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121.
BACKGROUND: Hyaluronan (HA) synthesis is frequently observed in malignant mesothelioma cells, whereas it is rarely found in lymphoma cells. Previous studies have reported that a high HA concentration in the serum was related to poor prognosis in lymphomas, although the mechanism was not elucidated. We recently encountered a case of anaplastic large cell lymphoma with an HA-rich, massive, lymphomatous effusion. Several studies were performed to clarify the character of this unusual lymphoma and to observe whether the lymphoma cells synthesized HA. CASE: A 59-year-old female was admitted with abdominal pain. Radiologic studies revealed a pleural effusion and paraaortic lymph node swelling. A biopsied specimen was compatible with anaplastic large cell lymphoma. Detailed cytologic observations revealed that the lymphoma cells in the pleural effusion had alcian blue-positive, productive material in the prominent Golgi area and microvillous structures on the surface. Further studies found that most of the lymphoma cells had HA-binding protein and expressed CD44 antigen, a receptor for HA. In addition, the HA concentration in the supernatant of the primary culture cells was extremely high and increased time dependently. CONCLUSION: These observations suggest that the lymphoma cells synthesized and released HA. Interactions of the released HA and CD44 on the surface might play an important role in the peculiar serosal growth of lymphoma cells. 相似文献
122.
Yasukazu Nakamura Takakazu Kaneko Shusei Sato Mamoru Mimuro Hideaki Miyashita Tohru Tsuchiya Shigemi Sasamoto Akiko Watanabe Kumiko Kawashima Yoshie Kishida Chiaki Kiyokawa Mitsuyo Kohara Midori Matsumoto Ai Matsuno Naomi Nakazaki Sayaka Shimpo Chie Takeuchi Manabu Yamada Satoshi Tabata 《DNA research》2003,10(4):181-201
123.
Kishida M Johanning KM Bengtson DA Specker JL 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》1998,119(1):415-421
Intestinal uptake of lipovitellin (LV) from brine shrimp (Artemia franciscana) in larval inland silversides (Menidia beryllina) and striped bass (Morone saxatilis) was described using immunocytochemistry. Polyclonal antisera were raised against two subunits of LV (LV68 and LV190). When tested by immunocytochemistry, anti-LV68 showed cross-reactivity with some of the pancreatic cells especially in inland silversides. Therefore anti-LV190 was used to localize immunoreactive LV. Inland silversides at 14 days after hatching were fed Artemia nauplii and then sampled 4, 8, 12 hr after feeding. Similar experiments were carried out by using striped bass at 5 days and 15 days of age. They were sampled at 2, 4, 8, and 12 hr after feeding. Anterior enterocytes showed no evidence of uptake; however, the brush border of the cells of inland silversides reacted with the antiserum. Posterior enterocytes took up the LV and/or, possibly, their immunoreactive breakdown products. The pattern of uptake included accumulation in supranuclear vacuoles and digestion in supranuclear vacuoles, as suggested by the decay of the immunoreactivity over time. Thus, the posterior intestine of these larval fishes is the site of uptake and digestion of LV, an important nutritive component in the food of many larval fishes; this supports earlier findings using non-nutritive marker proteins. 相似文献
124.
