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101.
目的探讨乳腺浸润性导管癌中雌激素调节蛋白(PS2)的表达及其与雌激素受体(ER)、孕激素受体(PR)的关系。方法收集新疆医科大学附属肿瘤医院2008-2009年经病理确诊并行外科手术治疗的70例乳腺浸润性导管癌组织石蜡标本,采用免疫组化法检测PS2、ER、PR表达,分析PS2与ER、PR表达及临床病理因素的相关关系。结果 PS2、ER、PR阳性表达率分别为37.14%(26/70)、40.00%(28/70)、42.86%(30/70)。PS2在ER阳性和阴性病例中的阳性表达率分别为60.71%(17/28)和21.43%(9/42),两者差异有统计学意义(P<0.05)。PS2在PR阳性和阴性病例中的阳性表达率分别为66.67%(20/30)和15.00%(6/40),两者差异有统计学意义(P<0.05)。患者年龄、月经状态与PS2蛋白表达无明显关系(P>0.05),PS2表达与ER呈正相关(γs=0.35,P=0.014),PS2表达与PR呈正相关(γs=0.475,P=0.000),PS2表达与患者组织分级及淋巴结转移有关(P<0.05)。结论 PS2表达与ER、PR及淋巴结转移状况与组织分级临床因素有关。ER、PR、PS2综合检测对判定乳腺内分泌治疗效果及预后具有重要意义。  相似文献   
102.
Diet is the main source of cadmium (Cd) exposure. Gastrointestinal absorption increases during pregnancy. Cadmium accumulated in the placenta may interfere with nutrient transport to the foetus. Data on the potential of Cd to act as a steroid disruptor of pregnancy are limited. We evaluated the effects of oral Cd exposure during pregnancy on placental function in micronutrient transfer to the foetus and steroidogenesis in Wistar rats (regular 4‐day cyclers) that mated with unexposed males. Pregnant rats were randomly assigned to a Cd group exposed orally to 50 mg Cd l–1 (CdCl2xH2O dissolved in demineralized water), ≈7.5 mg Cd kg–1 a day, during 20 days of gestation and control (supplied with demineralized water). Non‐pregnant rats were treated under the same experimental conditions. On day 20, all of the rats were killed and samples were taken for element analyses (by electrothermal atomic absorption spectrometry). Progesterone and testosterone were measured in serum and placenta‐derived samples (by immunoenzymometric assay and/or enzyme‐linked immunosorbent assay). In the exposed rats, Cd increased in blood and organs, more in pregnant rats, and in placenta and foetus whereas zinc increased in liver. Iron decreased in maternal organs and in foetus, whereas zinc decreased in maternal kidney and placenta. Liver copper was lower and kidney copper higher in all pregnant vs. non‐pregnant rats. Steroids in serum and placenta did not change. In conclusion, oral Cd exposure during rat pregnancy does not affect progesterone and testosterone at term. Transplacental iron and zinc handover are disrupted, which may put at risk the maintenance of foetal nutrition and viability. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
103.
Abstract The objective of this study was to present clinical and radiological data of eight women with histologically proven lymphangioleiomyomatosis (LAM) diagnosed between 1984 and 1994, and to suggest a diagnostic strategy when LAM is suspected. A review of case reports, including results of biopsies, lung function and radiological procedures was undertaken. The mean age of the women at start of symptoms was 36 years, and the mean age at time of diagnosis 42 years. The most frequent presenting complaint was dyspnea, either in conjunction with pneumothorax (3), chylothorax (2) or on exertion (2). All patients had airflow limitation and markedly reduced gas transfer. Five patients had 16 episodes of pneumothorax. In seven patients multiple cysts were observed on the surface of the lung during thoracotomy while computerized tomography (CT) scans revealed numerous cysts evenly distributed throughout the lung parenchyma. The procedures that confirmed the diagnosis included transbronchial lung biopsy (4), open lung biopsy (2), thoracoscopy (1), thoracotomy (3) and autopsy (1). Three specimens had to be revised before the histological diagnosis was confirmed. It was concluded that the important clues to a diagnosis of LAM are recurrent episodes of pneumothoraces in fertile women, progressive air-flow limitation, markedly reduced gas transfer and characteristic findings on thoracic CT scans. A specific request to the pathologist to stain lung tissue specimens for smooth muscle cells is mandatory.  相似文献   
104.
