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131.
Key words dysrhythmia - isorhythmic dissociation - oscillation 相似文献
132.
Ginsenoside Ro, an oleanane-type saponin has been screened for activity in experimental models of inflammation. Ginsenoside Ro (10,50, and 200 mg/kg, P. O.) inhibited an increase in vascular permeability in mice induced by acetic acid and reduced an acute paw edema in rats induced by compound 48/80 or carrageenin. Ginsenoside Ro did not suppress a developing adjuvant-induced edema in arthritic rats. However, ginsenoside Ro was found to be effective in hypercoagulable state, increase of connective tissue in the artery and calcium effluence from the bone in adjuvant-induced arthritic rats. 相似文献
133.
Great horovement haS been made in the cryopreservation Of inalnlnalian elnbmp since wnttingham['] reported his Pioneering wold about successful cryOPreservationof mouse embryo. It results in the availability of cryOPreserVation of embryos of all stages[']. HOwever, cryopreserved embryos can not avoid the damages by ice crystal,which is a major cause of cen death in the freezing andthawing ProceduresL',']. SO it is necesseq to seareh for anew and more efficient method for embryO cryOPrese… 相似文献
134.
Masahiko Igarashi Yuki Takeda Seijiro Mori Naoko Ishibashi Eiichi Komatsu Kentaro Takahashi Tsunekazu Fuse Mikako Yamamura Kazuki Kubo Yasuo Sugiyama Yasushi Saito 《British journal of pharmacology》1997,120(6):1172-1178
- The aim of this study was to determine whether BAYw6228 (BAYw), a newly developed 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, could suppress an atherogenic process such as intimal thickening by a mechanism other than lowering the level of serum cholesterol.
- First, we evaluated the in vitro effect of BAYw on the proliferation of vascular smooth muscle cells (SMC) from various species: Sprague-Dawley (SD) rats, New Zealand (NZ) white rabbits, intimal cells from Watanabe hereditary hyperlipidemic (WHHL) rabbit and SMC from the new-born human aorta. The increasing rate of total protein content of these cells was inhibited by the addition of BAYw in a dose-dependent fashion. In the presence of 2% foetal calf serum (FCS), the value of IC50 was 1.0 μM in SD rats. 2.1 μM in NZ white rabbits, and 0.3 μM in WHHL rabbits. With human SMC, the value was 0.02 μM in the presence of 10% FCS and 0.2 μM with a mixture of growth factors.
- Based on these above in vitro findings, we next examined the in vivo effect of the agent to determine whether it could suppress rabbit intimal thickening induced by balloon catheterization. A balloon catheter was inserted from a peripheral branch of the left external carotid artery to the aorta to denude the endothelium of the left common carotid artery in Japanese white rabbits. After 12 days they were divided into control and BAYw groups. The former were subcutaneously injected with saline and the latter with BAYw 1 mg kg−1 day−1. Two days after the beginning of treatment, a second balloon injury was performed to the previously injured left common carotid artery in both groups. After another two weeks, the left common carotid artery was removed and variously stained. Although the total serum cholesterol in the BAYw group was significantly lower than in the control (P<0.05), the difference was not enough to affect intimal thickening. In addition, the BAYw group had a smaller intima/media ratio than the control group, decreasing to 45% of control (P<0.05). By anti-α smooth muscle actin antibody staining, these intimal thickening areas were entirely occupied by SMCs, and their amount was attenuated by BAYw. By anti-rabbit macrophage antibody (RAM 11) staining, the number of positive cells in the intimal thickening was markedly decreased in the BAYw group compared to control (P<0.01).
- These results indicate that BAYw has an inhibitory effect on intimal thickening by attenuating intimal SMC proliferation and infiltration of macrophages, suggesting that BAYw could be effective in the prevention of the progression of atherosclerotic plaque-like restenosis after angioplasty.
135.
Shuji Kaneko Nobumichi Yada Koichiro Fukuda Masanobu Kikuwaka Akinori Akaike Masamichi Satoh 《British journal of pharmacology》1997,121(4):806-812
- Desensitization of μ- and κ-opioid receptor-mediated inhibition of voltage-dependent Ca2+ channels was studied in a Xenopus oocyte translation system.
