全文获取类型
收费全文 | 61999篇 |
免费 | 3617篇 |
国内免费 | 1003篇 |
专业分类
耳鼻咽喉 | 486篇 |
儿科学 | 1102篇 |
妇产科学 | 787篇 |
基础医学 | 3602篇 |
口腔科学 | 961篇 |
临床医学 | 7095篇 |
内科学 | 6035篇 |
皮肤病学 | 822篇 |
神经病学 | 2954篇 |
特种医学 | 1814篇 |
外科学 | 4501篇 |
综合类 | 13457篇 |
一般理论 | 2篇 |
预防医学 | 5235篇 |
眼科学 | 388篇 |
药学 | 9314篇 |
162篇 | |
中国医学 | 5048篇 |
肿瘤学 | 2854篇 |
出版年
2024年 | 159篇 |
2023年 | 899篇 |
2022年 | 1935篇 |
2021年 | 2516篇 |
2020年 | 2453篇 |
2019年 | 2241篇 |
2018年 | 1991篇 |
2017年 | 2187篇 |
2016年 | 2501篇 |
2015年 | 2486篇 |
2014年 | 6479篇 |
2013年 | 5632篇 |
2012年 | 5398篇 |
2011年 | 5123篇 |
2010年 | 3842篇 |
2009年 | 2753篇 |
2008年 | 2535篇 |
2007年 | 2357篇 |
2006年 | 1924篇 |
2005年 | 1438篇 |
2004年 | 1136篇 |
2003年 | 967篇 |
2002年 | 780篇 |
2001年 | 699篇 |
2000年 | 643篇 |
1999年 | 475篇 |
1998年 | 358篇 |
1997年 | 294篇 |
1996年 | 237篇 |
1995年 | 224篇 |
1994年 | 199篇 |
1993年 | 147篇 |
1992年 | 112篇 |
1991年 | 107篇 |
1990年 | 87篇 |
1989年 | 97篇 |
1987年 | 85篇 |
1986年 | 82篇 |
1985年 | 387篇 |
1984年 | 454篇 |
1983年 | 285篇 |
1982年 | 386篇 |
1981年 | 279篇 |
1980年 | 236篇 |
1979年 | 231篇 |
1978年 | 171篇 |
1977年 | 118篇 |
1976年 | 118篇 |
1975年 | 120篇 |
1974年 | 82篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
目的 探讨绝经后阴道出血的病因。方法 分析242例绝经后阴道出血并行诊断性乔宫的临床和病理资料。结果 绝经后阴道出血的主要病理诊断分另是功能性子宫内膜(60.73%)、炎症(28.92%)和恶性肿瘤(10.35%)。结论 内分泌紊乱性疾病是绝经后出血的常见病因,年老妇女恶性肿瘤发生率高。 相似文献
62.
误诊为肉瘤的结节性筋膜炎之临床病理研究 总被引:2,自引:0,他引:2
目的:探讨结节性筋膜炎被误诊为肉瘤的原因,方法观察74例被误诊为肉瘤的结节性筋膜炎临床病理及免疫组化特点,其中对62例采用ABC、LSAB法行免疫组化染色。结果74例病人临床表现均为良性经过,但镜下组织学极似肉瘤形态,68例获随访,结果均存活,复发率不足1%,62例做了免疫组织化学染色,梭形细胞Vimentin阳性,MSA,SMA和KP1部分病例阳性,Keratin、S-100、Desimin均为 相似文献
63.
