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51.
52.
Akira Honda Tadashi Yoshida Naomi Tanaka Yasushi Matsuzaki Bingfang He Toshiaki Osuga M.D. Nobuaki Kobayashi Kazue Ozawa 《Journal of gastroenterology》1993,28(3):406-414
In Japan the composition of gallstones is changing rapidly from the once-predominant brownpigment stones to cholesterol ones.
The present work was undertaken to clarify the mechanism of cholesterol supersaturated bile production in Japanese patients
with cholesterol gallstones. In 26 non-obese and normolipidemic patients (11 with cholesterol gallstones, 8 with black- or
brown-pigment gallstones, 7 without gallstones) a liver biopsy and hepatic bile were surgically obtained under standardized
conditions. The cholesterol saturation of hepatic bile was significantly higher in cholesterol gallstone patients than in
gallstone-free controls (195 ±10 vs. 146 ±8%, respectively; P < 0.01). The microsomal activities of 3-hydroxy-3-methylglutaryl
coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme for cholesterol synthesis, cholesterol 7 α-hydroxylase, the rate-limiting
enzyme for bile acid synthesis, and 7 α-hydroxy-4-cholesten-3-one 12 α-hydroxylase (12 α-hydroxylase), the rate-limiting enzyme
for cholic acid synthesis, were assayed simultaneously in the same subjects. There were positive correlations between HMG-CoA
reductase and cholesterol 7 α-hydroxylase activities (Rs = 0.62, P < 0.005), and between cholesterol 7 α-hydroxylase and 12
α-hydroxylase activities (Rs = 0.44, P < 0.05) in all subjects, irrespective of the existence of gallstones. The activities
of the three rate-limiting enzymes did not differ significantly among the three groups (cholesterol stone, pigment stone and
stone-free). In conclusion, the cholesterol supersaturation of hepatic bile in nonobese and normolipidemic Japanese patients
with cholesterol gallstones does not result from an increased hepatic cholesterol synthesis or a decreased bile acid synthesis.
This study was supported in part by a Grant-in-Aid for Scientific Research (No. 02454226) from the Ministry of Education,
Science and Culture of Japan, and a grant from University of Tsukuba Project Research. 相似文献
53.
Maite M. Schroor Jogchum Plat Maurice C.J.M. Konings Ellen T.H.C. Smeets Ronald P. Mensink 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(5):1579-1585
Background and aimsExtensive research showed a diurnal rhythm of endogenous cholesterol synthesis, whereas recent research reported no diurnal rhythm of intestinal cholesterol absorption in males who consumed low-fat meals. Little is known about the acute effect of macronutrient consumption on cholesterol metabolism, and hence if meal composition may explain this absence of rhythmicity in cholesterol absorption. Therefore, we examined the effect of a high-fat, high-carbohydrate, and high-protein meal on postprandial intestinal cholesterol absorption and endogenous cholesterol synthesis in apparently healthy overweight and slightly obese males.Methods and resultsEighteen males consumed in random order an isoenergetic high-fat, high-carbohydrate, and high-protein meal on three occasions. Serum total cholesterol concentrations, cholesterol absorption markers (campesterol, cholestanol, and sitosterol), and cholesterol synthesis intermediates (7-dehydrocholesterol, 7-dehydrodesmosterol, desmosterol, dihydrolanosterol, lanosterol, lathosterol, zymostenol, and zymosterol) were measured at baseline (T0) and 240 min postprandially (T240). Meal consumption did not significantly change total cholesterol concentrations and cholesterol absorption marker levels (all p > 0.05). Serum levels of 7-dehydrocholesterol, lanosterol, lathosterol, zymostenol, and zymosterol decreased significantly between T0 and T240 (all p < 0.05). These decreases were not significantly different between the three meals (all p > 0.05), except for a larger decrease in dihydrolanosterol levels after the high-fat versus the high-carbohydrate meal (p = 0.009).ConclusionThe high-fat, high-carbohydrate, and high-protein meal did not significantly influence postprandial intestinal cholesterol absorption. Several cholesterol synthesis intermediates decreased postprandially, but the individual macronutrients did not differentially affect these intermediates, except for a possible effect on dihydrolanosterol.Trial registrationClinicalTrials.gov, NCT03139890. 相似文献
54.
目的探讨替米沙坦诱导大鼠肝细胞自噬对肝脏胆固醇代谢的影响及作用机制。方法将肝脏原代细胞分为正常对照组(Con)、替米沙坦1μmol/L组(Tel 1组)、替米沙坦3μmol/L组(Tel 3组)、替米沙坦10μmol/L组(Tel 10组)、替米沙坦10μmol/L联合PPARγ抑制剂GW 9662组(Tel+G组)。Tel 1、Tel 3、Tel 10组分别按1、3、10μmol/L浓度加入替米沙坦,Tel+G组加入10μmol/L替米沙坦及PPARγ抑制剂GW9662,培养24 h。检测肝细胞胆固醇浓度,Western blot法检测微管相关蛋白轻链3(LC3)、自噬蛋白区域(Beclin-1)、腺苷酸活化蛋白激酶(AMPK)、雷帕霉素靶分子(mTOR)表达水平。结果 Tel 3、Tel 10组胆固醇水平低于Con、Tel 1组(P<0.05)。Tel 1、Tel 3、Tel 10组LC3Ⅱ/Ⅰ比值、Beclin-1蛋白水平依次升高(P<0.05)。与Con、Tel 1组比较,Tel 3、Tel 10组p-AMPK/AMPK蛋白比值升高(P<0.05),p-mTOR/mTOR蛋白比值降低(P<0.05)。与Tel 10组比较,Tel+G组胆固醇水平、p-mTOR/mTOR蛋白比值升高(P<0.05),LC3II/I比值、p-AMPK/AMPK蛋白水平降低(P<0.05)。结论替米沙坦可通过诱导大鼠肝细胞自噬影响肝脏细胞胆固醇代谢,其机制可能与激活AMPK/mTOR途径和上调PPARγ有关。 相似文献
55.
