全文获取类型
收费全文 | 555篇 |
免费 | 25篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 4篇 |
妇产科学 | 16篇 |
基础医学 | 51篇 |
口腔科学 | 20篇 |
临床医学 | 33篇 |
内科学 | 172篇 |
皮肤病学 | 5篇 |
神经病学 | 49篇 |
特种医学 | 60篇 |
外科学 | 67篇 |
综合类 | 3篇 |
一般理论 | 1篇 |
预防医学 | 18篇 |
眼科学 | 7篇 |
药学 | 53篇 |
中国医学 | 2篇 |
肿瘤学 | 14篇 |
出版年
2023年 | 3篇 |
2021年 | 5篇 |
2020年 | 4篇 |
2019年 | 7篇 |
2018年 | 7篇 |
2017年 | 14篇 |
2016年 | 12篇 |
2015年 | 9篇 |
2014年 | 11篇 |
2013年 | 28篇 |
2012年 | 28篇 |
2011年 | 31篇 |
2010年 | 16篇 |
2009年 | 18篇 |
2008年 | 20篇 |
2007年 | 29篇 |
2006年 | 15篇 |
2005年 | 15篇 |
2004年 | 17篇 |
2003年 | 26篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 9篇 |
1999年 | 15篇 |
1998年 | 15篇 |
1997年 | 13篇 |
1996年 | 6篇 |
1995年 | 9篇 |
1994年 | 3篇 |
1993年 | 5篇 |
1992年 | 10篇 |
1991年 | 15篇 |
1990年 | 16篇 |
1989年 | 9篇 |
1988年 | 15篇 |
1987年 | 6篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1980年 | 5篇 |
1977年 | 8篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1974年 | 7篇 |
1973年 | 3篇 |
1972年 | 3篇 |
1954年 | 4篇 |
1949年 | 2篇 |
排序方式: 共有582条查询结果,搜索用时 15 毫秒
1.
SH Lee† CP Choi‡ HC Eun† OS Kwon† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):860-863
BACKGROUND: On December 26, 2004, the biggest earthquake for 40 years, measuring 9.0 on the Richter scale, triggered a tsunami that pounded the coastal areas of South Asia and East Africa. The effects of the tsunami on skin conditions have not been evaluated. OBJECTIVE: To determine the influence of the tsunami on skin conditions by evaluating the skin problems of patients presenting at hospitals after the tsunami. METHODS: Between 5 and 25 January 2005, two dermatologists evaluated patients who complained of skin problems at an outpatient clinic and emergency room of a general hospital in Banda Aceh, Aceh Province, Indonesia. RESULTS: The total number of patients that presented during the study period was 235 (131 males and 104 females), and they had a total of 265 skin problems. In terms of age distribution, most subjects were in their fourth decade (23.0%), followed by the third (22.6%) and fifth decade (16.6%). The most prevalent skin problems were infections-infestations (32.5%), followed by eczemas (29.8%) and traumatic skin disorders (29.4%). In males, traumatic skin disorders were most common. The great majority of infection-infestation cases involved superficial fungal infections. Contact dermatitis accounted for three-quarters of eczema cases, and mainly involved the arms (40.0%) and legs (27.1%). The majority of traumatic skin disorders were lacerations, punctures and penetrations, and the feet (44.7%) and hands (18.8%) were most frequently affected. CONCLUSIONS: Unhygienic conditions, exposure to a hazardous environment and contact with various objects during and after the tsunami probably increased the prevalence of infections-infestations, traumatic skin disorders and contact dermatitis. To prevent these problems and associated secondary bacterial infections, health-related education and early medical management are required. 相似文献
2.
