全文获取类型
收费全文 | 995篇 |
免费 | 73篇 |
国内免费 | 1篇 |
专业分类
儿科学 | 45篇 |
妇产科学 | 9篇 |
基础医学 | 124篇 |
口腔科学 | 40篇 |
临床医学 | 48篇 |
内科学 | 208篇 |
皮肤病学 | 29篇 |
神经病学 | 134篇 |
特种医学 | 16篇 |
外科学 | 149篇 |
综合类 | 8篇 |
预防医学 | 18篇 |
眼科学 | 4篇 |
药学 | 58篇 |
中国医学 | 5篇 |
肿瘤学 | 174篇 |
出版年
2023年 | 4篇 |
2022年 | 7篇 |
2021年 | 28篇 |
2020年 | 16篇 |
2019年 | 19篇 |
2018年 | 26篇 |
2017年 | 29篇 |
2016年 | 26篇 |
2015年 | 23篇 |
2014年 | 38篇 |
2013年 | 27篇 |
2012年 | 53篇 |
2011年 | 71篇 |
2010年 | 42篇 |
2009年 | 30篇 |
2008年 | 45篇 |
2007年 | 55篇 |
2006年 | 55篇 |
2005年 | 50篇 |
2004年 | 45篇 |
2003年 | 53篇 |
2002年 | 59篇 |
2001年 | 26篇 |
2000年 | 28篇 |
1999年 | 23篇 |
1998年 | 17篇 |
1997年 | 12篇 |
1996年 | 12篇 |
1995年 | 4篇 |
1994年 | 9篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 14篇 |
1990年 | 10篇 |
1989年 | 6篇 |
1988年 | 11篇 |
1987年 | 14篇 |
1986年 | 12篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1979年 | 2篇 |
1977年 | 2篇 |
1972年 | 3篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1966年 | 10篇 |
1965年 | 6篇 |
1961年 | 1篇 |
排序方式: 共有1069条查询结果,搜索用时 765 毫秒
1.
T Iino N Toyosaki T Katsuki T Noda T Natsume T Yaginuma S Hosoda M Furuse 《Clinical nuclear medicine》1987,12(9):688-693
The perfusion territories in polar representations of stress Tl-201 rotational myocardial imaging in patients with angina pectoris who had one diseased coronary segment were analyzed. The lesions proximal or distal to the first major septal perforator in left anterior descending arteries were detected by the presence or absence of defects at the base of the anterior septum. Right coronary artery lesions were detected by the presence of defects at the basal posterior septum, in contrast to the preservation of myocardial uptake at this portion in lesions of the left circumflex artery. The specific defect patterns were detected in cases with lesions at the first diagonal, obtuse marginal, and posterolateral branches. Recognition of these defects in the polar maps allows detailed detection of diseased coronary arterial branches. 相似文献
2.
Akihisa Okumura Ikuya Tsuge Tetsuo Kubota Hirokazu Kurahashi Jun Natsume Tamiko Negoro Kazuyoshi Watanabe 《European journal of paediatric neurology》2007,11(6):385-388
We evaluated drug-specific T cell responses in a patient with refractory partial seizures and paroxysmal kinesigenic choreoathetosis successfully treated with clinical desensitization to phenytoin. Drug-induced lymphocyte transformation test before desensitization was negative with a stimulation index of 130%. The frequencies and cytokine-producing phenotypes of phenytoin-specific T cells were examined simultaneously by using a carboxyfluorescein succinimidyl ester (CFSE) dilution assay. Before desensitization, the proportion of CFSElow CD4+ cells in whole CD4+ was 3.09%; 13.6% of CFSElow CD4+ cells were stained with anti-interferon gamma antibody. After desensitization, phenytoin-specific CFSElow CD4+ cells decreased to background level. These results indicate that CFSE dilution assay will be useful for the diagnosis and monitoring of drug hypersensitivity. 相似文献
3.
