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1.
Andrew R. Hoellein MD Christopher A. Feddock MD Charles H. Griffith III MD MSPH John F. Wilson PhD Donald R. Barnett MD MSPH Pat F. Bass III MD MS T. Shawn Caudill MD MSPH 《Journal of general internal medicine》2004,19(5P2):562-565
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education. 相似文献
2.
Using data from the National Health and Nutrition Examination Survey (NHANES II) 1976-1980, we demonstrate how cross-sectional total serum cholesterol surveillance data can be used by an individual to assess current and future personal cholesterol risk status. We propose statistical models, based on a person's current measured cholesterol level and the relationship between cross-sectional age and cholesterol percentile estimates, that will allow prediction of future cholesterol levels or the age at which specified cholesterol risk levels will be reached if no cholesterol-altering intervention is taken. These models incorporate the observed variation in the NHANES II data and expected intraperson biological variation and intralaboratory analytical variation. We illustrate the adequacy of the models using data from the longitudinal Framingham Study. 相似文献
3.
4.
Malignant mixed Müllerian tumor is a rare neoplasm that occurs most frequently in elderly patients. It is characterized by a mixture of malignant epithelial and sarcomatous components. Little has been published about Papanicolaou smear findings pertaining to malignant mixed Müllerian tumors. We present our experience, with an emphasis on cytologic detail. Nine patients (median age, 65 yr) met our study criteria. All available smears and surgical specimens were reviewed. Four smears were positive for malignancy, with a sensitivity of 44% (3 adenocarcinoma, and 1 squamous-cell carcinoma, small-cell type). The results of our study showed that Papanicolaou smear findings pertaining to malignant mixed Müllerian tumors are seen in patients with advanced-stage disease with involvement of the lower uterine segment or cervix. The usual finding is large numbers of high-grade epithelial malignant cells in a necrotic background. The mesenchymal component rarely sheds cells visible on Papanicolaou smear. 相似文献
5.
An in vitro study was conducted to quantitatively measure the depth of root surface removal using curettes of standardized sharpness and with definite stroke number. Extracted periodontally healthy teeth from patients 10 to 15, 16 to 25, and 26 to 40 years old had periodontal ligament remnants removed with dry gauze before being secured in a vertical position during root planing. The force applied to the root surface was measured with a tension load cell. The "bright line" test was used to assess curette sharpness. After histologic processing, the thickness of cementum adjacent to the root defect, the cementum (if any) in the root defect, total amount of cementum removed, and depth of root defect were measured by a microscopic ocular grid. Teeth from each age range were evenly distributed into 6 groups of 10 teeth each. In the majority of teeth from the 20 stroke group through the 70 stroke group, complete cementum removal was observed at the site of planing. However, in some sections from each group, fragments of cementum remained on the root surface. A positive relationship (r/s = 1) was found between the number of strokes and the force applied to the root surface and the mean depth of defect (P less than 0.05). However, an inverse relationship existed between mean force per stroke and mean defect depth (r/s = -.99) such that as mean force per stroke increased, the mean defect depth decreased. As the root surface became smoother with an increasing number of strokes, the forces increased and were more consistent.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
7.
Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
8.
Dr. Timothy Shawn Caudill MD Eric Charles Westman MD Donald R. Holleman MD Eugene C. Rich MD 《Journal of general internal medicine》1993,8(9):515-516
To test an educational intervention’s effect on improving detection of glaucoma by direct ophthalmoscopy, 14 medicine residents
examined five patients, two with ophthalmoscopic changes of glaucoma and three with normal fundi. The residents observed a
standardized slide/narrative educational intervention reviewing glaucomatous ophthalmoscopic changes and then re-examined
the same patients eight to 12 weeks later. The intervention’s odds of improving residents’ diagnostic impression were significant
(OR=2.2; 95% CI=1.3–36), with significant improvement in sensitivity (p=0.02) and a trend toward improved specificity. These
findings confirm that the diagnosis of glaucomatous ocular changes on eye examinations by medicine residents can be improved
with a brief educational intervention.
Presented in abstract form at the annual meeting of the Society of General Internal Medicine, Medical Education Section, April
29–May 1, 1992, Washington, DC, and at the Southern regional meeting of the Society of General Internal Medicine, Medical
Education Section, January 29–31, 1992, New Orleans, Louisiana. 相似文献
9.
Influence of oxygen tension on the viscoelastic behavior of red blood cells in sickle cell disease 总被引:2,自引:0,他引:2
Although the rheological behavior of sickle cell suspensions and of hemoglobin S solutions is known to be strongly dependent on oxygen tension (PO2), little data exist concerning the influence of PO2 on the viscoelasticity of individual HbSS RBC. We have used micropipette aspiration techniques to test the deformation response of both HbSS and control HbAA RBC over a wide range of PO2 at 23 degrees C. Sickled, spiculed HbSS cells were present for PO2 approximately less than 35 mm Hg; for a number of these cells, the deformation response was essentially elastic and an effective membrane rigidity (EMR) was calculated. EMR increased with decreasing PO2 and was approximately 5 to 50 times higher than the equivalent rigidity of oxygenated HbSS RBC. In addition, the rate of membrane deformation was very slow for sickled cells; the half-time for the deformation process increased as PO2 was lowered and was about two orders of magnitude longer than the equivalent time for normal RBC. Other sickled cells exhibited plastic deformation when subjected to comparable deforming forces and experienced irreversible membrane deformation and budding. At all PO2 levels tested, some HbSS RBC remained as discocytes; these cells had normal membrane elasticity and membrane viscosity. Furthermore, changes in PO2 did not affect the membrane properties of HbAA RBC. Thus, gross abnormalities in the deformation response of HbSS RBC were only detected after morphological sickling had occurred. These abnormalities most likely arose from changes in the cytoplasmic HbS viscoelasticity and, if present in vivo, would be expected to impair the flow of HbSS cells in the microcirculation. 相似文献
10.
Peter A. Smith MD Ken N. Kuo MD Adam N. Graf MS Joseph Krzak PT PhD Ann Flanagan PT Sahar Hassani MS Angela K. Caudill PT Fredrick R. Dietz MD Jose Morcuende MD Gerald F. Harris PE PhD 《Clinical orthopaedics and related research》2014,472(4):1281-1290