of a kappa-light chain (V kappa) from a mouse anti-(streptococcal group A polysaccharide) antibody (immunoglobulin 7S34.1) is reported. Immunoglobulin 7S34.1 was isolated from the ascitic fluid of hybridoma 7S34.1 previously cloned in vitro. A newly developed technique for the isolation of peptides by using pre-column formation of peptide derivatives with dimethylaminoazobenzene isothiocyanate also served to complete the sequence. The sequence of the variable region of the kappa-light chain of immunoglobulin 7S34.1 defines a new mouse V kappa isotype (V kappa 27) and is the first mouse immunoglobulin light-chain variable region to be shown to have an extra cysteine residue at position 48. 相似文献
32.
Dr. Christoph Schubert 《Cell and tissue research》1974,156(1):103-112
Summary Dorsal tubercle and skin of Mertensiella caucasica have been investigated with the electron microscope and enzyme histochemical methods. The epidermis of the tubercle consists of 8–9 cell layers, that of normal dorsal skin of 5–6. The tubercle is filled with large mucous glands which are surrounded by an almost complete layer of smooth muscle cells (myoepithelial cells). Their glandular cells undergo cyclical changes and are characterized by specific secretory granules, which differ from those of the relatively small mucous glands of the normal dorsal skin.In the connective tissue of the tubercle a relatively rich supply of nerve fibres has been found, which in part contain synaptic and dense core vesicles or accumulations of mitochondria. In the normal dorsal skin nerve fibres occur less frequently.The following enzymes have been demonstrated in the mucous glands of the tubercle: SDH, acid phosphatase, unspecific esterases, E 600 resistant esterase.The tubercle seems to stimulate the female cloaca chemically and mechanically. 相似文献
33.
34.
35.
The aims, content, and organisatory structure of a proposed interdisciplinary ecosystem research project in the Wadden Sea
of Schleswig-Holstein (W. Germany) are briefly presented. The project will include research on both fundamental as well as
applied aspects of the Wadden Sea ecosystems and their interaction with local human activities. In contrast to most of the
other completed or currently running ecosystem research projects on tidal coasts, a considerable part of the scientific work
will also deal with aspects of ecosystem management and protection of the various marine and semiterrestrial habitats of the
Wadden Sea. Considerable attention is paid to theoretical and methodological aspects of research on ecosystems and landscape
units. In particular, the adoption of a hierarchical view of complex biological and environmental systems is recommended.
Presented at the VI International Wadden Sea Symposium (Biologische Anstalt Helgoland, Wattenmeerstation Sylt, D-2282 List,
FRG, 1–4 November 1988) 相似文献
36.
37.
38.
Christoph Richter 《Free radical research》1990,8(4):329-334
The norepinephrine analogue meta-iodo-benzylguanidine (MIBG). a substrate for mono(ADP-ribosylation) and inhibitor of eukaryotic ADP-ribosyltransferases. inhibits the prooxidant-induced and spontaneous calcium release from intact rat liver mitochondria without affecting pyridine nucleotide oxidation and hydrolysis. This finding strongly suggests regulation of calcium release by ADP-ribosylation in mitochondria. and may be relevant for the cellular and pharmacological effects of MIBG 相似文献
39.
Induction of accessory cell function of human alveolar macrophages by inhalation of human natural interleukin-2 总被引:1,自引:0,他引:1
Gernot Zissel Walter E. Aulitzky J. Lorenz Christoph Huber J. Müller-Quernheim 《Cancer immunology, immunotherapy : CII》1996,42(2):122-126
Accessory function allows antigen-presenting cells to produce sufficient secondary signals for optimum T cell proliferation
and interleukin-2 (IL-2) production. Alveolar macrophages are inferior accessory cells compared to monocytes (PBM). We report
here that the accessory index (AI) of alveolar macrophages and PBM of patients with lung metastases of solid tumors treated
with inhalations of human natural IL-2 (hnIL-2) increased following its administration (P<0.005). The accessory index was significantly elevated from baseline values after 2 weeks of inhalation of 300 000 IU hnIL-2/day
(8.2±10.2 compared to 1.1±1; P<0.001). The inhalation of 150 000 IU also induced increases in the index (AI = 2.3±1.9), however, without reaching statistical
significance. In addition at 300 000 IU IL-2/day a significant increase in the accessory index was observed for PBM (4±2.5;
P<0.05). The indices of PBM and alveolar macrophages prior to inhalation showed a significant negative correlation with the
age of the patients (r
s = – 0.5; r
s = – 0.8, respectively; P<0.03 for all comparisons). Our data demonstrate that the inhalational application of hnIL-2 enhances the accessory function
of alveolar macrophages and, to lesser extent, the accessory index of PBM, indicating the occurrence of pharmacological immunostimulation.
Received: 16 August 1995 / Accepted: 4 January 1996 相似文献
40.