全文获取类型
收费全文 | 1294篇 |
免费 | 189篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 57篇 |
妇产科学 | 20篇 |
基础医学 | 92篇 |
口腔科学 | 38篇 |
临床医学 | 211篇 |
内科学 | 276篇 |
皮肤病学 | 108篇 |
神经病学 | 58篇 |
特种医学 | 133篇 |
外科学 | 187篇 |
综合类 | 94篇 |
现状与发展 | 30篇 |
预防医学 | 53篇 |
眼科学 | 15篇 |
药学 | 38篇 |
中国医学 | 3篇 |
肿瘤学 | 70篇 |
出版年
2024年 | 19篇 |
2023年 | 179篇 |
2022年 | 13篇 |
2021年 | 18篇 |
2020年 | 55篇 |
2019年 | 21篇 |
2018年 | 52篇 |
2017年 | 45篇 |
2016年 | 39篇 |
2015年 | 56篇 |
2014年 | 83篇 |
2013年 | 62篇 |
2012年 | 33篇 |
2011年 | 37篇 |
2010年 | 74篇 |
2009年 | 92篇 |
2008年 | 28篇 |
2007年 | 51篇 |
2006年 | 20篇 |
2005年 | 19篇 |
2004年 | 13篇 |
2003年 | 16篇 |
2002年 | 15篇 |
2001年 | 12篇 |
2000年 | 14篇 |
1999年 | 28篇 |
1998年 | 35篇 |
1997年 | 51篇 |
1996年 | 40篇 |
1995年 | 35篇 |
1994年 | 29篇 |
1993年 | 34篇 |
1992年 | 10篇 |
1991年 | 10篇 |
1990年 | 13篇 |
1989年 | 22篇 |
1988年 | 21篇 |
1987年 | 14篇 |
1986年 | 5篇 |
1985年 | 11篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 9篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1978年 | 5篇 |
1977年 | 3篇 |
1976年 | 13篇 |
1975年 | 10篇 |
1974年 | 3篇 |
排序方式: 共有1503条查询结果,搜索用时 15 毫秒
991.
S Yaemsiri N Hou MM Slining K He 《Journal of the European Academy of Dermatology and Venereology》2010,24(4):420-423
Background Human nail clippings are increasingly used in epidemiological studies as biomarkers for assessing diet and environmental exposure to trace elements or other chemical compounds. However, little is known about the growth rate of human nails. Objective To estimate the average growth rate of fingernails and toenails and examine factors that may influence nail growth rate. Methods Twenty‐two healthy American young adults marked their nails close to the proximal nail fold with a provided nail file following a standardized protocol, and recorded the date and the distance from the proximal nail fold to the mark. One to three months later, participants recorded the date and distance from the proximal nail fold to the mark again. Nail growth rate was calculated based on recorded distance and time between the two measurements. Results Average fingernail growth rate was faster than that of toenails (3.47 vs. 1.62 mm/month, P < 0.01). There was no significant difference between right and left fingernail/toenail growth rates. The little fingernail grew slower than other fingernails (P < 0.01); the great toenail grew faster than other toenails (P < 0.01). Younger age, male gender, and onychophagia were associated with faster nail growth rate; however, the differences were not statistically significant. Conclusion Nail growth rates have increased compared with previous estimates conducted decades ago. Toenail clippings may reflect a long exposure time frame given the relatively slow growth rate. 相似文献
992.
O Abbas N Marrouch MM Kattar S Zeynoun AG Kibbi RA Rached GF Araj S Ghosn 《Journal of the European Academy of Dermatology and Venereology》2011,25(1):33-42
Background Only a few studies characterized cutaneous non‐tuberculous Mycobacterium (NTM) infections in this region of the world . Objective The aim of this study was to describe the epidemiological, clinical and histological findings of cutaneous NTM infections in Lebanon. Patients/Methods Retrospective study of 17 patients (19 histological specimens) diagnosed with cutaneous NTM infections and confirmed by culture‐based partial sequencing of the 16S rRNA gene at the American University of Beirut Medical Center between 2005 and 2008. Results Of 17 cases, 14 were caused by Mycobacterium marinum. All patients were immunocompetent except for one. Clinically, the most common presentation was multiple sporotrichoid lesions over an extremity (8/17). Many patients had peculiar presentations including bruise‐like patches, herpetiform lesions, annular ulcerated plaques, symmetrical nodules over the buttocks and locally disseminated lesions with surrounding pale halo. Almost all patients cleared their infection on either minocycline or clarithromycin monotherapies. Histologically, a dermal small vessel proliferation with mixed inflammation (granulation tissue‐like changes) was identified in 58% of specimens. The most common type of granulomatous inflammation was the suppurative (47%) followed by the tuberculoid (30%), sarcoidal (11%), and palisading (5%) types. Lichenoid granulomatous dermatitis was noted in 42% of cases. Special staining highlighted mycobacteria in only two specimens. Conclusions The incidence of cutaneous NTM infections is high in our area. Many patients had peculiar clinical presentations. Our study is the second to report the common presence of granulation tissue‐like changes as a good histological indicator of cutaneous NTM infections. Minocycline and clarithromycin remain the drugs of choice in our area. 相似文献
993.
