全文获取类型
收费全文 | 3167篇 |
免费 | 231篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 77篇 |
妇产科学 | 95篇 |
基础医学 | 401篇 |
口腔科学 | 116篇 |
临床医学 | 307篇 |
内科学 | 658篇 |
皮肤病学 | 117篇 |
神经病学 | 142篇 |
特种医学 | 99篇 |
外国民族医学 | 2篇 |
外科学 | 403篇 |
综合类 | 91篇 |
一般理论 | 2篇 |
预防医学 | 237篇 |
眼科学 | 53篇 |
药学 | 336篇 |
中国医学 | 33篇 |
肿瘤学 | 224篇 |
出版年
2024年 | 8篇 |
2023年 | 60篇 |
2022年 | 139篇 |
2021年 | 205篇 |
2020年 | 134篇 |
2019年 | 143篇 |
2018年 | 172篇 |
2017年 | 113篇 |
2016年 | 120篇 |
2015年 | 116篇 |
2014年 | 116篇 |
2013年 | 179篇 |
2012年 | 244篇 |
2011年 | 241篇 |
2010年 | 136篇 |
2009年 | 116篇 |
2008年 | 158篇 |
2007年 | 161篇 |
2006年 | 151篇 |
2005年 | 135篇 |
2004年 | 112篇 |
2003年 | 81篇 |
2002年 | 81篇 |
2001年 | 25篇 |
2000年 | 22篇 |
1999年 | 16篇 |
1998年 | 7篇 |
1997年 | 11篇 |
1996年 | 18篇 |
1995年 | 11篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 16篇 |
1990年 | 21篇 |
1989年 | 10篇 |
1988年 | 15篇 |
1987年 | 15篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1981年 | 6篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1974年 | 4篇 |
1973年 | 3篇 |
1971年 | 6篇 |
1969年 | 4篇 |
1967年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有3416条查询结果,搜索用时 0 毫秒
1.
2.
Mutasim A. Al-Ghazawi Maha S. Tutunji Salah M. AbuRuz 《European journal of clinical pharmacology》2010,66(2):159-163
Purpose
The main purpose of this work was to investigate the effect of pummelo juice on the pharmacokinetics of sildenafil after oral administration. 相似文献3.
Ihsan M Kenawi Barsoum N Barsoum Maha A Youssef 《European journal of pharmaceutical sciences》2005,26(3-4):341-348
IR, 1H NMR and mass spectrometric studies showed that cetirizine dihydrochloride interacted strongly with diclofenac sodium, even when the latter was metal bound, forming high molecular weight stable adducts. These new formations were unaffected by the possible steric constraints that may exist because of coordination yet did not have the power to break the formed coordinate bonds. The formed ionic bond took place between the carbonyl ion of diclofenac and the positively charged piperazine ring of cetirizine, forming a ternary compound in the case of the divalent metal clusters (Ca{(dic)2.2H2O}, Mg{(dic)2.2H2O}, Zn{(dic)2.2H2O}) and a quaternary one with the trivalent iron cluster (Fe{dic}3.3H2O). IR bands assigned to nuNH, deltaNH and nuC-N were shifted to lower frequency values in the spectra of the complexes; thus showing that coordination took place at the NH of the diphenylamine. TG and elemental analysis confirmed these results. 相似文献
4.
A young male patient with schistosomiasis and sarcoma of the urinary bladder is presented. Total cystectomy followed by radiotherapy was performed. The gross appearance, microscopic findings of the tumor and an outline of the disease are discussed. 相似文献
5.
Journal of Cutaneous Medicine and Surgery - 相似文献
6.
