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31.
Test of genetic heterogeneity of cleft lip with or without cleft palate as related to race and severity 总被引:6,自引:0,他引:6
The question of possible heterogeneity among population groups and phenotypic groups on the role of major gene in the etiology of cleft lip with or without cleft palate [CL(P)] was examined using the uniformly collected data in Hawaii. Complex segregation analysis was used to analyze patterns of family resemblance under the mixed model incorporating the effects of major gene and multifactorial inheritance. Analysis of the entire data showed superior fit of the mixed model including the effects of both major gene and multifactorial inheritance over the model of major gene alone or multifactorial inheritance alone. No significant heterogeneity could be detected between the high-incidence group (Oriental or Japanese) and the low-incidence group (non-Oriental) in the underlying general model, although higher heritability was observed in general. When families were classified into "severe" and "mild" phenotypes based on cleft lip vs. cleft lip and palate or unilateral vs. bilateral cleft in the proband, no significant differences could be detected between the two types in the underlying genetic model. 相似文献
32.
Since Berger's original paper on mesangial IgA-IgG deposition with hematuria, there have been a number of clinical and pathological studies regarding IgA immune complexes, the mechanisms of glomerular IgA deposition leading to glomerular injury and animal models of IgA nephropathy. During the last quarter of this century, glomerular changes such as IgA nephropathy have also been observed in cases associated with other diseases, such as systemic lupus erythematosus, Schoenlein-Henoch purpura, liver cirrhosis and chronic inflammatory diseases of the lung. This evidence supports the idea of an IgA nephropathy syndrome. On the other hand, IgA is thought to be an important humoral factor at the mucosal immune system and appears to have an antibody function against various etiologic candidates of extrinsic or intrinsic substances at the mucosal and systemic immune system. Glomerular IgA deposition in IgA nephropathy syndrome is thought to result from elevated levels of circulating immune complexes or aggregated IgA due to an overproduction of polymeric IgA as antibodies in the serum and due to the clearance impairment of IgA immune complexes in the hepatic and splenic phagocytic system. The glomerular IgA subclass is not one-sided, but should be evaluated in comparison with the age of patients at renal biopsy; this indicates the approximate age of onset. Cirrhotic IgA glomerulonephritis is not related to Hepatitis B or C virus infection, but to the pathophysiologic condition of liver cirrhosis. Various etiologic candidates such as viral, microbial, dietary antigens or auto-antigens have been listed and experimental models of IgA nephropathy syndrome have provided some clues in understanding the etiology of primary IgA nephropathy. However much still remains to be clarified and some specific epitopes common among these etiologic candidates will have to be identified. 相似文献
33.
34.
Selmi C Ichiki Y Invernizzi P Podda M Gershwin ME 《Clinical reviews in allergy & immunology》2005,28(2):73-81
Primary biliary cirrhosis (PBC) is a chronic cholestatic disease characterized by a striking predominance in female patients
(with most cases diagnosed between ages 40 and 60 yr) as well as serum auto-antibodies to mitochondrial antigens, elevated
serum immunoglobulin M, progressive destruction of intrahepatic bile ducts, and, ultimately, liver cirrhosis and failure (1). The precise mechanisms leading to selective destruction of biliary epithelial cells lining intrahepatic bile ducts are
still unknown, although numerous immunomediated pathways have been proposed. Genetic background appears to be important in
determining susceptibility to the disease (2), but no clear association with alleles in the major histocompatibility complex has been identified. Molecular mimicry either
by infections (3) or xenobiotics (4) has been proposed to be capable of breaking tolerance in genetically predisposed individuals, thus leading to onset of PBC.
This article describes and discusses the available data regarding the immunomediated pathogenesis of PBC (with particular
attention to auto-antibodies and autoreactive T-cells) and presents the recent evidence indicating a role for either xenobiotic
chemicals or novel infectious agents in the induction of the disease. 相似文献
35.
L Begg L H Kuller J P Gutai A G Caggiula N Wolmark C G Watson 《Genetic epidemiology》1987,4(4):233-247
Sex-steroid hormones are a major determinant of the risk of breast cancer. We evaluated the relationship between obesity and endogenous estrogen levels in 79 healthy, postmenopausal women. Thirty-nine of the women were siblings of patients with postmenopausal-onset breast cancer; the remaining women were age-matched (+/- 10 yr) controls. Our hypothesis was that the siblings of the breast cancer patients would weigh more and that this excess weight would lead to higher serum estrone levels. The choice of unaffected family members of breast cancer patients reduces the concern that results may have been influenced by the cancer rather than antecedent to its development. Our findings demonstrated a statistically significant excess estrone level in the siblings compared to the controls (58.9 vs 47.8 pg/ml, P = 0.005). The siblings weighed 4.3 kg more than the controls. Matched pairs analysis (sibling-control), adjusting for weight, also showed significant differences in serum estrone levels. These differences were observed despite comparability in dietary intake, medication use, and personal medical history. These findings represent the first time that higher estrogen levels have been measured in siblings of postmenopausal breast cancer patients. This observation may represent an important link in our understanding of the relationship between genetic and environmental risk factors of breast cancer. One approach to subsequent genetic studies of breast cancer may be to focus on the possible biological determinants such as sex-steroid hormone level receptors, oncogenes, and gene products and not on the "familial aggregation" of breast cancer. 相似文献
36.
