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991.
C M Peterson L Jovanovic-Peterson J L Mills M R Conley R H Knopp G F Reed J H Aarons L B Holmes Z Brown M Van Allen 《American journal of obstetrics and gynecology》1992,166(2):513-518
This study examined changes in cholesterol, triglycerides, body weight, and blood pressure during pregnancy in 312 diabetic and 356 control women recruited within 21 days after conception. Cholesterol values rose in both groups but were significantly lower in diabetic women at each time point (166 vs 178 mg/dl at week 12, p = 0.0004). Triglyceride values also rose in both groups. Triglyceride levels did not differ between groups up to week 8 of gestation, but by weeks 10 to 12 they were significantly lower in diabetic women than in controls (75 vs 89 mg/dl at week 12, p = 0.0004). Although they were no heavier at entry, diabetic women gained significantly more weight between weeks 6 and 8 (p less than 0.001), resulting in a mean difference between groups of 1 kg. Systolic blood pressure increased steadily and significantly in the diabetic but not the control women (115.8 +/- 16.2 SD vs 109.3 +/- 11.8 mm Hg, p = 0.0006 at term). Diastolic blood pressure was higher in diabetic women on entry (70.7 vs 67.3 mm Hg, p = 0.0006) and throughout gestation. Significant correlations were found in the diabetic group between maternal blood pressure and lipids and infant birth weight. These newly found differences in cholesterol and triglyceride levels, weight gain, and blood pressure between type I diabetic and control women during gestation may have long-term cardiovascular implications. 相似文献
992.
H Kohn K N Sawhney P LeGall J D Conley D W Robertson J D Leander 《Journal of medicinal chemistry》1990,33(3):919-926
We recently reported the potent anticonvulsant activity of (R,S)-alpha-acetamido-N-benzyl-alpha-phenylacetamide (2b). Selectively substituted derivatives of this compound have now been prepared (23 examples) and evaluated in the maximal electroshock seizure (MES) and horizontal screen (tox) tests in mice. In several key cases, replacement of the alpha-phenyl substituent in 2b by a relatively small, electron-rich, heteroaromatic moiety led to a substantial improvement in the anticonvulsant potency of the drug candidate. The most active compounds were (R,S)-alpha-acetamido-N-benzyl-2-furanacetamide (2g) and (R,S)-alpha-acetamido-N-benzyl-2-pyrroleacetamide (2i). After ip administration, the MES ED50 values for 2g (10.3 mg/kg) and 2i (16.1 mg/kg) compared well with phenytoin (9.50 mg/kg). Evaluation of the two individual enantiomers of 2g demonstrated that the anticonvulsant activity resided in the R stereoisomer. The low ED50 value (3.3 mg/kg) for (R)-2g contributed to the large protective index (TD50/ED50) observed for this drug candidate, which approached that of phenytoin. 相似文献
993.
994.
M J Conley A S Wechsler R W Anderson H N Oldham D C Sabiston R A Rosati 《Circulation》1977,55(1):158-163
Operative mortality for the first 787 patients who underwent aortocoronary bypass at Duke University Medical Center was 9.7%. Within 699 patients who underwent elective bypass only, operative mortality was 8.8% before January 1, 1972, and 5.4% subsequently. This apparent variation in operative mortality over time was largely a consequence of changing patterns of patient selection, i.e., a two- to three-fold decrease in the prevalence of ventricular dysfunction. Since January 1, 1972, operative mortality for 444 patients with mild or no heart failure who underwent elective bypass only was 5.0%. The 55 patients with left main disease had 12.7% operative mortality. In the 192 patients without left main disease who had one- or two-vessel disease, operative mortality was 1.0%, whereas, 197 patients with three-vessel disease had a 6.6% operative mortality. The 103 patients with three-vessel disease less than 50 years of age underwent operation with a 2.9% mortality. Although these results demonstrate that selected patients may undergo operation with a mortality approaching 1%, it is not clear that only such low risk patients should be offered surgery. Accurate estimates of benefits and risks of aortocoronary bypass surgery are necessary in the management of specific patients. 相似文献
995.
996.
Marguerite McMillan Jackson RN PhD CIC FAAN 《American journal of infection control》1997,25(6):520-528
Designing and performing focused studies is part of the regular work of infection surveillance, prevention, and control, and the methodology of a prevalence survey used in this practice forum will be familiar to many infection control professionals. A practical example of a focused study to evaluate cost savings from extending intravenous catheter site and administration set change frequency from 72 hours to 96 hours illustrates the steps required. Suggested references for additional information are included at the end of the article. 相似文献
997.
The clastogenic effect of melphalan, an alkylating agent frequentlyused in chemotherapy, was investigated using chromosomes fromhuman lymphocytes, two and three cell cycles after treatmentin vitro. Chromosome aberrations were much more frequent thanchromatid type anomalies. Unbalanced rearrangements, i.e. deletions,dicentrics and complex rearrangements (in decreasing order ofoccurrence), were quite frequent and balanced rearrangements,such as reciprocal translocations and inversions, were quiterare. Deletions principally affected chromosomes 9, 5, 7 and11. By comparison to the results obtained at first divisionafter treatment, the relative frequencies of del(5) and del(20)increased with the number of cell divisions. Thus, these deletionswere poorly eliminated by selection. This finding may be relatedto the fact that del(5) and del(20) are frequently observedin premalignant haemopathies.
1To whom correspondence should be addressed 相似文献
998.
R G Hoffman D J Speelman D A Hinnen K L Conley R A Guthrie R K Knapp 《Diabetes care》1989,12(3):193-197
In this study, 18 type I (insulin-dependent) diabetic subjects aged 22-35 yr (mean age 29.3) and within 10 yr of diagnosis (mean 7.7) performed a battery of cognitive and psychomotor tasks under conditions of hypoglycemia (50 mg/dl), normoglycemia (100 mg/dl), and hyperglycemia (300 mg/dl). Blood glucose levels during testing were precisely maintained at the preselected level via a Biostator insulin/glucose-infusion system. The order of glycemic level was counterbalanced across subjects in a single-blinded design. Performance on tasks requiring visual tracking, visuomotor speed, concentration, and planning ability (pursuit rotor and trails B) were significantly impaired under conditions of hypoglycemia compared with normoglycemic levels. Visual reaction time was not significantly impaired under conditions of hypoglycemia or hyperglycemia. 相似文献
999.
1000.