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41.
The systems for display of foreign peptides and polypeptides on filamentous bacteriophage have exploited genetic fusion to all of the five coat proteins. Multivalent display systems allowing selection of low affinity antibody fragments have been devised for fusions to gene III. However, since pIII has to interact with the bacterial receptors during the infection process, reduced infectivity can be observed. Alternative display systems utilizing other coat protein have been examined. These, however, take advantage of phagemid systems, in which a mixture of fusion and non-fusion coat proteins becomes displayed, thus preventing multivalent display. In this paper, we describe genetically stable fusion of scFv fragments to gene VII directly in the phage genome, thus giving rise to a multivalent display system where infectivity is not comprised. A hundred-fold enrichments factor can be obtained in model selection. Our results demonstrate that the small size of pVII (33 amino acids) is not structurally compromised by fusion of scFv antibody fragments at their N-terminus, thus demonstrating the feasibility of utilizing pVII as a fusion partner. 相似文献
42.
43.
Kwaśniewska A Goździcka-Józefiak A Borzecki A Baranowski W 《European journal of gynaecological oncology》2004,25(3):359-361
The aim of the study was qualitative and quantitative evaluation of DNA adducts in squamous cell cervical carcinomas associated with oncogenic HPV infection. MATERIAL: The study material consisted of oncogenic tissue collected during the surgeries of seven women aged 37 to 52 who were undergoing surgical treatment due to squamous cell cervical carcinoma. The control group consisted of 3 tissue fragments from morphologically normal cervix collected from patients undergoing surgery due to uterine myomas. METHODS: DNA from the tissues was isolated using Genomic Prep Plus kit from A&A Biotechnology, Austria. Amplification reactions detecting HPV DNA presence in the tissue fragments were performed using specific starters allowing for amplification of conservative genome fragments within L1, E6 and E7 Papilloma viruses. After extraction, the DNA specimens underwent enzymatic digestion to nucleotides and marked on the 5' end using gamma32P-post labeling technique. Division and quantitative evaluation of DNA adducts was performed using thin-layer chromatography (TLC) on PEI-cellulose plates. Qualitative radioactivity measurements were performed using Bio-Imaging analyzer in quantitative mode. RESULTS: In all fragments, including the control, HPV 16 and/or 18 DNA was found. Mean adduct content in cervical carcinoma tissues was 289 adducts per 10(9) nucleotides and was higher than mean adduct content in control tissues (57 adducts per 10(9) nucleotides). CONCLUSIONS: The study results suggest that the content of DNA adducts in squamous cell cervical cancer associated with HPV infection may serve as a molecular marker of oncogenesis in this organ. 相似文献
44.
Lumbar discography is a diagnostic modality to determine whether the intervertebral disc is the cause of pain. The injection of radiopaque contrast into the nucleus pulposus of the disc can reveal the internal details of the disc. We describe a case of inadvertent lumbar discogram resulting from an attempted lumbar interlaminar epidural injection at L5-S1 under fluoroscopy. The patient did not have a postdural puncture headache or nerve root irritation. The potential triangle in the lateral aspect of spinal cord may be the explanation for this situation, because this triangle is composed of the exiting nerve root laterally, the lateral margin of the dura medially, and the pedicle as its base. The L5-S1 disc is located in the center of the triangle. In our case, the Tuohy needle was placed possibly in the center of the triangle, too laterally to puncture the dura. Hence, the patient did not suffer from postdural puncture headache. The needle was probably inferior to the nerve root, and no obvious nerve root trauma or irritation occurred. This potential triangle may provide alternative access for lumbar discography at the L5-S1 level. 相似文献
45.
Background
There are multiple studies in different countries regarding the prevalence of vitamin D deficiency. These studies showed high prevalence of vitamin D deficiency in Asian countries. This study tries to elucidate the prevalence of vitamin D deficiency and its influencing factors in population of Tehran.Methods
1210 subjects 20–64 years old were randomly selected. 25 (OH) D serum levels were measured. Duration of exposure to sunlight, the type of clothing and level of calcium intake and BMI were quantified based on a questionnaire.Results
A high percentage of vitamin D deficiency was defined in the study population. Prevalence of severe, moderate and mild Vitamin D deficiency was 9.5%, 57.6% and 14.2% respectively. Vitamin D serum levels had no significant statistical relation with the duration of exposure to sunlight, kind of clothing and BMI. Calcium intake in the normal vitamin D group was significantly higher than the other groups (714.67 ± 330.8 mg/day vs 503.39 ± 303.1, 577.93 ± 304.9,595.84 ± 313.6). Vitamin D serum levels in young and middle aged females were significantly lower than the older group.Conclusions
Vitamin D deficiency has a high prevalence in Tehran. In order to avoid complications of vitamin D deficiency, supplemental dietary intake seems essential. 相似文献46.
