全文获取类型
收费全文 | 2196篇 |
免费 | 155篇 |
国内免费 | 20篇 |
专业分类
儿科学 | 69篇 |
妇产科学 | 558篇 |
基础医学 | 360篇 |
口腔科学 | 5篇 |
临床医学 | 79篇 |
内科学 | 158篇 |
皮肤病学 | 9篇 |
神经病学 | 27篇 |
特种医学 | 10篇 |
外国民族医学 | 3篇 |
外科学 | 435篇 |
综合类 | 128篇 |
现状与发展 | 1篇 |
一般理论 | 1篇 |
预防医学 | 236篇 |
药学 | 88篇 |
中国医学 | 34篇 |
肿瘤学 | 170篇 |
出版年
2024年 | 11篇 |
2023年 | 42篇 |
2022年 | 76篇 |
2021年 | 110篇 |
2020年 | 88篇 |
2019年 | 111篇 |
2018年 | 94篇 |
2017年 | 82篇 |
2016年 | 78篇 |
2015年 | 64篇 |
2014年 | 112篇 |
2013年 | 211篇 |
2012年 | 70篇 |
2011年 | 104篇 |
2010年 | 85篇 |
2009年 | 84篇 |
2008年 | 67篇 |
2007年 | 78篇 |
2006年 | 92篇 |
2005年 | 79篇 |
2004年 | 65篇 |
2003年 | 47篇 |
2002年 | 59篇 |
2001年 | 42篇 |
2000年 | 50篇 |
1999年 | 26篇 |
1998年 | 17篇 |
1997年 | 28篇 |
1996年 | 33篇 |
1995年 | 19篇 |
1994年 | 19篇 |
1993年 | 18篇 |
1992年 | 17篇 |
1991年 | 17篇 |
1990年 | 17篇 |
1989年 | 16篇 |
1988年 | 20篇 |
1987年 | 21篇 |
1986年 | 11篇 |
1985年 | 16篇 |
1984年 | 11篇 |
1983年 | 11篇 |
1982年 | 8篇 |
1981年 | 5篇 |
1980年 | 8篇 |
1979年 | 15篇 |
1978年 | 6篇 |
1977年 | 2篇 |
1976年 | 5篇 |
1975年 | 3篇 |
排序方式: 共有2371条查询结果,搜索用时 17 毫秒
91.
Weintraub M Gross E Kadari A Ravitsky V Safran A Laufer N Revel A 《Pediatric blood & cancer》2007,48(1):4-9
Current therapy of childhood cancer makes long-term survival a realistic outcome for most patients. However, some treatment regimens entail a significant risk of infertility. No established method for preservation of female fertility is currently available. Ovarian cryopreservation is an experimental technology that is being offered with increasing frequency to women undergoing cancer therapy. It has not yet been reported in children and adolescent girls. The aim of this review is to stimulate discussion on the possibility of performing ovarian cryopreservation in pre-menarcheal girls in advance of therapies that may induce ovarian failure. We present a multi-disciplinary discussion of the risks and benefits associated with the procedure and propose guidelines for its implementation. We propose that all girls about to receive treatment that has a high risk for infertility be offered consultation about the possibility of ovarian cryopreservation. 相似文献
92.
Swan SH Liu F Overstreet JW Brazil C Skakkebaek NE 《Human reproduction (Oxford, England)》2007,22(6):1497-1502
BACKGROUND To look at possible long-term risks from anabolic steroids and other xenobiotics in beef, we examined men's semen quality in relation to their mother's self-reported beef consumption during pregnancy. METHODS: The study was carried out in five US cities between 1999 and 2005. We used regression analyses to examine semen parameters in 387 partners of pregnant women in relation to the amount of beef their mothers reported eating while pregnant. Mothers' beef consumption was also analysed in relation to the son's history of previous subfertility. RESULTS Sperm concentration was inversely related to mothers' beef meals per week (P = 0.041). In sons of "high beef consumers" (>7 beef meals/week), sperm concentration was 24.3% lower (P = 0.014) and the proportion of men with sperm concentration below 20 x 10(6)/ml was three times higher (17.7 versus 5.7%, P = 0.002) than in men whose mothers ate less beef. A history of previous subfertility was also more frequent among sons of "high beef consumers" (P = 0.015). Sperm concentration was not significantly related to mother's consumption of other meat or to the man's consumption of any meat. CONCLUSIONS These data suggest that maternal beef consumption, and possibly xenobiotics in beef, may alter a man's testicular development in utero and adversely affect his reproductive capacity. 相似文献
93.
