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11.
Use of a curved-array transducer to reduce interobserver variation in sonographic measurement of thyroid volume in healthy adults 总被引:1,自引:0,他引:1
Peeters EY Shabana WM Verbeek PA Osteaux MM 《Journal of clinical ultrasound : JCU》2003,31(4):189-193
PURPOSE: Sonographic calculation of thyroid volume is used in the diagnosis and follow-up of thyroid diseases. Since the calculated volume of thyroid lobes is highly influenced by the longest (ie, craniocaudal) diameter, we examined whether using a curved-array transducer as opposed to a linear-array transducer to measure the craniocaudal diameter would reduce interobserver variation. METHODS: Three sonographers with different levels of expertise each used a 5-12-MHz linear-array transducer and a 2-5-MHz curved-array transducer to measure the craniocaudal diameter of both thyroid lobes of 25 healthy volunteers. On the basis of these measurements, thyroid lobe volumes were calculated. Single-factor analysis of variance was used to evaluate the interobserver variations between the measurements made by all 3 observers as well as between measurements taken by pairs of observers. A p value of less than 0.05 was considered significant. RESULTS: Using the linear-array transducer to measure the craniocaudal diameter resulted in significant interobserver variation in thyroid volume calculation (p = 0.02), whereas using the convex-array transducer did not. Using either transducer resulted in a highly significant interobserver variation in measurements of the craniocaudal diameter, although the variation was far more pronounced for measurements made with the linear-array transducer (p = 0.0005) than for those made with the curved-array transducer (p = 0.04). For both transducers, the interobserver variations were most pronounced between the most and the least experienced sonographers. CONCLUSIONS: To avoid significant interobserver variation in calculating thyroid lobe volume, we recommend using a curved-array transducer to measure the craniocaudal diameter of the thyroid lobes. 相似文献
12.
Association Patterns of Endothelial Nitric Oxide Synthase Gene (NOS3) Variant Glu298Asp with Blood Pressure and Serum Lipid Levels in Subjects with Coronary Artery Disease from Pakistan 下载免费PDF全文
Nitric oxide is an important antiatherosclerotic agent. The main determinant of nitric oxide levels is enzyme nitric oxide synthase encoded by the NOS3 gene, the common variants in this gene may be responsible for variations in plasma enzyme levels. The association of NOS3 variants with coronary artery disease (CAD) varies in different ethnicities. The current study aimed to determine the association of NOS3 Glu298Asp (rs1799983) with CAD and blood lipid levels in Pakistani subjects. Six hundred thirty‐six samples (412 cases, 224 controls) were genotyped by TaqMan allelic discrimination assay and serum total cholesterol, and High Density Lipoprotein cholesterol (HDL‐C)/Low Density Lipoprotein cholesterol (LDL‐C) and triglycerides were measured. The genotype frequency was Glu/Glu = 64.6%, Glu/Asp = 30.1%, and Asp/Asp = 5.3% in cases, and Glu/Glu = 68.8%, Glu/Asp = 26.7%, and Asp/Asp = 4.5% in controls. The Asp298 (T) frequency was not significantly higher in cases than controls (20.4% vs 17.9%, P = 0.28) and risk allele was not associated with CAD (OR 1.15 (0.86–1.54), P = 0.33) and the tested lipid traits but had a strong association with blood pressure (for systolic and diastolic P = 1.9×10?–56 and 4×10?–40, respectively). In conclusion, although Glu298Asp did not show association with CAD and lipid profile in the studied cohort, it may exert its effect through blood pressure; however, the mechanism of this effect needs to be explored in the future. 相似文献
13.
Anum Gul Bimal Kunwar Maryam Mazhar Kahkashan Perveen Shabana U. Simjee 《Inflammation》2017,40(4):1177-1190
RANKL and RANK are potential contributors of inflammatory cascade in human and animal model of arthritis. The current study aims to investigate the effect of N-(2-hydroxyphenyl)acetamide (NA-2) on regulation of RANKL pathway in collagen-induced arthritis (CIA) model in rats. CIA was induced using bovine type II collagen in female Wistar rats. The clinical parameters, level of pro-inflammatory and oxidative stress markers were measured to determine the progression of the disease. The mRNA level of RANKL and RANK and downstream mediators of inflammation i.e. c-fos, c-jun, NF-κB and Akt were analysed in spleen tissue using real-time PCR. Immunohistochemical analysis of iNOS, pAkt and c-Fos was also done in spleen tissue. Treatment with NA-2 and indomethacin showed increase in body weight and significant reduction in paw volume and arthritic score (p < 0.0001). Marked reduction in the level of oxidative stress markers, NO, PO and GSH (p < 0.0001), and pro-inflammatory markers, IL-1β (p < 0.0001) and TNF-α (p < 0.01), was also observed. Likewise, NA-2 and indomethacin treatment also significantly suppressed the mRNA expression of RANKL, RANK, c-fos, c-jun, NF-κB (p < 0.0001) and Akt (p < 0.01) and protein expression of iNOS, pAkt and c-Fos (p < 0.0001) compared to the arthritic control group. Our findings suggest that NA-2 is an antiarthritic agent acting in a pleiotropic manner in CIA rats by not only reducing the clinical signs of arthritis, inflammatory cytokines and free radical production but also attenuating the RANK/RANKL signaling pathway. 相似文献
14.