- In the oocytes coexpressing κ-opioid receptors with N- or Q-type Ca2+ channel α1 and β subunits, the κ-agonist, U50488H, inhibited both neuronal Ca2+ channel current responses in a pertussis toxin-sensitive manner and the inhibition was reduced by prolonged agonist exposure.
- More than 10 min was required to halve the inhibition of Q-type channels by the κ-agonist. However, the half-life for the inhibition of N-type channels was only 6±1 min. In addition, in the oocytes coexpressing μ-opioid receptors with N-type or Q-type channels, the uncoupling rate of the μ-receptor-mediated inhibition of N-channels was also faster than that of Q-type channels.
- In the oocytes coexpressing both μ- and κ-receptors with N-type channels, stimulation of either receptor resulted in a cross-desensitization of the subsequent response to the other agonist. Treatment of oocytes with either H-8 (100 μM), staurosporine (400 nM), okadaic acid (200 nM), phorbol myristate acetate (5 nM) or forskolin (50 μM) plus phosphodiesterase inhibitor did not affect either the desensitization or the agonist-evoked inhibition of Ca2+ channels.
- These results suggest that the rate of rapid desensitization is dependent on the α1 subtype of the neuronal Ca2+ channel, and that a common phosphorylation-independent mechanism underlies the heterologous desensitization between opioid receptor subtypes.
136.
Ohno A Hirashima T Kubo A Masuda N Takada M Fujiwara H Yasumitsu T Kikui M Fukuoka M Nakagawa K 《International journal of oncology》1997,10(3):521-528
To investigate the role of p53 abnormalities in predicting the survival of patients with non-small cell lung cancer (NSCLC), polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and immunohistochemical analyses were performed on 74 and 67 tumor samples, respectively, from patients with pathological stage I-IIIa NSCLC. An abnormally migrating SSCP band was observed in 21 of 74 (28%) tumor specimens. DNA sequence analysis revealed 23 intragenic mutations including 3 small deletions and 20 point mutations. Immunohistochemical analysis using the DO-7 monoclonal antibody showed abnormal expression of p53 in 27 of 67 (40%) patients. The concordance rate between immunohistochemical and PCRSSCP analyses was 73% (49/67) in this study. Univariate and multivariate analyses demonstrated that abnormal expression of p53 may be associated with prolonged survival (p=0.0997 and 0.0099, respectively). In contrast, no relationship was observed between p53 mutation and overall survival (0.6968). These results suggest that p53 status and the survival outcome changes between immunohistochemical and mutational analyses in stage I-IIIa NSCLC. 相似文献
137.
We evaluated three solutions used for preserving lungs, namely, University of Wisconsin (UW), Euro-Collins (E-C), and low potassium dextran (LPD), by measuring the high energy phosphates in the preserved lung tissue. The left lungs of Sprague-Dawley rats were excised and flushed with 5 ml of one of the solutions at 10°C through the pulmonary artery, after which they were deflated and immersed in the solution at 10°C for 24 h. The tissue adenosine triphosphate (ATP) concentration in mol/g tissue wet weight after 24 h of storage was 2.55 ± 0.48 (n = 7) in the UW lungs, 1.98 ± 0.25 (n = 6) in the E-C lungs, and 1.53 ± 0.32 (n = 4) in the LPD lungs, being significantly higher in the UW lungs than in either the E-C or LPD lungs (P < 0.05). The histopathological findings of the E-C lungs were more deteriorated, with marked interstitial edema, septal hypertrophy, and perivascular hyaline degeneration, than either the UW or LPD lungs. Thus, the findings of this study indicate the superiority of UW solution for lung preservation. 相似文献
138.
