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排序方式: 共有374条查询结果,搜索用时 15 毫秒
1.
In this paper, the authors describe some of the complexities of collecting and presenting data on race and ethnicity based on the experiences of the Bureau of the Census. Different methods of data collection, different content and format of questions, and different definitions make it difficult to collect consistent race and ethnic data across data systems. The Bureau of the Census experiences have shown that changing ethnic self-identity and concepts, intent of the question, consistency of reporting, and the classification of persons of mixed racial parentage affect the quality of the data. These are some of the issues that must be addressed as statistical agencies and researchers seek to provide comparable race and ethnic data. 相似文献
2.
James M. McKenney Pharm.D. 《Pharmacotherapy》1993,13(4):340-352
Hypertension and diabetes appear to increase coronary heart disease risk in part by causing an abnormality in lipid metabolism. Most affected are patients with familial dyslipidemic hypertension (FDH) and noninsulin-dependent diabetes mellitus (NIDDM). The lipid disorders most often encountered in these patients are increased levels of triglycerides, very low-density lipoprotein (VLDL) cholesterol, and small, dense low-density lipoprotein (LDL) cholesterol, and low levels of high-density lipoprotein (HDL) cholesterol. These abnormalities appear to result from increased hepatic secretion of VLDL particles due to increased concentrations of free fatty acids and glucose, reduced VLDL clearance due to reduced activity of lipoprotein lipase, and reduced LDL clearance due to glycosylation of ligand proteins. Treatment of the dyslipidemia associated with FDH should follow the guidelines from the National Cholesterol Education Program. Treatment in men and women with NIDDM should be considered when LDL cholesterol levels are 130 mg/dl or above, triglyceride levels are 200 mg/dl or above, or non-HDL cholesterol levels are 160 mg/dl or greater. Aggressive lifestyle changes should be initiated first, including weight loss in obese patients, control of glucose levels in those with NIDDM, avoidance of antihypertensive drugs that may worsen lipid levels in patients with FDH, and eating a diet restricting saturated fat and cholesterol. Addition of lipid-altering drugs should be considered if such changes do not achieve effective lipid control. The agent should be tailored to the patient's lipid profile, in general by using bile acid resins, niacin, or reductase inhibitors to lower LDL cholesterol and gemfibrozil or niacin to lower triglycerides. Niacin should be avoided in patients with NIDDM. 相似文献
3.
James McKenney 《American journal of health-system pharmacy》2003,60(10):995-1005
The efficacy and safety profiles of various forms of niacin for treating dyslipidemia are described. Niacin is well recognized for treating dyslipidemia in adults and has been shown to be effective in reducing coronary events. It has a broad range of effects on serum lipids and lipoproteins, including lowering total cholesterol, low-density-lipoprotein (LDL) cholesterol, and triglycerides. Niacin is the most effective lipid-modifying drug for raising high-density-lipoprotein (HDL) cholesterol levels and has been shown to lower Lp(a) lipoprotein. Niacin reduces triglycerides and very-low-density-lipoprotein and LDL cholesterol synthesis, primarily by decreasing fatty acid mobilization from adipose tissue. Niacin appears to raise HDL cholesterol by reducing hepatic apolipoprotein A-l clearance and enhancing reverse cholesterol transport. Niacin is metabolized through a conjugation or nicotinamide pathway. Standard immediate-release niacin is metabolized primarily through the conjugation pathway, which results in a high frequency of flushing. Long-acting niacin is metabolized through the nicotinamide pathway, which results in less flushing but increases the risk of hepatotoxicity. Extended-release niacin has a more balanced metabolism and causes fewer of both types of adverse effects. Improved serum lipid levels during niacin therapy have been associated with clinical and angiographic evidence of reduced coronary artery disease, especially when combined with statins. Niacin is particularly useful for managing high triglyceride and low HDL cholesterol levels as well as the lipid abnormalities associated with metabolic syndrome, including those commonly encountered in patients with diabetes. Several niacin products are available with significant differences in their safety and efficacy profiles. Health care providers must consider the differences between agents when recommending niacin for dyslipidemia treatment. 相似文献
4.
James M McKenney Michael H Davidson Charles L Shear James H Revkin 《Journal of the American College of Cardiology》2006,48(9):1782-1790
OBJECTIVES: This study sought to evaluate the efficacy and safety of torcetrapib in patients with low high-density lipoprotein cholesterol (HDL-C) levels receiving background atorvastatin. BACKGROUND: Elevating HDL-C levels may reduce the residual cardiovascular risk that is observed in patients treated with statin therapy. Torcetrapib (a cholesteryl ester transfer protein inhibitor) increases HDL-C and decreases low-density lipoprotein cholesterol (LDL-C). METHODS: This was a multicenter, double-blind, randomized trial. Patients with below-average HDL-C (men <44 mg/dl; women <54 mg/dl) who were eligible for statin therapy according to National Cholesterol Education Program Adult Treatment Panel III guidelines or who had LDL-C >130 mg/dl at screening entered an 8-week run-in period with atorvastatin 20 mg/day before randomization (n = 174) to torcetrapib 10, 30, 60, or 90 mg/day or placebo for 8 weeks. Atorvastatin was continued during treatment with torcetrapib. RESULTS: After 8 weeks, the percent change from baseline with torcetrapib (least-squares mean difference from placebo) ranged from 8.3% to 40.2% for HDL-C (p < or = 0.0001 for 30-mg and higher doses) and from 0.6% to -18.9% for LDL-C (p < 0.01 for 60-mg and 90-mg doses). Particle size for both HDL and LDL increased with torcetrapib. The incidence of all-causality and treatment-related adverse events was similar across placebo and torcetrapib treatment groups with no evidence of a dose-related response. In some treatment groups, small increases in systolic and diastolic blood pressures were noted. CONCLUSIONS: In statin-eligible patients, torcetrapib plus background atorvastatin resulted in substantial, dose-dependent increases in HDL-C, accompanied by additional decreases in LDL-C beyond those seen with atorvastatin alone. Torcetrapib plus atorvastatin was generally well tolerated. 相似文献
5.
