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81.
INTRODUCTION : We recently found that DNA methylation of S100A2, spleen tyrosine kinase (SYK), and Stathmin-1 (STMN1) correlates with response to tamoxifen therapy in metastatic breast cancer. In this retrospective study, we investigated immunohistochemically whether these three markers are predictors of relapse in early breast cancer (EBC) patients treated with adjuvant tamoxifen alone. METHODS : Immunohistochemical staining was performed for S100A2, SYK and STMN1 on a tissue microarray containing ER-positive invasive breast carcinomas from a study cohort of 215 operable breast cancer patients, who underwent radical local therapy and who were treated with adjuvant tamoxifen monotherapy. Cox regression was used to correlate staining intensity of the three markers with main endpoints in our study; disease-free survival (DFS), and disease-specific survival (DSS). RESULTS : In univariate analysis, only STMN1 staining intensity strongly correlated with DFS (P = 0.014) and DSS (P = 0.002). In the groups of low and high STMN1 intensity, DFS was 84% and 63%, and DSS was 89% and 70%. STMN1 retained its prognostic value for DFS (P = 0.002) and DSS (<0.001) in the multivariate model together with lymph node status. We found also a trend to better DFS in patients with low STMN1 intensity in both lymph node-positive (P = 0.001) and -negative patients (P = 0.065). As the tumour cells did not express S100A2 (except in one case) the potential prognostic value of this marker was not evaluated. CONCLUSIONS : Staining intensity of STMN1, but not SYK, predicted outcome in our collective of ER- positive tamoxifen treated EBC patients.  相似文献   
82.
83.
Neuropeptide K (NPK), a member of the kassinin-like tachykinin family, is contained in the rat hypothalamus and is known to stimulate pituitary ACTH release. The intraperitoneal bolus administration of NPK dose-dependently enhanced corticosterone blood level not only in intact rats, but also in hypophysectomized/ACTH replaced animals. NPK did not affect corticosterone secretion of dispersed rat adrenocortical cells: however, it concentration-dependently raised basal corticosterone production by decapsulated adrenal quarters (including both cortical and medullary tissues). Minimal and maximal effective concentrations were 10−9 and 10−8 M, respectively. 10−8 M NPK potentiated corticosterone response of adrenal quarters elicited by 10−12 M ACTH, but not that evoked by higher concentrations of ACTH. The direct corticosterone secretagogue effect of 10−8 M NPK is annulled by 10−6 M α-helical-CRH or corticotropin-inhibiting peptide, competitive inhibitors of CRH and ACTH, respectively. In light of these findings, the hypothesis is advanced that NPK exerts a direct stimulatory action on adrenocortical secretion and that the mechanism underlying this effect of NPK may involve the activation of the intra-medullary CRH/ACTH system.  相似文献   
84.
We studied the growth-promoting effect of treatment with recombinant human growth hormone in 23 prepubertal children with Noonan syndrome, aged between 5. 4 and 14. 3 y, and all with a height < 1. 4 SD for Tanner standards. The growth response and skeletal maturation after 1 y of recombinant human growth hormone treatment (0. 15 U/kg/day given by daily injection) in the Noonan syndrome patients was compared with the auxological changes observed in a group of 17 girls with Turner syndrome with a comparable age and height deficit who were treated with recombinant human growth hormone in a similar way. During 1 y of treatment, the mean ± SD height velocity increased by 4. 0 ± 1. 6 cm/y in the Noonan syndrome group and by 3. 6 ± 1. 3 cm/y in the Turner syndrome group. Height SDS for chronological age in the Noonan syndrome group increased by 0. 53 ± 0. 46 ( p < 0. 001). In the Noonan syndrome patients the changes in height velocity were positively related to birthweight ( r = 0. 48, p < 0. 05). The changes in height velocity or height SDS were not related to the age, height deficit or a delay in bone age maturation at start of treatment. In neither the patients with Noonan syndrome nor Turner syndrome was an acceleration of bone maturation found. We conclude that treatment with recombinant human growth hormone in pre-pubertal NS patients induces an increase in height velocity and height SDS comparable to that observed in Turner syndrome girls.  相似文献   
85.
We measured the number of glucocorticoid receptors (GR) in cord blood lymphocytes and the binding affinity (Kd) in 15 term and in 20 preterm babies. Thirteen preterms of the latter group received prenatal steroid treatment. Seven preterms developed neonatal respiratory distress syndrome (NRDS). The number of GR and the Kd were similar in the term and preterm (with and without NRDS) babies. The maximum thymidine incorporation into DNA of cord blood lymphocytes from all preterms, with or without NRDS was suppressed when compared to that from term babies or adults. This could partly be explained by the antenatal steroid treatment. Sensitivity (ID50) of the lymphocytes for the inhibitory effect of dexamefhasone was the same in all groups. In this study on the number and function of GR in lymphocytes, we were unable to find a relation between the functionality of the GR and the development of NRDS.  相似文献   
86.