Takusaburo Ebina Yoshiaki Fujimiya Tomohiro Yamaguchi Naoko Ogama Hiroko Sasaki Noriko Isono Youichi Suzuki Ryuichi Katakura Kazuya Tanaka Kinya Nagata Shoichi Takano Keiji Tamura Kazuko Uno Tsunataro Kishida 《Biotherapy》1998,11(4):241-253
Adoptive immunotherapy using MHC-nonrestricted-lymphocytes, peripheral blood T cells and NK cells was devised. Peripheral blood mononuclear cells (3 x 107) were selected by immobilization to anti-CD3 monoclonal antibody for 4 days and cultured for 2 weeks in the presence of IL-2. Thereafter they were reactivated by 500 U/ml of IFN- and 1000 U/ml of IL-2 for 1 hour. Enhancement of NK and LAK activities was confirmed. Peripheral blood T cells proliferated in response to immobilized anti-CD3 antibody (3% to 30%). Approximately 6 x 109 BRM-activated killer (BAK) cells composed of CD56+ T cells and CD56+ NK cells, were dispensed to cancer patients via intravenous drip infusion. Nine patients were treated with BAK cells every 2 weeks or every month on an outpatient basis. During the course of adoptive immunotherapy, the crossed affinity immunoelectrophoresis (CAIE) pattern of serum immunosuppressive acidic protein (IAP) was analysed. Both the production and glycosylation pattern of IAP is changed in response to tumor enlargement and may therefore act as a marker of the disease progression. During the course of BAK therapy, the glycosylation IAP pattern of 6 patients changed from tumor (T) to normal (N). In addition, the performance status of all patients was maintained at 90–100% of the Karnofsky scale and any side effects including fever were not observed during treatments with BAK cells. Moreover, the overall quality of life (QOL) of the patients, scored at the Face scale was favorable. In addition, blood levels of activated T cells producing IFN- were assayed as an indication marker of BAK therapy. The normal range of IFN- producing T cells comprised 6.9 ± 0.9% of peripheral blood mononuclear cells (PBMC), according to a single cell FACScan analyses of PBMCs derived from normal individuals. IFN- producing T cells of Patients No. 8 and 9, who received extensive chemotherapy before initiation of BAK therapy, comprised only 0.2% and 2% of PBMC, respectively. These patients died 3 and 6 months after beginning BAK therapy. Peripheral blood T cells of Patients Nos. 1–7 proliferated in response to immobilized anti-CD3 antibody and the frequency of IFN- producing T cells in PBMC preparation of these patients were over 3% before initiation of BAK therapy. Since our data show a positive correlation between survival time and initial T cell counts, a low frequency of these cells may contraindicate BAK therapy. 相似文献
125.
Photosynthetic CO2 fixation was studied using cells of Rhodospirillumrubrum grown heterotrophically on malate or butyrate. Ratesof CO2 fixation were higher in the malategrown cells than inthe butyrate-grown bacteria but ribulosebisphosphate (RUP2)carboxylase/oxygenase activities were higher in the extractsprepared from the butyrate-grown bacteria. The photosyntheticCO2 fixation in the butyrate-grown R. rubrum cells was inhibitedby KCN, and the inhibitory effect of O2 on CO2 fixation wasreversed when cells were returned to an N2 atmosphere. In themalate-grown cells, photosynthetic CO2 fixation was insensitiveto KCN and the inhibitory effect exerted by O2 was practicallyirreversible. 14CO2 was not incorporated into glycolate by either malate-or butyrate-grown cells in an N2 atmosphere, but small amountsof labeled glycolate were found in malate- and butyrate-growncells in air or 100% O2. Glycolate excreted by these cells in100% O2 was measured colorimetrically and its identity establishedby mass spectrometry. When the O2 atmosphere was labeled with18O2, only one of the carboxyl oxygens of the excreted glycolatewas labeled, and the enrichment of 18O in this carboxyl oxygenrelative to the 18O2 provided was greater than 80%. These studiesshow that significant glycolate production by R. rubrum onlyoccurs in the presence of O2 and that in both malateand butyrate-growncells, the glycolate so formed is presumably produced via RuP2oxygenase.
1 Paper No. 46 in the series "Structure and Function of ChloroplastProteins", and research supported in part by research grantsfrom the Japanese Ministry of Education (No. 211113), the TorayScience Foundation (Tokyo), and the Nissan Science Foundation(Tokyo). (Received August 19, 1978; ) 相似文献
126.
Previous studies with 14C-labeled synthetic peptides demonstrated that prolyl hydroxylase, which synthesizes the hydroxyproline in collagen, preferentially hydroxylates the fourth triplet from the NH-terminal end of the peptide (Pro-Pro-Gly)5. In the experiments reported here, the prolyl hydroxylase reaction was investigated further by preparing chemically modified derivatives of (Pro-Pro-Gly)5 and by synthesizing 14C-labeled preparations of (Pro-Pro-Gly)10. Essentially, the same kcat value was found for the hydroxylation of (Pro-Pro-Gly)5, N-acetyl-(Pro-Pro-Gly)5, (Pro-Pro-Gly)5 methyl ester, (Pro-Pro-Gly)10, and for larger polypeptide substrates of the enzyme. It appeared therefore that preferential hydroxylation of specific triplets in peptides of the structure (Pro-Pro-Gly)n cannot be explained by differences in the kinetic constants for individual triplets. Hydroxylation of 14C-labeled preparations of (Pro-Pro-Gly)10 demonstrated that the ninth triplet was preferentially hydroxylated over any other triplet. The results were best explained by the hypothesis that prolyl hydroxylase has an asymmetric active site in which binding subsites are located adjacent to but not symmetrical with the catalytic subsite. 相似文献
127.