Prolonged clinico-immunological observation of 85 patients with definite multiple sclerosis (MS) was performed in order to elucidate the connections between the clinical and immune state. A battery of immunological investigations was performed, including estimation of T-cell subpopulations in blood and cerebrospinal fluid (CSF); proliferative responses of circulating lymphocytes to mitogens, recombinant interleukin-2 (rIL2) and myelin basic protein levels in different culture conditions; levels of immunoglobulin (Ig) in sera and CSF, and of Ig production in vitro; indices of IL2 synthesis and IL2 sensitivity; production of prostaglandin E2 and tumour necrosis factor (TNF) alpha by monocytes and levels of -endorphin in sera and supernatants phytohaemagglutinin of (PHA)-activated cells. Clinical observation was performed periodically using Kurtzke scales and was supplemented by repeated recording of evoked potentials and magnetic resonance imaging. Initial investigations showed specific differences between patients with MS and the control groups (donors and patients with other neurological disorders of the same age). Correlative and regressive analyses showed no association between immunological and clinical parameters at the initial investigation, although immunological indexes were inter-related, and indicated specific alterations in immuno-regulation in MS. Retrospective analysis revealed associations between the clinical status of patients with MS and their previous immune status. Evidence of cell activation — including a decreased percentage of circulating cells with differential antigens, lower cell mitogen-induced proliferative responses in vitro, with restoration following the addition of autoserum, greater IL2 sensitivity, and increased TNF-alpha production by macrophages — often predicted the clinical manifestation of deterioration. It is proposed that the immunopathological process in MS has a number of stages with characteristic features, and that progression from one stage to another can be subclinical. No single immunological index can be used to determine stage. Only systemic alterations reflect the real situation, whilst every patient has some abnormalities. A system of clinico-immunological monitoring could severe as the basis for a new approach to the dynamic treatment of MS. 相似文献
64.
目的 :ABO亚型在临床输血中经常造成错定血型及输血反应 ,因而研制抗A1试剂血清是解决ABO亚型鉴定的主要途径。方法 :采用血型血清学特异性抗原抗体吸收实验。结果 :经大量反复实验 ,研制出特异性强 ,效价符合要求的抗A1试剂血清。结论 :抗A1血清是鉴定A亚型的专用试剂血清 ,对临床鉴定ABO亚型及安全输血有实用意义。 相似文献
65.
Prevalence and clinical relevance of Blastocystis hominis in diverse patient cohorts 总被引:3,自引:0,他引:3
Oscar Cirioni Andrea Giacometti Davide Drenaggi Fausto Ancarani Giorgio Scalise 《European journal of epidemiology》1999,15(4):387-391
The pathogenicity of Blastocystis hominis is extensively debated in the medical literature. Therefore, we did a prevalence study to investigate the association between the presence of several intestinal parasites and gastrointestinal symptoms in diverse patient cohorts. The study population consisted of 1216 adults, including immunocompromised patients, institutionalized psychiatric or elder subjects, immigrants from developing countries, travellers to developing tropical countries and controls. Several variables for each risk group were considered. Stools specimens, collected in triplicate, were processed by the same technicians. Clinical data about each subject were provided by standardized questionnaires. The presence of gastrointestinal symptoms were related to the presence of any parasite. In addition, on the basis of microbiological results, five subgroups of subjects were evaluated. The results showed a high prevalence of parasites in all the risk groups. Immunocompromised status, recent arrival from developing countries and the presence of behavioural aberrations were significantly related to presence of parasites. B. hominis was the parasite most frequently detected in each studied group. B. hominis showed a significant correlation with gastrointestinal symptoms only when detected in the group including subjects with a severe immunodepression. Immunodepression seems to be a factor of primary importance of the pathogenic role of B. hominis. 相似文献
66.
From a Pediatric Rheumatology Clinic 361 children diagnosed as juvenile rheumatoid arthritis (JRA) according to American Rheumatism
Association-JRA criteria were studied retrospectively for their clinico-immunological profile. The mean age of onset in systemic,
pauciarticular and polyarticular onset, JRA subtypes were 5.2, 6.8 and 7.2 years respectively. There was male preponderance
in systemic and pauciarticular JRA. In seropositive polyarticular JRA, girls outnumbered boys. The frequency of occurence
of systemic, pauciarticular and polyarticular disease was 87 (24%), 108 (30%) and 166 (46%) respectively. The systemic onset
disease was dominated by extra-articular manifestations in terms of fever (100%), rash (57%), hepatomegaly (51%) and lymphadenopathy
(25%). The pauci- and polyarticular illnesses were commonly dominated by joint involvement, morning stiffness, and in few
patients, by extra-articular manifestations also. The joints were involved symmetrically. Most commonly involved joints in
order of decreasing frequency were knee, ankle, wrist and elbow in all the subtypes. Anemia and leucocytosis were observed
in majority with higher frequency in systemic onset JRA. The rheumatoid factor (RF) was present in 15% of polyarticular JRA.
RF was also present in 7 and 9% of patients with pauciarticular and systemic subtypes respectively. The antinuclear antibody
was positive in only 3 out of 66 patients in whom the test was carried out.