A subset of human breast cancer cell lines exhibits aberrant DNA hypermethylation that is characterized by hyperactivity of the DNA methyltransferase enzymes, overexpression of DNMT3b, and concurrent methylation-dependent silencing of numerous epigenetic biomarker genes. The objective of this study was to determine if this aberrant DNA hypermethylation (i) is found in primary breast cancers, (ii) is associated with specific breast cancer molecular subtypes, and (iii) influences patient outcomes. Analysis of epigenetic biomarker genes (CDH1, CEACAM6, CST6, ESR1, GNA11, MUC1, MYB, SCNN1A, and TFF3) identified a gene expression signature characterized by reduced expression levels or loss of expression among a cohort of primary breast cancers. The breast cancers that express this gene expression signature are enriched for triple-negative subtypes — basal-like and claudin-low breast cancers. Methylation analysis of primary breast cancers showed extensive promoter hypermethylation of epigenetic biomarker genes among triple-negative breast cancers, compared to other breast cancer subclasses where promoter hypermethylation events were less frequent. Furthermore, triple-negative breast cancers either did not express or expressed significantly reduced levels of protein corresponding to methylation-sensitive biomarker gene products. Together, these findings suggest strongly that loss of epigenetic biomarker gene expression is frequently associated with gene promoter hypermethylation events. We propose that aberrant DNA hypermethylation is a common characteristic of triple-negative breast cancers and may represent a fundamental biological property of basal-like and claudin-low breast cancers. Kaplan–Meier analysis of relapse-free survival revealed a survival disadvantage for patients with breast cancers that exhibit aberrant DNA hypermethylation. Identification of this distinguishing trait among triple-negative breast cancers forms the basis for development of new rational therapies that target the epigenome in patients with basal-like and claudin-low breast cancers.  相似文献   
105.
Testosterone (T) and oestrogen are the main active steroid hormones in the male and female reproductive system respectively. In female rodents progesterone (P4), together with testosterone and oestrogen, has an essential role in the regulation of the oestrous cycle, which influences the prostate physiology through their oscillations. In this work we investigated how the male and female prostate gland of Mongolian gerbils responds to surgical castration at the start of puberty and what are the effects of T, oestradiol (E2) and P4 replacement, using both quantitative and qualitative methods. We also examined the location of the main steroid receptors present in the prostate. In the castrated animals of both sexes an intense glandular regression, along with disorganization of the stromal compartment, and abundant hyperplasia was observed. The replacement of P4 secured a mild recovery of the glandular morphology, inducing the growth of secretory cells and restoring the androgen receptor (AR) cells. The administration of P4 and E2 eliminated epithelial hyperplasia and intensified gland hypertrophy, favouring the emergence of prostatic intraepithelial neoplasia (PIN). In animals treated with T and P4, even though there are some inflammatory foci and other lesions, the prostate gland revealed morphology closer to that of control animals. In summary, through the administration of P4, we could demonstrate that this hormone has anabolic characteristics, promoting hyperplasia and hypertrophy, mainly in the epithelial compartment. When combined with E2 and T, there is an accentuation of glandular hypertrophy that interrupts the development of hyperplasia and ensures the presence of a less dysplastic glandular morphology.  相似文献   
106.
Estradiol (E2) and progesterone (P4) are steroid hormones important for the regulation of immune responses during pregnancy. Their increasing levels coincide with an improvement of T cell-mediated diseases such as multiple sclerosis (MS). Although immune-endocrine interactions are involved in this phenomenon, the relative contribution of hormones is not known. We here report a direct comparison of E2- and P4-mediated effects on human CD4+ T cells, key cells in immune regulation. T cells were stimulated to obtain different activation levels and exposed to a broad range of hormone concentrations. Activation level was assessed by CD69/CD25 expression by flow cytometry, and secreted proteins (n = 196) were measured in culture supernatants using proximity extension assay and electrochemiluminescence immunoassay. We found that in low activated cells, pregnancy-relevant E2 concentrations increased activation and the secretion of several immune- and inflammation-related proteins. P4, on the other hand, showed a biphasic pattern, where serum-related concentrations upregulated activation and protein secretion while placenta-relevant concentrations induced a prominent dampening irrespective of the initial activation level. Our results demonstrate the importance of P4 as a major hormone in the immune modulation of T cells during pregnancy and emphasize the need to further evaluate its potency in the treatment of diseases like MS.  相似文献   
107.
