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131.
132.
研究了阿霉素羧甲基葡聚糖微球经肝动脉栓塞后的体内动力学过程、靶向特征和微球在体内的肝动脉栓塞效果。对犬进行肝动脉栓塞实验,并与肝动脉阿霉素(ADM)溶液灌注组进行对照。用HPLC荧光检测外周静脉和组织中药物浓度。结果表明:微球组峰浓度为0.558μg/ml,溶液组为1.013μg/ml;微球组的T1/2(α),T1/2(β)和MRT分别为溶液组的2.82,3.19和1.28倍。栓塞不同部位组织中ADM浓度,微球组分别是溶液组的8.0和9.1倍。动态血管造影表明:肝内外未见侧枝循环形成,栓塞作用持久,16周后微球仍未见完全降解。  相似文献   
133.
Coeliac disease is often under-diagnosed, particularly in cases which are atypical or asymptomatic. Objective : The aim of this study was to comprehensively assess the prevalence and clinical profile of adult coeliac disease in our community. Methods : One-hundred-and-thirteen subjects from the most recent MONICA (Multinational MONItoring of trends and determinants in CArdiovascular disease) 1991/2 survey with positive serology were followed up 3 years after initial screening and assessed by means of (i) a clinical questionnaire, (ii) screening blood tests, and (iii) jejunal biopsy. Results : Forty-six subjects (21 male, mean age 51 years) have been followed up to date. Prior to follow-up, two of these subjects were diagnosed as having coeliac disease. Ten (3 male, mean age 51 years) of 44 subjects had enteropathy. Three of these 10 subjects were relatively asymptomatic, 3 had folate deficiency and 3 had iron deficiency. Thus 12 of the 1823 initially screened had enteropathy consistent with coeliac disease. Conclusions : Coeliac disease is more prevalent than previous estimations and was found to be at least 1 in 152.  相似文献   
134.
朱曙东  赵琛  赵文君  赵升皓 《药学学报》1993,28(10):788-791
以μBondapak C18柱建立了赤霉素GA3的HPLC分析方法。反相HPLC梯度条件可使GA3与包括双键异构体GA1在内的其它同系物通过离子配对机制获得分离。此法操作简便,不需衍生化;分析快速,色谱全程仅15 min;检测灵敏,0.5μg即可准确定量;线性(r=0.999,n=5)、重复性(RSD<2%,n=4)均佳;结果准确。优越性全面超出各传统分析方法,可望成为赤霉素质量分析的标准方法。  相似文献   
135.
This study determined effects of follicle stimulating hormone (FSH) alone and in combination with tumour necrosis factor (TNF), on granulosa cells from small (5-10 mm diameter) and large (>10-25 mm) follicles during follicular and luteal phases of the cycle and during periods of acyclicity. Granulosa cells were collected from ovaries of premenopausal women undergoing oophorectomy. The cells were cultured with human FSH (2 ng/ml) and testosterone (1 microM) in the presence or absence of human TNF-alpha (20 ng/ml). Media were removed at 48 and 96 h after culture and progesterone, oestradiol and cAMP in media were measured by radioimmunoassays. FSH stimulated the accumulation of oestradiol from granulosa cells of small follicles during the follicular and luteal phases but not during acyclicity; and TNF reduced oestradiol accumulation in the presence of FSH. Interestingly, in granulosa cells from small follicles, progesterone and cAMP secretion increased in response to FSH and neither was affected by TNF. Thus, TNF specifically inhibited the conversion of testosterone to oestradiol in granulosa cells from small follicles. FSH stimulated oestradiol production by granulosa cells of large follicles obtained only during the follicular phase of the cycle and TNF inhibited the FSH-induced oestradiol secretion. Granulosa cells obtained from large follicles during the luteal phase and during acyclicity did not accumulate oestradiol in response to FSH. However, FSH increased progesterone and cAMP secretion by granulosa cells obtained from large follicles during the follicular and luteal phases. During the luteal phase alone, TNF in combination with FSH increased progesterone accumulation above that of FSH alone. FSH did not increase progesterone, oestradiol or cAMP secretion by granulosa cells obtained from large follicles during acyclicity. Thus, FSH increases progesterone, oestradiol and cAMP secretion by granulosa cells of small follicles during the follicular and luteal phases and TNF appears to inhibit FSH-induced oestradiol secretion specifically in those cells. In large follicles, FSH- stimulated granulosa cell secretion of oestradiol is limited to the follicular phase and this effect can be inhibited by TNF. In addition, when granulosa cells of large follicles do not increase oestradiol secretion in response to FSH, TNF stimulates progesterone secretion.   相似文献   
136.
Zhou  M; Yeager  AM; Smith  SD; Findley  HW 《Blood》1995,85(6):1608-1614
The wild-type (wt) p53 tumor suppressor gene is commonly inactivated in human malignancies, either by mutations or by loss of expression. An additional proposed mechanism for inactivation of wt-p53 is amplification of the murine double minute 2 (MDM2) gene and overexpression of the MDM2 protein, which binds to p53 and eliminates its tumor suppressor function. To investigate a potential role for MDM2 in the inactivation of wt-p53 in pediatric acute lymphoblastic leukemia (ALL), we examined the expression of MDM2 and p53, as well as the occurrence of p53 mutations and possible amplification of the MDM2 gene, in 19 pediatric ALL cell lines and one pediatric acute myelogenous leukemia (AML) line. Although we did not find significant amplification of the MDM2 gene in any of the leukemic lines, we detected overexpression of MDM2 in all 10 lines that expressed wt-p53. Of the 10 lines without overexpression of the MDM2 gene, six (including the AML line) did not express p53, and four expressed mutant p53 with single point mutations in exons 7 and 8. To determine whether primary leukemic cells showed a similar correlation, we analyzed the original cryopreserved leukemic bone marrow cells from seven patients from whom cell lines were established. We obtained similar results from both the primary leukemic cells and the corresponding cell lines: overexpression of MDM2 was present in primary cells that expressed wt-p53 but not in cells that lacked expression of wt-p53. These findings suggest an important role for MDM2 in the pathogenesis of pediatric ALL in which leukemic cells express wt-p53.  相似文献   
137.
138.
Background: Hepatitis B e antigen negative chronic hepatitis (e CHB) with detectable levels of hepatitis B virus DNA (HBV DNA) in serum has been reported in cases from Asia. This study was undertaken to find out prevalence eCHB and to correlate its presence with the clinical status and severity of the illness in cases of chronic liver disease in India.  相似文献   
139.

Background  

Phosphatidylethanolamine (PE) is a phospholipid which is biosynthesized into long chain N-acylethanolamines (NAEs) including oleoylethanolamide (OEA), a known inhibitor of food intake. The aim of this study was to investigate whether PE-containing lipids can also inhibit intake. This was a 4 treatment intervention where 18 male participants were given a high-fat test breakfast (2.5MJ, 53 en% fat) containing (i) high-phospholipid, high-PE lipid (ii) high-phospholipid, medium-PE lipid (iii) no-phospholipid, no-PE control lipid or (iv) water control, in a randomised cross-over. Visual analogue scales (VAS) were used to assess post-ingestive hunger and satiety, and energy intake (EI) was measured at an ad libitum lunch meal after 3.5hours.  相似文献   
140.
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