全文获取类型
收费全文 | 1710篇 |
免费 | 131篇 |
国内免费 | 5篇 |
学科分类
医药卫生 | 1846篇 |
出版年
2023年 | 24篇 |
2022年 | 34篇 |
2021年 | 104篇 |
2020年 | 64篇 |
2019年 | 89篇 |
2018年 | 88篇 |
2017年 | 61篇 |
2016年 | 65篇 |
2015年 | 70篇 |
2014年 | 62篇 |
2013年 | 97篇 |
2012年 | 105篇 |
2011年 | 111篇 |
2010年 | 71篇 |
2009年 | 53篇 |
2008年 | 91篇 |
2007年 | 96篇 |
2006年 | 87篇 |
2005年 | 74篇 |
2004年 | 65篇 |
2003年 | 45篇 |
2002年 | 54篇 |
2001年 | 19篇 |
2000年 | 10篇 |
1999年 | 18篇 |
1998年 | 10篇 |
1997年 | 8篇 |
1996年 | 10篇 |
1994年 | 4篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 7篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 10篇 |
1980年 | 8篇 |
1979年 | 5篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1974年 | 14篇 |
1973年 | 4篇 |
1971年 | 5篇 |
排序方式: 共有1846条查询结果,搜索用时 0 毫秒
1.
Tarek A. Amer Tarek F. Elwakil Mahmoud S. Elbasiouny 《European journal of plastic surgery》2007,30(2):67-73
Haemangiomas are the most common tumours of infancy. They typically proliferate then involute with considerable variation
as regards to their rates of proliferation and involution. Haemangioma of the nasal tip is a lesion of special characteristics.
During proliferation, it expands, contracts and deviates the nasal cartilages. Particularly, it regresses slowly and frequently
involutes incompletely. That is why excision of the lesion is frequently suggested. The present study was conducted to evaluate
open rhinoplasty after initial non-excision treatment modalities namely, intra-lesional corticosteroid injections and laser
treatment, as a protocol of treatment for nasal tip haemangiomas. Twelve patients with nasal tip haemangiomas were included
in the present study. Patients of both sexes, of different ages, with deep and mixed haemangiomas were studied. Disfigurement
was the constant presenting symptom. Initial non-excision treatment reported different responses as denoted by the regression
of the lesions’ size. Haemangiomas constantly extended between the medial crura of the alar cartilages as noted by the constant
widening of the columella pre-operatively and the obvious separation of the nasal cartilages intra-operatively. This separation
was constantly found to require approximation by sutures. The results of the present study concluded that whenever an early
presentation with nasal tip haemangioma could be established, initial non-excision treatment followed by open rhinoplasty
could be a useful protocol of treatment. Within the limitations of the present study, this protocol could achieve an early,
safe and effective treatment for nasal tip haemangiomas with provisionally acceptable cosmetic outcomes so far. 相似文献
2.
A total of 150 women in 3 equal groups, each using a different contraceptive method (group I used Norplant, group II used the IUD and group III used combined OC pills) were investigated for the presence of vaginal candidiasis before and at various time intervals (3, 6 and 12 months) after starting to use the particular contraceptive method. The incidence of vaginalCandida albicans infection increased significantly among pill and IUD users, but with a much lower intensity among the latter cases. In Norplant users the increase was slight and insignificant. The explanation of these findings within the context of changes in local vaginal milieu is discussed.
Sumario Un total de 150 mujeres en tres grupos iguales, cada uno usando un método anticonceptivo diferente (el grupo I usó Norplant, el grupo II usó DIU y el grupo III usó anticonceptivos orales combinados) fueron investigadas para la presencia de candidiasis vaginal, antes y luego de varios intervalos (3, 6 y 12 meses) después del comienzo del usó del método anticonceptivo aconsejado. La incidencia de infección vaginal por Candida albicans aumentó significativamente entre las usuarias de pastillas y de DIU pero, con mucho menos intensidad en las segundas. En usuarias de Norplant el aumento fue leve e insignificante. Se explican estos hallazgos en el contexto de cambios en el medio vaginal.
Resumé 150 femmes, réparties en 3 groupes égaux utilisant chacun une méthode contraceptive différente (le groupe I utilisait Norplant®, le groupe II un DIU et le groupe III un contraceptif oral combiné), ont été observées afin de détecter la présence d'une candidose vaginale avant et à intervalles réguliers (3, 6 et 12 mois) après le début de l'emploi de l'une de ces méthodes contraceptives. L'infection vaginale à candida albicans a une incidence plus élevée mais une intensité moindre chez les utilisatrices de pilule et de DIU. Parmi les utilisatrices de Norplant, I'augmentation était légère et néglibeable. La discussion porte sur l'explication de ces résultats dans le contexte des modifications du milieu vaginal local.相似文献
3.
4.
5.
6.
Amer MB 《Journal of medical engineering & technology》1999,23(6):240-245
This paper presents the design and implementation of a computer-based system for identification of the static characteristics of medical sensors. The static characteristic obtained is then used to correct the input-output non-idealities caused by nonlinearity effects, gain error, hysteresis and environmental effects. The knowledge of this characteristic enables digital signal processing of the sensor response, facilitates correction of input-output non-idealities and forms a compensation formula which is required for the optimal design of the experiment for medical sensor calibration. The identification system consists of a personal computer and a microcontroller-based electronic system. In consideration of practical situations special emphasis is oriented toward its user friendliness and future extendability. 相似文献
7.