The diagnostic effectiveness of an initial transvaginal scan in detecting ectopic pregnancy 总被引:7,自引:0,他引:7
Kirk E Papageorghiou AT Condous G Tan L Bora S Bourne T 《Human reproduction (Oxford, England)》2007,22(11):2824-2828
BACKGROUND: To determine the effectiveness of an initial transvaginal ultrasound scan (TVS) in the detection of ectopic pregnancy in consecutive women attending an early pregnancy unit (EPU). METHODS: This was a prospective observational study. Unselected women attending a dedicated EPU underwent a TVS. Women were classified as having an intrauterine pregnancy (IUP), ectopic pregnancy or pregnancy of unknown location (PUL). Women with a PUL were followed up until the final location of the pregnancy was determined. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) with 95% confidence intervals (CIs) for the initial TVS in the diagnosis of ectopic pregnancy were calculated. RESULTS: During a one-year study period, 5318 consecutive women attended the EPU. Outcome data were available for 5240 (98.5%) women. Of these, the initial TVS showed an IUP in 4693 (89.6%) cases and an ectopic pregnancy in 91 (1.7%) cases. The remaining 456 (8.7%) women were classified as PUL, and of these 31 (6.8%) were subsequently found to have ectopic pregnancies. The overall sensitivity of the initial TVS in the diagnosis of ectopic pregnancy was 73.9% (95% CI: 65.1-81.6) with a specificity of 99.9% (95% CI: 99.8-100), a PPV of 96.7% (95% CI: 90.7-99.3) and an NPV of 99.4% (95% CI: 99.2-99.6). CONCLUSIONS: In unselected women attending an EPU, pregnancy location can be diagnosed accurately in over 90% of all pregnancies and in 73.9% of ectopic pregnancies with a single TVS. 相似文献
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17.
Two hundred ears with otosclerosis have been operated upon using a 0.4-mm diameter Teflon platinum piston in 100 ears and a 0.6-mm diameter Teflon piston in the other 100 ears. The postoperative air-bone gap, calculated as the difference between the postoperative air and bone conduction levels, was smaller in the 0.6 mm group for all frequencies except at 2000 Hz, the differences were statistically insignificant except at 4000 Hz. The mean postoperative air-bone gap was 8.6 dB and 7.4 dB for the 0.4 and 0.6 mm groups, respectively, which is statistically insignificant. We found no postoperative loss of bone conduction exceeding 15 dB, there was a deterioration of more than 10 dB in three ears, one in the 0.4 mm group and two in the 0.6 mm group. According to our results, we conclude that the 0.4 mm and the 0.6 mm Teflon prostheses produce the same hearing improvement in stapes surgery for otosclerosis. 相似文献
18.
Shabana Ather Katherine D Chung Patrice Gregory Kitaw Demissie 《The Journal of asthma》2004,41(7):709-713
CONTEXT: Asthma is ranked as the ninth most common chronic condition in the U.S., and its annual direct costs from hospital services alone are estimated at $3.1 billion. Hospitalization rates due to asthma reveal several disparities and may be attributed to recent changes in the healthcare delivery system, including the penetration of managed care. OBJECTIVE: To examine the relationship between 7-day hospital readmission and insurance provider among adults with asthma. DDESIGN: A retrospective cohort study that included patients aged 18-64 with a principal diagnosis of asthma, who were discharged from acute nonfederal hospitals in New Jersey between 1 January 1993 and 31 December 1996. In the absence of unique patient identifiers, a linkage system was used to match subsequent readmissions for the same patient to the first admission. MMAIN OUTCOME MEASURE: Seven-day readmission. RESULTS: Results showed a significantly increased risk of 7-day readmission for managed care patients as compared to indemnity patients (OR= 1.67, 1.10-2.53). Shorter lengths of stay were associated with greater odds of readmission (LOS=0: OR=5.17, 2.49-10.75, LOS=1: OR=2.30, 1.30-4.07). CONCLUSIONS: Managed care patients have shorter lengths of stay as compared to indemnity patients, which leads to an increased risk of returning to the hospital within a short period of time. In trying to provide cost-effective patient care, we may be discharging patients prematurely. 相似文献
19.
