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101.
Powers TA; Partain CL; Kessler RM; Freeman MW; Robertson RH; Wyatt SH; Whelan HT 《Radiology》1988,169(3):723-726
Twenty pediatric patients, aged 2-18 years, with known or suspected masses in the brain and/or spinal cord were studied with magnetic resonance imaging at 0.6T with and without use of 0.1 mmol/kg gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA). The multisection, multiecho imaging mode was utilized. Surgically proved mass lesions included astrocytoma (n = 6), medulloblastoma (n = 2), ependymoma (n = 1), craniopharyngioma (n = 1), oligodendroglioma (n = 1), germinoma (n = 1) and fibrosarcoma (n = 1). Presumptive diagnoses included astrocytoma (n = 3), arachnoid cyst (n = 1), tuberous sclerosis (n = 1), cryptic vascular malformation (n = 1), and normal (n = 1). There was dramatic enhancement in 11 of 20 patients, with improved definition of the presence and extent of lesions in six patients. No adverse effects were noted in any of the 20 patients. It is concluded that Gd-DTPA is useful in delineating the presence, extent, and number of certain lesions of the central nervous system in children. 相似文献
102.
Early gastric cancer (EGC) is defined as carcinoma in which malignant invasion is limited to the mucosa or submucosa. Records of pathologic examinations from the Hospital of the University of Pennsylvania show that EGC comprised 6% of all gastric carcinomas diagnosed between 1977 and 1983 (7/118 cases) compared with 8.2% of gastric carcinomas diagnosed between 1965 and 1977 (12/147 cases). Double contrast radiographic techniques and fiberoptic endoscopy became widely available at our institution in 1976. Thus, the application of these techniques to symptomatic patients has not improved our ability to diagnose EGC. In contrast, the incidence of EGC in Japan has risen from 5% to 35% with the widespread use of these diagnostic techniques. This discrepancy can be attributed to mass screening of asymptomatic patients in Japan because of the unusually high prevalence of gastric carcinoma in that country. American radiologists and endoscopists should therefore recognize that they are unlikely to experience a significant increase in the detection of EGC as long as these examinations are performed predominantly on symptomatic patients. 相似文献
103.
104.
We have studied the dynamics of mitochondrial DNA maintenance and
segregation in human cells using serial cybrid transfer of partially
duplicated mitochondrial DNA, from a mitochondrial myopathy patient, to two
distinct recipient cell types. The results indicate two radically different
outcomes dependent upon nuclear background. In one case (lung carcinoma)
there is systematic loss of the partial duplication by an implied
recombinational mechanism. In another nuclear background (osteosarcoma) the
duplicated molecules can survive, having only a marginal effect on
mitochondrial respiratory function. Moreover, in the osteosarcoma nuclear
background further disturbances of mtDNA maintenance frequently follow from
cybrid transfer. These are progressive, catastrophic loss of mtDNA and
further rearrangement to generate partially triplicated molecules. The
results imply differential expression of nuclear genes regulating mtDNA
copy number, replication and recombination in different human cell types.
相似文献
105.
Wynn HT PAN 《中国药理通讯》2006,23(2):4-4
National Yang-Ming University was established in 1971 at Taipei. We mainly train 7- year medical students immediately after high school education. Originally, the 4^th year students received their pharmacology teaching by an intensive course within one semester (4 hours/wk). We covered all 66 chapters in "Basic & Clinical Pharmacology", with a total 72 lecture hours. In order to design a problem-based learning course for all the courses of previous 4^th year students, our pharmacology teaching must re-organize in this integrated curriculum from the year of 2001. The major changes include: decreasing total lecture hour (from 72 to 58), one semester course becoming one-year course (roughly 2 hours/wk), merely covering 80% of all 66 chapters in the textbook. We did student survey each year and the results will be presented in our presentation. Also, the advantages and disadvantages for this reform will be discussed. 相似文献
106.
LD Rasmussen M Dybdal J Gerstoft G Kronborg CS Larsen C Pedersen G Pedersen J Jensen L Pedersen HT Sørensen N Obel 《HIV medicine》2011,12(4):202-210
Objective
The association between HIV infection and the risk of venous thromboembolism (VTE) is controversial. We examined the risk of VTE in HIV‐infected individuals compared with the general population and estimated the impact of low CD4 cell count, highly active antiretroviral therapy (HAART) and injecting drug use (IDU).Methods
We identified 4333 Danish HIV‐infected patients from the Danish HIV Cohort Study and a population‐based age‐ and gender‐matched comparison cohort of 43 330 individuals. VTE diagnoses were extracted from the Danish National Hospital Registry. Cumulative incidence curves were constructed for time to first VTE. Incidence rate ratios (IRRs) and impact of low CD4 cell count and HAART were estimated by Cox regression analyses. Analyses were stratified by IDU, adjusted for comorbidity and disaggregated by overall, provoked and unprovoked VTE.Results
The 5‐year risk of VTE was 8.0% [95% confidence interval (CI) 5.78–10.74%] in IDU HIV‐infected patients, 1.5% (95% CI 1.14–1.95%) in non‐IDU HIV‐infected patients and 0.3% (95% CI 0.29–0.41%) in the population comparison cohort. In non‐IDU HIV‐infected patients, adjusted IRRs for unprovoked and provoked VTE were 3.42 (95% CI 2.58–4.54) and 5.51 (95% CI 3.29–9.23), respectively, compared with the population comparison cohort. In IDU HIV‐infected patients, the adjusted IRRs were 12.66 (95% CI 6.03–26.59) for unprovoked VTE and 9.38 (95% CI 1.61–54.50) for provoked VTE. Low CD4 cell count had a minor impact on these risk estimates, while HAART increased the overall risk (IRR 1.93; 95% CI 1.00–3.72).Conclusion
HIV‐infected patients are at increased risk of VTE, especially in the IDU population. HAART and possibly low CD4 cell count further increase the risk. 相似文献107.