Prolonged sodium restriction was found to induce a notable hypertrophy of rat zona glomerulosa (ZG) cells and a significant rise in the basal plasma aldosterone concentration. Chronic prolactin administration significantly furthered the effects of sodium restriction. Dopamine infusion (3 mg/kg day for 7 days) did not apparently affect ZG morphology and function in the control rats, while it significantly counteracted the effects of sodium deprivation combined or not with prolactin administration. However, the action of dopamine was less intense in sodium-deprived rats treated with prolactin. These findings confirm the view that the dopaminergic system exerts a tonic inhibitory effect, modulated by the sodium balance, on the growth and secretory activity or rat ZG. Moreover, they suggest that the mechanism(s) underlying the antiadrenoglomerulotrophic action of dopamine in rats only partially involve(s) the well-known suppression of the hypophyseal release of prolactin.  相似文献   
87.
The effects of a long-term (7 days) administration of alpha-melanocyte-stimulating hormone (alpha-MSH) on the zona glomerulosa were investigated in "normal" rats and in animals in which the hypothalamic-hypophyseal-adrenal axis and the renin-angiotensin system had been pharmacologically interrupted. alpha-MSH caused a notable hypertrophy of the zona glomerulosa and its parenchymal cells, as well as a significant increase in the plasma concentration of aldosterone, in rats infused with dexamethasone, dexamethasone plus ACTH or captopril plus angiotensin II, but not in animals treated with captopril alone. These findings indicate that alpha-MSH is directly involved in the stimulation of the growth and steroidogenic capacity of rat zona glomerulosa, and that this action of alpha-MSH requires a normal level of circulating angiotensin II.  相似文献   
88.
BACKGROUND: Modern fertilization techniques can lead to unexpected ABO phenotypes in newborn infants and can raise questions as to maternity, paternity, and infant misidentification. Ovum transplantation can result in an infant with an ABO phenotype that is unexpected, given the birth mother's ABO type. STUDY DESIGN AND METHODS: A group AB, Rh- positive female infant was born to a group O, Rh-positive woman as a result of ovum transplantation. The case report is provided. RESULTS: The birth mother typed group O, Rh-positive both before and after delivery. The infant typed group AB, Rh-positive on cord blood and heelstick specimens. CONCLUSION: Ovum transplantation can result in newborns whose ABO phenotypes are unexpected, in relation to the birth mother's ABO type. To ensure patient privacy, such fertilization techniques may not be clearly documented in the delivery room chart. A complete obstetric history helps prevent repeat phlebotomies, expensive and unnecessary typing studies, and concern of the clinical staff with possible sample or infant misidentification.  相似文献   
89.
Orexins A and B are hypothalamic peptides that originate from the proteolytic cleavage of preproorexin and act through two subtypes of receptors, named OX1-R and OX2-R. OX1-R almost exclusively binds orexin-A, whereas OX2-R is nonselective for both orexins. We previously found that orexin-A, via the OX1-R, stimulates cortisol secretion from dispersed human adrenocortical cells. In this study, we demonstrate that six of eight cortisol-secreting adenomas expressed preproorexin mRNA, and seven of 10 adenomas contained measurable amounts of orexin-A but not orexin-B. Normal adrenal cortexes neither expressed preproorexin nor contained orexins. All adenomas expressed OX1-R and OX2-R mRNAs, and real-time PCR showed that the expression of both receptors was up-regulated in adenomas, compared with normal adrenal cortex. Orexin-A concentration-dependently raised basal cortisol secretion from freshly dispersed normal and adenomatous cells, minimal and maximal effective concentrations being 10(-10) and 10(-8) m, and the peptide efficacy (percent increase elicited by 10(-8) m orexin-A) was significantly higher in adenomas than in the normal adrenal cortex. Orexin-B was ineffective, thereby indicating that orexin secretagogue action is mediated by the OX1-R. In contrast, both orexins (10(-8) m) raised the proliferative activity of cultured normal and adenomatous cells, suggesting that this effect is mediated by OX2-R or both receptor subtypes. Collectively, our findings allow us to conclude that the orexin system is overexpressed in cortisol-secreting adenomas and suggest that orexin-A may act as an autocrine-paracrine regulator of the secretory activity and growth of some of these adrenal tumors.  相似文献   
90.
A possible autocrine role for interleukin-6 in two lymphoma cell lines   总被引:8,自引:1,他引:8  
Interleukin-6 (IL-6) is a growth factor with diverse biologic activity. Originally described as a T-cell product that enhances immunoglobulin (Ig) secretion in antigen-stimulated B cells, it also affects the growth of T cells, plasmacytomas, hybridomas, and hematopoietic stem cells. We report the expression and secretion of IL-6 by two lymphoma cell lines, OCI-LY3 and OCI-LY12. Addition of recombinant IL-6 stimulated their growth, whereas addition of polyclonal anti- recombinant IL-6 (anti-rIL-6) had a marked inhibitory effect on proliferation. These results suggest an autocrine role for IL-6 in the growth of these lymphoma cells in culture.  相似文献   
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