A Marroni P B Bennett F J Cronje R Cali-Corleo P Germonpre M Pieri C Bonuccelli C Balestra 《Undersea & hyperbaric medicine》2004,31(2):233-243
In spite of many modifications to decompression algorithms, the incidence of decompression sickness (DCS) in scuba divers has changed very little. The success of stage, compared to linear ascents, is well described yet theoretical changes in decompression ratios have diminished the importance of fast tissue gas tensions as critical for bubble generation. The most serious signs and symptoms of DCS involve the spinal cord, with a tissue half time of only 12.5 minutes. It is proposed that present decompression schedules do not permit sufficient gas elimination from such fast tissues, resulting in bubble formation. Further, it is hypothesized that introduction of a deep stop will significantly reduce fast tissue bubble formation and neurological DCS risk. A total of 181 dives were made to 82 fsw (25 m) by 22 volunteers. Two dives of 25 min and 20 min were made, with a 3 hr 30 min surface interval and according to 8 different ascent protocols. Ascent rates of 10, 33 or 60 fsw/min (3, 10, 18 m/min) were combined with no stops or a shallow stop at 20 fsw (6 m) or a deep stop at 50 fsw (15 m) and a shallow at 20 fsw (6 m). The highest bubbles scores (8.78/9.97), using the Spencer Scale (SS) and Extended Spencer Scale (ESS) respectively, were with the slowest ascent rate. This also showed the highest 5 min and 10 min tissue loads of 48% and 75%. The lowest bubble scores (1.79/2.50) were with an ascent rate of 33 fsw (10 m/min) and stops for 5 min at 50 fsw (15 m) and 20 fsw (6 m). This also showed the lowest 5 and 10 min tissue loads at 25% and 52% respectively. Thus, introduction of a deep stop significantly reduced Doppler detected bubbles together with tissue gas tensions in the 5 and 10 min tissues, which has implications for reducing the incidence of neurological DCS in divers. 相似文献
3.
SUMMARY The study explored the incidence of clinical feminisation and the sex hormone levels of 18 Nigerian patients with liver cirrhosis (LC) alone and 18 patients with LC and hepatocellular carcinoma (HCC). The incidence (11%) of clinical feminisation in Nigerian patients was lower than values reported from other countries and there was no association between feminising signs and the sex hormone levels of the patients. Plasma oestradiol and sex hormone-binding globulin (SHBG) levels were significantly higher and testosterone lower in patients with liver diseases than in 18 age-matched normal controls. Serum concentrations of oestradiol were also found to be significantly higher in patients with LC alone than in those with LC and HCC. A possible promotive role for oestrogens in the development of HCC from the cirrhotic liver is discussed. 相似文献
4.
L. Ressia M.D. A.M. Grande M.D. R. Gaeta M.D. G. De Pieri M.D. M. Aiello M.D. M. Viganò M.D. 《Journal of cardiac surgery》1997,12(6):431-433
A bstract Eight patients (4 men, 4 women), mean age 51 years, referred to our Institution for left atrial myxoma underwent removal of the tumor through a superior transseptal approach. All patients in sinus rhythm with normal conduction time. The myxomas were localized in the fossa ovalis (3 cases), interatrial septum (2 cases), left appendage (2 cases), and mitral annulus (1 case). One patient died in hospital after emergency operation for low-output syndrome complicated by septic shock. All other patients had an uneventful postoperative course. Atrial arrhythmias did not represent a major postoperative complication. Transient PR interval elongation was occasionally seen. Electrophysiological studies showed normal sinus node function. At 6 months following operation, patients were evaluated with transeso-phageal echocardiography. There was no tumor recurrence. There were no episodes of arrhythmia in 24-hour electrocardiographic monitoring, and all patients were in NYHA Class I. We believe that the superior transseptal approach gives optimal exposure of the left atrial cavity, overcoming all difficulties related to a small left atrium which is an usual pattern in left atrial myxomas. 相似文献
5.
6.
Inhibition of 2-nitropropane-induced rat liver DNA and RNA damage by benzyl selenocyanate 总被引:5,自引:2,他引:3
We observed that pretreatment of male F344 rats with benzyl selenocyanate,
a versatile organoselenium chemopreventive agent in several animal model
systems, decreases the levels of DNA and RNA modifications produced in the
liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms
involved, we pretreated male F344 rats with either benzyl selenocyanate,
its sulfur analog benzyl thiocyanate, phenobarbital or cobalt
protoporphyrin IX; the latter is a depletor of P450. We then determined (1)
the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on
2-nitropropane- induced liver DNA and RNA modifications and (3) amount of
nitrate excreted in rat urine following administration of the carcinogen.
