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121.
H. Schwegler P. K. D. Pilz M. Koch M. Fendt R. Linke P. Driscoll 《Behavior genetics》1997,27(6):579-582
To investigate the emotional reactions of two rat strains selectively bred for good and poor two-way avoidance acquisition (RHA/Verh and RLA/Verh), male animals of both strains were tested in an acoustic startle response test. They received 40 acoustic stimuli followed by 10 electric foot shocks and another 30 acoustic stimuli. RLA/Verh rats showed a significantly higher startle response compared to RHA/Verh animals, indicating a stronger emotional reaction to acoustic stimuli. In addition, the former showed a stronger response to foot shocks. Combined with earlier findings, we conclude that selection for two-way avoidance learning does not result in cognitive defects in the RLA/Verh strain but, rather, in stronger emotional reactions to fearful stimuli. 相似文献
122.
In a series of approximately 80,000 lymph nodes, amyloid deposition was found in 18; 12 of those nodes were selected, on the basis of availability of specimens, for investigation by immunohistochemical typing to identify the protein of origin and by correlation with morphologic criteria and clinical information. Four patterns of amyloid deposition were identified: lymph node vessel involvement, follicular deposition, diffuse deposition, and a combination of follicular and diffuse deposition. All cases were classified immunohistochemically with the amyloid type-specific antisera anti-AA, anti-A lambda, anti-A kappa, anti-ASc1, and anti-AF. Immunoglobulin-derived protein (AL) in lymph nodes was found in every case of isolated amyloidosis, lymphoplasmacytic/lymphoplasmacytoid immunocytoma, plasmacytoma, and idiopathic amyloidosis. Among the cases of AL amyloidosis were nine of A lambda and one of the A kappa type. AA protein was present in two cases of reactive systemic amyloidosis. There was no useful morphologic correlation with the immunohistochemically identified amyloid types. 相似文献
123.
Properties of the major antigens of rat and human Pneumocystis carinii. 总被引:17,自引:11,他引:17
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The major rat and human Pneumocystis carinii antigens were analyzed for their susceptibility to treatment with enzymes and other procedures by immunoblotting, immunofluorescence, and light microscopy. Carbohydrate residues were further analyzed by lectin-binding experiments. The 116-kilodalton (kDa) band of rat P. carinii was susceptible to proteolytic (e.g., trypsin) and glycolytic (e.g., Zymolyase) treatments but not to a variety of other procedures (e.g., lipase). This moiety reacted strongly with concanavalin A and wheat germ agglutinin, indicating the presence of mannosyl or glucosyl and N-acetylglucosamine residues. Immunofluorescence staining and surface labeling suggested that the 116-kDa antigen was located on the P. carinii cell wall. The 45- and 50-kDa bands were as sensitive as the 116-kDa band to degradative treatments when studied after immobilization onto nitrocellulose but were more resistant to proteolytic enzymes when studied in situ on whole organisms. These moieties exhibited poor binding to lectins and reactivity by surface-labeling procedures. The 116-kDa band of human P. carinii appeared to be a glycoprotein with characteristics similar to those of its counterpart in rats, whereas the human P. carinii 40-kDa band exhibited protein and carbohydrate properties more closely related to those of the 45- and 50-kDa rat-derived antigens. We conclude that P. carinii antigens are complex glycoproteins and that this information will be helpful in developing strategies for their isolation and purification and study of their function. 相似文献
124.
E. P. Rieber H. W. v. Heyden R. P. Linke J. G. Saal G. Riethmüller H. D. Waller 《Journal of molecular medicine (Berlin, Germany)》1976,54(21):1011-1019
Zusammenfassung Bei vier Patienten mit Haarzell-Leukämie wurden die leukämischen Zellen auf das Vorkommen von Oberflächenimmunglobulinen und Fc-Rezeptoren sowie die Stimulierbarkeit mit verschiedenen Mitogenen hin untersucht. Die Analyse dieser Eigenschaften erfolgte mit Hilfe einer kombinierten zytochemisch-radioautographischen Technik, bei der die radioaktiv markierten Zellen durch den Nachweis des Tartrat-resistenten Isoenzyms der sauren Phosphatase als Haarzellen identifiziert werden konnten. Für den Nachweis der Oberflächenimmunglobuline wurden125I-markierte (Fab')2-Fragmente von monospezifischen Antikörpern gegen schwere Immunoglobulinketten verwendet. Bei zwei Patienten wurden auf der Oberfläche der isoenzymhaltigen Zellen - und -Immunglobulinketten nachgewiesen, die bei einem großen Teil dieser Zellen gleichzeitig auf der Zelloberfläche ausgedrückt waren. Bei einem Patienten zeigten die isoenzymhaltigen Zellen - und -Ketten und bei einem vierten Patienten nur -Ketten. Bei einer Patientin konnten - und -Ketten nach einer in vitro-Kultur von 14 Tagen in Humanserum-freiem Medium in gleicher Weise nachgewiesen werden wie auf frischen Zellen, was für eine Synthese der Oberflächenimmunglobuline durch die Haarzellen selbst spricht. In der indirekten Immunfluoreszenztechnik wurden die Oberflächenimmunglobuline sehr schnell über einem Zellareal konzentriert, in dem auch Latexpartikel nach der Phagozytose lokalisiert waren. Mit Hilfe von125I-markierten Aggregaten von humanem IgG konnten bei allen vier Patienten Fc-Rezeptoren auf fast 100% der isoenzymhaltigen Zellen nachgewiesen werden. Eine deutliche, wenn auch geringe Stimulation der isoenzymhaltigen Zellen konnte beobachtet werden, wenn die Haarzellen mit Pokeweed-Mitogen oder Lima-Bohnen-Lektin (B- und T-Zell-Mitogene) kultiviert wurden, nicht jedoch, wenn die Stimulation mit Phytohämagglutinin oder Concanavalin-A (T-Zell-Mitogene) erfolgte. Bei keinem der drei untersuchten Patienten bildeten die Haarzellen Spontanrosetten mit Schaferythrozyten.Die Arbeit wurde von der Deutschen Forschungsgemenschaft im Rahmen der Forschergruppe biochemische und immunologische Grundlagen der Leukämie- und Tumortherapie unterstützt 相似文献
125.
