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91.
A life of pelvic pain 总被引:4,自引:0,他引:4
Berkley KJ 《Physiology & behavior》2005,86(3):272-280
Pelvic pain associated with menstruation, i.e., dysmenorrhea, is a chronic pelvic pain that not only interferes with a woman's wellbeing for a large part of her life but also often co-occurs with other chronic painful conditions such as interstitial cystitis and irritable bowel syndrome and others. Little has been known about mechanisms underlying these chronic pelvic pains. This paper reviews 37 years of research in my laboratory at Florida State University on such mechanisms. Our research, mostly on rats, has contributed to the following findings: (1) Female reproductive organs are innervated in a topographic fashion by afferents in the pelvic (vagina/cervix) and hypogastric (cervix/uterine horn) nerves. (2) The input contributes to uterine and vaginal perceptions (nociception) that are modified by reproductive status. (3) Throughout the CNS, neurons responsive to stimulation of the reproductive tract also respond to stimulation of skin and other internal organs, in a manner modifiable by reproductive status and peripheral pathophysiology. (4) This dynamic physiological convergence may reflect extensive anatomical divergence of and interconnections between pathways entering the CNS via gateways through the spinal cord, dorsal column nuclei, and solitary nucleus. (5) The convergence also indicates the existence of extensive cross-system, viscero-visceral interactions within the CNS, that, while organized for coherent bodily functioning, serves as a substrate by which pathophysiology in one organ can influence physiology and responses to pathophysiology in other organs. (6) Some cross-system effects observed so far include: (a) Bladder inflammation reduces the rate of uterine contractions and the effects of drugs on the uterus. (b) Colon inflammation produces signs of inflammation in the otherwise healthy bladder and uterus. (c) A surgical model of endometriosis produces vaginal hyperalgesia, exacerbates pain behaviors induced by a ureteral stone, and reduces volume voiding thresholds if the bladder. These cross-system effects, which likely involve CNS mechanisms, likely also underlie co-occurrence of painful clinical conditions. Research continues on details of these mechanisms and their relevance for clinical diagnosis and therapy. None of this work could have been done without collegial support of colleagues and technical staff at Florida State University. 相似文献
92.
AbstractGroup B Streptococcus (GBS) is the leading cause of neonatal disease worldwide, and invasive disease in adults is becoming more prevalent. Currently, some countries adopt an intrapartum antibiotic prophylaxis regime to help prevent the transmission of GBS from mother to neonate during delivery. This precaution has reduced the incidence of GBS-associated early-onset disease; however, rates of late-onset disease and stillbirths associated with GBS infections remain unchanged. GBS is still recognized as being universally susceptible to beta-lactam antibiotics; however, there have been reports of reduced susceptibility to beta-lactams, including penicillin, in some countries. Resistance to second-line antibiotics, such as erythromycin and clindamycin, remains high amongst GBS, with several countries noting increased resistance rates in recent years. Moreover, resistance to other antibiotic classes, such as fluoroquinolones and aminoglycosides, also continues to rise. In instances where patients are allergic to penicillin and second-line antibiotics are ineffective, vancomycin is administered. While vancomycin, a last resort antibiotic, still remains largely effective, there have been two documented cases of vancomycin resistance in GBS. This review provides a comprehensive analysis of the prevalence of antibiotic resistance in GBS and outlines the specific resistance mechanisms identified in GBS isolates to date. 相似文献
93.
Phoomphut Sangaphunchai Ian Todd Lucy C. Fairclough 《Clinical and experimental allergy》2020,50(3):291-307
Asthma is a chronic, recurrent and incurable allergy‐related respiratory disease characterized by inflammation, bronchial hyperresponsiveness and narrowing of the airways. Extracellular vesicles (EVs) are a universal feature of cellular function and can be detected in different bodily fluids. Recent evidence has shown the possibility of using EVs in understanding the pathogenesis of asthma, including their potential as diagnostic and therapeutic tools. Studies have reported that EVs released from key cells involved in asthma can induce priming and activation of other asthma‐associated cells. A literature review was conducted on all current research regarding the role and function of EVs in the pathogenesis of asthma via the PRISMA statement method. An electronic search was performed using EMBASE and PubMed through to November 2018. The EMBASE search returned 76 papers, while the PubMed search returned 211 papers. Following duplicate removal, titles and abstracts were screened for eligibility with a total of 34 studies included in the final qualitative analysis. The review found evidence of association between the presence of EVs and physiological changes characteristic of asthma, suggesting that EVs are involved in the pathogenesis, with the weight of evidence presently favouring deleterious effects of EVs in asthma. Numerous studies highlighted differences in exosomal contents between EVs of healthy and asthmatic individuals, which could be employed as potential diagnostic markers. In some circumstances, EVs were also found to be suppressive to disease, but more often promote inflammation and airway remodelling. In conclusion, EVs hold immense potential in understanding the pathophysiology of asthma, and as diagnostic and therapeutic markers. While more research is needed for definitive conclusions and their application in medical practice, the literature presented in this review should encourage further research and discovery within the field of EVs and asthma. 相似文献
94.
