首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   354篇
  免费   2篇
耳鼻咽喉   6篇
儿科学   15篇
妇产科学   4篇
基础医学   126篇
口腔科学   2篇
临床医学   51篇
内科学   28篇
皮肤病学   1篇
神经病学   11篇
特种医学   8篇
外科学   31篇
预防医学   24篇
药学   33篇
肿瘤学   16篇
  2022年   4篇
  2021年   5篇
  2016年   3篇
  2015年   3篇
  2013年   8篇
  2011年   8篇
  2010年   7篇
  2009年   6篇
  2008年   13篇
  2007年   12篇
  2006年   11篇
  2005年   5篇
  2004年   6篇
  2003年   4篇
  2002年   8篇
  2001年   7篇
  2000年   11篇
  1999年   11篇
  1993年   6篇
  1992年   12篇
  1991年   6篇
  1990年   14篇
  1989年   11篇
  1988年   13篇
  1987年   9篇
  1986年   13篇
  1985年   15篇
  1984年   7篇
  1983年   4篇
  1982年   7篇
  1981年   3篇
  1979年   7篇
  1978年   7篇
  1976年   6篇
  1975年   5篇
  1974年   9篇
  1973年   9篇
  1972年   5篇
  1971年   5篇
  1970年   4篇
  1969年   3篇
  1968年   7篇
  1967年   3篇
  1966年   2篇
  1965年   7篇
  1964年   2篇
  1961年   2篇
  1958年   2篇
  1957年   2篇
  1956年   2篇
排序方式: 共有356条查询结果,搜索用时 31 毫秒
1.
2.
Soluble antigen HLA-B27 was assayed in blood serum of 30 patients afflicted with ankylosing spondyloarthritis (AS) and 25 healthy subjects having HLA-B27 (B27+) antigen in the phenotype. As compared to B27+ healthy subjects, B27+ patients with AS demonstrated a significantly higher level of soluble HLA-B27 antigen. A substance whose functional activity was found to be identical to that of soluble HLA-B27 antigen in blood serum of B27- patients with AS was discovered for the first time. It was absent from B27- healthy subjects. In addition to the identification of the fixed forms of soluble HLA-B27 antigen, the assay of this antigen in blood serum enhances the potentialities of laboratory diagnosis of AS, which plays an important role at the early disease stages.  相似文献   
3.
Mechanical or thermal injury to one of a pair of parabiotic rats with a crossed circulation but separate innervation was followed by the development of a state resembling shock in the other partner. Microcirculatory changes characteristic of either traumatic or burn shock developed in its mesentery under these circumstances. The results are interpreted as evidence in support of a humoral rather than a nervous mechanism of the microcirculatory disturbances in these types of shock.Laboratory of Pathophysiology of Extremal States, Research Institute of General Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 10, pp. 416–418, October, 1978.  相似文献   
4.
Neurosurgical procedures can result in brain injury by various means including direct trauma, hemorrhage, retractor stretch, and electrocautery. This surgically-induced brain injury (SBI) can cause post-operative complications such as brain edema. By creating a mouse model of SBI, we tested whether NADPH oxidase, an important reactive oxygen species producing enzyme, is involved in SBI using transgenic mice lacking gp91phox subunit of NADPH oxidase (gp91phox KO) and apocynin, a specific inhibitor of NADPH oxidase. Neurological function and brain edema were evaluated at 24 h post-SBI in gp91phox KO and wild-type littermates grouped into SBI and sham-surgery groups. Alternatively, mice were grouped into vehicle- and apocynin-treated (5 mg/kg, i.p. 30 min before SBI) groups. Oxidative stress indicated by lipid peroxidation (LPO) was measured at 3 and 24 h post-SBI. The gp91phox KO mice, but not the apocynin-treated mice showed significantly improved neurological scores. Brain edema was observed in both gp91phox KO and wild-type groups after SBI; however, there was no significant difference between these two groups. Brain edema was also not affected by apocynin-pretreatment. LPO levels were significantly higher in SBI group in both gp91phox KO and wild-type groups as compared to sham group. A trend, although without statistical significance, was noted towards attenuation of LPO in the gp91phox KO animals as compared to wild-type group. LPO levels were significantly attenuated at 3 h post-SBI by apocynin-pretreatment but not at 24 h post-SBI. These results suggest that chronic and acute inhibition of NADPH oxidase activity does not reduce brain edema after SBI. Long-term inhibition of NADPH oxidase, however improves neurological functions after SBI.  相似文献   
5.
6.