Phosphatase activities and osmium reduction in cell organelles ofMicrasterias americana 总被引:1,自引:1,他引:0
Tetsuko Noguchi 《Protoplasma》1976,87(1-3):163-178
Summary Organelles in resting and growing cells ofMicrasterias americana were examined using electron microscopy after cytochemical procedures for four kinds of phosphatases, acid phosphatase (ACPase), alkaline phosphatase (ALPase), thiamine pyrophosphatase (TPPase), and inosine diphosphatase (IDPase), and osmium tetroxide reduction. Special attention was paid to activities in the Golgi apparatus.In resting cells, positive reactions for ACPase and TPPase were observed in all cisternae of the dictyosome, especially in the peripheral parts. A positive IDPase reaction was seen in one central cisterna and was frequent in the distal-most cisterna. Reduction of osmium tetroxide was seen in the proximal cisternae.In early growing cells, the dictyosomes gave positive reactions for ACPase in the proximal cisternae and the distal cisterna, while in late growing cells only in proximal cisternae. Both in early and late growing cells, the dictyosomes were positive for TPPase and IDPase in the distal cisternae and vesicles derived from the distal cisternae, and for the reduction of osmium tetroxide in the proximal cisternae. ALPase activity was detected in the growing cell wall but not in the dictyosome. 相似文献
128.
129.
Katsuhiko Inouye Yuji Kobayashi Yoshimasa Kyogoku Yasuo Kishida Shumpei Sakakibara Darwin J. Prockop 《Archives of biochemistry and biophysics》1982,219(1):198-203
The collagen-like polytripeptide (hydroxyproline-proline-glycine)10 was synthesized with a solid-phase procedure. Analytical ultracentrifugation indicated that the peptide in aqueous solution at 6 °C had a molecular weight of 2550, the expected size of a single chain. The peptide had a relatively small negative optical rotation at 578 nm, and it did not show a thermal transition as is seen with collagen or collagen-like polytripeptides which form triple helices. At low temperatures in aqueous solution, the circular dichroism spectrum was similar to that of triple-helical collagen and collagen-like peptides in that there was a positive peak at 224 nm and a negative peak at 200 nm. The amplitudes of the peaks, however, were considerably less than the peaks obtained with triple-helix proteins and peptides. Since (proline-proline-glycine)10 was triple helical under the same conditions, the results demonstrated that hydroxyproline in the X-position of the repeating -glycine-X-Y- sequences decreases rather than increases, the thermal stability of the triple helix. This positional specificity cannot be explained by any of the current models for the structure of the triple helix or any of the current proposals for how hydroxyproline stabilizes the structure. 相似文献
130.
trans -Golgi network (TGN), and the changes in its structure and behavior throughout the cell cycle of a unicellular green alga,
Botryococcus braunii, were examined with deep-etching replicas and in cryo-fixed/freeze-substituted specimens. In interphase cells, the TGN consisted
of a hemispherically shaped cisterna (TGN-cisterna) with regularly distributed pores on the surface and a tubular network
(TGN-tubules) with clathrin-coated vesicles. The TGNs changed their structure drastically throughout the cell cycle. The TGN-cisterna
disappeared from the beginning of nuclear division to the completion of the cell wall, in contrast that TGN-tubules with the
clathrin-coated vesicles were always observed. The TGN-tubules produced at least five other kinds of vesicles depending on
the stage of the cell cycle: 200-nm vesicles with fibrillar substances and multivesicular bodies in interphase, 180–240 nm
vesicles during cell division, and 400–450 nm vesicles containing fibrils and small masses of electron-dense substances, and
200-nm vesicles containing electron-dense spherical substances just after cell division. During cell wall formation, TGN-tubules
were small and had only a few clathrin-coated vesicles. After cell wall formation, TGN-tubules grew and a TGN-cisterna with
pores appeared again.
Received 19 October 1998/ Accepted in revised form 1 March 1999 相似文献