本文观察近交系NJS小鼠红细胞变形能力及其与血清胆固醇的关系。以DXC—300型核孔膜红细胞变形能力测定仪测定小鼠的红细胞变形指数(EFI),同时以日立7150型血液自动生化分析仪测定血清胆固醇(CHO)含量,并以C57BL/6J正常小鼠作对照。结果表明:NJS/小鼠EFI(0.29±0.06)显著高于C57BL/6J小鼠(0.20±0.10,P<0.01),小鼠EFI与CHO水平呈正相关(r=0.785,P<0.01)。提示:红细胞变形能力受损可能在高胆固醇血症小鼠动脉粥样硬化的发病过程中起重要作用。 相似文献
56.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2020,30(10):1768-1776
Backgrounds and aimsPrevention of cardiovascular (CV) disease is considered a central issue in public health and great attention is payed to nutritional approaches, including consumption of functional foods to reduce CV risk in individuals without indications for anti-atherosclerotic drugs. Cholesterol efflux capacity (CEC) is an important anti-atherogenic property of HDL and a marker of CV risk. We evaluated the effect of a daily consumption of an innovative whole-wheat synbiotic pasta, compared to a control whole-wheat pasta, on serum ATP binding cassette G1 (ABCG1)-mediated CEC in healthy overweight or obese individuals.Methods and resultsStudy participants (n = 41) were randomly allocated to either innovative or control pasta, consumed daily for twelve weeks. Serum CEC was measured before and after the dietary intervention, by a well-established radioisotopic technique on Chinese Hamster Ovary Cells transfected with human ABCG1. The innovative synbiotic pasta consumption was associated to a significantly higher post treatment/baseline ratio of ABCG1-mediated CEC values with respect to control pasta (mean ratio 1.05 ± 0.037 and 0.95 ± 0.042 respectively, p < 0.05). Analysis of the relationship between ABCG1-mediated CEC and glycemia, homocysteine, total folates and interleukin-6 showed specific changes in the correlations between HDL function and glycemia, oxidative and inflammatory markers only after synbiotic pasta consumption.ConclusionThis is the first report on serum CEC improvement obtained by a new synbiotic functional pasta consumption, in absence of lipid profile modifications, in overweight/obese participants. This pilot study suggests that a simple dietary intervention can be a promising approach to CV preservation through improving of athero-protective HDL function. 相似文献
57.
58.
给54积Wistar雄性大鼠自由饮用染氟水,浓度分别为0.6(对照组),100和200mg/L,于染氟后第2,4,6周分批处死,测血清和肝组织的胆固醇,甘油三酯含量。结果显示,染氟第6周,染氟组大鼠血清胆固含量显著增高,肝组织胆固醇含量显著降低。200mg/L摄氟组大鼠血清甘油三酯含量在第4周显著降低,肝组织甘油三酯含量在第6周显著降低。提示,氟可影响大鼠脂代谢,引起高胆固醇血症。 相似文献
59.
Kalle Hakala Pekka Luukkonen Matti Vuoristo Heikki Järvinen Tatu A. Miettinen 《Journal of hepatology》1997,26(6):1306-1312
Background: Previous studies suggest only minor changes in bile acid metabolism after panproctocolectomy with ileal pouch construction.Aims/Methods: To investigate these changes further, we studied cholesterol absorption and serum, biliary and fecal non-cholesterol sterols and lipids in 12 ileal pouch patients and 10 controls.Results: In patients, cholesterol absorption was markedly reduced and was associated with low serum total and LDL cholesterol and LDL triglyceride levels, but surprisingly, cholesterol synthesis, as indicated by sterol-balance data or serum cholesterol precursor levels, was within low normal limits. The high proportions of serum plant sterol to cholesterol, particularly that of campesterol, were not related to cholesterol absorption, but were attributable to a markedly reduced biliary cholesterol secretion. Interestingly, in these patients the fractional absorption of campesterol was normal, whereas that of sitosterol, like cholesterol, was reduced and was positively related to the intestinal influx of cholesterol. The patients' serum cholestanol proportion was normal, but the proportion of the cholestanol formed during intestinal passage was significantly reduced (17.9% vs 65.2% in controls).Conclusions: Thus ileal pouch patients are characterized by sterol malabsorption, lowered serum total and LDL-cholesterol levels, but unexpectedly without any increase in cholesterol synthesis. The lack of high serum cholestanol, shown earlier frequently in unoperated patients with ulcerative colitis, may indicate reversible cholestasis, a finding deserving further exploration. 相似文献
60.
Summary Synovial effusions containing cholesterol crystals are uncommon. Most of the few reported cases have been found in patients with seropositive rheumatoid arthritis. In vitro studies, as well as an animal model, have suggested that cholesterol crystals could have a role in inflammation of the joints. In this report we present a case of seronegative arthritis, complicated by large carpal synovial cysts which contained numerous cholesterol crystals. The long-term presence of the cysts, without evidence of joint destruction, suggests that cholesterol crystal formation is probably a rare epiphenomenon, rather than a harbinger of inflammation. 相似文献