全文获取类型
收费全文 | 142篇 |
免费 | 4篇 |
国内免费 | 12篇 |
专业分类
儿科学 | 10篇 |
妇产科学 | 1篇 |
基础医学 | 14篇 |
口腔科学 | 2篇 |
临床医学 | 19篇 |
内科学 | 18篇 |
皮肤病学 | 1篇 |
神经病学 | 1篇 |
特种医学 | 51篇 |
外科学 | 5篇 |
综合类 | 17篇 |
预防医学 | 6篇 |
眼科学 | 2篇 |
药学 | 7篇 |
肿瘤学 | 4篇 |
出版年
2021年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 3篇 |
2014年 | 1篇 |
2013年 | 6篇 |
2012年 | 5篇 |
2010年 | 4篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 7篇 |
2006年 | 7篇 |
2005年 | 11篇 |
2004年 | 1篇 |
2002年 | 1篇 |
2001年 | 3篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 4篇 |
1993年 | 9篇 |
1992年 | 4篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1971年 | 1篇 |
1964年 | 2篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1961年 | 3篇 |
排序方式: 共有158条查询结果,搜索用时 15 毫秒
81.
M Andersson A Usiello A Borgkvist L Pozzi C Dominguez AA Fienberg P Svenningsson BB Fredholm E Borrelli P Greengard G Fisone 《The Journal of neuroscience》2005,25(37):8432-8438
Herbal cannabis, smoked in the form of marihuana or hashish, is the most common illicit drug consumed in the Western world. In the brain, cannabinoids interact with neuronal CB1 receptors, thereby producing a marked reduction of motor activity. Here, we report that the motor depressant effect produced by the cannabinoid receptor agonist (-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]trans-4-(3-hydroxypropyl)cyclohexanol (CP55,940) is attenuated by genetic inactivation of the dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32), which is abundantly expressed in the medium spiny neurons of the striatum. Point mutation of Thr34, the protein kinase A (PKA) phosphorylation site of DARPP-32, produces a similar reduction in the effect of the CB1 agonist. In contrast, point mutation of Thr75, a site on DARPP-32 specifically phosphorylated by cyclin-dependent kinase 5, does not affect the behavioral response to CP55,940. Activation of CB1 receptors, either by an agonist or by inhibition of reuptake of endogenous cannabinoids, stimulates phosphorylation at Thr34, thereby converting DARPP-32 into an inhibitor of protein phosphatase-1. Genetic inactivation either of dopamine D2 receptors or of adenosine A2A receptors reduces the phosphorylation of DARPP-32 at Thr34 and the motor depression produced by CP55,940. Our data indicate that a considerable proportion of the psychomotor effect of cannabinoids can be accounted for by a signaling cascade in striatal projection neurons involving PKA-dependent phosphorylation of DARPP-32, achieved via modulation of dopamine D2 and adenosine A2A transmission. 相似文献
82.
83.
Late-onset rheumatoid arthritis: is pitting oedema of the hands at onset a good prognostic indicator? 总被引:1,自引:0,他引:1
This prospective study compares the clinical and radiological outcome of
patients with late-onset (age 65 yr and over) rheumatoid arthritis (RA)
presenting with and without pitting oedema of the hands (POH). Twenty-two
patients with POH (Group 1) were compared with 81 (Group 2) without POH
(median age of onset of RA-Group 1: 74.3; Group 2: 73.1; female to male.
ratio-Group 1: 1.2:1; Group 2: 2.5:1). The median time between the onset of
arthritis and baseline assessment was 3 months. Minimum follow-up was 1 yr
(median 2.4). Outcome was defined by (1) the development of erosions of the
hands, wrists or feet and (2) the number of patients in remission
(clinically inactive disease on two clinic visits 3 months apart with no
intervening history of inflammatory joint disease). IgM rheumatoid factor
(IgM RF) was less frequent in patients with POH (Group 1:8.2%; Group 2:
43.2%, P < or = 0.05). Logistic regression analysis showed that POH at
onset was independent of IgM RF in determining outcome. Patients with POH
were less likely to develop erosions [odds ratio (OR) = 0.16, 95%
confidence interval (CI) 0.03, 0.89]. Although initial cross-tabulation
suggested an increased frequency of remission in Group 1 (Group 1: 90.9%;
Group 2: 55.5%, P = 0.02), POH was not found to be a significant predictor
using the logistic regression model (OR = 7.42, 95% CI 0.84, 65.7).
Patients with IgM RF were more likely to develop erosions (OR = 5.1, 95% CI
1.46, 17.67) and less likely to go into remission (OR = 0.19, 95% CI 0.06,
0.68).
相似文献
84.