Honn KV Aref A Chen YQ Cher ML Crissman JD Forman JD Gao X Grignon D Hussain M Porter AT Pontes JE Powell I Redman B Sakr W Severson R Tang DG Wood DP 《Pathology oncology research : POR》1996,2(1-2):98-109
Rates of prostate cancer (PCa) have increased so dramatically over the last decade that the age adjusted incidence rate for PCa is now greater than that any other cancer among men in the United States. This review, published as a three part series, provides a state-of-art assessment of the PCa problem in its divergent aspects.Part 1 covers epidemiology, incidence and progression. Several epidemiological studies have demostrated that first degree male relatives of men with PCa are at increased risk of developing the disease. Familial and genetic factors as well as medical, anthropometric, dietary, hormonal and occupational factors involved in PCa are discussed. Postmortem examination of the prostate in men without evidence of PCa documented a high frequency of adenocarcinoma. Latent disease occurred as early as the second decade of life. Although there is no significant difference in incidence between Caucasian and African-American males, high grade prostatic intraepithelial neoplasia (HGPIN) is higher in the latter group. While dietary fat, androgens and certain environmental factors may be determinants for PCa, the exact mechanism of tumorigenesis is still relatively unknown. The current thinking of the role of genomic instability, chromosomal alterations, tumor suppressor genes and the androgen receptor are explored. 相似文献
8.
Amer AF Zaki SA Nagati AM Darwish MA 《The Journal of the Egyptian Public Health Association》1996,71(3-4):273-284
Hepatitis E virus has been implicated as a frequent cause of acute sporadic hepatitis among Egyptian children. Moreover, an extraordinarily high seroprevalence rate was previously reported in a semiurban Nile Delta population. A conspicuous feature of hepatitis E is the high morbidity and mortality it can cause among infected pregnant women. We therefore evaluated the prevalence of HEV antibodies in adolescent females using a solid-phase enzyme linked immunoassay based on two recombinant hepatitis E virus antigens. A high prevalence rate (38.9%) was found in 95 apparently healthy adolescent females. The mean age of the study subjects was 21.81 +/- 2.5 (SD) range 16-25 years. Eighty (84.2%) subjects resided in Alexandria, while 15 (15.8%) came from semiurban villages of Alexandria Governorate. An increased prevalence was noted with age, as anti-HEV antibodies were detected in 32.1% and 41.8% of study participants in the second and third decades of life, respectively. Similarly, those illiterate or having received less than primary education exhibited a higher HEV prevalence than those with higher education (46.3% vs 29.3%). The majority of subjects having serological evidence of HEV infection denied previous history of jaundice which shows that HEV infection was subclinical in those cases. Ten (55.6%) pregnant females participating in the study, as well as 48 (62.3%) non pregnant females lacked serological evidence of HEV infection; i.e., 60.01% (10 + 48 out of 95) of women in the childbearing age may be susceptible to infection. This report suggests that HEV is endemic in Alexandria, Egypt; the epidemiologic risk factors associated with HEV infection need further exploration. 相似文献
9.
10.
Physical activity combined with massage improves bone mineralization in premature infants: a randomized trial. 总被引:5,自引:0,他引:5
Hany Aly Mohamed F Moustafa Sahar M Hassanein An N Massaro Hanna A Amer Kantilal Patel 《Journal of perinatology》2004,24(5):305-309
BACKGROUND: Osteopenia of prematurity is a known source for morbidity in preterm infants. Premature infants have shown favorable outcomes in response to massage and physical activity. Whether such intervention can stimulate bone formation or decrease bone resorption is yet to be determined. OBJECTIVE: To test the hypothesis that massage combined with physical activity can stimulate bone formation and ameliorate bone resorption in premature infants. DESIGN/METHODS: A prospective double-blinded randomized trial was conducted at the Neonatal Intensive Care Unit of Ain Shams University in Cairo, Egypt. Thirty preterm infants (28 to 35 weeks' gestation) were randomly assigned to either control group (Group I, n=15) or intervention group (Group II, n=15). Infants in the intervention group received a daily protocol of combined massage and physical activity. Serum type I collagen C-terminal propeptide (PICP) and urinary pyridinoline crosslinks of collagen (Pyd) were used as indices for bone formation and resorption, respectively. PICP and Pyd were measured at enrollment and at discharge for all subjects. t-Test, ANOVA and linear regression analysis were used for statistical analyses. RESULTS: There was no difference between groups I and II in gestational age (32.1+/-1.8 vs 31.5+/-1.4 weeks) or birth weight (1.429+/-0.148 vs 1.467+/-0.132 g). In the control group, serum PICP decreased over time from 82.3+/-8.5 to 68.78+/-14.6 (p<0.01), while urinary Pyd increased from 447.7+/-282.8 to 744.9+/-373.6 (p<0.01) indicating decreased bone formation and increased bone resorption, respectively. In the intervention group, serum PICP increased over time from 62.5+/-13.8 to 73.84+/-12.9 (p<0.01). Urinary Pyd also increased over time from 445.7+/-266.5 to 716.8+/-301.8 (p<0.01). In a linear regression model including gestational age and intervention, serum PICP increased significantly in the intervention group (regression coefficient 18.8+/-4.6, p=0.0001) while urinary Pyd did not differ between groups (regression coefficient=5.6+/-114.3, p=0.961). CONCLUSIONS: A combined massage and physical activity protocol improved bone formation (PICP) but did not affect bone resorption (Pyd). Pyd increased over time in both groups, possibly due to continuous bone resorption and Ca mobilization. 相似文献