BACKGROUND AND PURPOSE: Aortic arch atheromas (AAs) have been shown to be a risk factor for ischemic stroke (IS) in the elderly because of their potential for cerebral embolization. However, the association between AAs and the presence of cerebral microemboli has not been clearly established. The aim of this study was to determine whether large AAs are associated with an increased frequency of high-intensity transient signals (HITS) in elderly patients with IS. METHODS: We performed bitemporal simultaneous HITS monitoring of both middle cerebral arteries in 62 consecutive elderly patients with acute IS (mean age 72.5+/-8.8 years, 65% men). In 16 patients, one or both temporal windows were inadequate; therefore, the analysis of HITS was performed in the remaining 46 patients. All patients underwent omniplane transesophageal echocardiography (TEE), and they had no significant extracranial or intracranial artery disease and no cardiac prosthetic valves. Large AA was defined as > or = 4 mm in thickness. Complex AA was defined as ulcerated or mobile, regardless of plaque thickness. HITS monitoring was performed within 24 hours of TEE and analyzed by an experienced neurologist-sonographer blinded to TEE findings. A 9-dB threshold was chosen to discriminate HITS from background Doppler signal. The HITS counts in the left and in the right middle cerebral arteries were added and reported as a total number of HITS in 30 minutes. RESULTS: HITS were detected in 14 (78%) of 18 patients with large AAs versus 8 (29%) of 28 patients with no or small AAs (odds ratio [OR] 8.8, 95% CI 2.2 to 34.8; P=0. 001). The association was also present in 27 patients with no other cardiac embolic sources, such as atrial fibrillation, patent foramen ovale, spontaneous echo contrast, and thrombus (7 of 10 patients with large AAs versus 3 of 17 patients with small or no AA; OR 10.9, 95% CI 1.7 to 68.5; P=0.013). Complex AAs were associated with a higher frequency of HITS than were noncomplex AAs (6 of 6 patients with complex AAs versus 15 of 39 patients with noncomplex AAs; OR 2. 6, 95% CI 1.7 to 3.9; P=0.005). CONCLUSIONS: HITS are significantly associated with large AAs in elderly stroke patients. This observation may support the causal role of large AAs in IS.  相似文献   
7.
As a result of the conducted experimental studies on intranasal challenge of ICR mice, rabbits and miniature pigs (even in the maximum variant) with the doses of 4.0–5.5 lg PFU of monkeypox virus (MPXV), some clinical signs such as purulent conjunctivitis, blepharitis and ruffled fur were found only in mice. The 50% infective dose (CID50) of MPXV for these animals estimated by the presence of external clinical signs was 4.8 lg PFU, and LID50 estimated by the virus presence in the lungs of mice 7 days post‐infection taking into account its 10% application in the animal respiratory tract was 1.4 lg PFU. When studying the dynamics of MPXV propagation in mice challenged intranasally with 25 LID50 of MPXV, the maximum pathogen accumulation was revealed in nasal cavity, lungs and brain: 5.7 ± 0.1, 5.5 ± 0.1 and 5.3 ± 0.3 lg PFU/ml, respectively. The pathomorphological examination of these animals revealed the presence and replication of the pathogen in the traditional primary target cells for MPXV (mononuclear phagocyte system cells and respiratory tract epitheliocytes) as well as in some other types of cells (endothelial cells, reticular cells, connective tissue cells). Our use of these animals to assess the antiviral efficacy of some drugs demonstrated the agreement of the results (a significant positive effect of NIOCH‐14 and ST‐246) with those described in scientific literature, which opens up the prospects of using ICR mice as animal models for monkeypox to develop preventive antismallpox drugs.  相似文献   
8.
9.
Effect of mesodiencephalic modulation on small intestinal mucosa was studied in rats subjected to massive blood loss. Massive blood loss induced structural changes in intestinal epitheliocytes typical of tissue hypoxia: intraintestinal edema, mitochondrial alterations, and microcirculation disturbances. A single session of mesodiencephalic stimulation carried out 60 min after massive blood loss produced a pronounced adaptive effect, restored disturbed structure of the intestinal villi, and induced compensatory hypertrophy of the mitochondria. This suggests that mesodiencephalic modulation promotes normalization of intracellular energy metabolism, improves the absorption capacity of bordered enterocytes, and restores the disturbed intestinal barrier.  相似文献   
10.
Physico-chemical and medico-biological methods, including hematology and cytology, were used in an evaluation of properties of poly(2-hydroxyethyl methacrylate) (poly(HEMA))-based embolic material indicated in the occlusion of branches of hepatic artery of patients with focal alterations of the liver. The elastographic method helped in predicting mechanical properties of the hydrogel material. Poly(HEMA) was mechanically stable for endovascular applications, exhibited no significant loss in elasticity and possessed consistency resembling the soft tissue of the organism. Analysis of blood in contact with poly(HEMA) hydrogel provided a control of its biological inertness. Recently, 315 patients with focal alterations of the liver, including hemobilic hemorrhages and both primary and metastatic tumors, underwent endovascular occlusion with poly(HEMA) emboli as a pre-surgical step or as a simple occlusive measure. Compared with a direct operation on hemangiomatous injuries in the liver without endovascular occlusion, embolization with poly(HEMA) allowed to reduce 2.5-3 times bleeding in the operational zone. At the same time, the poly(HEMA) embolic material induced activation of general hemostatic reaction in the postembolization period.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号