全文获取类型
收费全文 | 18955篇 |
免费 | 1205篇 |
国内免费 | 200篇 |
专业分类
耳鼻咽喉 | 239篇 |
儿科学 | 637篇 |
妇产科学 | 456篇 |
基础医学 | 2522篇 |
口腔科学 | 217篇 |
临床医学 | 1505篇 |
内科学 | 3528篇 |
皮肤病学 | 335篇 |
神经病学 | 1395篇 |
特种医学 | 599篇 |
外国民族医学 | 1篇 |
外科学 | 2413篇 |
综合类 | 478篇 |
一般理论 | 23篇 |
预防医学 | 3020篇 |
眼科学 | 487篇 |
药学 | 1125篇 |
2篇 | |
中国医学 | 136篇 |
肿瘤学 | 1242篇 |
出版年
2024年 | 28篇 |
2023年 | 183篇 |
2022年 | 351篇 |
2021年 | 616篇 |
2020年 | 280篇 |
2019年 | 514篇 |
2018年 | 622篇 |
2017年 | 440篇 |
2016年 | 462篇 |
2015年 | 544篇 |
2014年 | 722篇 |
2013年 | 1020篇 |
2012年 | 1475篇 |
2011年 | 1520篇 |
2010年 | 905篇 |
2009年 | 716篇 |
2008年 | 1105篇 |
2007年 | 1186篇 |
2006年 | 1112篇 |
2005年 | 937篇 |
2004年 | 887篇 |
2003年 | 831篇 |
2002年 | 715篇 |
2001年 | 365篇 |
2000年 | 304篇 |
1999年 | 256篇 |
1998年 | 102篇 |
1997年 | 101篇 |
1996年 | 76篇 |
1995年 | 69篇 |
1994年 | 68篇 |
1993年 | 47篇 |
1992年 | 157篇 |
1991年 | 145篇 |
1990年 | 164篇 |
1989年 | 175篇 |
1988年 | 144篇 |
1987年 | 146篇 |
1986年 | 117篇 |
1985年 | 110篇 |
1984年 | 75篇 |
1983年 | 58篇 |
1982年 | 24篇 |
1981年 | 30篇 |
1980年 | 25篇 |
1979年 | 47篇 |
1975年 | 36篇 |
1974年 | 24篇 |
1973年 | 25篇 |
1972年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
101.
EPIDEMIOLOGIE DE L’HYPERTENSION ARTERIELLE EN TUNISIE.Etude Hammam Sousse/Sahloul Heart Study (HSHS)
Aicha Hamoudi Asma Ben Abdelaziz Sarra Melki Donia Ben Hassine Nabila Ben Rejeb Asma Omezzine Ali Bouslama Ahmed Ben Abdelaziz 《La Tunisie médicale》2022,100(2):167
Introduction: Tunisia is experiencing a double burden of morbidity, characterized by the explosion of cardiovascular diseases and their risk factors including arterial Hypertension. The objective of this study, based on the HSHS cohort (Hammam Sousse Sahloul Heart Study), was to determine the prevalence of hypertension in the general population and to identify its predisposing factors. Methods: HSHS is a cardiovascular health promotion initiative in the city of Hammam Sousse (Tunisia). The study was conducted via a random sample of households, using the WHO PEV technique, made up of 33 clusters, of 33 households each. All people aged 20 and over, included, benefited from a questionnaire, a physical examination and a biological assessment. The Systolic Blood Pressure (SBP) and the Diastolic Blood Pressure (DBP) were measured from the average of the last two measurements, by an OMRON type tensiometer, of suitable width. These prevalences were adjusted according to sex and age group, by their weighting coefficients in the general population, and they were accompanied by their 95% CIs. Binary logistic regression was conducted to identify independent factors associated with hypertension. Results: The study population was composed of 481 men (33.4%) and 960 women (66.6%), with an average age of 49.6±16.35 years in males (M) and 46.6±16.18 in females (F). In addition to the family history of hypertension, the sufficient weekly consumption of vegetables and fruits was low (M: 32.4%, F: 24.9%). The adjusted rate of hypertension in the adult study population was 32.5%, 95%CI[31.9-33.1] (M: 36.4%, 95%CI[35, 5-37.3]; F: 28.4%; 95% CI[27.6-29.2]), reaching in the age group of 60 years and above: M: 74.6% (95%CI[66.9-82.3], F: 82.7% (95%CI[73.8-83.6]) Multivariate analysis identified five independent factors significantly associated with hypertension: male sex (ORa=1.55 [1.18-2.03]), age over 40 years (ORa=6.54[4.70-9.11]), low level of schooling (ORa=1.80 [1.36-2.38]), low physical activity (ORa=1.42[1.07-1.88]) and high socio-economic level (ORa=1 .84 [1.30-2.63]). Conclusion: The HSHS study confirmed the high prevalence of hypertension, and the extent of its low detection and control. Hence the need for a universal approach to health promotion, oriented towards the general population, piloted by its local organizations, based on the adoption of a healthy lifestyle, and centered on physical activity. 相似文献
102.