P A McKenney C S Apstein L A Mendes G P Connelly G S Aldea R J Shemin R Davidoff 《The American journal of cardiology》1999,84(8):914-918
Diastolic dysfunction is common after coronary artery bypass surgery, and we hypothesized that left ventricular (LV) hypertrophy associated with aortic stenosis may lead to worsening LV diastolic function after aortic valve replacement for aortic stenosis. Transesophageal echocardiographic LV images and simultaneous pulmonary arterial wedge pressures were used to define the LV diastolic pressure cross-sectional area relation before and immediately after aortic valve replacement for aortic stenosis in 14 patients. In all patients, LV diastolic chamber stiffness increased, as evidenced by a leftward shift in the LV diastolic pressure cross-sectional area relation. At comparable LV filling (pulmonary arterial wedge) pressures the mean LV end-diastolic cross-sectional area preoperatively was 17.9 +/- 1.7 cm2, but decreased by 32% after aortic valve replacement to 12.1 +/- 1.2 cm2 (p = 0.0001). In conclusion, after aortic valve replacement, diastolic chamber stiffness increased in all patients. 相似文献
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8.
Charles R. Kiefer James B. McKenney Jane F. Trainor Richard W. Lambrecht Herbert L. Bonkovsky Lawrence M. Lifshitz C. Robert Valeri L. Michael Snyder 《The American journal of pathology》1998,153(3):703-708
To further the understanding of oxidative effects on inflammation injury to muscle fiber structure, fluorescent imaging analysis of human striated muscle tissues from a variety of inflammatory or postinflammatory etiologies was undertaken in a search for accumulated coproporphyrin, a red autofluorescent byproduct of heme biosynthesis that would theoretically be formed under oxidative insult. Using a differential excitation method of in situ analysis, porphyrin autofluorescence was detected in intact fibers within the context of the yellow autofluorescent subsarcolemmal lipofuscin granules. Relative measurements of porphyrin concentration in the granules from different patients indicated that the acute/subacute inflammatory specimens grouped significantly higher than the more chronic inflammatory and nonpathological specimens. Myoglobin was also found to be associated with the granules. Myoglobin heme iron could potentially serve as a Fenton reagent for the intracellular generation of hydroxyl radicals, which are responsible for the oxidation of the porphyrinogens. High-performance liquid chromatography analysis of extracted dense particles revealed coproporphyrin as the sole porphyrin present. The observation of coproporphyrin within lipofuscin granules, previously unreported, suggests that lipofuscin accumulation in striated muscle may begin under conditions of acute oxidative stress, as marked by the oxidation of extramitochondrial porphyrinogens that are immediately incorporated into the granules. 相似文献
9.
Peikert T Finkielman JD Hummel AM McKenney ME Gregorini G Trimarchi M Specks U 《Arthritis and rheumatism》2008,58(5):1546-1551
OBJECTIVE: Antineutrophil cytoplasmic antibodies (ANCA) binding to neutrophil elastase (NE) and proteinase 3 (PR3) are detectable in most patients with cocaine-induced midline destructive lesions (CIMDL), but the pathogenic role and antigen specificity of these antibodies are unknown. This study was undertaken to assess the effects of NE ANCA on the enzymatic activity of NE, to determine whether these antibodies interfere with the physiologic effect of secretory leukoprotease inhibitor (SLPI), and to investigate the antigen specificity of both NE and PR3 ANCA in patients with CIMDL. We also compared the binding of PR3 ANCA in patients with CIMDL with that in patients with Wegener's granulomatosis (WG). METHODS: PR3 ANCA and NE ANCA were detected by capture enzyme-linked immunosorbent assays (ELISAs) and by indirect immunofluorescence. IgG was purified from the patients' sera, and the influence of NE ANCA on the enzymatic activity of NE and on the inhibitory activity of SLPI was investigated by determining the hydrolysis of N-methoxysuccinyl-Ala-Ala-Pro-Val p-nitroanilide by NE. RESULTS: IgG from NE ANCA-positive sera of patients with CIMDL inhibited the enzymatic activity of NE and did not interfere with the activity of SLPI. In contrast to the findings in WG sera, measurement of PR3 ANCA in CIMDL sera showed only fair to moderate concordance between the 2 different capture ELISAs. Cross-inhibition experiments demonstrated that NE ANCA and PR3 ANCA represent distinct autoantibodies in patients with CIMDL. CONCLUSION: The functional effects of NE ANCA on the enzymatic activity of NE or on the activity of SLPI cannot be implicated in the pathogenesis of CIMDL. The autoimmune reaction that targets neutrophil serine proteases in patients with CIMDL is frequently directed against more than one antigen. The ANCA response, including the reactivity of PR3 ANCA, in patients with CIMDL differs from what has been described in patients with WG. 相似文献
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