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991.
The purpose of this study is to present the importance of work-related cerebrovascular and heart disease from the viewpoint of expenses. Using the insurance benefit paid for the 4,300 cases, this study estimated the burden of insurance benefits spent on work-related cerebrovascular and heart disease. The number of cases with work-related cerebrovascular and heart disease per 100,000 insured workers were 3.36 in 1995; they were increased to 13.16 in 2000. By the days of occurrence, the estimated number of cases were 1,336 in 2001 (95% CI: 1,211-1,460 cases) and 1,769 in 2005 (CI: 1,610-1,931 cases). The estimated average insurance benefits paid per person with work-related cerebrovascular and heart disease was 75-19 million won for medical care benefit and 56 million won for other benefits except medical care. By considering the increase in insurance payment and average pay, the predicted insurance benefits for work-related cerebrovascular and heart disease was 107.9 billion won for the 2001 cohort and 192.4 billion won for the 2005 cohort. From an economic perspective, the results will be used as important evidence for the prevention and management of work-related cerebrovascular and heart disease.  相似文献   
992.
Moyamoya disease is characterized by progressive cerebrovascular occlusion at the peripheral internal carotid artery and development of abnormal collateral circulation at the cerebral basal region. Although abnormal thrombogenesis, inflammation and autoimmune process might be involved in the etiology, the genetic pathogenesis of Moyamoya disease is still unknown. To evaluate the association of Moyamoya disease with HLA alleles in the Korean population, we investigated HLA class I and class II alleles in 28 Moyamoya patients and 198 unrelated healthy controls. The frequency of HLA-B35 allele was significantly increased in the patients compared to the controls (32.1% vs. 10.1%, RR=4.2, p<0.008). Further analysis of HLA-B35 on onset age and sex showed that this allele was significantly increased compared to the controls in both late-onset and female group. Especially, HLA-B35 was the most significantly increased in female of late-onset group compared to the controls. These results suggest that HLA-B35 may be an useful genetic marker for Moyamoya disease, and particularly in females of late onset group in the Korean population.  相似文献   
993.
A total of 74 isolates of Salmonella enterica serovar London were collected through the Laboratory-Based Diarrheal Diseases Surveillance in 2000-2001. In order to characterize the isolates and investigate the source of the epidemic, we performed antimicrobial susceptibility tests and XbaI Pulsed-field gel electrophoresis (PFGE) of 44 Salmonella London isolates. Forty isolates were from feces of infants and four isolates were from adults aged 30, 52, 54, and 59 yr. Two subtypes were identified: a tetracycline-susceptible A 0 PFGE pattern and a tetracyclineresistant A 1 PFGE pattern. Interestingly, the isolates from all infants and one 30-yr-old adult were A 0 PFGE pattern and tetracycline-susceptible. Furthermore, the A 0 PFGE pattern strain was approximately 2 times more virulent than the A 1 PFGE pattern strain, according to the results of in vitro invasion assay using J774A.1 macrophage-like cells. These results indicate that the active surveillance with molecular epidemiological tools would be valuable for promptly finding new epidemic strains. Our results also suggested that the virulent Salmonella London strain might infect the infants through a common contaminated source.  相似文献   
994.
Song JJ  Lee B  Chang JW  Kim JH  Kwon YK  Lee H 《Virus research》2003,93(1):25-30
FIV-based lentiviral vector has shown a unique opportunity as an efficient gene delivery vehicle, especially to nondividing human cells. Here, we genetically reconstructed the FIV-based vector by serially deleting residual virus genes of gag and vif, leading to minimized cytotoxicity together with efficient virus production and gene transfer. The modified FIV- based vector was generated by transiently transfecting 293T cells with three plasmids of the gene transfer vector with minimal gag region, the packaging plasmid without vif and the VSV-G-expressing plasmid. The vector was routinely generated as many as 1 x 10(7) transducing particles per ml and easily concentrated by simple centrifugation. The cytotoxic effect significantly decreased in sensitive cells to FIV infection even at high multiplicity of infection (MOI), such as 500. Moreover, the transduction efficiency was consistently retained after cell cycle was arrested in a variety of human cells. Taken together, our results suggest that the modified VSV-G pseudotyped FIV-based vector efficiently transduce dividing and nondividing human cells with minimal cytotoxicity.  相似文献   
995.
Yan H  Yin FF  Guan H  Kim JH 《Medical physics》2003,30(10):2675-2685
A fuzzy logic technique was applied to optimize the weighting factors in the objective function of an inverse treatment planning system for intensity-modulated radiation therapy (IMRT). Based on this technique, the optimization of weighting factors is guided by the fuzzy rules while the intensity spectrum is optimized by a fast-monotonic-descent method. The resultant fuzzy logic guided inverse planning system is capable of finding the optimal combination of weighting factors for different anatomical structures involved in treatment planning. This system was tested using one simulated (but clinically relevant) case and one clinical case. The results indicate that the optimal balance between the target dose and the critical organ dose is achieved by a refined combination of weighting factors. With the help of fuzzy inference, the efficiency and effectiveness of inverse planning for IMRT are substantially improved.  相似文献   
996.