Tomoaki Fujioka Koich Ishikura Michihiko Hasegawa Kazunori Ogyu Yasushi Matsushita Masatsugu Sato Fumio Sato Hikaru Aoki Takashi Kubo 《Cancer chemotherapy and pharmacology》1995,36(1):7-12
Bropirimine [2-amino-5-bromo-6-phenyl-4-(3H)-pyrimidinone] is a low-molecular-weight compound that acts as an inducer of interferon in several animal species. Experiments were designed to explore the possibility of using this drug for the treatment of renal-cell carcinoma (RCC). Euthymic BALB/c mice were inoculated with murine RCC (Renca) cells and given graded doses of Bropirimine p.o. for 5 consecutive days beginning on day 1 following tumor inoculation. These mice were killed and tumors were excised on day 21. Bropirimine significantly (P<0.01) inhibited the tumor growth at a daily dose of 1,000 or 2,000 mg/kg. No adverse effect or toxicity was noted at 1,000 mg/kg, and at 2,000 mg/kg there was only a marginal body-weight reduction without any other appreciable side effect. In addition to the inhibition of tumor growth, there was a small yet significant (P<0.05) increase in the duration of survival (in days) in the Bropirimine-treated animals. When the treatment was delayed to begin on day 6 following tumor inoculation, Bropirimine did not suppress tumor growth in euthymic mice, pointing to the importance of the timing of the treatment. In athymic nude BALB/c mice lacking T-cells or T-cell function, Bropirimine also inhibited tumor growth (P<0.01). The antitumor effect of this drug was abolished by pretreatment with anti-asialo GM1 serum, which eliminated natural killer (NK) activity in euthymic mice. In vivo treatment with Bropirimine augmented the cytotoxicity of lymphocytes isolated from the spleens or lungs of the tumor-bearing mice, which were active against Renca and YAC-1 cells in vitro. This activity was NK-cell-dependent as judged on the basis of the results of the in vitro complement-dependent cytotoxicity assay. Since Bropirimine induced interferon (IFN)-/ production, significantly (P<0.05) elevating its serum concentration, and since this drug mimics the effects of IFN-/, it seemed likely that the Bropirimine-induced NK cell augmentation we found was mediated by IFN-/. These results suggest that Bropirimine, a booster of NK activity, may have potential as an adjunct to other therapeutic modalities in the treatment of human RCC. 相似文献
139.
The basement membrane (BM), a structure of crucial importance in the invasion and metastasis of cancers, was studied immunohistochemically using colorectal cancer tissues. In addition, BM-like structures formed in the primary culture of cancer cells were compared to the BM of primary cancers. BM was stained with antibodies specific for laminin, type IV collagen, fibronectin, and heparan sulfate proteoglycan. In the normal colon these compounds were detected in the glandular BM, vascular BM and perinervium by immunostaining. Components of the BM were not stained in some cancer tissues, and BM staining essentially disappeared in the invasive front of cancer in several cases. Of whole cancer tissues, 10 of 23 cases (43.5%) were BM positive and the remaining 13 cases (56.5%) were negative. A three dimensional primary culture of colorectal cancer cells was performed in collagen gel. The cancer cells obtained from primary cancers which had densely stained for BM formed a BM-like structure in primary culture, but those from negatively stained cancer tissues showed no BM-like structures. The BM-like structure in the primary culture was shown to have the same components as the true BM by immunohistochemistry, and this membranous structure was shown to have originated in the cancer cells. In the primary culture without any BM-like structures, granules containing BM components were observed around tumor cell clusters. The primary culture of tumor cells in collagen gel is closely related to the original tumor tissues and therefore may provide a good model system for the investigation of BM in cancer. 相似文献
140.