Allergic rhinitis (AR) is an upper airway disease with high prevalence in the world, and therefore needs to be thoroughly investigated and treated accordingly. Although the mechanisms underlying the pathology and treatment of AR have been widely studied, many aspects of AR are still unclear and warrant further investigations. The purpose of the present review was therefore to report recently published papers, which highlight the novel mechanisms and treatments of AR. These include role of environment, important proteins and cells, and some other factors in the pathogenesis of AR; as well as the role of immunotherapy and biologics in the treatment of AR. 相似文献
95.
I. Simonitsch C. W. Kopp I. Mosberger T. Radaszkiewicz B. Volc-Platzer 《Virchows Archiv : an international journal of pathology》1996,427(5):477-481
The cutaneous lymphocyte associated antigen (CLA) recognized by the monoclonal antibody (moAb) HECA-452 plays a major role in the homing of lymphocyte subpopulations to the skin by binding to E-selectin on dermal microvessels. The factors responsible for the immigration of Langerhans cells (LC) and their precursors into the skin are still unknown, but because normal resting LC are also capable of expressing CLA, the antigen was proposed as a candidate LC-homing structure. To gain insight into these mechanisms, the expression of HECA-452 on neoplastic LC within and outside the skin was investigated in paraffin-embedded sections from 44 patients with localized and disseminated forms of Langerhans cell histiocytosis (LCH) presenting with proliferating cells positive for CD45, CD1a, S100 and HLADR. Irrespective of the clinical presentation or the type of organ involved, HECA-452-positive LC were detected in all biopsies tested (range 5->90%). The most prominent HECA-452 reactivity was observed in skin lesions and in areas with accumulations of eosinophilic granulocytes. Our data provide evidence for a heterogeneous expression of sLex/sLea structures in various stages of activated and/or differentiated LCH cells. Remarkably, CLA-antigen expression on LCH-cells was not restricted to cutaneous sites. In view of recent findings on the expression of HECA-452 on resting epidermal LC, our data are compatible with the view that local cytokine production by keratinocytes or cells from the surrounding infiltrate induce and/or modulate CLA expression on LC in both cutaneous and extra-cutaneous sites.This work is dedicated to Professor Dr. Thaddäus Radaszkiewicz, who died in September 1995 相似文献
96.
Finegold I 《Clinical reviews in allergy & immunology》2004,27(2):75-82
Recent results of allergen immunotherapy research have continued to validate efficacy and have also demonstrated a truly preventive
aspect for this treatment. This review summarizes the basic principles of effective allergen immunotherapy and highlights
some of the advances that have been published in the past year. These studies show that allergen immunotherapy, when done
appropriately and properly, not only causes a decrease in symptoms and use of medication as well as an improved quality of
life, but that the progression of disease from allergic rhinitis to asthma is substantially decreased and the development
of new allergies is diminished. In addition, laboratory studies continue to demonstrate significant changes in the immune
system with a shift in the immune pathway from TH2 toward a TH1 response. The impact of anti-IgE as a therapeutic agent with allergen immunotherapy is also be reviewed. 相似文献
97.
以5%乙酸冲洗正常人膀胱,获得膀胱粘膜酸溶性提取物。电泳凝胶琼脂糖弥散法抗菌实验分析表明,膀胱粘膜酸溶性提取物中有一条主蛋白带(称之为HBP)对致病性大肠杆菌ML-35P株有抗菌活性。以超滤方法对膀胱粘膜酸溶性提取物进行分离纯化,获得分子量低于1×10~4的超滤纯化样品,其中主要含HBP。琼脂糖弥散法抗菌实验结果表明,超滤纯化样品对大肠杆菌ML-35P株、绿脓杆菌ATCC27853株、金黄色葡萄球菌ATCC25923株及血链球菌S_34Sr株均有很强的抗菌活性。采用Tricine-SDS-pAGE鉴定,超滤纯化样品主要显示为两条分子量分别为6.7×10~3和8.5×10~3的多肽。研究结果首次提示,人膀胱粘膜内存在抗菌活性很强的内源性抗生肽,是膀胱抗感染防御的主要因素。 相似文献
98.