W M Pick J E Myers A R Sayed J Dhansay R L George A W Barday 《Suid-Afrikaanse tydskrif vir geneeskunde》1990,78(1):7-10
A prevalence study of hypertension in 8 family practices in low socio-economic areas of Cape Town examined 1,046 patients over the age of 15 years. The crude prevalence rate of hypertension was 20.26%. There was no significant sex difference. Systolic pressure, diastolic pressure and hypertensive status increased with age and body mass index (BMI). There were complex relationships with regard to sex in that the female sex was predictive of hypertensive status after the age of 45 years unexplained by differences in BMI. After adjusting for age, BMI and sex differences, widowhood, poor education, obesity, a family history of hypertension or stroke and a past history of hypertension were significant predictors of hypertensive status. Smoking status, occupational social class or property ownership were not predictive. Fifty-one per cent of hypertensive subjects were treated. Of those receiving treatment, 30% were controlled resulting in a control prevalence of only 18%. Younger male subjects were better controlled by treatment. A strong need for improved diagnosis and treatment of hypertension in family practice exists in this region. 相似文献
7.
8.
Our objectives were to study the types and incidence of thyroid follicular lesions coexisting with Hashimoto's thyroiditis (HT), the pitfalls in their cytodiagnosis, and the effect on management. All cases of HT diagnosed by fine-needle aspiration (FNA) and/or histology over a 7-yr period were retrospectively studied. HT coexisted with follicular adenoma (FA) in 6 cases, follicular variant of papillary carcinoma (FVPC) in 1 case, and goitrous nodule (GN) in 2 cases. The overall incidence rates of thyroid neoplasm and goitrous nodules coexistent with HT were 15% and 3.5%, respectively. A preoperative FNA diagnosis was available in 10 histologically proven cases of HT. A false-positive diagnosis of follicular neoplasm (FN) that led to unnecessary thyroidectomies was given in 3 cases. In 2 of these, the cytological diagnosis was HT with the possibility of coexisting FN, and in the third case, the cytological finding of HT was misinterpreted as FN. The main causes of these diagnostic pitfalls were the presence of hyperplastic follicular cells with nuclear pleomorphism, a paucity of lymphoid cells in burned-out HT, and lack of ones exposure. Nuclear pleomorphism was observed in none of the follicular adenomas. FNA diagnosed accurately the coexisting lesions in 6 cases; 3 FA, 1 FVPC, and 2 GN, but it did not sample HT. In one case, FNA diagnosed correctly both HT and the coexisting FA. Therefore, the presence of a coexistent neoplasm or goitrous nodule reduced the chances of sampling HT by 85.7%, with no false-negative results. Indeed, aspiration on and around the thyroid nodule helps in sampling HT. However, HT may dominate the smear and obscure neoplasia. This can be avoided if the procedure is performed by the pathologist and the aspiration is done on the nodule only. The overlapping cytological features of FN and HT were the main causes of false-positive results. This can be reduced by avoiding the diagnosis of FN in the presence of follicular-cell pleomorphism and/or moderate to excessive numbers of lymphoid cells, provided proper aspiration technique is maintained. 相似文献
9.
Hussain Z Stoakes L Massey V Diagre D Fitzgerald V El Sayed S Lannigan R 《Journal of clinical microbiology》2000,38(2):752-754
The National Committee for Clinical Laboratory Standards has recently changed the oxacillin breakpoint from >/=4 mg/liter to >/=0. 5 mg/liter to detect methicillin-resistant coagulase-negative staphylococci (CoNS) because the previous breakpoint lacked sensitivity. To determine the correlation between the new oxacillin breakpoint and the presence of the mecA gene, 493 CoNS of 11 species were tested. The presence of the mecA gene was determined by PCR, and oxacillin susceptibility was determined by the agar dilution method with Mueller-Hinton agar containing 2% NaCl and oxacillin (0. 125 to 4.0 mg/liter). The new breakpoint correctly classified all CoNS strains with mecA as methicillin resistant and strains of Staphylococcus epidermidis, S. haemolyticus, and S. hominis without mecA as methicillin susceptible. The breakpoint of >/=0.5 mg/liter was not specific for S. cohnii, S. lugdunensis, S. saprophyticus, S. warneri, and S. xylosus, in that it categorized 70 of 74 strains of these species without mecA (94.6%) as methicillin resistant. The results of this study indicate that the new oxacillin breakpoint accurately identifies strains of CoNS with mecA but is not specific for strains of certain species of CoNS without mecA. 相似文献
10.