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31.
Frequent co-localization of Cox-2 and laminin-5 gamma2 chain at the invasive front of early-stage lung adenocarcinomas 总被引:7,自引:0,他引:7
Niki T Kohno T Iba S Moriya Y Takahashi Y Saito M Maeshima A Yamada T Matsuno Y Fukayama M Yokota J Hirohashi S 《The American journal of pathology》2002,160(3):1129-1141
Laminin-5 is an extracellular matrix protein that plays a key role in cell migration and tumor invasion. Cox-2 is an induced isoform of cyclooxygenases that plays an important role in carcinogenesis, suppression of apoptosis, angiogenesis, and metastasis of colon cancer. We report frequent co-expression of cox-2 and laminin-5 at the invasive front of early-stage lung adenocarcinomas. We investigated the expression of cox-2 and laminin-5 immunohistochemically in 102 cases of small-sized lung adenocarcinoma (maximum dimension, 2 cm or less). Cox-2 and laminin-5 were expressed in 97 (95.1%) and 82 (80.4%) cases, respectively. Both were preferentially localized in cancer cells at the cancer-stroma interface, although cox-2 tended to show a diffuse staining pattern in some cases. A comparison of their staining patterns revealed a striking similarity in their distribution in 24 cases, and a partial overlap between their localization in another 20 cases. Moreover, an overall correlation was found between the expression levels of cox-2 and laminin-5 (P = 0.018). To gain insight into the mechanisms that regulate the expression of these proteins, we additionally studied their expression in 58 cases of stage I lung adenocarcinoma, in which p53 status was determined by immunohistochemistry, polymerase chain reaction-single strand conformation polymorphism analysis, and direct sequencing. The results showed that tumors with mutant p53 tended to express more cox-2 than those with wild-type p53 (P = 0.080). Also, tumors that overexpressed p53 had higher levels of cox-2 and laminin-5 than those without p53 overexpression (P = 0.032 and 0.047, respectively). Further immunohistochemical analysis showed that tumors that overexpressed both epidermal growth factor receptor (EGFR) and erbB-2 had higher levels of cox-2 and laminin-5 than those without concomitant overexpression of these proteins (P = 0.014 and P = 0.018, respectively). To see whether EGFR signaling is involved in cox-2 and laminin-5 expression, we further conducted in vitro analyses using six lung adenocarcinoma cell lines (A549, HLC-1, ABC-1, LC-2/ad, VMRC-LCD, and L27). Western blot analyses showed that cox-2 mRNA levels, and to a lesser extent laminin-5 gamma2 mRNA levels, correlated with the expression levels of erbB-2 and the phosphorylated form of MAPK/ERK-1/2 protein. The addition of transforming growth factor-alpha increased both cox-2 and laminin-5 gamma2 mRNA levels in A549, ABC-1, and L27 with different kinetics; the induction of cox-2 occurred earlier than that of laminin-5 gamma2. Finally, the migration of ABC-1 cells was inhibited by MAP kinase kinase inhibitor PD98059 and a selective cox-2 inhibitor NS-398. In contrast, the migration of A549 cells was inhibited by PD98059, but much less effectively by NS-398. These results suggest that co-stimulatory mechanisms may exist that increase the expression of cox-2 and laminin-5 at the invasive front of lung adenocarcinomas and that EGFR signaling could be one of the mechanisms. Further investigations are warranted concerning the role of cox-2 and laminin-5 in cancer cell invasion and the significance of p53 and EGFR signaling in the regulation of cox-2 and laminin-5 expression. 相似文献
32.
33.
Ikegaya H Iwase H Zheng HY Nakajima M Sakurada K Takatori T Fukayama M Kitamura T Yogo Y 《Journal of virological methods》2005,126(1-2):37-43
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time. 相似文献
34.
