全文获取类型
收费全文 | 232篇 |
免费 | 19篇 |
国内免费 | 5篇 |
专业分类
儿科学 | 10篇 |
妇产科学 | 1篇 |
基础医学 | 30篇 |
口腔科学 | 3篇 |
临床医学 | 22篇 |
内科学 | 52篇 |
皮肤病学 | 6篇 |
神经病学 | 7篇 |
特种医学 | 49篇 |
外科学 | 3篇 |
综合类 | 3篇 |
预防医学 | 49篇 |
眼科学 | 2篇 |
药学 | 14篇 |
肿瘤学 | 5篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 6篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 9篇 |
2014年 | 7篇 |
2013年 | 17篇 |
2012年 | 8篇 |
2011年 | 7篇 |
2010年 | 13篇 |
2009年 | 3篇 |
2008年 | 8篇 |
2007年 | 4篇 |
2006年 | 11篇 |
2005年 | 6篇 |
2004年 | 2篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 15篇 |
1997年 | 8篇 |
1996年 | 14篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 9篇 |
1976年 | 2篇 |
1975年 | 2篇 |
排序方式: 共有256条查询结果,搜索用时 0 毫秒
41.
Th. G. M. Sandfort U. Clement J. Knobel R. Keet E. M. M. de Vroome 《Clinical psychology & psychotherapy》1995,2(4):220-226
This study explores determinants of unsafe sex, specifically in HIV-infected gay men. It is assumed that safe sex in HIV-positive men is determined by other factors than in men with an unknown or negative serostatus. For HIV-positive men it is much less an issue of protecting oneself, and more so an issue of protecting the other. It is hypothesized that for HIV-positive men, practising safe and unsafe sex is the outcome of a coping process, in which the stress of being infected is mediated by several factors, potentially resulting in a tendency to compulsive sexual behaviour (sexualization). A path analytic test supports the theoretical model. However, sexualization, especially the tendency to have sex to make oneself feel better, is only related to the number of sex partners one has had and not to having practised unsafe sex. This may imply that practising safe and unsafe sex should be much more understood from an interpersonal than an intrapersonal perspective. 相似文献
42.
43.
This randomized double-blind placebo-controlled study was initiated to analyze the behavior of epididymis, processus vaginalis and testicular descent in cryptorchid boys treated with a low dose (20 g) of a luteinizing hormone-releasing hormone analogue (Buserelin), administered daily, as a nasal spray, for a short period (28 days). Fifty-nine true cryptorchid boys were randomly assigned to 3 groups: buserelin, treatment [22], surgical treatment [18] or placebo control group [19]. The 3 groups of patients were similar before treatment in regard to testicular position, chronological and bone age, height and weight, luteinizing hormone, follicle-stimulating hormone, testosterone, penile size and the volume of the contralateral descended testis. None of the patients had retractile testes. Buserelin significantly induced testicular descent compared to the boys treated with a placebo (P<0.01). A normal epididymis was found more often in boys with successful descent (P<0.003). A closed processus vaginalis was also more frequently observed in the group treated with buserelin than in surgically treated one (P<0.05). In conclusion, buserelin was capable of inducing testicular descent besides provoking further development of the epididymis and closing the processus vaginalis. 相似文献
44.
Cooper TG Hellenkemper B 《国外医学(计划生育.生殖健康分册)》2010,29(3):221-224
本研究的目的是提高用过氧化物酶试验检测精液中的白细胞时所得的圆形细胞数量的精确度。精液样本的圆形细胞浓度在(0.6~6)×10^6/mL之间,降低精液的稀释度,增加被测悬浮液的体积。1+5(1:6)的稀释度适合于测量过氧化物酶活性,并能为细胞检测提供足够清晰的背景。在该稀释度下,测定Neubauer-改良精子计数板两边所有18个网格中的细胞数量,额定细胞浓度为(1.9~3.3)×10^6/mL的10个样本中只有3个样本的圆形细胞数/〉400个。由于更低浓度的精子稀释液不适合测定圆形细胞或其过氧化物酶反应产物,所以无法精确测量(抽样误差5%)参考下限值(1×10^6/mL)。结果表明,正是由于测定精液中的10个样本中圆形细胞很难精确到1×10^6/mL,所以白细胞精液症临界值的确定一直存在诸多分歧。因此需要建立一些统计学上合理的参考限。 相似文献
45.
