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531.

Objectives:

This study investigated the radio-opacity of commercially available glass ionomer cements (GICs), flowable resin composites (FRCs) and calcium hydroxide cements (CHCs) and compared this with the radio-opacity of enamel, dentine and aluminium stepwedge. 16 GICs, 8 FRCs and 4 CHCs were analysed.

Methods:

Three sets of three samples were prepared: 1 mm, 2 mm and 3 mm thickness for GIC and FRC and 1 mm thickness for CHC. Specimens of enamel and dentine with the same thicknesses were obtained. As a control, an aluminium stepwedge was used. Radiographs were taken with a digital Kodak RVG 5000 (0.32 s, 30 cm). The images were analysed using the Image Tool® program (v. 2.00; The University of Texas Health Science Center, San Antonio, TV) to obtain the mean grey values.

Results:

Analysis of variance was used to investigate the significance of differences among the groups. For pairwise comparisons, the Tukey test was applied (p < 0.05). The GICs Ionomaster (Wilcos, Petrópolis, Brazil), Maxxion (FGM, Joinville, Brazil), Bioglass R (Biodinâmica, Ibiporã, Brazil), Bioglass F (Biodinâmica), Vidrion R (SS White, Rio de Janerio, Brazil) and Vidrion F (SS White), presented radio-opacity lower than that of dentine. All FRCs and CHCs studied showed radio-opacity higher than that of dentine. Vitro Fil (DFL, Rio de Janeiro, Brazil), Magic Glass (Vigodent, Rio de Janeiro, Brazil), Vitrebond (3M, Sumaré SP, Brazil), Riva Self Cure (SDI, Victoria, Australia), Riva Light Cure (SDI), Fill Magic (Vigodent), Opallis (FGM, Joinville, Brazil), Surefil SDR (Dentsply, Milford, DE), Tetric N (Ivoclar Vivadent, Schaan, Lichtenstein), Tetric (Ivoclar Vivadent), Hydro C (Dentsply, Petrópolis, Brazil), Hydcal (Technew, Madalena, Portugal) and Liner (Vigodent) showed radio-opacity similar to or greater than that of enamel for all thicknesses.

Conclusions:

The increased thickness of the materials studied increases their radio-opacity. Some commercially available GICs used as a base and liner for restorations have a very low radio-opacity (Ionomaster, Maxxion, Bioglass R, Bioglass F, Vidrion R and Vidrion F).  相似文献   
532.
SUMMARY The aim of this pilot study was to evaluate the efficacy and safety of lansoprazole plus clarithromycin for eradication of Helicobacter pylori. A total of 26 patients with H. pylori infection were randomised to receive clarithromycin, 500 mg t.i.d. for 14 days, plus either lansoprazole, 30 mg o.m., (group L30, n=13) or lansoprazole, 30 mg b.i.d., (group L60, n=13). H. pylori status was determined pre-treatment and four to six weeks after completion of the study medication by histology and 13C-urea breath test. Two patients were unable to complete the course of medication. Of the remaining 24 patients, 14 (58%) successfully eradicated H. pylori — 8/12 (67%) patients in group L30 and 6/12 (50%) in group L60. Side-effects were experienced by 17/26 (65%) of patients, most commonly a taste disturbance. The results from this pilot study suggest that dual therapy with lansoprazole plus clarithromycin is only a moderately effective regimen for eradicating H. pylori.  相似文献   
533.
The composition of pigment gallstones from patients with and without cirrhosis was compared. Carbonate-containing pigment stones were distinguished from noncarbonate stones by infrared spectroscopy. Calcium was the major cation of each stone group. The major anion in noncarbonate pigment stones was bilirubinate or phosphate, but was carbonate in carbonate stones. The composition of pigment stones from cirrhotic and noncirrhotic patients was similar except that significantly less carbonate was present in carbonate stones, and less pigment (bilirubinate) was present in noncarbonate stones from noncirrhotics. These data suggest that irrespective of the presence of cirrhosis, the formation of noncarbonate pigment stones involves the selective precipitation of calcium bilirubinate and phosphate, whereas carbonate stone formation involves the selective precipitation of calcium carbonate.  相似文献   
534.
535.

Background

Primary Cytomegalovirus (CMV) infection during pregnancy is a frequent and serious threat to the fetus. As there is no vaccine alternative measures are needed to prevent congenital CMV infection.