Peripartum hysterectomy and associated factors   总被引:4,自引:0,他引:4  
OBJECTIVE: To identify the risk factors associated with peripartum hysterectomy. STUDY DESIGN: The charts of 101 cesarean hysterectomies performed at Severance Hospital from January 1986 to April 2001 were reviewed. The patients were categorized into 2 groups. One was patients who underwent vaginal delivery followed by peripaRtum hysterectomy. The other was those who had cesarean section followed by peripartum hysterectomy. Paired t test and one-way ANOVA were used for statistical analysis. RESULTS: During the study period there were 31,044 deliveries. Peripartum hysterectomy was performed in 54 of 11,924 cesarean sections (0.45%) and 18 of 19,120 vaginal deliveries (0.09%). The most common indication for peripartum hysterectomy was uterine atony (41.58%), followed by placenta previa accreta (23.76%), placenta accreta (16.83%) and placenta previa (11.88%). Placenta previa accreta patients received the highest volume of transfusions, 1,734 +/- 688 mL (P < .05). More cesarean hysterectomies (55.93%) occurred in emergency cesarean section cases than in elective ones (44.06%). CONCLUSION: The risk factors associated with peripartum hysterectomy were placental abnormalities and previous cesarean deliveries. Hemorrhage remained the main cause of maternal mortality. Therefore, peripartum hysterectomy must be performed to save the life of the mother and must be free of dangerous sequelae.  相似文献   
997.
998.
BACKGROUND: Postmenopausal uterine inversion is an extremely rare gynecologic complication. We report a case of uterine inversion associated with endometrial polyps alone. CASE: A postmenopausal nullipara with a history of recurrent postmenopausal bleeding was evaluated for persistent vaginal bleeding. Benign endometrial polyps were found, and the patient's symptoms improved after a therapeutic dilation and curettage. She had acute onset of profuse vaginal bleeding 3 months later and a mass protruded from the cervix. A laparotomy revealed an inverted uterus that was resolved by the Haultain technique and was followed by total abdominal hysterectomy. CONCLUSION: Nonpuerperal uterine inversion associated with endometrial polyps was successfully treated surgically.  相似文献   
999.
OBJECTIVES: The objective of the study was to evaluate the effect of vitamin D receptor (VDR) gene haplotypes on bone mineral density (BMD). STUDY DESIGN: The VDR Bsm I, Apa I, Taq I, and poly(A) polymorphisms were analyzed in 417 postmenopausal Korean women. Serum 1,25(OH)(2) vitamin D(3), osteocalcin, bone alkaline phosphatase, and CrossLaps were measured by immunoradiometric assay and enzyme-linked immunosorbent assay. BMD at the lumbar spine and proximal femur was determined by dual-energy x-ray absorptiometry. RESULTS: At all skeletal sites, genotypes not carrying the baTL haplotype allele (uppercase letters signifying the absence, lowercase letters the presence, of the restriction site, and L a repeat length of more than 17) had significantly lower BMD than baTL homozygotes. The former genotypes were more prevalent in women with low bone mass than in healthy women. No significant differences in vitamin D(3) or bone markers levels were noted among the baTL haplotype genotypes. CONCLUSION: The VDR baTL haplotype allele is related to bone mass in Korean women.  相似文献   
1000.
Two classes of anatomic models currently exist for use in both radiation protection and radiation dose reconstruction: stylized mathematical models and tomographic voxel models. The former utilize 3D surface equations to represent internal organ structure and external body shape, while the latter are based on segmented CT or MR images of a single individual. While tomographic models are clearly more anthropomorphic than stylized models, a given model's characterization as being anthropometric is dependent upon the reference human to which the model is compared. In the present study, data on total body mass, standing/sitting heights and body mass index are collected and reviewed for the US population covering the time interval from 1971 to 2000. These same anthropometric parameters are then assembled for the ORNL series of stylized models, the GSF series of tomographic models (Golem, Helga, Donna, etc), the adult male Zubal tomographic model and the UF newborn tomographic model. The stylized ORNL models of the adult male and female are found to be fairly representative of present-day average US males and females, respectively, in terms of both standing and sitting heights for ages between 20 and 60-80 years. While the ORNL adult male model provides a reasonably close match to the total body mass of the average US 21-year-old male (within approximately 5%), present-day 40-year-old males have an average total body mass that is approximately 16% higher. For radiation protection purposes, the use of the larger 73.7 kg adult ORNL stylized hermaphrodite model provides a much closer representation of average present-day US females at ages ranging from 20 to 70 years. In terms of the adult tomographic models from the GSF series, only Donna (40-year-old F) closely matches her age-matched US counterpart in terms of average body mass. Regarding standing heights, the better matches to US age-correlated averages belong to Irene (32-year-old F) for the females and Golem (38-year-old M) for the males. Both Helga (27-year-old F) and Donna, however, provide good matches to average US sitting heights for adult females, while Golem and Otoko (male of unknown age) yield sitting heights that are slightly below US adult male averages. Finally, Helga is seen as the only GSF tomographic female model that yields a body mass index in line with her average US female counterpart at age 26. In terms of dose reconstruction activities, however, all current tomographic voxel models are valuable assets in attempting to cover the broad distribution of individual anthropometric parameters representative of the current US population. It is highly recommended that similar attempts to create a broad library of tomographic models be initiated in the United States and elsewhere to complement and extend the limited number of tomographic models presently available for these efforts.  相似文献   
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