全文获取类型
收费全文 | 338篇 |
免费 | 22篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 25篇 |
妇产科学 | 4篇 |
基础医学 | 35篇 |
口腔科学 | 6篇 |
临床医学 | 32篇 |
内科学 | 90篇 |
皮肤病学 | 4篇 |
神经病学 | 13篇 |
特种医学 | 68篇 |
外科学 | 21篇 |
综合类 | 8篇 |
预防医学 | 18篇 |
药学 | 7篇 |
肿瘤学 | 41篇 |
出版年
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 8篇 |
2012年 | 3篇 |
2011年 | 7篇 |
2010年 | 13篇 |
2009年 | 19篇 |
2008年 | 14篇 |
2007年 | 18篇 |
2006年 | 5篇 |
2005年 | 10篇 |
2004年 | 6篇 |
2003年 | 11篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 10篇 |
1998年 | 16篇 |
1997年 | 12篇 |
1996年 | 12篇 |
1995年 | 11篇 |
1994年 | 18篇 |
1993年 | 14篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 11篇 |
1989年 | 12篇 |
1988年 | 11篇 |
1987年 | 11篇 |
1986年 | 10篇 |
1985年 | 12篇 |
1984年 | 5篇 |
1983年 | 8篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1978年 | 7篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1965年 | 2篇 |
排序方式: 共有373条查询结果,搜索用时 15 毫秒
1.
2.
Pleural malignant mesothelioma and non-occupational exposure to asbestos in Casale Monferrato, Italy. 总被引:6,自引:3,他引:3 下载免费PDF全文
C Magnani B Terracini C Ivaldi M Botta A Mancini A Andrion 《Occupational and environmental medicine》1995,52(6):362-367
OBJECTIVES--To assess and quantify the occurrence of pleural malignant mesotheliomas in people who neither experienced occupational exposure to asbestos nor were married to (or known to live with) workers exposed to asbestos in the workplace. The study was conducted in the area of the local health authority of Casale Monferrato, in north western Italy, where a large factory that produced asbestos cement was active up to 1985. No other major activities related to asbestos have ever been present in the area. METHODS--A retrospective survey covering the period 1980 to 1991 identified 126 incident pleural malignant mesotheliomas histologically diagnosed among residents in the local health authority (population at the 1981 census 98,000). Submission of 83 of 95 cases diagnosed during 1980-9 for revision by a panel of five expert pathologists led to the exclusion of 21. The 31 cases diagnosed in 1990-1 were not submitted for revision. For 64 of the 105 retained cases, information derived from different sources (rosters of the employees in the asbestos cement factory dated back to 1907, list of their spouses, clinical records) did not suggest occupational or paraoccupational exposure to asbestos. RESULTS--Incidence excludes cases for which there was some suggestion of occupational or paraoccupational exposure to asbestos. Incidence of histologically confirmed malignant mesothelioma among residents in the local health authority (annual x 100,000; age adjusted) was 4.2 in men and 2.3 in women (based on 26 and 18 cases respectively). In both sexes, rates in 1985-9 were higher than in the previous quinquennium. Corresponding estimates for 1990-1 (based on unrevised diagnoses) suggest similar rates in men and women. CONCLUSION--Rate ratios which are four to six times those measured by conventional Italian cancer registries can hardly be totally explained by bias produced by lack of recognition of occupational or paraoccupational exposure. The problem of proving this type of negative data is common to other circumstances of alleged cancer clusters of environmental (non occupational) origin. 相似文献
3.
Ciccone G Lorenzoni L Ivaldi C Ciccarelli E Piobbici M Arione R 《Epidemiologia e prevenzione》1999,23(3):188-196
Data available from the standard hospital discharge database (SDO) allow us to explore differences in health conditions according to different indicators of socioeconomic status (SES). We analysed all the patients aged 30-59, discharged from the S. Giovanni Battista (Molinette) hospital (the main general hospital in Turin, Italy) during three years (1996-1998) (n = 49949). Three health indicators were used as outcomes: a) emergency admission; b) severity of illness (according to the "All Patient Refined DRGs" subclasses); c) hospital mortality. Patients were compared for each outcome according to two different SES indicators: a) level of education; b) employment status. Logistic regression models (both conditional and unconditional) were used to adjust for several potential confounders. Patients with lower education (up to 5 years of schooling), compared to those with 13 or more years of schooling, showed a higher probability of being admitted through the emergency ward (29.1% vs 23.3%), with an odds ratio (OR) = 1.56-95% confidence interval (95% CI) = 1.45-1.68; of being classified in higher severity subclasses of illness (23.3% vs 17.7%, OR = 1.14; 95% CI = 1.07-1.22) and of dying in hospital (2.3% vs 1.6%). However, after adjustment for other prognostic factors (as severity of illness and specific expected mortality), this association disappeared (OR = 1.05, 95% CI = 0.84-1.32). Similar, but somewhat stronger, associations were observed when comparing the unemployed versus the employed. The corresponding figures (ORs; 95% CI) were 1.57 (1.42-1.74) for emergency admission; 1.31 (1.18-1.45) for severity of illness and 1.55 (1.10-2.16) for hospital mortality. In conclusion, this study showed that SES differentials in health are clearly measurable through routine hospital information systems, and documented that patients of low SES, particularly unemployed, experienced a delayed access to hospital, were admitted in poorer general health conditions and had a more unfavourable prognosis. 相似文献
4.
5.
Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
6.