Jurjen Schirm Dirk S. Luijt Geke W. Pastoor Johan M. Mandema F. Peter Schrder 《Journal of medical virology》1992,38(2):147-151
Eleven hundred and thirty-three clinical specimens submitted to the laboratory for diagnosis of respiratory virus infections were tested by direct immunofluorescence (DIF) for respiratory syncytial virus (RSV), by shell vial culture, and by conventional cell culture. The shell vial cultures were stained with 8 different monoclonal antibodies both 1 day and 3-7 days after inoculation. In order to limit the cost and the workload, mixtures of monoclonal antibodies were used. Coverslips with HEp-2 cells were incubated with a mixture of FITC-labeled monoclonal antibody to RSV and nonlabeled monoclonal antibody to adenovirus. When no RSV positive IF staining was observed after the first incubation step, the same coverslip was incubated once more with FITC-labeled anti-mouse antibody. A positive reaction at this stage indicated the presence of adenovirus. Similarly, cultures of tertiary monkey kidney cells were investigated with a mixture of two FITC-labeled monoclonals to the influenza viruses A and B and three nonlabeled monoclonals to the parainfluenza viruses 1, 2 and 3. If influenza virus or parainfluenza virus was detected, the exact type was determined by staining different parts of a duplicate coverslip. Shell vial cultures for cytomegalovirus (CMV) were always performed separately on human embryonic lung fibroblasts. Using this approach, we detected RSV (n = 248), CMV (n = 42), parainfluenza virus (n = 31), influenza virus (n = 28), and adenovirus (n = 6), in most cases after only one day of culture. For RSV, the sensitivity of the shell vial method was too low (74%) to allow omission of DIF (sensitivity 95%).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
126.
Eva-Bettina Brcker Ludwig Suter Josef Brüggen Dirk J. Ruiter Egon Macher Clemens Sorg 《International journal of cancer. Journal international du cancer》1985,36(1):29-35
The phenotypic changes in human melanoma cells during the course of tumor progression were studied with monoclonal antibodies (MAbs) against the melanoma-associated antigens (MAA) M.2.2.4, H.2.8.10, K.1.2, A.1.43, and A.10.33, and HLA-(A,B,C and D). Cryostat sections of 172 primary melanomas of the skin, 157 melanoma metastases and 56 nevi were investigated with an indirect immunoperoxidase method. Phenotypic heterogeneity was observed within lesions at all stages, and also within different tumors of the same patients. Despite this heterogeneity, principles of antigen expression were found. From the reaction pattern of MAbs, the following classifications of antigens were derived: "constitutive" markers of nevomelanocytic cells (M.2.2.4 and H.2.8.10) were found expressed over a wide range of local and systemic tumors. One MAA, K.1.2 (Suter et al., 1985), that declines with progression of melanoma, was classified as an "early" antigen, whereas MAA that appear in primary melanoma in proportion to invasiveness, and which are expressed in metastases of lymph nodes and visceral organs (A.1.43, and A.10.33), were classified as "late" markers of tumor progression. HLA-antigens were classified as "intermediate" markers, HLA-A,B,C, as an "early-intermediate", and HLA-DR as a "late-intermediate" marker. The occurrence of class II HLA, A.1.43-, and A.10.33-positive tumor cells in primary melanoma indicates a high metastatic potential of tumors, independent of tumor thickness. The data show that local and systemic progression of melanoma is associated with qualitative changes in tumor cells which can be recognized by MAbs. 相似文献
127.