MM Arias GM Alcaráz C. Bernal G. González 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(10):1047-1051
A clinical trial was conducted in order to prove the efficacy of a solution containing 50 g/1 of plantain flour and 3. 5 g/1 of sodium chloride (NaCl) for the rehydration of children with acute diarrheal diseases. 121 children were given WHO-ORS (Group A) and 117 a plantain flour-based solution (Group B). Rehydration was successful in 85. 9% in Group A and 88. 0% in Group B ( p = 0. 634). Rehydration was completed in 5. 28 h (SD 1. 99) in Group A and in 4. 88 h (SD 2. 11) in Group B ( p = 0. 132). The average solution intake for rehydration was 24. 56ml/kg/h (SD 10. 12) in Group A and 21. 17ml/kg/h (SD 9. 35) in Group B ( p = 0. 00782). The mean stool output during rehydration was 8. 45g/kg/h (SD 9. 72) in Group A and 4. 69 g/kg/h (SD 4. 98) in Group B ( p = 0. 00053). Decrease in blood levels of sodium and potassium occurred in some children in group B. The plantain flour-based solution proved effective for the treatment of dehydration due to acute diarrheal diseases and should be considered as an alternative when standard WHO-ORS is not available. 相似文献
994.
995.
Development of virtual CT cholangiopancreatoscopy 总被引:15,自引:0,他引:15
Prassopoulos P; Raptopoulos V; Chuttani R; McKee JD; McNicholas MM; Sheiman RG 《Radiology》1998,209(2):570
996.
Background: A significant number of soldiers suffer serious injuries or die in the process of demining and a protective device is necessary in such operations. 相似文献
997.
998.
Preimplantation genetic diagnosis of chromosome balance in embryos from a patient with a balanced reciprocal translocation 总被引:4,自引:1,他引:3
Duplications or deletions are present in a high percentage of the gametes
produced by individuals carrying balanced translocations. Preimplantation
genetic diagnosis was used to examine chromosome balance in embryos from a
patient having a reciprocal translocation within the short arms of
chromosomes 5 and 8 (46,XX,t(5;8)(p13;p23)). This woman has two sisters
with the translocation unbalanced, resulting in a partial trisomy for
chromosome 5 and partial monosomy for chromosome 8 (46,XX,-8,
+der(8)t(5;8)(p13;p23)) with associated mental retardation and physical
abnormalities. The patient and her husband desired to have children without
the abnormal chromosome balance and wished to reduce the likelihood of
spontaneous abortion or need for therapeutic abortion. Fluorescence in-situ
hybridization (FISH) probes for the alpha-satellite region of chromosome 8
and for a region on the short arm of chromosome 5 (5p15.2) were tested
initially on lymphocytes from the patient and her sisters. The
hybridization signal for chromosome 5 was detected in the expected two
copies for the patient and three copies for the sisters in 87% of the
cells. Two hybridization signals for chromosome 8 were detected in 96% of
the cells from all individuals. Additional probe testing was done using
blastomeres from polyspermic embryos. The couple then proceeded with a
stimulated in- vitro fertilization (IVF) cycle and biopsies were done on 13
embryos at the 7-10-cell stage using a method of zona drilling and fluid
displacement. Diagnosis was possible on at least one blastomere for nine
embryos. Three embryos had nuclei with three hybridization signals for
chromosome 5, three had fewer than two signals for one or both chromosomes,
one was mosaic, and two had two signals for each chromosome. The latter
were transferred to the patient, but pregnancy was not achieved. The
results demonstrate that preimplantation genetic diagnosis for patients
with reciprocal translocations can be used to identify embryos having
normal chromosome balance. The potential advantages and limitations of this
approach are discussed.
相似文献
999.
1000.
Background: Regional Trauma Centre in the northern India receives the mortal remains of all fallen soldiers for embalming. Non enemy action deaths during counter insurgency operations (CI Ops) were analysed for planning preventive measures. 相似文献