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71.
72.
Sonographic breast imaging has been useful in the differentiation of cystic from solid masses. It has also been helpful in the characterization of palpable breast masses in the absence of corresponding abnormalities. The authors undertook a prospective study that incorporated pulsed Doppler analysis into sonographic real-time imaging of solid breast masses. Thirty-eight patients were examined. In 12 of the patients there were positive Doppler signals, while in 26 patients there were no Doppler signals. The 12 patients showing positive Doppler signals proved to have infiltrating ductal carcinoma, while the 26 patients with negative Doppler signals proved to have benign breast disorders. Pulsed Doppler analysis as a supplement to sonographic real-time imaging shows promise for the identification of breast carcinoma. 相似文献
73.
Turner DA; Alcorn FS; Shorey WD; Stelling CB; Mategrano VC; Merten CW; Silver B; Economou SG; Straus AK; Witt TR 《Radiology》1988,168(1):49-58
Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer. 相似文献
74.
The epidemic of the acquired immunodeficiency syndrome (AIDS) has affected all geographic regions of the United States. Indeed, it is likely that a majority of U.S. hospitals have cared for patients who are infected with the human immunodeficiency virus (HIV), the virus that causes AIDS. More than 46,000 individuals with HIV infection have fulfilled the strict diagnostic criteria for AIDS (1). All of these patients with AIDS have been seriously ill and have been hospitalized, often multiple times and for prolonged periods. Another, larger group patients with HIV infection has had another form of the disease, the so-called AIDS-related complex. Many of these patients have also spent time in hospitals. An even larger group of individuals has been infected with HIV but has remained asymptomatic to date. Some of these persons have been admitted to hospitals or have received outpatient diagnostic procedures for intercurrent medical or dental complaints that were unrelated to their asymptomatic HIV infection. At the time of their medical evaluation, some of these asymptomatic individuals were known to have a positive HIV antibody test. It is likely, however, that the serologic status of the majority of asymptomatically infected patients was unknown. Thus, by now a very large number of health-care personnel in the United States, including diagnostic radiology staff, have assisted in the care of HIV-infected patients. 相似文献
75.
The Radiation Oncology Center in Sacramento, California, has developed a procedure for establishing an intraoperative radiation therapy facility in a community practice. The logistics pertaining to personnel, equipment, physical measurements, and quality assurance are presented. Particular emphasis is given to the most effective means of acquiring the large quantity of data needed to ensure a program of acceptable quality. 相似文献
76.
77.
Lalit?DandonaEmail author Pratap?Sisodia SG?Prem?Kumar YK?Ramesh A?Anod?Kumar M?Chalapathi?Rao Elliot?Marseille M?Someshwar Nell?Marshall James?G?Kahn 《BMC public health》2005,5(1):98
Background
Female sex workers and their clients play a prominent role in the HIV epidemic in India. Systematic data on the outputs, cost and efficiency for HIV prevention programmes for female sex workers in India are not readily available to understand programme functioning and guide efficient use of resources. 相似文献78.
Elisa?Lloyd-Smith Thomas?Kerr Robert?S?Hogg Kathy?Li Julio?SG?Montaner Evan?WoodEmail author 《Harm reduction journal》2005,2(1):24
Recent studies have indicated that injection-related infections such as abscesses and cellulitis account for the majority
of emergency room visits and acute hospitalizations accrued by local injection drug users. The objective of this analysis
was to examine the prevalence and correlates of developing an abscess among a cohort of injection drug users in Vancouver
and to identify socio-demographic and drug use variables associated with abscesses at baseline. We examined abscesses among
participants enrolled in a prospective cohort of injection drug users. Categorical variables were analyzed using the Pearson's
chi-square test and continuous variables were analyzed using the Wilcoxon signed rank test. Among 1 585 baseline participants,
341 (21.5%) reported having an abscess in the last six months. In a logistic regression model that adjusted for all variables
that were associated with having an abscess at p < 0.1 in univariate analyses, female gender [odds ratio (OR) = 1.7, [95%CI:
1.2 – 2.4]; p = 0.002), recent incarceration (OR = 1.7, [95%CI: 1.3 – 2.2]; p < 0.001), sex trade involvement (OR = 1.4 [95%
CI: 1.0 – 2.0]; p = 0.03), frequent cocaine use (OR = 1.5 [95%CI: 1.2 – 2.0]; p = 0.002) and HIV serostatus (OR = 1.5, [95%CI:
1.2 – 2.0]; p = 0.003) were positively associated with having an abscess. Explanations for these associations require further
study, and interventions are needed to address this highly prevalent concern. 相似文献
79.