Dirk Martens Martin J. Lohse Bernhard Rauch Ulrich Schwabe 《Naunyn-Schmiedeberg's archives of pharmacology》1987,336(3):342-348
Summary The aim of the present study was the characterization of adenosine receptors in isolated rat ventricular myocytes. The CAMP-levels of rat ventricular myocytes in the presence of 1 mol/l isoprenaline were reduced by up to 48% by adenosine analogues; the rank order of potency was: R-N6-phenylisopropyladenosine (IC50 60 nmol/1), 5-N-ethylcarboxamidoadenosine (IC50 360 nmol/l) and S-N6-phenylisopropyladenosine (IC50 16 ol/l). The adenosine receptor antagonist XAC (xanthine amine congener) antagonized the effect of R-N6-phenylisopropyladenosine in a concentration-dependent manner with a Ki-value of 20 nmol/l. The A1 receptor-selective radioligand R-N6-125I-p-hydroxyphenylisopropyladenosine bound to membranes prepared from rat ventricular myocytes in a saturable manner with a B
max of 17.7 fmol/mg protein and a K
D-value of 1.1 nmol/l. Adenosine analogues competed for the binding with the same rank order of potency as for the inhibition of the isoprenaline-induced cAMP-increase. GTP inhibited radioligand binding with an IC50-value of 73 ol/l. These results suggest the presence of A1 adenosine receptors on rat ventricular myocytes, which mediate an inhibition of adenylate cyclase. The receptors may be responsible for the effects of adenosine and its analogues on the heart.Abbreviations
125I-HPIA
R-N6-125I-p-hydroxyphenylisopropyladenosine
- PIA
N6-phenylisopropyladenosine
- NECA
5-N-ethyl-carboxamidoadenosine
- XAC
8-4-[([(2-aminoethyl)aminocarbonyl]methyl)oxy]phenyl-1,3-dipropylxanthine (xanthine amine congener)
- Ro 20-1724
4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone
- ScAMPTME
2-O-monosuccinyladenosine-3,5-cyclic monophosphate tyrosyl methyl ester
- HEPES
N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid
- GTP
guanosine-5-tri-phosphate
Send offprint requests to D. Martens 相似文献
128.
The liver is a major site for synthesis and catabolism of plasma proteins. Albumin has various binding sites for anionic drugs,
1acid glycoprotein possesses a single binding site for cationic drugs. In spite of extensive protein binding, the liver can efficiently remove drags from the circulation. Intrahepatic dissociation of the drag-protein complex may involve dissociation-limited debinding under non-equilibrium conditions or surface interaction-facilitated dissociation phenomena. During liver or renal disease and acute-phase conditions plasma protein binding of drugs may be affected. Changes in the unbound drag fraction do not always result in proportional changes in clearance or distribution volume. Potential changes in the unbound concentration in steady-state as well as the fluctuations in total plasma levels depend on the extent of protein binding of a drug, the relative change in the unbound drug fraction, type of clearance, the size of the distribution volume, route of administration as well as concomitant changes in intrinsic (cellular) clearance function. Optimization of dosage regimens for certain drags and interpretation of liver function tests with diagnostic dyes may largely benefit from determination of the unbound rather than the total concentration of the drags involved.Part of this work was supported by Grant 900-521-078 from MEDICON, which is subsidized by The Netherlands' Organization of Pure Research. 相似文献
129.
目的:探讨超声联合血清甲状腺过氧化物酶抗体(TPO–Ab)、甲状腺球蛋白抗体(Tg–Ab)评价桥本甲状腺炎(HT)临床进程的应用价值。方法:选择2021年9月至2022年8月贵州航天医院接诊的HT患者100例纳入观察组,另选择同期于贵州航天医院体检的健康者100例纳入对照组,两组研究对象均行彩色多普勒超声及血清TPO–Ab、Tg–Ab检查。比较两组研究对象血清TPO–Ab与Tg–Ab水平,并分析观察组患者术后病理或空心针穿刺活检组织病理学分级情况,以及观察组患者不同术后组织病理学分级患者血清TPO–Ab与Tg–Ab水平。以术后病理或空心针穿刺活检组织病理学分级为标准,评价超声、血清TPO–Ab与Tg–Ab单独及联合检测对观察组患者组织病理学分级的诊断准确度。结果:观察组患者血清TPO–Ab及Tg–Ab水平均高于对照组健康者,差异具有统计学意义(P <0.05)。观察组中,组织病理学分级为Ⅰ级的患者有58例,Ⅱ级有30例,Ⅲ级有12例;Ⅰ级患者血清TPO–Ab与Tg–Ab水平均低于Ⅱ、Ⅲ级患者,Ⅱ级患者血清TPO–Ab与Tg–Ab水平均低于Ⅲ级患者,差异均具有统计学意义(P <... 相似文献