Yasuyuki Shimada Masatoshi Kawata Yasushi Iwasaki Hideshi Itoh Hideyuki Kawachi 《Annals of thoracic and cardiovascular surgery》2004,10(5):304-306
We operated on a patient who had been paraplegic since sustaining a spinal cord injury 11 years ago. We made a reversed L-shaped sternum incision and cannulated all tubes for the cardiopulmonary bypass through a wound window. This provided an excellent surgical view without restricting the patient's upper limbs (needed for wheel chair operation), and recovery was good. Just after surgery, however, it was difficult to control blood pressure and the loss of serum albumin. We believe this is the first report of open-heart surgery undertaken in a paraplegic patient and that the reversed L-shaped incision and careful monitoring of hemodynamics each played an important role in the successful outcome. We hope that this report will help in the treatment of other paraplegic patients who need open-heart surgery. 相似文献
4.
Hiroyoshi Suzuki Taisuke Otsuki Yuzo Iwasaki Ryuichi Katakura Hideshi Asano Mamoru Tadokoro Yoichi Suzuki Fumiaki Tezuka Hidehiro Takei 《Neuropathology》2002,22(1):40-47
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10). 相似文献
5.
Nicolas M. Bless Shinichiro J. Tojo Hiroko Kawarai Yasuhiro Natsume Alex B. Lentsch Vaishalee A. Padgaonkar Boris J. Czermak Hagen Schmal Hans P. Friedl Peter A. Ward 《The American journal of pathology》1998,153(4):1113-1122
Using two models of acute lung inflammatory injury in rats (intrapulmonary deposition of immunoglobulin G immune complexes and systemic activation of complement after infusion of purified cobra venom factor), we have analyzed the requirements and patterns for upregulation of lung vascular P-selectin. In the immune complex model, upregulation of P-selectin was defined by Northern and Western blot analysis of lung homogenates, by immunostaining of lung tissue, and by vascular fixation of 125I-labeled anti-P-selectin. P-selectin protein was detected by 1 hour (long before detection of mRNA) and expression was sustained for the next 7 hours, in striking contrast to the pattern of P-selectin expression in the cobra venom factor model, in which upregulation was very transient (within the 1st hour). In the immune complex model, injury and neutrophil accumulation were P-selectin dependent. Upregulation of P-selectin was dependent on an intact complement system, and the presence of blood neutrophils was susceptible to the antioxidant dimethyl sulfoxide and required C5a but not tumor necrosis factor α. In contrast, in the cobra venom factor model, upregulation of P-selectin, which is C5a dependent, was also dimethyl sulfoxide sensitive but neutrophil independent. Different mechanisms that may explain why upregulation of lung vascular P-selectin is either transient or sustained are discussed. 相似文献
6.
Influence of polymorphisms in the genes for cytokines and glutathione S-transferase omega on sporadic Alzheimer's disease 总被引:2,自引:0,他引:2
We studied promoter region polymorphisms in the interleukin (IL)-1alpha, IL-1beta, IL-6, IL-10, tumor necrosis factor, and transforming growth factor (TGF)-beta1 genes in Japanese patients with Alzheimer's disease (AD) (n = 172) and normal controls (n = 163). We also examined an association of a polymorphism located in the glutathione S-transferase omega 1 (GSTO-1) gene region with AD patients. None of these genotypes or allele frequencies showed a significant difference between AD patients and controls. We also failed to detect any difference in the disease onset between each genotype of the seven polymorphisms. Although AD patients carrying high producer alleles of TGF-beta1 and IL-1beta or TGF-beta1 and IL-6 showed a tendency for an early onset of the disease, neither of these combined effects reached a significant level after multiple comparisons. Our findings suggest that genetic polymorphisms in the cytokines and GSTO do not play a major role in Japanese AD patients. 相似文献
7.
