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排序方式: 共有1227条查询结果,搜索用时 15 毫秒
91.
Plestina S Pulanić R Kralik M Plestina S Samarzija M 《Wiener klinische Wochenschrift》2005,117(19-20):711-717
PURPOSE: The aim of the study was to examine the role of Doppler ultrasonography of the portal vein in predicting esophageal variceal bleeding in patients with liver cirrhosis and portal hypertension by comparing the ultrasound data to the endoscopic findings. PATIENTS AND METHODS: 99 patients with liver cirrhosis and esophageal varices underwent color Doppler ultrasonography and esophagogastroduodenoscopy. The following portal hemodynamic parameters were analyzed: diameter and cross-sectional area, mean blood flow velocity, blood flow volume, perfusion pressure gradient, congestion index, and platelet count-to-spleen diameter ratio. Variceal characteristics, the size and the presence of red signs, were determined by endoscopic examination. RESULTS: Patients with variceal red signs had significantly higher values of portal diameter (1.538 +/- 0.246 vs. 1.243 +/- 0.167), cross-sectional area (1.286 +/- 0.448 vs. 0.945 +/- 0.256), blood flow volume (965.520 +/- 432.728 vs. 625.117 +/- 320.999) and congestion index (0.165 +/- 0.068 vs. 0.126 +/- 0.051) than patients without red signs, while the perfusion pressure gradient (0.260 +/- 0.087 vs. 0.447 +/- 0.271) and the platelet-to-spleen ratio (522.424 +/- 222.823 vs. 708.921 +/- 230.769) were lower. The same pattern of differences between the ultrasound parameters was found in patients with large varices comparing ones with red signs to the ones without them (diameter, 1.567 +/- 0.234 vs. 1.258 +/- 0.175; cross-section, 1.313 +/- 0.455 vs. 1.061 +/- 0.264; flow volume, 988.195 +/- 443.353 vs. 739.423 +/- 414.281; congestion index, 0.171 +/- 0.067 vs. 0.130 +/- 0.058; perfusion pressure gradient 0.247 +/- 0.078 vs. 0.501 +/- 0.379 and platelet-to-spleen ratio 479.930 +/- 184.302 vs. 699.094 +/- 316.171). Differences in values of ultrasonographic parameters were less obvious among groups of patients with different variceal sizes: only the diameter, cross-sectional area and blood flow volume were significantly different. The mean blood flow velocity did not depend on the variceal size or on the presence of red signs. The sensitivities and specificities of the analyzed parameters were 60-80% and 48.6-78.4%, respectively. CONCLUSIONS: Results suggest that color Doppler ultrasonography is a useful noninvasive method for evaluating the risk of esophageal variceal bleeding in patients with liver cirrhosis. 相似文献
92.
Sale S Sung R Shen P Yu K Wang Y Duran GE Kim JH Fojo T Oefner PJ Sikic BI 《Molecular cancer therapeutics》2002,1(3):215-225
The goal of this study was to determine the prevalence of sequence variants in the class I beta-tubulin (clone m40) gene and their occurrence in human tumors and cancer cell lines. DNA was isolated from 93 control individuals representing a wide variety of ethnicities, 49 paclitaxel-naive specimens (16 ovarian cancers, 17 non-small cell lung cancers, and 16 ovarian cancer cell lines), and 30 paclitaxel-resistant specimens (9 ovarian cancers, 9 ovarian cancer cell lines, and 12 ovarian cancer xenografts in nude mice). Denaturing high-performance liquid chromatography and direct sequence analysis detected two silent polymorphisms in exon 4, Leu217Leu (CTG/CTA) and Gly400Gly (GGC/GGT), with minor allele frequencies of 17 and 0.5%, respectively. Five nucleotide substitutions and one single-base deletion were detected in introns 1, 2, and 3 and in the 3' untranslated region. Analysis of 49 paclitaxel-naive and 30 paclitaxel-resistant specimens revealed no additional polymorphisms in the coding region. In addition, no amino acid replacements were found in chimpanzee, gorilla, and orangutan in comparison to human. Our data demonstrate a very high degree of sequence conservation in class I beta-tubulin, suggesting that all residues are important in tubulin structure and function. Individual variation in response to treatment with paclitaxel is not likely to be caused by genetic variations in the beta-tubulin drug target. Moreover, acquired mutations in class I beta-tubulin are unlikely to be a clinically relevant cause of drug resistance. 相似文献
93.
From cats prepared for chronic pollygraphic recording of sleep patterns, records were obtained for 8 hr, after (1) intracerebroventricular (i.c.v.) injection of artificial cerebrospinal fluid (aCSF), day 1; (2) i.c.v. injection of interleukin-1 (Il-1), day 2; and (3) injection of aCSF, day 3. Three doses of Il-1 were tested. The dose of 40 nmol totally inhibited sleep, whereas the dose of 10 nmol slightly prolonged sleep. The dose of 20 nmol of Il-1 elicited sleep and a body temperature increase. Total sleep (TS) time was significantly increased, due mainly to the significant increase in non-REM (NREM) sleep as compared to control day 1. REM sleep was also increased, but this increase did not reach statistical significance. Wakefulness (W) was significantly reduced. At this time cats were febrile. On day 3, a further significant increase in TS occurred. NREM was significantly increased compared with day 1, whereas the increase in REM sleep was significant compared to both day 1 and day 2. At this time body temperature was normal. The increase in REM sleep on days 2 and 3 resulted entirely from the significant increase in the number of REM periods. The results show that Il-1 at a dose of 20 nmol has sleep-promoting effects on NREM and REM sleep concomitant with pyrogenic effects. These two responses differed in their time courses and were not correlated (correlation coefficients were all nonsignificant). 相似文献
94.
