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101.
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103.
Intrauterine spermatic cord torsion in the newborn: sonographic and pathologic correlation 总被引:2,自引:0,他引:2
In five newborn patients with spermatic cord torsion, sonography demonstrated an enlarged and globular testis, hydrocele, and skin thickening. In four of these patients the testicular parenchyma was heterogeneous. Peripheral hypoechoic areas were seen in two of the four patients; the other two had a central hypoechoic region and a peripheral echogenic rim. The testis in the fifth patient was diffusely hyperechoic. Duplex Doppler sonography performed in two patients failed to demonstrate any signal in the spermatic cord in either the abnormal or contralateral hemiscrotum. Scintigraphic findings were positive for testicular torsion in two patients and equivocal in three patients. Surgery was performed 2-12 days after sonography and established the diagnosis of spermatic cord torsion. Pathologic examination demonstrated hemorrhagic infarction of the entire testis as well as scattered calcifications. The authors conclude that a solid globular testicular mass seen during the neonatal period is suggestive of intrauterine spermatic cord torsion. 相似文献
104.
INTRODUCTION: A rare case of a large jugular foramen tumour presenting as a posterior fossa mass is described. MATERIALS AND METHODS: The patient, a 13-year-old boy presented with symptoms of raised intracranial pressure and on MRI imaging demonstrated the tumour origin within the jugular foramen, with appearances suggestive of schwannoma. He underwent a complete excision as a single-stage procedure thorough a lateral suboccipital craniotomy with minimal morbidity. Histology confirmed the diagnosis of schwannoma (WHO I). Jugular foramen schwannoma is virtually unheard of in the paediatric population. CONCLUSION: The differential diagnosis of a jugular foramen tumour includes tumours of the glomus jugulare, meningiomas, schwannomas, myxomas and chondrosarcomas. The imaging characteristics are important when considering this differential diagnosis. 相似文献
105.
Mrs Terry Lumsden BS William R. Marshall BS George A. Divers BA SM Samuel D. Riccitelli BA MSEng 《Journal of clinical monitoring and computing》1994,10(1):59-66
Continuous intraarterial blood gas (IABG) monitoring is in clinical use both in the operating room and intensive care unit. This technology uses miniature, optically-based sensors that can be placed into a patient's artery. The arterial blood gas values are transduced into an optical signal that is measured by a bedside monitor on which the values are displayed. In this paper, we describe the operating principles of the PB3300 Intra-Arterial Blood Gas Monitoring System (Puritan-Bennett Corporation, FOxS Division, Carlsbad, CA). Topics include the principles of fluorescent determinations of pH,PCo
2, andPO
2; the optical path of the PB3300; system calibration; dye layer geometry; and clinical operation. The accuracy, precision, and drift of the system measuring tonometered aqueous standards are reported. The following values were noted for eight sensors sending data to eight monitors: system bias and precisions of 0.00±0.02 pH at a pH of 7.40, –2.5±1.5 mm HgPCo
2 at aPCo
2 of 40 mm Hg, and 3.3±1.3 mm HgPO
2 at aPO
2 of 80 mm Hg.
Abstrakt Die kontinuierliche intraarterielle Blutgasüberwachung (IABG) wird klinisch sowohl im OP als auch auf der Intensivstation eingesetzt. Hierbei werden miniaturisierte, optische Sensoren angewandt, die sich direkt in der Arterie des Patienten plazieren lassen. Die Blutgaswerte werden in optische Signale umgesetzt und von einem bettseitigen Monitor gemessen und angezeigt. In dieser Arbeit beschreiben wir das Funktionsprinzip des Intra-Arteriellen Blutgasanalysesystems PB3300 (Puritan-Bennett Corporation, FOxS Division, Carlsbad, CA). Themen sind die Grundlagen der Bestimmung von pH, PCO2 und PO2 mittels Fluoreszenz; die optische Übertragung des PB3300; die Kalibrierung des Systems; die Geometrie der Farbschichten und der Einsatz in der Klinik. Die Genauigkeit, Auflösung und Drift des Systems bei der Messung von tonometrischen wässrigen Standards wird beschrieben. Die folgenden Werte ergaben sich aus einer Meßreihe mit 8 Sensoren, die an 8 Monitore angeschlossen waren (jeweils Bias, Streuung und Sollwert): 0.00±0.02 pH bei 7.40 pH, –2.5±1.5 mmHg PCO2 bei 40 mmHg PCO2 und 3.3±1.3 mmHg PO2 bei 80 mmHg PO2.
