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排序方式: 共有994条查询结果,搜索用时 15 毫秒
51.
Claude Altman MD Monique Fabre MD Christophe Adrien MD Christophe Frouge MD PhD Jacques Fritsch MD Etienne Martin MD Michel Bléry MD Jean-Pierre Etienne MD 《Digestive diseases and sciences》1995,40(10):2128-2133
The cholangiographic features of intrahepatic bile ducts associated with cirrhosis or fibrosis are not well known. In order to achieve a radiological—pathological correlation, we studied nine livers with fibrosis or cirrhosis excised at autopsy. Cholangiograms were obtained within 24 hr after death from the nonfixed liver and multiple tissues samples were taken for histologic examination. Radiological data were interpreted by two independent investigators blinded to the clinical and histological findings. Cirrhosis (alcoholic in 4, posthepatitis in two) was observed in six livers, fibrosis (alcoholic in 2, posthepatitis in one) in three. No liver with fibrosis had cholangiographic abnormalities. In contrast, cholangiography of all livers with cirrhosis was abnormal. Abnormalities were a diminished arborization, a decrease of the distal opacification, an irregularity of caliber, and a tortuous course of the bile ducts. Histological study showed that the irregular and tortuous course were due to compression of the bile ducts by regenerative nodules. Furthermore, a thick fibrosis was organized around the bile ducts. In conclusion, fibrosis alone was not associated with cholangiographic abnormalities. In cirrhotic livers, intrahepatic bile ducts showed an irregular and tortuous course, a diminished arborization and a decrease of the distal opacification. These abnormalities were secondary to the presence of regenerative nodules and fibrosis organized around the bile ducts. 相似文献
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Intracerebral injections of 6-hydroxydopamine directly in the nucleus locus coeruleus were performed in 4-day-old rats. The effects of such treatment on the subsequent development of this nucleus were analyzed and compared to those obtained in vehicle-injected age-paired controls. The 3 histological techniques used (Nissl, Glenner reaction, and histochemical fluorescence) indicated in the experimental group a progressive disappearance of the coerulean perikarya within 7 days postinjection. This lesion was permanent and did not induce any noradrenergic sprouting. 相似文献
54.
Which are the main features associated with taste loss in patients exposed to a wide range of drugs and diseases? In 100 consecutive patients admitted to a ward of internal medicine, we assessed taste complaints, performance status, alcohol and tobacco consumptions, diseases, drugs and laboratory data, measuring the electrical taste threshold as primary outcome. After adjusting for age, taste thresholds were not associated with sex, body mass index, tobacco, thrush, drugs, aliageusia and phantogeusia. Features associated with threshold increase included alcohol intake>or=10 gd-1, impaired performance status, complaint of taste loss, atrophic glossitis, cerebral disease, and an erythrocyte mean corpuscular volume. A multivariate analysis identified age, alcohol intake, complaint of loss or altered taste, mean corpuscular volume, and performance status as independent factors associated with taste loss. Inpatients may be screened for taste loss by a few features, to identify those for whom a nutritional intervention should be focused. 相似文献
55.
Sleep is the main behavioral state of the premature infant. In adult intensive care units, sleep deprivation has been reported as one of the major stressors. Developmental care (DC) aims to decrease stressful events in neonatal intensive care unit and support well-being. AIM: To assess whether DC is accompanied by changes in sleep in preterm neonates. METHODS: A prospective cross-over study included 33 preterm neonates [mean (S.D.): gestational age: 29.3 (1.8) weeks; birth weight: 1245 (336) g]. Polysomnography was performed in two randomly ordered 3-h periods with and without DC. A blinded electrophysiologist analyzed sleep. The total sleep time (TST) was the primary outcome, duration of active (AS), quiet (QS) and indeterminate sleep, and latency before sleep were the secondary outcomes. Non-parametric Wilcoxon tests and ANOVA were used. RESULTS: In DC condition vs. control: TST increased [in minutes, mean (S.E.M.): 156.2 (2.9) vs. 139.2 (4.6), p=0.002], with increase in AS [86.6 (3.7) vs. 77.0 (4.2), p=0.024] and in QS [47.1 (4.1) vs. 36.9 (4.2), p=0.015], and sleeping latency decreased (2.1 (0.7) vs. 10.5 (2.0), p=0.0005]. CONCLUSION: DC promoted sleep in our study. The impact of DC on the neuro-behavioral outcome needs futures studies. 相似文献
56.