Marked Suppression of T Cells by a Benzothiophene
Derivative in Patients with Human T-Lymphotropic Virus Type
I-Associated Myelopathy/Tropical Spastic Paraparesis
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Masahiko Makino Miyuki Azuma Shin-Ichi Wakamatsu Yukio Suruga Shuji Izumo Mitchel M. Yokoyama Masanori Baba 《Clinical and Vaccine Immunology : CVI》1999,6(3):316-322
In a search for new anti-autoimmune agents that selectively
suppress activation of autoreactive T cells, one such agent,
5-methyl-3-(1-methylethoxy)benzo[b]thiophene-2-carboxamide
(CI-959-A), was found to be effective. This compound, which is known to
suppress tumor necrosis factor alpha (TNF-α)-induced CD54 expression,
inhibited the primary proliferative response of the T cell to antigen
(Ag)-presenting cells (APCs) including allogenic dendritic cells (DCs),
autologous Epstein-Barr virus-infected B cells, and human T
lymphotropic virus type I (HTLV-I)-infected T cells. Autoreactive T
cells from patients with HTLV-I-associated myelopathy/tropical spastic
paraparesis (HAM/TSP) spontaneously proliferate in vitro, and their
activation is reported to be associated with CD54 expression. The
spontaneous proliferation of T cells from patients with HAM/TSP was
entirely blocked by CI-959-A. However, in this study, the T-cell
proliferation in 15 patients with HAM/TSP was found to depend more
extensively on major histocompatibility complex (MHC) class II and CD86
than on CD54 Ags. Since most important APCs for the development of
HAM/TSP are DCs and HTLV-I-infected T cells, the effect of CI-959-A on
DC generation and on the expression of surface molecules on activated T
cells is examined. CI-959-A suppressed recombinant
granulocyte-macrophage colony stimulating factor (GM-CSF)- and
recombinant interleukin-4-dependent differentiation of DCs from
monocytes and inhibited the expression of CD54 and, more extensively,
MHC class II and CD86 Ags. CI-959-A showed little toxicity toward
lymphoma or HTLV-I-infected T-cell lines or toward monocytes and
cultured DCs. These results suggest that CI-959-A might be a potent
anti-HAM/TSP agent.Human T lymphotropic virus type I
(HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP)
is thought to be an autoimmune disease induced by HTLV-I infection
(8, 9, 24). The T lymphocytes obtained from patients with
HAM/TSP patients produce interleukin-2 (IL-2) in vivo and proliferate
spontaneously in vitro without any additional stimuli or cytokines
(35). This spontaneous proliferation of T lymphocytes (SPL)
depends on the interaction of T cells with antigen (Ag)-presenting
cells (APCs) such as dendritic cells (DCs) (17, 25) and
HTLV-I-infected CD4+ T cells (15, 32). The DCs
localized in the blood and nonlymphoid organs are considered to be
functionally immature, in that they are optimized for the uptake and
processing of Ag but not for the initiation of primary T-cell
responses. However, after the uptake of Ag and exposure to inflammatory
agents including tumor necrosis factor alpha (TNF-α) and IL-1, the
DCs undergo a process of maturation and gain the ability to present Ag
to T cells for their priming (22, 26). In addition to DCs,
HTLV-I-infected CD4+ T cells directly stimulate autologous
CD4+ T cells in a major histocompatibility complex (MHC)
class II- and CD86 molecule-dependent fashion (32). Among
the T cells stimulated with these APCs, some might cross-react with
self Ags and closely associate with the development of HAM/TSP.We have been searching for compounds that inhibit the cellular
interaction between APCs and T cells to suppress the activation of
autoreactive and Ag-specific T cells. The molecules associated with the
APC-T cell interaction may provide an effective target for therapy for
autoimmune diseases. Binding of APCs and T cells is initiated by
contact of adhesion molecules, such as CD54 and CD11a/CD18, expressed
on both cells, and induction of sustained proliferation of T cells
requires two independent signals provided by APCs: a T-cell
receptor-mediated Ag-specific signal and a signal mediated by
costimulatory molecules (CSMs) (10, 20) including CD86 and
CD58 Ags (1, 11, 31). Blocking of their tight binding
through adhesion molecules or interaction of the CSMs with CSM ligands
effectively suppressed the abnormal expansion of disease-associated T
cells in vivo and in vitro (19, 30, 32) and sometimes
effectively induced a long-term unresponsiveness of T cells to recall
stimuli.5-Methyl-3-(1-methylethoxy)benzo[b]thiophene-2-carbox-amide
(CI-959-A) is known to inhibit CD54 expression, and its derivative is
reported to inhibit casein kinase II (4). In the present
study, we found that CI-959-A markedly suppressed SPL in patients with
HAM/TSP. Furthermore, the compound suppressed the primary T-cell
proliferative response to stimuli provided by various APCs, the
differentiation of immature DCs from monocytes and their subsequent
maturation, and the induction of expression of MHC class II, CD54, and
CD86 Ags on activated CD4+ T cells. 相似文献