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81.
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Citalopram, a selective serotonin reuptake inhibitor (SSRI), is frequently used in the treatment of major depressive disorders. In addition to its antidepressant features, citalopram shows some anticonvulsive properties at lower doses, whereas higher doses, ingested in cases of suicide, have been associated with seizures. Moreover, some reports support the enhancing effect of morphine on different responses of SSRIs such as analgesic and anticonvulsant properties. Although the exact mechanisms of these additive effects are not yet fully understood, 5-HT(3) receptor has recently been shown to play an important role in the central effects of SSRIs and morphine. In this regard, we used a model of clonic seizures induced by pentylenetetrazole (PTZ) in male NMRI mice to investigate whether morphine and citalopram exhibit additive anticonvulsant effects and, if so, whether this effect is mediated through modulation of 5-HT(3) receptors. In our study, citalopram at lower doses (0.5 and 1 mg/kg, ip) significantly increased the seizure threshold (P<0.01) and at a higher dose (50 mg/kg) had proconvulsive effects. Moreover, morphine at low and noneffective doses had additive effects on the anticonvulsive properties of citalopram. This additive effect was prevented by pretreatment with low and noneffective doses of tropisetron (a 5-HT(3) receptor antagonist) and augmented by 1-(m-chlorophenyl)-biguanide (mCPBG, a 5-HT(3) receptor agonist). Moreover, low doses of morphine (0.1 and 0.5 mg/kg) alone or in combination with potent doses of 5-HT(3) receptor agonist or antagonist could not alter the proconvulsive properties of citalopram at higher dose (50 mg/kg), ruling out the contribution of 5-HT(3) to this effect. In summary, our findings demonstrate that 5-HT(3) receptor mediates the additive anticonvulsant properties of morphine and low-dose citalopram. This could constitute a new approach to augmenting the efficacy and curtailing the adverse effects of citalopram.  相似文献   
83.
The aim of this study was to compare the bond strengths of three self-etching materials during one year of storage. Clearfil SE Bond (SE), Clearfil Protect Bond (PB), and Clearfil Tri-S Bond (TS) were used for bonding to dentin and enamel according to manufacturer's instructions. Microshear bond strength values were measured after 24 hours, six months, and one year. Two-way ANOVA showed that the interaction of material type and storage time was significant for dentin. At baseline, SE had the highest bond strength to dentin. There were no significant changes in bond strength for each material during the storage period, except for PB which showed increased bond strength to dentin after one year. All materials performed reliably after one year. However, the antibacterial and fluoride-releasing effects of PB would further contribute to the long-term clinical benefits of this material.  相似文献   
84.
PURPOSE: To study risk-based preventive practice among Iranian dentists. MATERIALS AND METHODS: A questionnaire survey was conducted at two annual dental meetings in 2004 and 2005 in Tehran. Using a five-point Likert scale, respondents indicated their level of agreement with taking preventive measures including oral hygiene, use of fluoride, diet and dental check-up for a high- and a low-risk (HR and LR, respectively) hypothetical patient case. Respondent's smoking and activity in smoking cessation were enquired about as well. Of 1033 responding dentists, 980 (64% men) were eligible for this study. Statistical evaluation was by the chi-square test and logistic regression. RESULTS: The top four of the eight measures were instructions on tooth brushing and flossing, advice related to fluoridated toothpaste, and regular dental check-ups, with the choice 'fully agree' being more prevalent for the HR (74%-58%) than for the LR case (59%-41%). For the HR case, 45% of the respondents fully agreed with applying chair-side tooth cleaning, 41% with advice on diet modification, and 38% with advice on home-use of sodium fluoride mouthwash. Of all respondents, 76% were nonsmokers and 56% reported that they always recommend their smoking patients to quit. Female gender and activity in professional reading were associated with higher levels of agreement for applying preventive measures to the HR case. Non-smoking was the strongest explanatory factor (OR = 3.6, 95% CI = 2.6-5.1) of dentist's higher involvement in smoking cessation. CONCLUSION: Risk-based preventive dental care should be emphasised and applied in order to maximise efficient use of resources.  相似文献   
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Aim of this study is to determine the risk of adverse pregnancy outcome by maternal serum alpha-fetoprotein (MSAFP) level. We followed 295 pregnant women from MSAFP screening in the 14th to 22th week of gestation until the end of pregnancy and information on pregnancy outcome have been recorded in questionnaires. Of 295 pregnant women, 270 had term labor and 25 had preterm labor. The frequencies of pregnancy outcomes were as following: 3 (1.01%) stillbirths, 25 (8.47%) preterm labor, and 10 (3.4%) preterm rupture of membranous (PROM), 15 (5.1%) pre-eclampsia, 23 (7.8%) oligohydramnious, and 1 (0.33%) miscarriage. The mean of preterm labor was significantly associated with the higher level of MSAFP (P = 0.021). The mean was 55.1 ng/cc in preterm labor and 41.1 ng/cc in term labor. Also, second trimester MSAFP levels were higher in women with pre-eclampsia (P < 0.001). The significant association was found between higher level of MSAFP with oligohydramnious (P < 0.001) and low birth weight (P < 0.001). Pregnancies with an elevated MSAFP level are associated with adverse obstetric outcomes and need more prenatal care.  相似文献   
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Objective