Bouchra Asbani Yaovi Gagou Said Ben Moumen Jean-Luc Dellis Abdelilah Lahmar MBarek Amjoud Daoud Mezzane Mimoun El Marssi Brigita Rozic Zdravko Kutnjak 《Materials》2022,15(15)
Ferroelectric property that induces electrocaloric effect was investigated in Ba(GexTi1−x)O3 ceramics, known as BTGx. X-ray diffraction analysis shows pure perovskite phases in tetragonal symmetry compatible with the P4mm (No. 99) space group. Dielectric permittivity exhibits first-order ferroelectric-paraelectric phase transition, confirmed by specific heat measurements, similar to that observed in BaTiO3 (BTO) crystal. Curie temperature varies weakly as a function of Ge-content. Using the direct and indirect method, we confirmed that the adiabatic temperature change ΔT reached its higher value of 0.9 K under 8 kV/cm for the composition BTG6, corresponding to an electrocaloric responsivity ΔT/ΔE of 1.13 × 10−6 K.m/V. Such electrocaloric responsivity significantly exceeds those obtained so far in other barium titanate-based lead-free electrocaloric ceramic materials. Energy storage investigations show promising results: stored energy density of ~17 mJ/cm3 and an energy efficiency of ~88% in the composition BTG5. These results classify the studied materials as candidates for cooling devices and energy storage applications. 相似文献
103.
目的 研究乌鲁木齐地区非综合征性聋患者线粒体12S rRNA基因突变情况。方法 收集乌鲁木齐非综合征性聋患者标本609例,对其进行临床和分子遗传学评估。结果 12S rRNA基因突变分析共发现11个突变位点,已知的A1555G、961DelT、C1494T突变分别占2.96%,1.15%,0.16%。另外A1047G突变相关报道较少,A1585G突变未见相关报道。其他突变均为多态性位点。结论 线粒体12S rRNA突变是引起遗传性聋的重要因素,此次乌鲁木齐地区线粒体12S rRNA A1555G突变在聋病人群中的检出率与前期报道相比有所降低,可能与耳毒性药物使用量降低有关。A1047G与新发现的A1585G突变是否与聋相关,还需进一步研究。对筛查中阳性突变携带者及其母系家庭成员需告知氨基糖苷类抗生素使用风险,使其避免使用,逐步降低药物性聋的发生率。 相似文献
104.
105.
Timmermans A van Doorn LC Opmeer BC Kroeks MV Duk MJ Bouwmeester AM Kruitwagen RF Dijkhuizen FP Mol BW;Dutch Study in Postmenopausal Bleeding 《Obstetrics and gynecology》2008,111(1):137-143
OBJECTIVE: To estimate the incidence of recurrent postmenopausal bleeding among women who were diagnosed with an endometrial thickness greater than 4 mm. METHODS: We designed a prospective cohort study and included consecutive women not using hormone replacement therapy, presenting with a first episode of postmenopausal bleeding. We evaluated patients who had an endometrial thickness greater than 4 mm at transvaginal ultrasonography and benign endometrial sampling; presence of carcinoma was ruled out by office endometrial sampling, hysteroscopy, and/or dilation and curettage. Time until recurrent bleeding was measured, and diagnosis at recurrent bleeding was recorded. RESULTS: Among 318 patients who had an endometrial thickness greater than 4 mm, 222 patients had benign histology results and were available for follow-up. During follow-up, 47 (21%, 95% confidence interval 16-27%) patients had recurrent bleeding, with a median time to recurrent bleeding of 49 weeks (interquartile range 18 to 86 weeks). There was no difference with respect to recurrence rate between patients with polyp removal, patients with a normal hysteroscopy, and patients with office endometrial sampling alone at the initial workup. Two patients were diagnosed with atypical endometrial hyperplasia upon recurrent bleeding. CONCLUSION: The recurrence rate of postmenopausal bleeding in women with endometrial thickness greater than 4 mm is 20%. This recurrence rate is not related to incorporation of hysteroscopy or polyp removal at the initial workup. LEVEL OF EVIDENCE: II. 相似文献
106.