Serum PDGF-AB in pleural mesothelioma. 总被引:2,自引:0,他引:2
Rosa Filiberti Paola Marroni Monica Neri Andrea Ardizzoni Pier Giacomo Betta Mara A Cafferata Pier Aldo Canessa Riccardo Puntoni Giovanni Paolo Ivaldi Michela Paganuzzi 《Tumour biology》2005,26(5):221-226
Overexpression of platelet-derived growth factor (PDGF) has been observed in lung and pleural tumors. The aim of this study was to evaluate the diagnostic and prognostic role of serum PDGF in pleural mesothelioma (PM). Four groups of subjects were studied: 93 malignant PM patients, 33 primary non small cell lung cancer patients, 51 subjects exposed to asbestos, defined as high-risk controls, and 24 healthy controls. PDGF-AB mean concentration was higher in PM patients (45.8 ng/ml) than in high-risk controls (33.1 ng/ml) and healthy controls (26.8 ng/ml). Using the cut-off level of 49.8 ng/ml, corresponding to the mean+2SD of PDGF-AB in healthy controls, 43% of PM patients showed positive PDGF-AB levels. Survival was evaluated in 82 PM patients. At the end of the follow-up (median 9.8 months) 80.5% of patients had died. Median survival was 13.1 and 7.9 months for patients with PDGF-AB lower and higher than the cut-off, respectively. Adjusting for age, sex, histology and platelet count, positive PDGF-AB levels were associated with lower survival (OR=1.2, 95%CI: 0.9-1.6), even if not significantly so. In conclusion, serum PDGF may represent a useful additional parameter to prognostic factors already available for PM. 相似文献
7.
Influence of oxygen tension on the viscoelastic behavior of red blood cells in sickle cell disease 总被引:2,自引:0,他引:2
Although the rheological behavior of sickle cell suspensions and of hemoglobin S solutions is known to be strongly dependent on oxygen tension (PO2), little data exist concerning the influence of PO2 on the viscoelasticity of individual HbSS RBC. We have used micropipette aspiration techniques to test the deformation response of both HbSS and control HbAA RBC over a wide range of PO2 at 23 degrees C. Sickled, spiculed HbSS cells were present for PO2 approximately less than 35 mm Hg; for a number of these cells, the deformation response was essentially elastic and an effective membrane rigidity (EMR) was calculated. EMR increased with decreasing PO2 and was approximately 5 to 50 times higher than the equivalent rigidity of oxygenated HbSS RBC. In addition, the rate of membrane deformation was very slow for sickled cells; the half-time for the deformation process increased as PO2 was lowered and was about two orders of magnitude longer than the equivalent time for normal RBC. Other sickled cells exhibited plastic deformation when subjected to comparable deforming forces and experienced irreversible membrane deformation and budding. At all PO2 levels tested, some HbSS RBC remained as discocytes; these cells had normal membrane elasticity and membrane viscosity. Furthermore, changes in PO2 did not affect the membrane properties of HbAA RBC. Thus, gross abnormalities in the deformation response of HbSS RBC were only detected after morphological sickling had occurred. These abnormalities most likely arose from changes in the cytoplasmic HbS viscoelasticity and, if present in vivo, would be expected to impair the flow of HbSS cells in the microcirculation. 相似文献
8.
High throughput functional microdissection of pathogen-specific T-cell immunity using antigen and lymphocyte arrays 总被引:2,自引:0,他引:2
The analysis of the human T-cell response specific for relevant pathogens is useful for diagnostic purposes and for research. Several methods enumerate antigen specific T-cells and measure their functions. Since screening of numerous antigens from pathogens is often needed to evaluate immunocompetence, lymphocytes, labor and cost are limiting factors. To examine pathogen-specific T-cell immunity, we have miniaturized the analysis of T-cell responses using an array approach in 384- and 1536-well plates with as few as 10 x 10(3) PBMC per well instead of the 500 x 10(3) PBMC used for current assays. Secreted cytokines were detected in the same wells used for lymphocyte cultures. The method can detect about ten CMV specific T-cells diluted into 50 x 10(3) PBMC (0.02%), and can quantify secreted cytokines. The microarray approach allowed evaluation of T-cell immunity in children with a sensitivity higher than current methods. When applied to CMV epitope mapping, the data obtained with conventional methods were confirmed. The assay could be automated, allowing high throughput processing. The assay provides quantitative information on cytokines induced by antigen stimulation and can be applied in a simplified format as a field test to monitor T-cell immunity in vaccine trials or in veterinary medicine. 相似文献
9.
T helper (Th) cells and cytolytic T lymphocytes (CTL) play defined roles in the cellular immune response. This distinction wavered when Th lymphocytes were shown to kill antigen-presenting cells displaying the relevant antigen. Here we demonstrate that also the opposite can be true: CTL can exert helper functions. We noticed that certain CMV-specific CTL lines grew after antigen activation also without exogenous IL-2. These lines produced their own IL-2, which supported the expansion of other CTL and Th cell lines. High levels of helper cytokines like IL-4, IL-5 and IL-6 were detected in the culture supernatants. Thus, we set up a helper assay to study the functional interactions between T cells (or their supernatants) and B cells. Conditioned media from helper CTL lines induced secretion of antigen-specific antibodies by B cells pulsed with antigen as first signal. We conclude that it is possible to isolate CTL lines that exhibit helper functions for T cells and B cells. If this possibility is proven also in vivo, we should revise some of our views on the pathogenesis of diseases in which CD8 cells are key players, such as in viral infections, graft rejection and GVHD. 相似文献
10.
Abstract: The study of plasma integrates physics, chemistry, biology, and engineering, and has recently engaged medicine and dental hygiene in research efforts. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous waste management, decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumours and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and enviornmental pathogens, heat-sensitive materials, contaminated medical waste, hard and soft surfaces, and ventilation systems may assist health care facilities in the management of various health concerns. The role that Low Temperature Atmospheric Pressure Plasma (LTAPP) could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, noncorrosive, more economical alternative, as well as support green healthcare. 相似文献