Pretreatment with benzyl selenocyanate or phenobarbital increased the
denitrification activity of liver microsomes by 217 and 765%, respectively,
increased liver P4502B1 by 31- and 435-fold, respectively, decreased the
levels of 2-nitropropane-induced modifications in liver DNA (29-70% and
17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and
increased the 24-h urinary excretion of nitrate by 157 and 209%,
respectively. Pretreatment with benzyl thiocyanate had no significant
effect on any of these parameters. Pretreatment with cobalt protoporphyrin
IX decreased liver P4502B 1 by 87%, decreased the denitrification activity
of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate
by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic
acid modifications by 17-67%. These results indicate that the metabolic
sequence from 2-nitropropane to the reactive species causing DNA and RNA
modifications does not involve the removal of the nitro group. Moreover,
they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic
acid modifications in part by increasing its detoxication through induction
of denitrification, although it is evident that other mechanisms must also
be involved.
相似文献
7.
8.
Pieri C Moroni F Recchioni R Marcheselli F Falasca M Antonicelli R Damjanovich S 《Archives of gerontology and geriatrics》1992,14(2):145-154
Depolarizing effects of increasing concentrations of extracellular K(+), as well as the repolarizing effect of bretylium tosylate (BT) were evaluated in human lymphocytes from young and elderly volunteers. Cells from elderly volunteers were less responsive to depolarization induced by increased extracellular potassium concentrations than those from young volunteers. Upon a near complete depolarization induced by 140 mM K(+) in the extracellular space, a significant amount of non-responding cells were found in samples from elderly volunteers. BT, which opens the otherwise silent Na(+) channels of partially depolarized cells, with subsequent activation of the Na(+)-K(+) pump (Pieri et al., 1989). repolarized both young and old lymphocytes. However, the degree of the repolarization was only 40% in the case of lymphocytes from elderly volunteers than from that of the young. It is suggested that an increase of membrane microviscosity, characteristic of old cells, may be at least partially responsible for the decreased responsiveness of plasma membrane functions which were observed. 相似文献
9.
Gianfranco Liguri Cristina Cecchi Stefania Latorraca Alessandro Pieri Sandro Sorbi Donatella Degl'Innocenti Giampietro Ramponi 《Neuroscience letters》1996,210(3):153-156
Acylphosphatase (ATPase), an enzyme that modulates the activity of Ca2+-ATPase by hydrolysing its phosphorylated moiety, has been found to be significantly higher in cultured skin fibroblasts from donors affected by early onset familial Alzheimer's disease (EOFAD) with PS-1 and PS-2 gene mutations. Of the two known isoenzymes of acylphosphatase, only the erythrocyte one accounts for the total increase in activity. No relevant alteration was observed in phosphotyrosine phosphatase activity (PTPase), in Ca2+-ATPase and Na+,K+-ATPase activities of the same cells as compared to age-matched controls. This finding could suggest a possible explanation for the calcium-dependent biochemical alterations previously described in Alzheimer's disease fibroblasts. 相似文献
10.
S. Ascani P. L. Zinzani F. Gherlinzoni E. Sabattini A. Briskomatis A. de Vivo M. Piccioli G. Fraternali Orcioni F. Pieri A. Goldoni P. P. Piccaluga D. Zallocco R. Burnelli L. Leoncini B. Falini S. Tura S. A. Pileri 《Annals of oncology》1997,8(6):583-592
Background: One hundred sixty-eight peripheral T-cell lymphomas (PTCLs)were reviewed according to the Revised European–American Lymphoma (R.E.A.L.)Classification.Patients and methods: The cases, originally diagnosed on the basis of theUpdated Kiel Classification (UKC), were all provided with histologicalpreparations, immunophenotype, clinical information, and follow-up data. Theslides were reclassified by five observers, who integrated the R.E.A.Lcriteria with cell size measurements. The prognostic value of clinical andpathologic findings was assessed by univariate and multivariate analysis.Results: The R.E.A.L. Classification was reproducibly applied by all of theobservers. Clinically, anaplastic large cell lymphomas (ALCLs) differed fromthe remaining PTCLs by mean age (29.5 vs. 52.9 years), bulky disease(52.3% vs. 11.3%; P = 0.000), mediastinal mass (52.7% vs.32%; P = 0.004), and disease-free survival (68.0% vs.38.2%; P = 0.0001). Although each histological type displayed specificclinical aspects, PTCLs other than ALCL were basically characterised by a poorclinical outcome which was not influenced by the UKC malignancy grade. Atmultivariate analysis, the risk of a lower complete remission rate was relatedto bulky disease (P = 0.001), histologic group (non-ALCL) (P = 0.01), andadvanced stage (III–IV) (P = 0.0002).Conclusions: The present study supports the classification of T-celllymphomas proposed by the R.E.A.L. scheme. 相似文献