拒绝上学(SR)是儿童常见的心理行为问题之一,主要表现为儿童不愿上学或对学习、学校不感兴趣,甚至完全拒绝去学校。目前越来越多研究表明大多数拒绝上学儿童伴有焦虑、抑郁等情绪问题,对其学业、家庭、人际关系等各方面产生广泛且负面的影响。本文主要综述儿童拒绝上学的定义、评估方法、病因、治疗及预后,有助于临床医生进一步探究拒绝上学儿童的病因并及时地进行评估与干预,帮助其改善临床结局,尽早重返校园。 相似文献
37.
早期新生儿死亡属于围产儿死亡的一部分,其定义为新生儿出生后0~6天死亡。通常认为男性新生儿、先天异常、早产、低出生体重和5分钟Apgar评分低于7分等是早期新生儿死亡最常见的相关因素。但是仍有相当多的早期新生儿死亡病因不明,其为产科及儿科医务人员比较棘手的问题,也容易引发医患矛盾。近年来发现,除上述常见的病因外,基因缺陷和代谢性疾病在早期新生儿死亡中亦占有相当的比例,而通过全基因测序和串联质谱检测技术,可能对寻找部分既往被归于不明原因早期新生儿死亡病例的病因有一定的帮助。该文就早期新生儿死亡病因及可能机制、病因评估方法等进行综述。 相似文献
38.
Philip Eisermann Dennis Rubbenstroth Daniel Cadar Corinna Thom-Bolduan Petra Eggert Alexander Schlaphof Frank Leypoldt Martin Stangel Thorsten Fortwngler Florian Hoffmann Andreas Osterman Sabine Zange Hans-Helmut Niller Klemens Angstwurm Kirsten Prtner Christina Frank Hendrik Wilking Martin Beer Jonas Schmidt-Chanasit Dennis Tappe 《Emerging infectious diseases》2021,27(5):1371
Human bornavirus encephalitis is a severe and often fatal infection caused by variegated squirrel bornavirus 1 (VSBV-1) and Borna disease virus 1 (BoDV-1). We conducted a prospective study of bornavirus etiology of encephalitis cases in Germany during 2018–2020 by using a serologic testing scheme applied along proposed graded case definitions for VSBV-1, BoDV-1, and unspecified bornavirus encephalitis. Of 103 encephalitis cases of unknown etiology, 4 bornavirus infections were detected serologically. One chronic case was caused by VSBV-1 after occupational-related contact of a person with exotic squirrels, and 3 acute cases were caused by BoDV-1 in virus-endemic areas. All 4 case-patients died. Bornavirus etiology could be confirmed by molecular methods. Serologic testing for these cases was virus specific, discriminatory, and a practical diagnostic option for living patients if no brain tissue samples are available. This testing should be guided by clinical and epidemiologic suspicions, such as residence in virus-endemic areas and animal exposure. 相似文献
39.
94例缺铁性贫血患者的病因分析 总被引:3,自引:0,他引:3
目的 :通过对确诊为缺铁性贫血的病例进行病因学分析 ,探讨多病变和恶性肿瘤在缺铁性贫血发病中的重要性。方法 :确诊为缺铁性贫血 (IDA)的患者 94例 ,行大便虫卵检查 ,胃镜、结肠镜或钡餐、钡灌肠 ,腹腔B超 ,女性加做妇科检查及盆腔B超检查 ,找出IDA病因。将 94例患者按病因分类分为单一病因组和多病变组 ,用t检验对两组的Hb、SF值进行比较 ;再分为良性病变组和恶性肿瘤组 ,两组间的Hb、SF值也以t检验进行比较。结果 :94例IDA患者的病因中 ,由单一病因致病者 75 .5 % ,以消化性溃疡 (2 7.7% )和慢性胃炎 (17.0 % )为主 ,月经失血过多(2 0 .2 % )仍是女性患者的主要病因 ;多病变致病者 2 4.5 %。良性病变占 86 .2 % ,消化道恶性肿瘤占 13.8%。各组间Hb值均无显著差别 (P >0 .0 5 ) ,但恶性肿瘤组SF值明显高于良性病变组 (P <0 .0 1)。结论 :良性消化道出血性病变仍是导致IDA的主要原因 ,其次为女性月经过多。但多病变导致缺铁 ,尤其是上下消化道多个失血灶同时存在者 (14.9% )也不少见。恶性肿瘤在IDA病因中有增多趋势。恶性肿瘤致IDA的患者SF较高。 相似文献
40.
目的 分析小儿再发性腹痛的病因以及相关的因素为临床选择辅助检查及诊断提供依据或参考。方法 268例再发性腹痛患儿选人调查对象,对其进行病因学调查,调查内容包括年龄、性别、季节、诱因、部位等8个因素,进行分析。选择相关的辅助检查确定病因。结果 有52例有器质性疾病(19.4%),以慢性胃炎居首位。与发作有关的因素有季节、年龄、情绪反应。结论 小儿再发性腹痛绝大多数属于功能性疾病,只有少数由器质性原因引起,但仍应引起足够重视,谨慎的选择辅助检查,避免漏诊。 相似文献