OBJECTIVE: To examine the effect of change in velocity (MV) and energy dissipation (IE) on impact, above and below the test levels for federal motor vehicle crash (MVC) safety standards, on the incidence of aortic injury (AI) and its mortality and associated injury patterns in frontal (F) and lateral (L) MVCs. Comparison of 80 AI and 796 non-AI patients of AIS=3. METHODS: Eight hundred seventy-six MVC adult drivers or front-seat passengers (552 F and 324 L) evaluated by 10 Level I CIREN study Trauma Centers together with vehicle and crash scene engineering reconstruction. Patient seatbelt and/or airbag use correlated with clinical or autopsy findings. RESULTS: In AI, 63% of cases were dead at the scene and only 16% survived to leave hospital. The relation between IE dissipated in the MVC and the DeltaV on impact was exponential as DeltaV increased, but the rise in IE for a given DeltaV was greater in LMVC than in FMVC (p <0.05). A more rapid rise in IE/DeltaV occurred above the mean DeltaV of 48 +/- 19.7 kph (30 mph) in FMVC and above the mean DeltaV of 36 +/- 16.2 kph (23 mph) in LMVC. As DeltaV increased above these means, 65% of 46 FMVC aortic injuries (AIs) and 64% of 34 LMVC AIs occurred. In AI patients there was evidence of focusing of the point of IE impact on the upper chest with a higher incidence of rib1-4 fractures than in non-AI (p <0.01) and more brain, heart, lung and spleen injuries (p <0.01) consequent to lower seatbelt use (p <0.01), but LMVC also had more pelvic fx (p <0.05). Airbags + seatbelts in FMVC and seatbelts in LMVC reduced mortality (p <0.05) Comparison of AI incidence in three successive 4-year vehicle model year periods showed a progressive decrease as new safety devices were introduced (p < 0.05). CONCLUSIONS: The implications for AI of the focused IE at the upper chest suggest a probable mechanism for MVC AI with the pressurized aortic arch acting as the long arm of a lever system with the fulcrum at the subclavian artery, producing maximum torsional strain at the short arm of the isthmus where 75% of the AIs occurred. AI mortality is also influenced by the associated injuries. To develop more effective safety systems to prevent AI, MVC safety testing with airbags and seatbelts should be carried out at DeltaVs of 1 SD above means for FMVC and LMVC. 相似文献
20.
Shabana W De Maeseneer M Machiels F De Ridder F Osteaux M 《European journal of radiology》2003,47(1):10-15
PURPOSE: To determine whether half-Fourier MR image acquisition technique can provide similar information to that of conventional MR acquisition technique for evaluation of meniscal tears. MATERIALS AND METHODS: We studied 101 menisci in 52 patients who were referred for evaluation of meniscal tears. Sagittal MR images of the knee were obtained for all patients by using proton density and T2-weighted SE sequences on a 1-T clinical system. The half-Fourier technique and conventional technique were used for all patients. All other imaging parameters were identical for both sequences (TR/TE=2400/20,70; 3 mm slice thickness; 200 x 256 matrix; field of view, 200; one signal acquired). Both sets of images were filmed with standard window and level settings. Images were randomised and interpreted independently by two radiologists for the presence of meniscal tears. Images were also subjectively assessed for image quality using a five-point grading scale. RESULTS: On half-Fourier images, Reader 1 interpreted 23 menisci as torn, compared to 28 for Reader 2. On conventional images, Reader 1 interpreted 24 menisci as torn, compared to 26 for Reader 2. Agreement between interpretation of the conventional and that of the half-Fourier images was 99% for Reader 1, and 98% for Reader 2. Agreement between readers for the half-Fourier images was 95%, and for the conventional images 96%. No statistically significant difference was found in the subjective evaluation of image quality between the conventional and half-Fourier images. CONCLUSION: The half-Fourier acquisition technique compares favourably with the conventional technique for the evaluation of meniscal tears. 相似文献