微波治疗宫颈糜烂50例 总被引:9,自引:0,他引:9
1 临床资料宫颈糜烂患者50例,年龄22 ~50岁. 盆腔检查正常,无阴道炎症,宫颈细胞学涂片无癌细胞. 糜烂面积小于宫颈总面积的1/3为轻度糜烂10例, 1/3~2/3为中度35例,2/3以上为重度5例. 其中合并宫颈直径3.0~3.5 cm为Ⅰ度宫颈肥大4例,宫颈直径3.5~4.0 cm为Ⅱ度6例,宫颈直径>4 cm为Ⅲ度2例. 治疗使用微波治疗仪微波输出功率30~40 W,操作时间2~6 s. 选月经干净后3~5 d取膀胱截石位,常规消毒外阴、阴道、宫颈,用窥阴器充分暴露宫颈,再次用无菌干棉球擦净宫颈分泌物,以免黏液形成假结痂,影响治疗深度. 相似文献
85.
86.
Four patients with 5 nonopaque renal calculi composed of uric acid were examined by ultrasound. The calculi varied in size from a 1.5 X 1.5-cm intrapelvic stone to a staghorn calculus measuring 4 cm. All stones were satisfactorily imaged by ultrasound, allowing a diagnosis of nephrolithiasis to be made with confidence in each case. In 2 patients with poor excretion on urography, the diagnosis was not suspected prior to the ultrasound examination. The authors feel that ultrasound has great potential value in the investigation of nonopaque filling defects of the renal pelvis and in patients with urographic nonvisualization who have a high risk of uric acid lithiasis. 相似文献
87.
Intrahepatic amebic abscesses: indications for and results of percutaneous catheter drainage 总被引:2,自引:0,他引:2
vanSonnenberg E; Mueller PR; Schiffman HR; Ferrucci JT Jr; Casola G; Simeone JF; Cabrera OA; Gosink BB 《Radiology》1985,156(3):631-635
Medical therapy is standard for intrahepatic amebic abscess and generally is effective. However, we have encountered a group of patients in whom percutaneous aspiration and drainage was indicated due to uncertainty of diagnosis or clinical deterioration of the patient. Twenty such patients underwent percutaneous drainage with ultrasound or CT guidance, and each patient was cured (appropriate antibiotics were administered concomitantly). The specific indications for intervention were to differentiate pyogenic from amebic abscess, pain and imminent rupture, poor response to medical therapy, false-negative results of serologic tests, noncompliance with medical treatment, left lobe abscess, and pregnancy. Diagnosis of amebiasis from examination of the fluid was seldom possible, while findings from core biopsy of the wall of the abscess led to diagnosis in three cases. Recurrence necessitating redrainage occurred in three patients; in each, catheters were removed the same day drainage was performed. There were three minor complications. Differences from percutaneous management of pyogenic abscesses included more rapid removal of catheters (four days), more frequent use of US guidance, and more common use of the prone angled approach to avoid pleural contamination. Catheter drainage may be curative and may expedite care for problematic amebic liver abscesses in selected cases. 相似文献
88.
89.
90.
N'-(3'-Monophospho-deoxyguanosin-8-yl)-N-acetylbenzidine (dGp-ABZ) is
thought to play an important role in initiation of benzidine-induced
bladder cancer in humans. This report assesses the possible formation of
this adduct by peroxidatic activation of N-acetylbenzidine (ABZ). Adduct
formation was measured by 32P-post-labeling. Ram seminal vesicle microsomes
were used as a source of prostaglandin H synthase (PHS). The peroxidatic
activity of PHS was compared with that for horseradish peroxidase. Both
peroxidases converted ABZ to dGp-ABZ whether DNA or 2'- deoxyguanosine
3'-monophosphate (dGp) was present. Following 32P-post- labeling, the
enzymatic and synthetic adduct were extracted from PEI- cellulose plates
and were shown to have the same HPLC elution profiles for the bisphosphate
adduct (32P-dpGp-ABZ). Treatment of the enzymatic and synthetic
bisphosphate adduct with nuclease P1 yielded a product that eluted at the
same time from the HPLC (32P-dpG-ABZ). Additional experiments demonstrated
that the PHS-derived 5'-monophosphate (dpG- ABZ) and 3'-monophosphate
(dGp-ABZ) adducts were also identical to their corresponding synthetic
standard. With comparable amounts of total ABZ metabolism, PHS produced
approximately 40-fold more dGp-ABZ than horseradish peroxidase (1943 +/-
339 versus 49 +/- 7.8 fmol/mg dGp). Adduct formation was dependent upon the
presence of peroxidase and the specific substrate, i.e. arachidonic acid or
H2O2. Adduct formation by PHS was inhibited by indomethacin (0.1 mM),
ascorbic acid (1 mM) and glutathione (10 mM), but not by
5,5-dimethyl-1-pyrroline N- oxide (DMPO) (100 mM), a radical scavenger.
Horseradish peroxidase adduct formation was also inhibited by ascorbic acid
and glutathione. In addition, DMPO elicited greater than a 96% inhibition.
Results demonstrate peroxidatic metabolism of ABZ to form dGp-ABZ. The
mechanism of dGp-ABZ formation by PHS and horseradish peroxidase may be
different.
相似文献