Geeraerts T Albaladejo P Declère AD Duranteau J Sales JP Benhamou D 《The Journal of trauma》2004,56(4):845-849
BACKGROUND: Left ventricular ejection time (LVET) measured in central arteries is modified during hypovolemia. We compared modifications of the pulse wave in a central artery (carotid) and in a peripheral artery (digital) during central hypovolemia induced by lower body negative pressure (LBNP) in conscious volunteers. METHODS: Hypovolemia was simulated with progressive LBNP (baseline, -10, -20, and -30 mm Hg) in nine young healthy volunteers. The carotid arterial pressure waveform was recorded using a Millar tonometric method. The digital pulse wave was measured with a volume-clamp method (Finapres) and the stroke volume with a thoracic impedance method (Biomed). RESULTS: Mean arterial pressure did not change during LBNP. Compared with baseline values, heart rate increased significantly at the -30 mm Hg level (68 +/- 13 beats/min vs. 59 +/- 11 beats/min), and stroke volume decreased as soon as -10 mm Hg was achieved (113 +/- 41 mL vs. 127 +/- 35 mL). Both carotid and digital LVET decreased significantly at the -10 mm Hg level (337 +/- 26 and 339 +/- 24 ms vs. 360 +/- 35 and 361 +/- 24 ms, respectively). CONCLUSION: Peripheral LVET could reflect variation of central LVET during LBNP and be a reliable noninvasive parameter for monitoring hypovolemia. 相似文献
57.
58.
Immune repertoires of T or B cells are very often studied by Complementary Determining Region 3 (CDR3) spectratyping. However, data obtained with this method is usually subject to a biased eye analysis. We developed recently the ISEApeaks software package to retrieve and handle peak data from automated sequencers, from which CDR3 spectratype data is obtained. We describe a general strategy for CDR3 spectratype analysis based on two new specific modules and multivariate statistics. The first module addresses the crucial problem of peak smoothing. The second is a toolbox for the analysis of CDR3 spectratypes, which includes perturbation computation, recurrent peak finding, expansion assessment and datamining. To illustrate our approach, we assessed the complex TCRB repertoire modifications induced by Plasmodium berghei ANKA (PbA) infection. This global and exhaustive repertoire analysis approach is of general interest for T- and B-lymphocyte repertoire studies and is currently used in human cohorts in various pathologies and during clinical trials. 相似文献
59.
Diagnosis of hepatic fibrosis and cirrhosis by transient elastography in HIV/hepatitis C virus-coinfected patients 总被引:6,自引:0,他引:6
de Lédinghen V Douvin C Kettaneh A Ziol M Roulot D Marcellin P Dhumeaux D Beaugrand M 《Journal of acquired immune deficiency syndromes (1999)》2006,41(2):175-179
BACKGROUND: Chronic hepatitis C in HIV-infected patients is an increasing cause of death dependent on the development of liver fibrosis, which is currently assessed by liver biopsy despite its limitations. Liver stiffness measurement, a new noninvasive method, allows the evaluation of liver fibrosis. The aim of this prospective study was to assess the accuracy of liver stiffness measurement for the detection of fibrosis and cirrhosis in HIV/hepatitis C virus (HCV)-coinfected patients and to compare its accuracy with other noninvasive methods. METHODS: We studied 72 consecutive HIV patients with chronic hepatitis C who had a simultaneous liver biopsy and liver stiffness measurement by transient elastography (FibroScan; Echosens, Paris, France) for the assessment of liver fibrosis. RESULTS: Liver stiffness values ranged from 3.0 to 46.4 kilopascal. Liver stiffness was significantly correlated to fibrosis stage (Kendall tau-b = 0.48; P < 0.0001). The area under the receiver operating characteristic (AUROC) curve of liver stiffness measurement was 0.72 for F > or = 2 and 0.97 for F = 4. For the diagnosis of cirrhosis, AUROC curves of liver stiffness measurement were significantly higher than those for platelet count (P = 0.02), aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio (P = 0.0001), Aspartate aminotransferase-to-Platelet Ratio Index (APRI) (P = 0.01), and FIB-4 (P = 0.004). CONCLUSION: Liver stiffness measurement is a promising noninvasive method for the assessment of fibrosis in HIV-infected patients with chronic HCV infection. Its use for the follow-up of these patients should be further evaluated. 相似文献
60.
Arkadiusz Miazek Kornelia Macha Agnieszka aszkiewicz Adrien Kissenpfennig Bernard Malissen Pawel Kisielow 《European journal of immunology》2009,39(9):2596-2605
Linker for activation of T cells (LAT) is an adaptor molecule indispensable for development of αβ and γδ T lymphocytes. Surprisingly, using a new model of LAT‐deficient mice we found that despite arrested thymic development, a discrete population of cells with active Lat promoter, expressing Thy1 molecules, accumulated in peripheral lymphoid organs of homozygous (LatInv/Inv) mutant mice. By measuring frequencies of TCR gene rearrangements in conjunction with a panel of cell surface Ag, we dissected two subsets of these Thy1+ cells. Thy1dull cells expressed markers of NK lymphocytes and contained low frequency of TCR‐γ gene rearrangements without detectable TCR‐δ rearrangements. Thy1high cells resembled immature CD44+CD25+ thymocytes and contained high frequency of non‐productive TCR‐γ and TCR‐δ rearrangements, indicating that cells displaying molecular signatures of commitment toward γδ T‐cell lineage can develop and populate lymphoid tissues of LAT‐deficient mice. Phenotypically similar Thy1high cells were also found in lymph nodes of lymphocyte‐deficient (Rag2?/?) mice but not in T lymphocyte proficient, heterozygous Lat+/Inv mice suggesting that Thy1high cells of LAT‐deficient mice identified in this study accumulate in peripheral lymphoid organs as a result of congenital lymphopenia. 相似文献