Apoptosis-inducing protein derived from hepatocyte selectively induces apoptosis in lymphocytes 总被引:2,自引:0,他引:2
The liver is where lymphocytes undergo activation-induced cell death (AICD) at the resolution phase of an immune response, which is crucial for homeostasis of the immune system and prevention of autoimmunity. Exploring the machinery of AICD in the liver, we found that a primary culture supernatant of murine hepatocytes had an antiproliferative effect on antigen-stimulated T clone and T lymphoma cells. Biological study showed that the antiproliferation was due to induction of apoptosis in a caspase-dependent manner. The apoptosis-inducing potential was sensitive to trypsin, heat (> 70 degrees ) and acid (< pH 5) treatment but could not be neutralized by anti-tumour necrosis factor-alpha, anti-Fas ligand, or anti-transforming growth factor-beta antibodies. Biochemical study of the isolated and purified apoptosis-inducing component from the supernatant showed that it was a protein with a molecular mass of about 68,000-70,000. It induced apoptotic change in murine T and B cells, and to a lesser degree, in human lymphoid cells, but not in macrophages. Biochemical and biological characteristics distinguish this protein from others that have been reported to induce apoptosis of lymphocytes. The identification of an apoptosis-inducing protein derived from murine hepatocytes, which selectively induces apoptosis in lymphocytes, suggests one possible mechanism for immune suppression in the liver. 相似文献
8.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology》1993,67(4):354-359
Summary We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
9.
The effect of alpha-adrenergic agents on theta-like activity (TLA) in guinea-pig hippocampal slices was studied. TLA was induced by a cholinergic agent, carbachol. TLA had a frequency of 4.66+/-0.08 Hz (mean+/-S.E.M.) and an amplitude of 96.3+/-8.3 microV in the dentate gyrus (DG). The alpha-adrenergic agents epinephrine and clonidine increased the frequency and decreased the amplitude of TLA in a concentration-dependent manner. The agents also increased antidromic and orthodromic population spike (PS) amplitudes of the granule cells, but did not have any effect on population EPSP. Another alpha-adrenergic agent, guanabentz, had the same effect as clonidine. The adenylate cyclase inhibitor SQ22536 suppressed the increase in PS amplitude by clonidine. The results suggest that these alpha2-adrenergic agents facilitate the activity of granule cells through the activation of the alpha2-adrenoreceptor and cAMP pathway, and the facilitation causes the desynchronization of TLA. 相似文献
10.
In the present study, 93 cells in the superior colliculus (SC) were recorded extracellularly during the simultaneous occurrence of spontaneous theta field activity, sensory-induced (tail pinch) theta field activity, and large amplitude irregular (LIA) field activity, recorded from an electrode located in the stratum moleculare of the hippocampal formation (HPC). The effect of the intravenous administration of atropine sulfate (ATSO4) was also tested on SC cellular activity. The field activities of theta and LIA were recorded from all layers of the SC and were found to be temporally coherent with the same activities recorded simultaneously from the HPC, during all conditions tested. By using the criteria of Colom and Bland (1987) for the classification of theta-related cells, 75 of 93 cells (81%) were found to be related to the generation of theta field activity in the HPC and 18 of 93 (19%) were nonrelated. All cells recorded discharged in a tonic, nonrhythmic pattern during the theta HPC field states. Of the 75 theta-related cells, 61 (81%) were classified as tonic theta-ON cells and 14 (19%) as tonic theta-OFF cells. Although these cell types were found in all three layers of the SC, the majority of tonic theta-ON cells were recorded in the intermediate layer, and the tonic theta-OFF cells were dispersed evenly between the intermediate layer and the deep layer of the SC. The intravenous administration of ATSO4 abolished theta field activity in the HPC and SC, and the theta-related increase in the discharge rate of all tonic theta-ON cells tested. However, the same treatment did not have any effect on the discharge properties of tonic theta-OFF cells. The same stimuli that resulted in the inhibition of the discharge rates of these cells (tail pinch and electrical stimulation of the PH) in the predrug condition did so after the administration of ATSO4. 相似文献