Yasuo Kawakami Kimitaka Nakazawa Toshiro Fujimoto Daichi Nozaki Mitsumasa Miyashita Tetsuo Fukunaga 《European journal of applied physiology》1994,68(2):139-147
Series cross-section images of the upper extremity were obtained for four men by magnetic resonance imaging (MRI) and anatomical cross-sectional areas (ACSA) of elbow flexor muscles [biceps brachii (BIC), brachialis (BRA), brachioradialis (BRD)] and extensor muscles [triceps brachii (TRI)] were measured. Physiological cross-sectional area (PCSA) was calculated from the muscle volume and muscle fibre length, the former from the series ACSA and the latter from the muscle length multiplied by previously reported fibre/muscle length ratios. Elbow flexion/extension torque was measured using an isokinetic dynamometer and the force at the tendons was calculated from the torque and moment arms of muscles measured by MRI. Maximal ACSA of TRI was comparable to that of total flexors, while PCSA of TRI was greater by 1.9 times. Within flexors, BRA had the greatest contribution to torque (47%), followed by BIC (34%) and BRD (19%). Specific tension related to the estimated velocity of muscle fibres were similar for elbow flexors and extensors, suggesting that the capacity of tension development is analogous between two muscle groups. 相似文献
35.
Monoclonal antibodies(moAbs) reactive with melatonin(MT) were produced using MT, coupled to bovine serum albumin(BSA) with the Mannich reaction, as immunogen and conventional hybridoma techniques. Hybridoma clones secreting the moAbs were selected by an enzyme-linked immunosorbent assay system using MT-carboxymethylchitin and BSA as screening antigens. The moAbs from 6 clones were characterized by a cross-reactivity test using radioimmunoassay with 125I-labelled MT. The moAbs recognized MT but hardly recognized other analogues except for N-acetylserotonin with a crossreactivity of 0.81%. An inhibition curve for MT was obtained in the range of 50 pg to 100 ng and 1.4 ng of MT inhibited the value of the assay by half. There is interference from some unknown source in human serum. 相似文献
36.
Helicobacter pylori seropositivity and IL-1B C-31T polymorphism among Japanese Brazilians 总被引:2,自引:0,他引:2
Uno M Hamajima N Ito LS Oba SM Marie SK Shinjo SK Onda H Saito T Takezaki T Tajima K Tominaga S 《International journal of molecular medicine》2002,10(3):321-326
We reported previously that anti-Helicobacter pylori antibody seropositivity (HP+) had an association with interleukin 1B (IL-1B) C-31T genotype, especially among smokers. This study examined the association for Japanese Brazilians. In this cross-sectional study, voluntary participation was announced through Japanese Brazilian communities in Sao Paulo, Curitiba, Mogi das Cruzes, and Mirandopolis; 963 Japanese Brazilians (399 males and 564 females) aged 33-69 years participated. Lifestyle data and peripheral blood were collected. An anti-HP IgG antibody test and genotyping for IL-1B C-31T and IL-1RN 86 bp VNTR were independently conducted. The genotype frequency of the IL-1B polymorphism among 947 individuals was 23.9% for C/C genotype, 45.6% for C/T genotype, and 30.5% for T/T genotype. Sex-age-adjusted odds ratio (aOR) of HP+ was 1.30 (95% confidence interval, 0.94-1.81) for C/T genotype and 1.45 (1.02-2.07) for T/T genotype relative to C/C genotype. The aOR for 127 current smokers was 2.45 (0.91-6.55) for C/T and 3.49 (1.17-10.46) for T/T, while that for 667 never smokers was 1.21 (0.82-1.78) and 1.36 (0.90-2.05), respectively. The corresponding figures were 2.42 (1.16-5.02) and 3.00 (1.33-6.78) for 226 current drinkers, and 1.21 (0.82-1.78) and 1.36 (0.90-2.05) for 667 non-drinkers. The difference in the OR was observed for milk consumption, salty pickled vegetable eating, and physical exercise practice. 4/4 Genotype of IL-1RN 86 bp VNTR was 84.8%, and had no association with the HP seropositivity. The observed association between HP+ and IL-1B -31TT indicated that the genetic trait also influences the susceptibility to HP for Japanese in Brazil. 相似文献
37.