Circulating TFH (cTFH) cells express CXCR5, PD-1, and, when activated, ICOS, and release IL-21. According to the production of IFN-γ, IL-4, and IL-17 and expression of FoxP3, these cells are also classified as cTFH1, cTFH2, cTFH17, and cTFR cells, respectively. This CD4+T-cell subset is pivotal to efficient humoral immunity, and pregnancy appears to favor IgG production. Here, not only pregnancy amplified the in vivo production of anti-HBsAg IgG in HBV immunized women, but the frequency of cTFH cells was directly correlated with estradiol levels. In vitro, pregnancy-related dose of 17-β-estradiol (E2) directly increased the percentage of different cTFH subsets. While E2 and progesterone (P4) increased the proportion of differentiated TFH cells derived from naïve CD4+T-cells, only E2 amplified the release of IL-21 in those cell cultures. In addition, E2 and P4 increased the proportion of memory B cells and plasma cells, respectively. In SEB-activated B/TFH cell co-cultures, E2, in the presence of P4, increased the production of total IgG. Finally, among the hormones, P4 was stronger in upregulating the percentage of IL-10+TFR cells. Collectively, our findings suggested that E2 and P4 cooperate in the humoral immune response by favoring the expansion of different cTFH and B cell subsets.  相似文献   
108.
109.
目的 探讨孕酮(progesterone,PROG)对缺血/再灌注(ischemia-reperfusion,I/R)脑损伤大鼠的神经保护作用及其可能机制。方法 138只大鼠随机等分为假手术(Sham)组、大脑中动脉栓塞(middle cerebral artery occlusion,MCAO)组和PROG+MCAO组,分别采用Longa法和Morris水迷宫试验评估大鼠运动功能和认知功能;脑组织TTC染色法、磁共振波谱(magnetic resonance spectroscopy,MRS)法和Annexin V-FITC/PI双染法评估神经细胞损伤情况;ELISA法检测脑脊液ATP、IL-6、TNF-α和COX-2含量;Western blotting法检测脑组织P2X7R和NF-κB蛋白表达的变化。结果 与MCAO组相比,PROG+MCAO组大鼠Longa评分(第5~7天)和Morris水迷宫试验潜伏期(第4~7天)下降(P<0.05或P<0.01),而目标交叉次数增高(P<0.05);PROG+MCAO组大鼠NAA/Cr和Cho/Cr比值较MCAO组升高,脑梗死体积和细胞凋亡率较MCAO组明显降低(P<0.05);MCAO组脑脊液ATP、COX-2、TNF-α和IL-6的含量明显高于Sham组,PROG+MCAO组上述指标含量明显低于MCAO组(P<0.05);MCAO组脑组织P2X7R和NF-κB蛋白的表达水平高于Sham组,而其在PROG+MCAO组表达水平又明显低于MCAO组(P<0.05)。结论 PROG通过降低神经细胞凋亡率、减轻神经元损伤及髓鞘降解而改善I/R脑损伤大鼠运动和认知功能,这一保护作用与其抑制ATP-P2X7R信号通路密切相关。  相似文献   
110.
目的:研究来曲唑片和地屈孕酮片联合治疗不孕症的疗效及其对患者血清孕酮的影响。方法:选取在某院确诊为不孕症并接受治疗的患者100例作为研究对象,按照治疗方法的不同,将其均分为单一组和联合组两个组别。单一组患者在常规治疗基础上通过来曲唑片进行的单一治疗,联合组患者在对照组基础上通过地屈孕酮片进行治疗,对比两组患者治疗的效果及相关指标的变化。结果:联合组患者治疗的总有效率为90%,显著高于单一组患者的72%(P<0.05);联合组患者的排卵率、SP、E2、LH水平均有显著改善,且优于单一组患者(P<0.05)。结论:对于不孕症患者来说,相比于使用来曲唑片进行单一治疗,来曲唑片和地屈孕酮片联合治疗不仅可以有效提高治疗效果及妊娠率,而且可以更有效改善患者的血清孕酮等水平,因此值得推广。  相似文献   
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