全文获取类型
收费全文 | 1189篇 |
免费 | 45篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 17篇 |
妇产科学 | 12篇 |
基础医学 | 105篇 |
口腔科学 | 8篇 |
临床医学 | 76篇 |
内科学 | 319篇 |
皮肤病学 | 11篇 |
神经病学 | 32篇 |
特种医学 | 177篇 |
外科学 | 288篇 |
综合类 | 7篇 |
预防医学 | 32篇 |
眼科学 | 21篇 |
药学 | 45篇 |
中国医学 | 1篇 |
肿瘤学 | 93篇 |
出版年
2022年 | 12篇 |
2021年 | 24篇 |
2020年 | 10篇 |
2019年 | 26篇 |
2018年 | 23篇 |
2017年 | 21篇 |
2016年 | 26篇 |
2015年 | 23篇 |
2014年 | 35篇 |
2013年 | 49篇 |
2012年 | 63篇 |
2011年 | 58篇 |
2010年 | 28篇 |
2009年 | 32篇 |
2008年 | 43篇 |
2007年 | 51篇 |
2006年 | 38篇 |
2005年 | 37篇 |
2004年 | 43篇 |
2003年 | 31篇 |
2002年 | 32篇 |
2001年 | 32篇 |
2000年 | 24篇 |
1999年 | 30篇 |
1998年 | 20篇 |
1997年 | 31篇 |
1996年 | 29篇 |
1995年 | 25篇 |
1994年 | 27篇 |
1993年 | 15篇 |
1992年 | 12篇 |
1991年 | 22篇 |
1990年 | 16篇 |
1989年 | 31篇 |
1988年 | 22篇 |
1987年 | 15篇 |
1986年 | 24篇 |
1985年 | 17篇 |
1984年 | 21篇 |
1983年 | 7篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 17篇 |
1978年 | 8篇 |
1977年 | 13篇 |
1976年 | 6篇 |
1975年 | 12篇 |
1973年 | 4篇 |
1968年 | 4篇 |
排序方式: 共有1247条查询结果,搜索用时 62 毫秒
71.
A case is reported of spontaneous ectopic pregnancy in a non patent fallopian tube of a patient with a contralateral unicornuate uterus without rudimentary horn. A hemoperitoneum, due to the rupture of the tube, occurred with a HCG level of 48 I.U./l. A laparoscopy was therefore performed and the fallopian tube removed. 相似文献
72.
The authors intend to draw the attention on the issue of tetanus infections in adult patients whose history is often unknown or incomplete. For these people, current regulations (Presidential Decree 7th Nov 2001 no. 464) provides for more extended vaccination coverage. The input data were drawn by different sources (ISS; MS; National Statistics Institute; Campania Epidemiological Observatory) and allowed for the tetanus infections having occurred in Italy and Campania in the last ten years. 相似文献
73.
OBJECTIVE: After completion of an earlier endoscopic transsphenoidal anatomic study, we studied various endoscopic transsphenoidal approaches using cadaveric specimens to develop endoscopic endonasal surgical approaches to the cavernous sinus. METHODS: Ten cavernous sinuses in five artery-injected adult cadaveric heads were studied with 0-, 30-, and 70-degree angled 4-mm rod-lens endoscopes. The extent of the surgical exposure, the skewed endoscopic anatomic view, and the maneuverability of surgical instruments through their relative operating spaces were studied after various endoscopic endonasal approaches via one nostril. RESULTS: The paraseptal approach was used between the nasal septum and the middle turbinate and provided exposure at the anteromedial portion of the cavernous sinus. The contralateral paraseptal approach rendered a slightly more medial view at the cavernous sinus than did the ipsilateral approach. This approach offered limited surgical access to the lateral vertical compartment. The middle turbinectomy approach allowed surgical access to the lateral wall of the cavernous sinus, except for the superior orbital fissure and the orbital apex. The middle meatal approach, which was made between the middle turbinate and the lateral nasal wall, revealed the entire lateral vertical compartment of the cavernous sinus, including the orbital apex and the superior orbital fissure. However, its lateral tangential surgical trajectory and the absence of dedicated surgical tools limited the surgeon's surgical maneuverability. A combination of the middle turbinectomy and middle meatal approaches increased the operating space. CONCLUSION: Various endoscopic endonasal surgical approaches to the cavernous sinus were studied using adult cadaveric head specimens. 相似文献
74.