The demographic profile and trends in clinical features were similar to the studies reported on caucasian population with
difference in the actual frequency of various clinical features. 相似文献
67.
Jan Lycke Bo Svennerholm Elisabeth Hjelmquist Lars Frisén Gaby Badr Mats Andersson Anders Vahlne Oluf Andersen 《Journal of neurology》1996,243(3):214-224
Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on intent-to-treat data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation. 相似文献
68.
P. W. Hanlo R. H. J. M. Gooskens J. A. J. Faber R. J. A. Peters A. A. M. Nijhuis W. P. Vandertop C. A. F. Tulleken J. Willemse 《Child's nervous system》1996,12(4):200-209
The treatment of choice in progressive hydrocephalus is drainage of cerebrospinal fluid in order to reduce elevated intracranial pressure (ICP). Defining the right moment for surgical intervention, however, in a hydrocephalic infant on the basis of clinical signs alone can be a difficult task. Clinical signs of raised ICP are known to be unreliable and sometimes even misleading. In the present study, the relationship between long-term anterior fontanelle pressure (AFP) measurements and clinical signs was investigated in 37 infants with hydrocephalus. The decision as to whether to operate or not was based on clinical signs alone; AFP values were not taken into account. There was an overall difference between the non-operated group and the preoperative measurements in the operated group, and also between the preoperative and the postoperative measurements in the latter, in regard to both AFP measurements and clinical signs. Almost all preoperative AFP values were increased. The direct correlation () between most individual clinical signs and AFP levels, however, was low (=0.15–0.41). The clinical sign tense fontanelle showed the best correlation with the AFP levels (=0.75). Furthermore, using logistic regression analysis, no combination of clinical signs could be found which reliably predicted the AFP. The relationship between the AFP pressure variables and clinical signs was also examined. The pathological A-waves occurred only in the presence of raised (baseline) AFP, a situation in which considerably more frequent B-waves were observed as well. It was concluded that clinical signs of raised ICP in infantile hydrocephalus are not very reliable and AFP monitoring can therefore provide valuable information on intracranial dynamics in patients with dubious neurological manifestations of progressive hydrocephalus. 相似文献
69.
G. Dhom 《Journal of cancer research and clinical oncology》1983,106(3):210-218
Summary The worldwide incidence of prostate cancer differs greatly. The black population of the USA is at the head, while the Asian populations have the lowest incidence and mortality rates. Comparative geographic-pathologic autopsy studies on frequency and growth type of latent prostate carcinomas show that in populations with a lower incidence, for example Japan and Singapore, latent carcinomatous foci are not considerably rarer than in regions with high incidence. However, obvious differences are seen when comparing the size of the foci and the growth types. In countries with low incidence and mortality rate, the foci of the latent prostate carcinoma are small and show a slight proliferating tendency, whereas in countries with high incidence and mortality rate, they are frequently larger and more aggressive. Consequently, the different incidence of prostate cancer is not based on different initiation of malignant transformation, but on different promoting factors. In histologic-bioptical specimens from regions with high incidence and mortality rate, pluriform tumor types of malignancy grade G III and G II prevail. Definite causes of prostate cancer could not be detected by case control and migration studies up to now.Supported by the campaign Kampf dem Krebs e.V. der Deutschen Krebsgesellschaft 相似文献
70.
Focal segmental membranous glomerulonephropathy associated with other glomerular diseases 总被引:2,自引:0,他引:2
T Bertani G B Appel V D'Agati M A Nash C L Pirani 《American journal of kidney diseases》1983,2(4):439-448
In four patients with the nephrotic syndrome, renal biopsy revealed focal segmental membranous glomerulonephropathy (FSMGN) associated with the histologic patterns of "nil" disease (two cases), hereditary nephritis and diffuse diabetic glomerulosclerosis. The occurrence of FSMGN in association with other glomerular diseases, presumably unrelated to immune complex deposition, is infrequent in our experience. Rather than necessarily representing an early stage or milder form of membranous glomerulonephropathy, it may be an epiphenomenon. This interpretation has prognostic and therapeutic implications and raises important pathogenetic questions. In particular, this study suggests that in some instances, preexisting functional and structural abnormalities may play a role either in the deposition of preformed circulating immune complexes or in the local formation of immune complexes. 相似文献