Ramlau-Hansen CH Thulstrup AM Nohr EA Bonde JP Sørensen TI Olsen J 《Human reproduction (Oxford, England)》2007,22(6):1634-1637
BACKGROUND: Recent studies indicate that not only women's but also men's obesity has adverse effects on fecundity and since fecundity is a couple concept, we examined fecundity in relation to overweight and obesity of the couple. We also examined the association between weight changes and fecundity over time. METHODS: Between 1996 and 2002, 64 167 pregnant women enrolled in the Danish National Birth Cohort were interviewed during and 18 months after pregnancy. Information on body mass index (BMI) and waiting time to pregnancy (TTP) was available for 47 835 couples. RESULTS: Among men and women with a BMI of 18.5 kg/m(2) or more, we found a dose-response relationship between increasing BMI group and subfecundity (a TTP of more than 12 months): Odds ratio (OR) = 1.32 (95% CI: 1.26-1.37) for women and OR = 1.19 (95% CI: 1.14-1.24) for men. Among 2374 women with an initial BMI of 18.5 kg/m(2) or more, who participated more than once in the Danish National Birth Cohort, each kilogram increment in weight between the two pregnancies was associated with a 2.84 (95% CI: 1.33-4.35) days longer TTP. CONCLUSIONS: Couples have a high risk of being subfecund if they are both obese. 相似文献
94.
Natural transmission of a partial AZFb deletion of the Y chromosome over three generations: case report 总被引:6,自引:0,他引:6
The natural transmission of microdeletions of the Y chromosome is occasionally reported in the literature. Here we describe the natural transmission of a partial AZFb deletion over three generations. PCR amplification of several sequence tagged site markers in the three AZF regions of the Y chromosome was carried out in a patient with oligoasthenoteratozoospermia, his father and his naturally conceived son. The deletion was confirmed by Southern blotting. The propositum, his father and his son showed a probably identical, partial deletion of the distal part of the AZFb region, involving sY130 and sY143. The deletion was confirmed by Southern blotting using the sY130 probe. Partial AZFb microdeletions can be associated with moderate oligozoospermia allowing natural conception and therefore natural transmission of this genetic anomaly. Further studies are needed to define the pathogenetic significance of microdeletions involving sY130 and sY143. 相似文献
95.
Verhaak CM Smeenk JM Evers AW van Minnen A Kremer JA Kraaimaat FW 《Journal of behavioral medicine》2005,28(2):181-190
The predictive value of a comprehensive model with personality characteristics, stressor related cognitions, coping and social support was tested in a sample of 187 nonpregnant women. The emotional response to the unsuccessful treatment was predicted out of vulnerability factors assessed before the start of the treatment. The results indicated the importance of neuroticism as a vulnerability factor in emotional response to a severe stressor. They also underlined the importance of helplessness and marital dissatisfaction as additional risk factors, and acceptance and perceived social support as additional protective factors, in the development of anxiety and depression after a failed fertility treatment. From clinical point of view, these results suggest fertility-related cognitions and social support should receive attention when counselling women undergoing IVF or ICSI treatment. 相似文献
96.