Altarescu G Renbaum P Brooks P B Margalioth EJ Ben Chetrit A Munter G Levy-Lahad E Eldar-Geva T 《Reproductive biomedicine online》2008,16(2):276-282
Achondroplasia, the most common form of dwarfism, is a candidate for preimplantation genetic diagnosis (PGD) because a single mutation accounts for almost all cases. Multiplex fluorescent assay including the common G380R mutation in the FGFR3 gene and eight close polymorphic markers was developed. First and second polar bodies (PB) were used for PGD analysis. An affected woman was treated with routine long-protocol ovarian stimulation and puncture. In the first PGD cycle, out of four fertilized oocytes, PB analysis revealed two mutant oocytes, one with total amplification failure of the maternal allele and one with inconclusive results. In the second PGD cycle, 14 oocytes were retrieved following a higher FSH dose and by performing oocyte retrieval and by placing the patient in the anti-Trendelenburg position using abdominal pressure to allow all follicles to be drained. Following PB analysis, two embryos containing the wild-type FGFR3 allele were transferred. This led to an uncomplicated pregnancy and delivery by Caesarean section at week 38 of a healthy boy, carrying the FGFR3 wild-type maternal allele. In conclusion, oocyte retrieval, while difficult in patients with achondroplasia, can be successfully performed. PB analysis is a reliable and sensitive method for PGD for maternal achondroplasia. 相似文献
107.
Meroditerpenoids and derivatives from the brown alga Cystoseira baccata and their antifouling properties 总被引:1,自引:0,他引:1
Mokrini R Mesaoud MB Daoudi M Hellio C Maréchal JP El Hattab M Ortalo-Magné A Piovetti L Culioli G 《Journal of natural products》2008,71(11):1806-1811
The brown alga Cystoseira baccata harvested along the Atlantic coasts of Morocco yielded seven new meroditerpenoids (1-4) and derivatives (5-7), whose chemical structures were elucidated mainly by 2D NMR and mass spectrometry. Surprisingly, for all these compounds, which possess a bicyclo[4.3.0]nonane ring system, a trans fusion of the bicyclic system was deduced by stereochemical studies even though such compounds isolated from Cystoseira species are known to have a typical cis orientation for the bridgehead methyls. The antifouling and antibacterial activities of compounds 1-5 and 7 were evaluated, as well as their toxicity toward nontarget species. Compounds 4, 5, and 7 showed antifouling activities against growth of microalgae, macroalgal settlement, and mussel phenoloxidase activity, while being nontoxic to larvae of sea urchins and oysters. 相似文献
108.
Kourda N Elloumi H Chérif K Ben Jilani S Zermani R 《Gynécologie, obstétrique & fertilité》2008,36(3):292-295
Brenner tumors account for only 1 to 2% of ovarian tumors. Proliferating Brenner tumors are characterized by an epithelial proliferation, resembling superficial well-differentiated urothelial carcinomas. A single 29-year-old patient was operated for an ovarian tumor. On gross examination, the tumor, which originated in the left ovary, was cystic multilocular and presented polyoid excrescences. Definitive histological exam showed a papillary proliferation lined by transitional cells without stroma infiltration. Mucinous cells lined some cavities. The diagnosis of proliferating Brenner tumor was made. Clinical and pathological characteristics of this rare entity will be discussed. 相似文献
109.
Lavery S El-Shawarby SA Moissidou M Taylor D Turner C Lavender B Trew G Margara R Winston R 《Human fertility (Cambridge, England)》2008,11(1):29-32
A 42-year-old female patient with history of secondary infertility was referred to our assisted conception unit for in vitro fertilization (IVF). Before her referral, she had two cycles of IVF at another centre; the first was unsuccessful and, after conceiving at the second attempt, the pregnancy was terminated at 14 weeks' gestation following a positive nuchal translucency scan and a diagnosis of trisomy 21 (Down syndrome) by a chorionic villous biopsy performed in the first trimester. The screening tests for trisomy 21 were offered to the patient in view of her advanced age. Subsequent karyotyping revealed that both partners had a normal chromosomal complement. Following genetic counselling, the couple were offered IVF treatment along with preimplantation genetic screening for trisomy 21. Four of the five embryos were suitable for biopsy, and one blastomere from each embryo was analyzed using fluorescent in situ hybridization for chromosome 21. The analysis revealed that two embryos had trisomy 21, one had monosomy 21, and only one embryo was diploid for chromosome 21. The single diploid embryo was transferred to the uterus on day 3, and resulted in an uneventful pregnancy and delivery of a healthy live-born male. 相似文献
110.