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21.
22.
Selective cytokine production by epithelial cells following exposure to Escherichia coli. 总被引:8,自引:18,他引:8 下载免费PDF全文
W Agace S Hedges U Andersson J Andersson M Ceska C Svanborg 《Infection and immunity》1993,61(2):602-609
This study compared the repertoire of cytokines produced by epithelial cell lines and human peripheral blood monocytes in response to Escherichia coli. The A-498 and J82 urinary tract epithelial cell lines and human peripheral blood monocytes were exposed to E. coli Hu734. The cytokine content of single cells was detected by indirect immunofluorescence using monoclonal antibodies to interleukin-1 alpha (IL-1 alpha), IL-1 beta, tumor necrosis factor alpha (TNF-alpha), TNF-beta, IL-6, IL-8, and granulocyte macrophage-colony-stimulating factor, and the number of positive cells was used to quantitate the response. The J82 bladder cell line stained positive for IL-6, IL-8, and IL-1 alpha. The IL-8 and IL-6 response peaked at 2 h, while the number of IL-1 alpha-positive cells reached a peak 6 h after E. coli stimulation. The A-498 kidney cell line stained for IL-8 with a peak at 2 h and IL-6 with a peak at 6 h after E. coli stimulation. Peripheral blood monocytes stained for the cytokines IL-1 alpha, IL-1 beta, IL-8, IL-6, and TNF-alpha but not for TNF-beta and granulocyte macrophage-colony-stimulating factor after stimulation with E. coli. The results demonstrated that bacteria activated a cytokine response in the epithelial cell lines and monocytes. The epithelial cell lines had a more limited cytokine response profile than circulating monocytes, which may serve to limit the consequences of microbial exposure at the mucosal surface and help maintain the integrity of other tissue compartments. 相似文献
23.
Semaan S Des Jarlais DC Sogolow E Johnson WD Hedges LV Ramirez G Flores SA Norman L Sweat MD Needle R 《Journal of acquired immune deficiency syndromes (1999)》2002,30(Z1):S73-S93
We examined the effectiveness of 33 U.S.-based HIV intervention studies in reducing the sexual risk behaviors of drug users by reducing unprotected sex or increasing the use of male condoms. The studies, identified as of June 1998, through the HIV/AIDS Prevention Research Synthesis project, were published in 1988 or later, measured behavioral or biologic outcomes, used experimental designs or certain quasi-experimental designs, and reported sufficient data for calculating an effect size for sexual risk reduction. Of the 33 studies, 94% recruited injection drug users; 21% recruited crack users. The mean age of participants was 36 years. Almost all studies were randomized (94%), provided another HIV intervention to the comparison groups (91%), and evaluated behavioral interventions (91%). On average, interventions were conducted in 5 sessions (total, 10 hours) during 4.5 months. Interventions compared with no interventions were strong and significant (k = 3; odds ratio [OR], 0.60; 95% confidence interval [CI], 0.43-0.85). Interventions compared with other HIV interventions showed a modest additional benefit (k = 30; OR, 0.91; 95% CI, 0.81-1.03). When we extrapolated our result (an OR of 0.60) to a population with a 72% prevalence of risk behavior, the proportion of drug users who reduced their risk behaviors was 12.6% greater in the intervention groups than in the comparison groups. Our meta-analysis shows that interventions can lead to sexual risk reduction among drug users and justifies providing interventions to drug users. Developing interventions with stronger effects to further reduce sexual risk behaviors among drug users must remain a high priority. 相似文献
24.
Clinical features and mechanism of occipital infarction 总被引:6,自引:0,他引:6
M S Pessin E S Lathi M B Cohen E S Kwan T R Hedges L R Caplan 《Annals of neurology》1987,21(3):290-299
To clarify the clinical features and mechanism of infarction in the posterior cerebral artery territory, we investigated 35 consecutive patients who presented with homonymous visual field defects and occipital infarction documented by computed tomography. Cerebral angiographic findings in 23 patients, and the clinical features of rare transient ischemic attacks and maximal deficit occurring at stroke onset, were consistent with embolism of the posterior cerebral artery. Visual field defects were the only neurological abnormality in 17 patients; the remainder had additional findings. Three patients had a major brainstem stroke. Stroke in the posterior cerebral artery territory was found in a heterogeneous group of patients, although embolism was the most common stroke mechanism. Several distinct patient groups were identified: cardiac source embolism (10 patients), vertebrobasilar atheroma with local embolism (6), migraine (5), systemic illness with presumed coagulopathy (3), and "unknown source embolism" after negative cardiac investigation (11 patients). During follow-up, 26 patients had no further neurological events (the majority on anticoagulation or antiplatelet treatment), 3 suffered new strokes, and 6 died. 相似文献
25.