MBC Simelane OA Lawal TG Djarova CT Musabayane M Singh AR Opoku 《African journal of traditional, complementary, and alternative medicines》2012,9(4):561-573
Gunnera perpensa L. (Gunneraceae) is a medicinal plant used by Zulu traditional healers to stimulate milk production. The effect of an aqueous extract of the rhizome of the plant on milk production in rats was investigated. Female lactating rats that received oral doses of the extract of G.perpensa significantly (p<0.05) produced more milk than controls. The plant extract did not however, significantly influence the levels of prolactin, growth hormone, progesterone, cortisol, ALT, AST and albumin in the blood. The mammary glands of rats treated with the extract showed lobuloalveolar development. The extract (0.8 µg/ml) was also found to stimulate the contraction of the uterus and inhibit (23%) acetylcholinesterase activity. The cytotoxicity of the extract (LC50) to two human cell lines (HEK293 and HepG2) was 279.43 µg/ml and 222.33µg/ml, respectively. It is inferred that the plant extract exerts its activity on milk production and secretion by stimulating lobuloalveolar cell development and the contraction of myoepithelial cells in the alveoli. It is concluded that Gunnera perpensa contains constituents with lactogenic activity that apparently contribute to its effectiveness in folk medicine. 相似文献
46.
Dopa-responsive dystonia in British patients: new mutations of the GTP- cyclohydrolase I gene and evidence for genetic heterogeneity 总被引:4,自引:0,他引:4
Bandmann O; Nygaard TG; Surtees R; Marsden CD; Wood NW; Harding AE 《Human molecular genetics》1996,5(3):403-406
Dopa-responsive dystonia (DRD) was originally described in a series of
Japanese patients, but is now increasingly recognized in other countries.
Recently the GTP cyclohydrolase I (GTPCH) gene was isolated as the first
causative gene for dopa-responsive dystonia (DRD). Mutations were
identified in three Japanese families with autosomal dominantly inherited
DRD and in one sporadic Japanese patient. Characterisation of the
exon-intron boundaries of this gene has now allowed the analysis of
mutations at the level of genomic DNA. Amplifying all six exons, we
analyzed the GTPCH gene in nine British families with 33 affected family
members and in three sporadic cases and found six new mutations. Only point
mutations were found, causing a stop codon in one family and an amino acid
change in highly conserved regions of the gene in a further four families
and in one sporadic case. None of these mutations were detected more than
once and none of the mutations previously described were found in our
patients. No mutations were identified in four families and in two sporadic
cases.
相似文献
47.
48.
LDE Wijnberger TG Krediet J Egberts F van Bel 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(5):569-572
In a study of endogenous nitric oxide production in growth-retarded, very preterm newborns (<32 wk GA), urinary NOx/creatinine ratio and plasma guanosine 3',5'-cyclic monophosphate levels were determined during the early neonatal period. Newborns were divided into three groups: appropriate-for-gestational-age (AGA, n = 19), moderately small-for-gestational-age (SGA, n = 13) and severely SGA (n = 6) infants. Severely SGA infants showed significant higher values of nitric oxide derivatives during the first 24 h of life compared with the other groups. CONCLUSION: An increased NO production is found in SGA infants during the first 24 h after birth. This may reflect an increased intrauterine nitric oxide production in the feto-placental circulation found in cases with intrauterine growth retardation, 相似文献
49.
血小板激活因子对大鼠脑血管通透性的影响及药物的保护作用 总被引:1,自引:0,他引:1
颈内动脉注射血小板激活因子(PAF),再给伊文思蓝,可见脑实质染色程度加深,而颈内动脉只注射伊文思蓝,脑实质未见染色。而我们合成的新药SZ-1可剂量依赖性地抑制PAF诱导的脑实质伊文思蓝染色程度的加深。在体外培养的脑微血管平滑肌细胞上,PAF能显著刺激~(14)-花生四烯酸的释放,而SZ-1能剂量依赖性地抑制这种释放,提示PAF在脑内产生的损害除与其他因素相关外,还与其刺激花生四烯酸释放有密切关系,SZ-1对PAF引起的脑部损害有保护作用。 相似文献
50.
Mirco Sandfort Jrg B Hans Martin A Fischer Felix Reichert Martina Cremanns Jessica Eisfeld Yvonne Pfeifer Annika Heck Tim Eckmanns Guido Werner Sren Gatermann Sebastian Haller Niels Pfennigwerth 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(50)
In 2022, German surveillance systems observed rapidly increasing numbers of NDM-1- and NDM-1/OXA-48-producing Klebsiella pneumoniae, which may in part reflect recurring pre-pandemic trends. Among these cases, however, a presence in Ukraine before diagnosis was frequently reported. Whole genome sequencing of 200 isolates showed a high prevalence of sequence types ST147, ST307, ST395 and ST23, including clusters corresponding to clonal dissemination and suggesting onward transmission in Germany. Screening and isolation of patients from Ukraine may help avoid onward transmission. 相似文献