Alexander Tuan Falk Cyrus Chargari Jean-Michel Hannoun-Lévi Caroline Adrados Julie Antomarchi Jean-Baptiste Guy 《Human fertility (Cambridge, England)》2016,19(2):85-89
Fertility is a major part of the global care of patients treated for cancer. A new discipline known as oncofertility has emerged in some countries. Although the relationship between chemotherapy and external radiotherapy and fertility has been studied and reported, there is only scarce data available on brachytherapy. This systematic review aims to report available knowledge on the impact of brachytherapy on fertility. Specific consultations should be considered before brachytherapy to inform patients about their fertility preservation options. 相似文献
97.
98.
A recombinant chromosome with Xp duplication and Xq deletion was found in two sisters with normal height and gonadal dysgenesis. Their mother and other four relatives, including a fertile male, carried an inv(X)(p22q22); the inverted X was randomly inactivated in one female carrier. The abnormal X chromosome showed inactivation in all the examined cells. This is the tenth report of a recombinant X chromosome. A review of the literature shows that: i) most female carriers of inv(X) are phenotypically normal and fertile; ii) recombinants having short-arm duplication and long-arm deletion are associated with ovarian failure and normal or tall stature, whereas the reciprocal recombinants are compatible with fertility but cause short stature; and (ü) except for one index case, all male carriers have a normal phenotype and 11 of them (from eight families) are of proven fertility. Moreover, no instance of male infertility has been documented. 相似文献
99.
Turner syndrome in a mother and daughter: r(X) and fertility 总被引:1,自引:0,他引:1
A patient with mosaic Turner syndrome and normal fertility had three documented pregnancies. She had a 45,X/46,X,r(X) karyotype and did not undergo spontaneous sexual maturation and menarche. Conception occurred while on hormone replacement therapy. Her first pregnancy ended with the birth of a normal 46,XY male, while the third pregnancy resulted in a healthy 45,X/46,X,r(X) female. A review of the literature reveals a myriad of theories to account for the variability of ovarian function in Turner syndrome, but, as yet, there are insufficient data to yield any conclusions. There appears to be an increased risk of trisomy 21 in the offspring of females with Turner syndrome. 相似文献
100.
Emilio Domínguez‐Salazar Gabriela Hurtado‐Alvarado Fernanda Medina‐Flores Javik Dorantes Oscar Gonzlez‐Flores Arturo Contis‐Montes de Oca Javier Velzquez‐Moctezuma Beatriz Gmez‐Gonzlez 《Journal of sleep research》2020,29(3)
Sleep loss increases blood–brain barrier permeability. As the blood–brain barrier and the blood–tissue barriers in the reproductive tract (blood–testis and blood–epididymis barriers) share common characteristics, we hypothesized that sleep restriction may also modify their barrier function. Previous reports showed that sleep loss decreased sperm viability and progressive fast mobility, which may be a consequence of altered blood–testis and blood–epididymis barrier. Therefore, we quantified changes in blood–testis and blood–epididymis barrier after sleep loss and related them to male fertility. Adult male Wistar rats were sleep restricted using the multiple‐platform technique in a protocol of 20 hr daily sleep deprivation plus 4 hr of sleep recovery in the home‐cage. At the 10th day, barrier permeability assays were performed with Na‐fluorescein, 10 kDa Cascade blue‐dextrans and Evans blue, and the expression of tight junction proteins, actin and androgen receptor was quantified. At the 10th day of sleep restriction and after sleep recovery days 1–7, males were placed with sexually receptive females, sexual behaviour was tested, and the percentage of pregnancies was calculated. Sleep restriction increased the barrier permeability to low‐ and high‐molecular‐weight tracers, and decreased the expression of tight junction proteins, actin and androgen receptor. Concomitantly, sleep restriction reduced the percentage of ejaculating males and the number of pregnancies. Sleep recovery for 2–3 days progressively re‐established fertility, as indicated by a higher percentage of ejaculating males and impregnated females. In conclusion, chronic sleep loss alters fertility concomitantly with the disruption of the blood–tissue barriers at the reproductive tract, the mechanism involves androgen signalling. 相似文献