The evaluation of the patient with a "sore throat" is deceptively complex. The clinician must first assess the potential for airway compromise. Specific risk factors, reviewed in this article, should be considered, including the presence of a pharyngeal membrane, immunocompromise, potential gonococcal exposure, and prior rheumatic fever. 相似文献
26.
1 临床资料 患者 ,女 ,6 1岁 ,1999- 0 6 - 0 3日确诊为急性红白血病 (M6 ) .先后 4次住院 ,鉴定血型均为 O型 . 2 0 0 0 - 0 1- 2 2日复诊 ,正反鉴定表明 ,患者红细胞与抗 - B不凝集 ,与抗 - A凝集 ,血清中有抗 - B抗体 (表 1) ,吸收释放试验证实为 A型 (表2 ) .输 A型浓缩红细胞 2 μ,无不良反应 .表 1 血型正反鉴定试剂血清试剂红细胞标本抗 A 抗 B 抗 A+ B Ac Bc Oc被检红细胞 2 + -3+ ---自身血清 -3+ -表 2 吸收、放散试验被检 RBC吸收抗血清后上清被检 RBC吸收抗血清后释放液试剂细胞抗 A修正液抗 B修正液抗 A修正液抗… 相似文献
27.
综合疗法治愈狼疮性急性肾衰1例 总被引:3,自引:2,他引:1
1 病例报告 患者 ,女 ,6 0岁 ,因反复发热 2 5 a、全身性关节疼痛 2 3 a,双下肢水肿 2 mo,腹胀、尿少 1mo,于 1998- 10 - 2 0入院 .1975年患者出现发热 ,全身关节疼痛 ,四肢关节周围皮肤出现结节性红斑 ,触之疼痛 ,多次化验血沉 115 mm· h- 1 ,抗核抗体阴性 ,类风湿因子阳性 ,未找到狼疮细胞 ,诊断为“类风湿性关节炎”.1986年因上述症状复发再次入我院 ,多次检查后发现血抗核抗体 ( ) ,抗双链 DNA抗体 ( ) ,临床确诊为系统性红斑狼疮 (SL E) ,狼疮性肝炎 ,狼疮性胸膜炎 ,狼疮性肺炎 .经治疗好转 ,但上述症状反复发作 .此次上述症状复… 相似文献
28.
The serum electrolyte panel (SEP) is commonly ordered in the workup of the emergency department (ED) patient. This study was done: 1) to evaluate the efficacy of the SEP in terms of the identification of clinically significant abnormals (yield) and the impact on therapeutic plan (impact); 2) to evaluate the reasons that the test was ordered; and 3) to compare the expected and realized contributions of the test to patient care. Pretest and posttest questionnaires were administered to physicians managing 800 ED patients greater than or equal to 55 years old for whom SEPs were ordered. The yield of significant abnormals was 16%. Fluid and electrolyte treatment plans were modified after the SEP results became known in 35% of cases. This modification was associated with a normal SEP 48% of the time. Both the yield and the impact of the SEP were related to the reason that the test was ordered. The most common reason given was "to look for an unexpected abnormality" (50%). Physicians' expectations for the contribution of the SEP to patient care decisions were greater than the contributions realized after the results were known. However, in 115 cases, the test contributed more than expected. Physicians predicted that 13% of the tests would contribute nothing to patient care. After the results were known, they felt that 38% had made no contribution. Physicians tend to overestimate the potential impact of the SEP but are occasionally surprised by a result that contributes more than expected. Thus, there is considerable pretest uncertainty about treatment decisions and normal results appear to have a substantial impact. 相似文献
29.
WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
30.
Dermoid tumours in children usually occur in two locations: at the anterior fontanelle and on the occipital squama. An exceptional site of origin for a posterior fossa dermoid cyst is the extradural space. There are only six previous cases of this situation reported in the literature. A series of 103 subscalp and calvarial masses in children were reviewed and three children are reported with extradural dermoids of the posterior fossa, which communicated with the skin through midline occipital dermal sinuses. All three children were seen after the rapid growth or the formation of an abscess in a previously noted occipital subcutaneous mass present since birth. Although computed tomography or magnetic resonance imaging showed the dermal sinus and the intracranial tumour, these studies were unable to ascertain the intradural or extradural nature of the tumours, their exact origin only being established at operation. Histopathological study showed preclinical signs of infection in the two patients that had not yet formed an abscess. It is suggested that early neurosurgical treatment of these neoplasms should be done to prevent the development of severe intracranial infection. The previously reported simplicity of surgical removal of occipital extradural dermoids was not confirmed in this series. 相似文献