目的 分析拓扑异构酶的突变和外排泵系统在大肠埃希菌(Escherichia coli)氟喹诺酮类药物耐药机制中的作用.方法 本研究通过基因重组技术对大肠埃希菌中拓扑异构酶不同点突变的功能进行了准确测定,同时也对大肠埃希菌中不同外排泵及膜蛋白的功能进行了分析.结果 在不同的菌株中,acrAB或tolC的切除所引起细菌耐药性的变化不同.对拓扑异构酶点突变的功能分析显示,gyrA中的点突变(S83和D87)在喹诺酮耐药机制中起主要作用,没有gyrA上的点突变,parC上的点突变(S80和A108)对细菌的耐药性不产生影响,但单独gyrA上的点突变(S83和D87)也仅导致敏感菌株对萘啶酸耐药,而对其他氟喹诺酮类药物仍表现为敏感.当对喹诺酮敏感的大肠埃希菌K-12同时具备gyrA(S83L和D87N)和parC(S801和A108V)上的点突变后,重组菌株对氟喹诺酮会自然产生耐药性,而并不需要过度表达的外排泵.结论 拓扑异构酶的突变在大肠埃希菌氟喹诺酮药物的耐药机制中起主要作用,对氟喹诺酮药物耐药的菌株通常应同时具备gyrA和parC上的点突变. 相似文献
99.
目的 检测LPS刺激后小鼠腹腔巨噬细胞HMGB1和相关信号分子p38MAPK、NF-κB、CBP的表达,探讨脓毒症时巨噬细胞表达和释放HMGB1的信号传导机制。 方法 采用LPS刺激RAW264.7细胞,在不同的时间点用免疫细胞化学、激光共聚焦显微镜观察细胞内相关信号分子p38MAPK、NF-κB、CBP的变化,ELISA检测培养上清HMGB1的含量,Real-time PCR检测培养细胞HMGB1的mRNA水平,Western blot检测胞浆和胞核内HMGB1的含量。 结果 随着LPS的刺激,细胞浆内p38MAPK的绿色荧光逐渐增强,NF-κB的绿色荧逐渐减弱,而细胞核内NF-κB绿色荧光逐渐增强,CBP的绿色荧光逐渐增强,三者均于刺激后6 h达高峰。LPS刺激后12-48 h培养细胞胞浆和上清中HMGB1蛋白含量逐渐增加,而12-24 h胞核内HMGB1含量逐渐减少,36 h后又逐渐增多,各不同时间点差异具有显著性(P<0.01);而细胞内HMGB1 mRNA表达在LPS刺激后0-12 h无明显变化, 24 h、36 h和48 h明显增高,与0h相比差异有显著性(P<0.01)。 结论 LPS通过依次激活巨噬细胞内信号分子p38MAPK、NF-κB及CBP来诱导HMGB1的合成、转位和释放表达的。 相似文献
100.
Perl ER 《Progress in neurobiology》2011,94(1):20-38
This commentary on ideas about neural mechanisms underlying pain is aimed at providing perspective for a reader who does not work in the field of mammalian somatic sensation. It is not a comprehensive review of the literature. The organization is historical to chronicle the evolution of ideas. The aim is to call attention to source of concepts and how various ideas have fared over time. One difficulty in relating concepts about pain is that the term is used to refer to human and animal reactions ranging from protective spinal reflexes to complex affective behaviors. As a result, the spectrum of "pain"-related neural organization extends to operation of multiple neuronal arrangements. Thinking about pain has shadowed progress in understanding biological mechanisms, in particular the manner of function of nervous systems. This essay concentrates on the evolution of information and concepts from the early 19th century to the present. Topics include the assumptions underlying currently active theories about pain mechanisms. At the end, brief consideration is given to present-day issues, e.g., chronic pain, central pain, and the view of pain as an emotion rather than a sensation. The conceptual progression shows that current controversies have old roots and that failed percepts often resurface after seemingly having been put to rest by argument and evidence. 相似文献