Objective

This study determined CMV Immunoglobulin G (IgG) antibody among pregnant women in order to ascertain the immune status of mothers to guide policy makers.

Methods

A semi-structured questionnaire was initially administered to obtain information on demographic details, stage of pregnancy and risk factors. Blood was collected by venipuncture from 180 women attending the antenatal clinic in Murtala Mohammed Specialist Hospital Kano, Kano State, Nigeria. Sera samples were screened using CMV IgG ELISA kit (Dialab, Austria).

Results

Out of 180 pregnant women, 164 (91.1%) were seropositive. Based on stages of pregnancy 6/6(100%), 52/60(86.7%) and 106/114(93.0%) were seropositive among women in the first, second and third trimesters respectively.

Conclusion

Seroprevalence of pregnant women to CMV Ig G is high, hence the need for CMV - IgM screening to know the extent of active infection. There is also need for public enlightenment on the methods of transmission, effective prevention and control strategies.  相似文献   
536.
537.
Summary A diabetic patient with severe diabetic nephropathy and cirrhosis developed medically intractable ascites. A peritoneovenous shunt was inserted and a 4.7-kg diuresis followed, with improvement in ascites, renal function, and ambulatory ability. Prior to shunt placement, Swan-Ganz pulmonary artery catheterization provided useful assessment of cardiac and renal response to acute volume challenge. Primary renal disease is not an absolute contraindication to peritoneovenous shunt placement.Dr. Gregory is the recipient of an academic career-development award (AM70318) from the National Institutes of Health.  相似文献   
538.
We studied the role of ultrasound assessment of the thyroid gland in detecting amyloid deposition in 9 patients confirmed to have renal amyloidosis because the thyroid gland is a readily accessible organ. Ultrasound examination of the thyroid gland showed a distinctive abnormal appearance in 7 patients. There was enlargement of one or both lobes of the thyroid, a high echogenicity approaching that of the surrounding connective tissue, and a very fine homogeneous echotexture similar to ground glass appearance. Four patients showed dilated follicles in the thyroid gland. The other two patients had normal ultrasound findings. Open wedge biopsy of the thyroid gland in 4 patients, (3 with abnormal ultrasound findings and 1 with normal ultrasound findings) showed amyloid deposits in the 3 patients with abnormal echo findings and no amyloid deposits in the 1 patient with normal findings. In 10 healthy individuals, 10 patients who were just initiated on maintenance hemodialysis and another 10 patients on dialysis for more than 1 year, the thyroid gland was of normal size and appearance in the ultrasound examination. We conclude that ultrasound examination by an experienced radiologist is a useful tool in the diagnosis of thyroid amyloidosis. © 1994 John Wiley & Sons, Inc.  相似文献   
539.

Background  

Treatment efficacy of physical agents in osteoarthritis of the knee (OAK) pain has been largely unknown, and this systematic review was aimed at assessing their short-term efficacies for pain relief.  相似文献   
540.
Background  Kaposi sarcoma (KS), a malignancy of dermal endothelial cells that is caused by human herpesvirus 8 (HHV8) infection, is sensitive to perturbations of immunity. Nicotine might be effective against KS because of its immunologic and vascular effects and because smoking is associated with a low risk of KS.
Objective and study design  We conducted a masked, randomized phase 2 clinical trial of transdermal nicotine and placebo patches to assess the safety and efficacy of nicotine against classic KS (cKS).
Subjects and methods  Three cKS lesions, predominantly nodules, in each of 24 non-smoking patients were randomly assigned to 15 weeks continuous treatment with nicotine patch (escalated to 7 mg), identical masked placebo patch or no patch. Changes in lesion area and elevation from baseline through six follow-up visits, by direct measurement and by two independent readers using digital photographs of the lesions, were compared using non-parametric and regression methods. Changes in longitudinal levels of HHV8 antibodies and DNA in blood cells were similarly assessed.
Results  There were no systemic or serious adverse events, and compliance was good. One patient resumed smoking and discontinued patches, and two patients withdrew at week 12 for unrelated indications. Six (29%) of the remaining 21 suspended use of patches to relieve local skin irritation; four of these six completed the trial at reduced dose. Treatment assignment was not associated with significant or consistent changes in cKS lesion area or elevation, HHV8 viral load or antibodies.
Conclusion  Transdermal nicotine and placebo patches caused no serious toxicities but had no demonstrable effect on nodular cKS lesions or HHV8 levels.  相似文献   
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