95.
Monaco SE Shuai Y Bansal M Krasinskas AM Dacic S 《American journal of clinical pathology》2011,135(4):619-627
Two promising ancillary tests used in the diagnosis of mesothelioma include GLUT-1 immunohistochemical analysis and fluorescence in situ hybridization (FISH) testing for the p16 deletion. This study compared the diagnostic usefulness of p16 FISH and GLUT-1 immunohistochemical analysis in the diagnosis of mesothelial proliferations in 158 cases with a diagnosis of benign (45.4%), atypical (10.4%), or malignant/mesothelioma (44.2%). Of the 70 benign cases, none had a deletion of p16 and 5 cases (7%) were positive for GLUT-1. Of the 68 mesotheliomas, 40 (59%) had a deletion of p16 (sensitivity, 59%; specificity, 100%) and 27 (40%) were positive for GLUT-1 (sensitivity, 40%; specificity, 93%). GLUT-1 showed lower sensitivity in pleural (56% vs 70%) and peritoneal (29% vs 51%) mesotheliomas (P = .004). Our results demonstrate that p16 FISH is a more sensitive and specific test than GLUT-1 immunohistochemical analysis and can be a more reliable ancillary tool to support the diagnosis of mesothelioma. 相似文献
96.
García JJ Hunt JL Weinreb I McHugh JB Barnes EL Cieply K Dacic S Seethala RR 《Human pathology》2011,42(12):2001-2009
Oncocytic mucoepidermoid carcinoma poses diagnostic challenge because of its histologic overlap with other oncocytic salivary gland lesions, including Warthin tumor. Although the prognostic value of the t(11;19) MECT1-MAML2 fusion gene has been established in mucoepidermoid carcinoma, its diagnostic use in discriminating oncocytic mucoepidermoid carcinoma from histologic mimics is unexplored. We evaluated the translocation status in 14 cases of oncocytic mucoepidermoid carcinoma using a MAML2-11q21 break-apart probe spanning the entire chromosome region of the MAML2 gene and correlated these findings with clinicopathologic parameters including age, sex, stage, predominant growth pattern, grade, and p63 immunostaining pattern. All oncocytic mucoepidermoid carcinomas were parotid tumors with a mean patient age of 54.6 years (range, 9-85) and a female to male ratio of 5:2. Grade distribution was as follows: low grade, 9; intermediate grade, 2; and high grade, 3. The histologic patterns observed were as follows: solid, 4; cystic, 8 (of these, 5 had Warthin-like lymphoid stroma); and mixed, 2. Solid oncocytic mucoepidermoid carcinomas showed a diffuse p63 staining pattern, whereas cystic oncocytic mucoepidermoid carcinomas showed staining of the outer layer of intermediate cells ranging from a bilayer to areas of complex multilayering and plaque-like proliferation. Ten (71%) of the 14 cases showed a MAML2 rearrangement by fluorescence in situ hybridization. No correlation was seen between rearrangement status and histologic grade, growth pattern, or p63 staining pattern. However, we demonstrate that the presence of MAML2 rearrangement can be used as supportive evidence to distinguish oncocytic mucoepidermoid carcinoma from other oncocytic lesions. 相似文献
97.
Steiner H Erickson SJ MacLean P Medic S Plattner B Koopman C 《Child psychiatry and human development》2007,38(2):107-119
Objective Although there are extensive data on the relationship between personality and stress reactivity in adults, there is little
comparable empirical research with adolescents. This study examines the simultaneous relationships between long term functioning
(personality, defenses) and observed stress reactivity (affect) in adolescents.
Methods High school students (N = 169; mean age 16; 73 girls) were asked to participate in two conditions of the Stress Induced Speech Task (SIST): Free
Association and Stressful Situation. Immature and mature defenses, distress and restraint personality dimensions, and negative
and positive affect were examined.
Results Greater reported use of immature defenses was significantly associated with negative affect, whereas greater reported use
of mature defenses was significantly associated with greater positive affect. Although personality style was also a significant
predictor of negative affect across two out of three conditions, defenses were better overall predictors of affect than were
personality dimensions. Gender was also a significant predictor of negative affect, wherein girls reported more negative affect
than boys.
Discussion Defenses and personality style predict affective response during a moderately stressful task. Immature defenses and, to a
lesser extent, the distress personality dimension predict mobilization of negative affect, whereas mature defenses predict
the reporting of positive affect. These results relate to processes central to psychotherapy: defensive responding, personality
style, and affective reactivity during the recounting of stressful events. 相似文献
98.
99.
100.
Plasma and erythrocyte phospholipid fatty acid profile in professional basketball and football players 总被引:1,自引:0,他引:1
Jasna Tepsic Vesna Vucic Aleksandra Arsic Vera Blazencic-Mladenovic Sanja Mazic Marija Glibetic 《European journal of applied physiology》2009,107(3):359-365
The effect of intensive long-term physical activity on phospholipid fatty acid (FA) composition has not been studied thoroughly. We determined plasma and erythrocyte phospholipid FA status of professional basketball and football players. Our results showed differences in plasma FA profile not only between sportsmen and sedentary subjects, but also between two groups of sportsmen. Plasma FA profile in basketball players showed significantly higher proportion of n-6 FA (20:3, 20:4, and 22:4) and total polyunsaturated FA (PUFA) than controls, while football players had higher palmitoleic acid (16:1) than basketball players and controls. Total PUFA and 22:4 were also higher in basketball than in football players. Erythrocyte FA profile showed no differences between football players and controls. However, basketball players had higher proportion of 18:0 than controls, higher saturated FA and lower 18:2 than two other groups, and higher 22:4 than football players. These findings suggest that long-term intensive exercise and type of sport influence FA profile. 相似文献