S. Crovella RR. Moura S. Cappellani F. Celsi E. Trevisan M. Schneider 《Journal of toxicology and environmental health. Part A》2018,81(5):98-105
The presence of asbestos bodies (ABs) in lung parenchyma is considered a histopathologic hallmark of past exposure to asbestos fibers, of which there was a population of longer fibers. The mechanisms underlying AB formation are complex, involving inflammatory responses and iron (Fe) metabolism. Thus, the responsiveness to AB formation is variable, with some individuals appearing to be poor AB formers. The aim of this study was to disclose the possible role of genetic variants of genes encoding inflammasome and iron metabolism proteins in the ability to form ABs in a population of 81 individuals from North East Italy, who died after having developed malignant pleural mesothelioma (MPM). This study included 86 genetic variants distributed in 10 genes involved in Fe metabolism and 7 genetic variants in two genes encoding for inflammasome molecules. Genotypes/haplotypes were compared according to the number of lung ABs. Data showed that the NLRP1 rs12150220 missense variant (H155L) was significantly correlated with numbers of ABs in MPM patients. Specifically, a low number of ABs was detected in individuals carrying the NLRP1 rs12150220 A/T genotype. Our findings suggest that the NLRP1 inflammasome might contribute in the development of lung ABs. It is postulated that the NLRP1 missense variant may be considered as one of the possible host genetic factors contributing to individual variability in coating efficiency, which needs to be taken when assessing occupational exposure to asbestos. 相似文献
75.
Daniela Vitucci Angela Amoresano Marcella Nunziato Simona Muoio Andreina Alfieri Giovannangelo Oriani Luca Scalfi Luigi Frusciante Maria Manuela Rigano Piero Pucci Luigi Fontana Pasqualina Buono Francesco Salvatore 《Nutrients》2021,13(4)
The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée. 相似文献
76.
Claudia Fumarola Mara A. Bonelli Pier Giorgio Petronini Roberta R. Alfieri 《Biochemical pharmacology》2014
While PI3K/AKT/mTOR pathway is altered in a variety of cancers including non small cell lung cancer, abnormalities in this pathway are more common in squamous cell lung carcinoma than in adenocarcinoma of the lung. Moreover, aberrant activation of PI3K/AKT/mTOR pathway is one of the mechanisms of acquired resistance to EGFR-TK inhibitors in patients with adenocarcinoma carrying EGFR activating mutations. 相似文献
77.
Flair J Carrilho Cleusa R Moraes João RR Pinho Isabel MVGC Mello Dennis A Bertolini Marcílio F Lemos Regina C Moreira Leda C Bassit Rita A Cardoso Gabriela Ribeiro-dos-Santos Luiz C Da Silva 《BMC public health》2004,4(1):1-11
Background
Patients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil.Methods
This study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units.Results
Frequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection.Conclusions
Frequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters ≥ 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission. 相似文献78.
KM RAI KJ PHILIPOSE VSM P TAKKAR RR BHONDE KK MAUDAR NK PANICKER 《Medical Journal Armed Forces India》1999,55(2):119-122
Current synthetic vascular prostheses do not acquire lining of vascular endothelium in humans or dogs. Endothelial seeding of vascular grafts has been proposed as a means of reducing the thrombogenicity of these grafts. We examined feasibility of cultivating endothelial cells (EC) by tissue culture technique and their subsequent seeding onto small diameter polytetra fluoroethylene (PTFE) grafts. Twenty adult dogs underwent common carotid artery interposition with 4 mm PTFE grafts. Ten dogs received seeded and the remaining ten received unseeded grafts. Grafts were removed at 4 and 12 weeks and their gross/morphological features compared. Cumulative patency rates for seeded grafts were 70% as compared to unseeded ones 30%. Seeded grafts were completely surfaced with a mono-layer of endothelium by 4 weeks. Small graft patency appears to be related to the establishment of an endothelial surface, the development of which is clearly facilitated by seeding with autogenous endothelium.KEY WORDS: Endothelial cell seeding, Vascular grafts 相似文献
79.
F Pacelli G B Doglietto S Alfieri C Carriero M Malerba P F Crucitti P Caprino F Crucitti 《Hepato-gastroenterology》1999,46(26):1223-1228
BACKGROUND/AIMS: Few reports from the Western hemisphere have investigated the impact of pathological features and surgical modalities on the prognosis of patients affected by early gastric cancer (EGC). In particular, the extent of lymphadenectomy (limited vs. extended) and the type of gastric resection (subtotal vs. total) remain controversial issues in the management of EGC. The aim of this study was to identify factors influencing prognosis in patients affected by EGC. METHODOLOGY: Hospital records and pathological specimens of 72 patients with EGC undergoing resective surgery during the period 1981-1995 were retrospectively reviewed. Patient status was determined by follow-up examination or by telephone contact. Univariate and multivariate analysis was used to calculate the 5-year survival probabilities with respect to the following variables: age (< or = 65, > 65), sex, depth of invasion (mucosal, submucosal) tumor location (upper, middle and lower third), gross appearance (type I, type II and type III), size (< or = 1.5 cm, > 1.5 cm), presence or absence of lymph node metastasis, histological type (intestinal, diffuse), extent of lymphadenectomy (limited or extended), and type of gastrectomy (total or distal subtotal). Survival was the outcome variable studied. RESULTS: Multivariate logistic regression analysis showed that age, nodal involvement and depth of invasion were independently associated with poor survival. CONCLUSIONS: Results showed a significant dominance of host- and tumor-related factors over the type of surgical procedure on prognosis of EGC patients. 相似文献
80.
Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns. 相似文献