This clinical trial compared the effect of a dual trigger treatment (combination of gonadotropin-releasing hormone (GnRH) agonist and human chorionic gonadotropin (hCG) and hCG alone on oocyte quality and metaphase II oocytes’ number.

Methods

It was done on infertile couples who were undergoing intracytoplasmic sperm injection with GnRH-antagonist cycles in two infertility centers of Tehran. The main outcome measures were metaphase II oocytes’ number, clinical pregnancy, abortion, and implantation rates per cycle.

Results

A total of 126 normal responder women who were considered for in vitro fertilization were equally divided into two groups: control (hCG trigger) and investigation (dual trigger) groups. The control group received the hCG trigger (10,000?IU) and the investigation group received the dual trigger (0.2?mg of Triptoreline plus 5000?IU of hCG). The metaphase II oocytes’ numbers, rates of clinical pregnancy, abortion and implantation were not significantly different between the two groups (P?=?0.42, 0.70, 0.77, 0.80, respectively). Good quality embryos was significantly higher in the dual trigger group (P?=?0.04).

Conclusion

Final oocyte maturation with dual trigger improves the number of good quality embryos in normal responder women. Further research with larger sample size is needed to characterize the effect on oocyte quality and pregnancy rate.  相似文献   
90.

Objectives

Sertoli cells effect the fate map of spermatogonial stem cells (SSCs) to self-renew via providing the special microenvironments. Maintenance of proliferation and self-renewal activity of SSCs may be usable as a therapeutic strategy, leads to increase the recovery of male fertility. This research was aimed to evaluate the effect of mouse sertoli cells on spermatogonia stem cells proliferation and the expression pattern of stemness markers.

Methods

Spermatogonia stem cells were collected from neonatal mouse testis using a two-step mechanical and enzymatic digestion. SSCs were cultured in three groups: The first group or co-culture group consists of spermatogonia and sertoli cells that were cultured together. The control group, only spermatogonial cells and the group no. 3 included spermatogonial cells in the presence of GDNF. The colony formation of mentioned groups, was monitored during one month in culture. Identification of the colonies, was confirmed using PLZF and Oct4 immunostaining. Spermatogonial stemness genes includes; Stra8, mvh and piwill2 were analyzed by RT-PCR.

Results

In the co-culture group, cells proliferated rapidly and many colonies were appeared whereas they were rarely formed in the control groups. Colonies were exhibited alkaline phosphatesase activity and were immunopositive to Oct4 and PLZF, strongly. The gene expression of srta8, mvh and piwill2, in SSCs that were cultivated with sertoli cells, were greater significantly than other control groups.

Conclusion

It is concluded that co-culture of SSCs with sertoli cells prepares conditions which leads to efficient proliferation and maintenance of stemness condition of SSCs, that is usable as a therapeutic approach for treatment of male fertility.  相似文献   
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