Keiko Wakui Toshiro Nishida Jun-ichiro Masuda Takeshi Itoh Daisuke Katsumata Tsutomu Ohno Yoshimitsu Fukushima 《Journal of human genetics》1991,36(2):149-153
We report a malformed female infant withde novo interstitial deletion of 4q[46,XX,del(4)(q27q28.2)]. The MN blood type analysis of the family members showed that the patient had an intact blood group-MN locus. The locus of the gene responsible for the MN antigen activity is confined to a 4q28.2–4q31.1 segment on the basis of the result of this patient and the previous mapping data. 相似文献
38.
Toshie Harada Hiromi Kawaminami Noriko N Miura Yoshiyuki Adachi Mitsuhiro Nakajima Toshiro Yadomae Naohito Ohno 《Journal of interferon & cytokine research》2006,26(4):235-247
SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. showing antitumor activity. We recently found that the splenocytes from naive DBA/1 and DBA/2 mice are potently induced by SCG to produce interferon- gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-12p70 (IL-12p70), and that GM-CSF plays a key biologic role among these cytokines. In this study, we investigated the contribution of cell-cell contact and soluble factors to cytokine induction by SCG in DBA/2 mice. Cell-cell contact involving intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) was an essential step for the induction of GM-CSF and IFN-gamma by SCG but not for the induction of TNF-alpha or IL-12p70 by SCG. SCG directly induced adherent splenocytes to produce TNF-alpha and IL-12p70. GM-CSF was required for the induction of TNF-alpha by SCG, and in turn, TNF-alpha enhanced the release of GM-CSF and thereby augmented the induction of IL-12p70 and IFN-gamma by SCG. Neutralization of IL-12 significantly inhibited the induction of IFN-gamma by SCG. We concluded that induction of GM-CSF production by SCG was mediated through ICAM-1 and LFA-1 interaction, GM-CSF subsequently contributed to further cytokine induction by SCG, and reciprocal actions of the cytokines were essential for enhancement of the overall response to SCG in DBA/2 mice. 相似文献
39.
We studied the patterns of membrane potential changes in vocal cord tensor motoneurons, i.e. cricothyroid muscle motoneurons (CTMs), during fictive breathing, vocalization, coughing, and swallowing in decerebrate paralyzed cats to determine the nature of central drives to CTMs during these behaviors. CTMs were identified by antidromic activation from the superior laryngeal nerve. During breathing, CTMs always depolarized during the inspiratory phase, and sometimes depolarized during the expiratory phase as well. During vocalization, CTMs strongly depolarized. During coughing, CTMs exhibited depolarizations during both inspiratory and expiratory phases, but it was interrupted by a transient repolarization between the last part of the inspiratory phase and the first part of the abdominal burst during which chloride-dependent inhibitory postsynaptic potentials were revealed. During swallowing, most CTMs hyperpolarized, and this hyperpolarization was sometimes followed by a weak depolarization. We conclude that the main role of the cricothyroid muscle is vocalization but the functional roles in coughing and swallowing are minor, and that the CTM activity during resting breathing and vocalization are primarily controlled by excitatory inputs, while during coughing and swallowing, inhibitory inputs play roles in shaping membrane potential trajectories. 相似文献
40.
Saijo Y Ohashi T Sasaki H Sato M Jorgensen CS Nitta S 《Annals of biomedical engineering》2001,29(12):1048-1053
Scanning acoustic microscopy (SAM) was equipped to assess the acoustic properties of normal and atherosclerotic coronary arteries. The SAM image in the atherosclerotic lesion clearly demonstrated that the sound speed was higher than that in the normal intima, and that the variation of elasticity was found within the fibrous cap of the plaque. Young's elastic modulus of each region was calculated and the finite element analysis was applied to derive the stress distribution in these arterial walls. In a case of normal coronary artery, the stress was dominant in the intima and the distribution was rather homogeneous and in a case of atherosclerosis, high stress was concentrated to the relatively soft lesion in the fibrous cap overlying lipid pool. SAM provides information on the physical properties, which cannot be obtained by the optical microscope. The results would help in understanding the pathological features of atherosclerosis. © 2001 Biomedical Engineering Society.
PAC01: 8764-t, 8763Df, 8719Xx, 8719Rr 相似文献