108.
BACKGROUND A wide variety of embedding techniques have been employed to process frozen sections for Mohs micrographic surgery. Prospective data comparing different techniques are lacking.
OBJECTIVE The purpose of this study was to compare tissue processing times and slide quality using the three embedding techniques.
METHODS Seventy-five consecutive Mohs surgery tissue specimens, measuring 1 cm in diameter, were prospectively randomized to processing with the CryoHist, the Cryocup, or the Miami Special. Tissue preparation times were recorded, and slide quality was evaluated. Tissue specimen preparation was standardized to exclude the use of relaxing incisions or other tissue manipulations. In a separate evaluation, slide quality was retrospectively evaluated for 50 large specimens (>2.5 cm) processed with the CryoHist machine.
RESULTS The mean tissue processing time was 11.4 minutes using the CryoHist, 12.9 minutes using the Cryocup, and 12.6 minutes using the Miami Special. Slide quality, using epidermal edge as a primary end point, was superior with the CryoHist compared to the other methods. For large (>2.5 cm) en bloc Mohs specimens processed using the CryoHist, the slide quality was excellent with 92.3% of epidermal edge obtained.
CONCLUSIONS The fully automated CryoHist embedding machine enables high-quality frozen sections to be processed in less time than the Cryocup or the Miami Special. Slide quality is excellent, even for larger specimens. 相似文献
OBJECTIVE The purpose of this study was to compare tissue processing times and slide quality using the three embedding techniques.
METHODS Seventy-five consecutive Mohs surgery tissue specimens, measuring 1 cm in diameter, were prospectively randomized to processing with the CryoHist, the Cryocup, or the Miami Special. Tissue preparation times were recorded, and slide quality was evaluated. Tissue specimen preparation was standardized to exclude the use of relaxing incisions or other tissue manipulations. In a separate evaluation, slide quality was retrospectively evaluated for 50 large specimens (>2.5 cm) processed with the CryoHist machine.
RESULTS The mean tissue processing time was 11.4 minutes using the CryoHist, 12.9 minutes using the Cryocup, and 12.6 minutes using the Miami Special. Slide quality, using epidermal edge as a primary end point, was superior with the CryoHist compared to the other methods. For large (>2.5 cm) en bloc Mohs specimens processed using the CryoHist, the slide quality was excellent with 92.3% of epidermal edge obtained.
CONCLUSIONS The fully automated CryoHist embedding machine enables high-quality frozen sections to be processed in less time than the Cryocup or the Miami Special. Slide quality is excellent, even for larger specimens. 相似文献
109.
Background
Vascular calcification is implicated in myocardial infarction, instability and rigidity of the aortic wall, and bioprosthetic failures. Although an increase in the calcium (Ca) content in atherogenic diets has been shown to decrease atherosclerosis in rabbits, whether Ca supplementation and deficiency can affect atherosclerosis-related aortic calcification remains unknown. 相似文献110.
Evidence for a novel gene for familial febrile convulsions, FEB2, linked to chromosome 19p in an extended family from the Midwest 总被引:8,自引:0,他引:8
Johnson EW; Dubovsky J; Rich SS; O'Donovan CA; Orr HT; Anderson VE; Gil-Nagel A; Ahmann P; Dokken CG; Schneider DT; Weber JL 《Human molecular genetics》1998,7(1):63-67
Febrile convulsions are a common form of childhood seizure. It is estimated
that between 2 and 5% of children will have a febrile convulsion before the
age of 5. It has long been recognized that there is a significant genetic
component for susceptibility to this type of seizure. Wallace, Berkovic and
co-workers recently reported linkage of a putative autosomal dominant
febrile convulsion gene to chromosome 8q13-21. We report here another
autosomal dominant febrile convulsion locus on chromosome 19p. Linkage
analysis in this large multi- generational family gave a maximum pairwise
lod score of 4.52 with marker Mfd120 at locus D19S177. Linkage to the
chromosome 8 locus was excluded in this family. Haplotype analysis using
both affected and unaffected family members indicates that this febrile
convulsion gene, which we call FEB2 , can be localized to an 11.7 cM, 1-2
Mb section of chromosome 19p13.3, between loci D19S591 and D19S395.
相似文献