Resumen La monitorizaciòn continua de gases intraarteriales tiene uso clinico, tanto en el pabellòn de operaciones como en la unidad de cuidados intensivos. Esta tecnologia utiliza sensores miniatura de tipo òptico que pueden ser introducidos en una arteria del paciente. Los valores de gases arteriales son transducidos en forma de señal òptica que es medida al lado de la cama del paciente por un monitor que presenta los valores numéricos. En este trabajo, describimos los principios de operaciòn del PB3300 Intra-Arterial Blood Gas Monitoring System (Puritan-Bennett Corporation, FOxS Division, Carlsbad, CA). Los temas incluyen los principios de determinaciones fluorescentes de pH, PCO2, and PO2; la via òptica del PB3300; calibraciòn del sistema; geometria de la capa de colorante; y la operaciòn clinica. Se presentan la exactitud, precisiòn, y deriva (drift) del sistema, midiendo soluciones acuosas de tonometrìa estàndar. Los siguientes valores fueron registrados para ocho sensores enviando informaciòn a ocho monitores: los sesgos del sistema y las precisiones fueron de 0.00±0.02 pH a pH 7.40, –2.5±1.5 mmHg PCO2 a PCO2 40 mmHg, y 3.3±1.3 mmHg PO2 a PO2 80 mmHg.相似文献
106.
Pre-B cells and other possible precursor lymphoid cell lines derived from patients with X-linked agammaglobulinemia 总被引:14,自引:6,他引:14 下载免费PDF全文
SM Fu JN Hurley JM McCune HG Kunkel RA Good 《The Journal of experimental medicine》1980,152(6):1519-1526
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out. 相似文献
107.
BACKGROUND: Cellular blood components are irradiated to prevent graft- versus-host disease in transfusion recipients at risk for this syndrome. Because gamma radiation can result in the production of reactive oxygen species, the role of reactive oxygen species was investigated in radiation-induced red cell damage. STUDY DESIGN AND METHODS: Whole blood from normal donors was exposed to various doses of t-butyl hydroperoxide (0-1 mM) and/or to gamma-radiation (0-50 Gy). Oxidative damage was assessed by the extent of lipid peroxidation (measured by thiobarbituric acid-reactive substances [TBARS]) and hemoglobin oxidation. Fresh blood was divided into three parts-one initially irradiated and stored, another stored with portions irradiated weekly, and a third stored without irradiation. TBARS and hemoglobin oxidation were measured weekly. RESULTS: As expected, t- butyl hydroperoxide induced TBARS formation and hemoglobin oxidation in a dose-dependent fashion. The gamma-radiation not only increased hemoglobin oxidation and TBARS formation, but also enhanced the t-butyl hydroperoxide effect on red cells. Red cell storage increased TBARS generation and hemoglobin oxidation in a time-dependent fashion. When radiation was administered either initially or after weekly storage, TBARS production and hemoglobin oxidation were increased over that measured in unirradiated paired controls. CONCLUSION: Gamma radiation at clinically used doses increases lipid peroxidation and hemoglobin oxidation in human red cells. The effect of gamma-radiation is accentuated by blood storage and induces damage independent of time of storage. 相似文献
108.
109.
上海市0~6岁小儿佝偻病的现状调查 总被引:14,自引:0,他引:14
目的:了解上海市小儿佝偻病的现状及影响因素。方法:2005年春季以整群和分层随机抽样法抽取上海市部分城区0~6岁小儿821名,采取问卷调查方法了解小儿的生活环境、饮食习惯、户外活动、营养状况、既往疾病史及母亲的妊娠情况等。佝偻病的诊断以1996年国家卫生部颁布的"婴幼儿佝偻病防治方案"为诊断标准。结果:取得完整有效资料769名,其中男童396名,女童373名;集居儿童456名,散居儿童313名。①小儿佝偻病患病率为17.3%(133/769),其中男童患病率为17.4%、女童为17.2%。②佝偻病与喂养方式(母乳喂养的患病率为13.0%、混合喂养的患病率为17.5%、人工喂养的患病率为25.2%)、鱼肝油添加(按时添加维生素D的患病率为13.5%、偶加或未加维生素D的患病率为32.5%)、居住环境(居住在市区的患病率为23.6%、居住在郊区的患病率为10.6%;集居儿童患病率为13.8%、散居儿童患病率为22.4%)、户外活动时间(经常户外活动的患病率为12.9%、偶尔户外活动的患病率为31.8%)、反复呼吸道感染(小儿有反复呼吸道感染的患病率为26.9%、无反复呼吸道感染的患病率为12.9%)、母孕期缺钙(母孕期有缺钙的患病率为33.2%、无缺钙的患病率为12.0%)等因素有关(P<0.01)。结论:上海市小儿佝偻病患病率有上升趋势。影响因素与城市环境污染、母乳喂养减少、年轻父母科学育儿知识缺乏等有关。 相似文献
110.
SM Tariq MRCP 《International journal of clinical practice》1996,50(2):99-102
SUMMARY Atopy development cannot yet be predicted with certainty, and primary prophylaxis has to be directed at every ‘at-risk’ infant. However, substantial progress has been made in identifying environmental factors associated with allergic disorders. The process of sensitisation to common allergens may begin in utero. The influence of adjuvants, especially passive smoking, is considerable in individuals with established atopic disease. This article examines the role of intervention during pregnancy and the first year of life in the primary prevention of atopy and suggests a number of measures based on the current evidence. 相似文献