Background
Although an effective measles vaccine has been available for almost 40 years, in 2000 there were about 30 million measles infections worldwide and 777,000 measles-related deaths. The history of smallpox suggests that achieving measles eradication depends on several factors; the biological characteristics of the organism; vaccine technology; surveillance and laboratory identification; effective delivery of vaccination programmes and international commitment to eradication. 相似文献47.
Influence of physiologic 17 beta-estradiol concentrations on gene E6 expression in HVP type 18 in vitro 总被引:1,自引:0,他引:1
Many recent studies indicate that long term use of contraceptives is a strong risk factor in the development of cervical cancer. Steroid hormones, in persistent papilloma virus infection act on various levels, one of them is enhancing transforming activity of the virus. The aim of the study was to estimate if physiological concentrations of 17 beta-estradiol could influence expression of viral transforming genes. HeLa cell lines were incubated with three different physiological concentrations and and on the third day of incubation the level of E6 gene expression was determined. Results show no differences in expression between the control culter, and cultures incubated with physiological concentrations. It indicates that normal levels of 17 beta-estradiol don't play role in transforming process but it also shows need to analyse higher levels of hormones by quantitative analyses in prospective studies. 相似文献
48.
van der Maten J Blaauwgeers JL Sutedja TG Kwa HB Postmus PE Wagenaar SS 《The Journal of thoracic and cardiovascular surgery》2003,126(3):740-743
OBJECTIVE: To describe the population-based incidence and clinical characteristics of granular cell tumors of the tracheobronchial tree. METHODS: All newly registered tracheobronchial granular cell tumors in the Dutch Network and National Database for Pathology for 10 consecutive years (1990-1999) were identified. The histologic diagnosis was confirmed and patient demographics, management, and follow-up data were analyzed. RESULTS: Thirty-one tumors were registered in 30 patients (12 male patients and 18 female patients; mean age 51 years; range 11-84) in a population of approximately 15 million. Tracheal tumors were identified in 11 patients and bronchial tumors in 19 patients (1 patient had 2 tumors). About half of the patients were asymptomatic. In the majority of the patients (61%) the granular cell tumor was an incidental finding during workup for lung carcinoma. Tracheal granular cell tumors were more frequent in women, whereas bronchial granular cell tumors showed no sex predilection. In the lung these tumors occurred more often in the upper (10 tumors) than in the lower lobes (3 tumors). There was no preference for either side. Four patients with tracheal and 4 with bronchial granular cell tumors were treated with surgery and remain in complete remission. Four bronchial granular cell tumor patients were treated locally with neodymium/yttrium-aluminum-garnet laser or electrocautery and are in complete remission or have stable residual disease. In 3 patients no residual disease was found after biopsy. Of all granular cell tumor patients 17 received no treatment for a variety of reasons, but none of these patients died in the follow-up period because of the granular cell tumors. CONCLUSION: Tracheobronchial granular cell tumor is a benign tumor with a good prognosis. In symptomatic patients surgical intervention is the first choice of treatment, but local treatment is a reasonable option and gives successful results. 相似文献
49.
Thiamine, riboflavin, pyridoxine, and vitamin C status in premature infants receiving parenteral and enteral nutrition 总被引:1,自引:0,他引:1
Friel JK Bessie JC Belkhode SL Edgecombe C Steele-Rodway M Downton G Kwa PG Aziz K 《Journal of pediatric gastroenterology and nutrition》2001,33(1):64-69
BACKGROUND: There is a paucity of data about water soluble vitamin status in low birthweight infants. Therefore, the authors' objective was to assess current feeding protocols. METHODS: The authors measured serum concentrations for riboflavin, pyridoxine, and vitamin C and functional assays for thiamine and riboflavin longitudinally in 16 premature infants (birthweight, 1,336 +/- 351 g; gestational age, 30 +/- 2.5 weeks) before receiving nutrition (time 1, 2 +/- 1 days), during supplemental or parenteral nutrition (time 2, 16 +/- 10 days) and while receiving full oral feedings (time 3, 32 +/- 15 days). In plasma, vitamin C was measured colorimetrically, and riboflavin and pyridoxine were measured using high-performance liquid chromatography. The erythrocyte transketolase test as a functional evaluation of thiamine and the erythrocyte glutathione reductase test for riboflavin were measured colorimetrically. RESULTS: At time 1, nutrient intake of vitamins were negligible because infants were receiving intravenous glucose and electrolytes only. Intakes differed between time 2 and time 3 for thiamine (510 +/- 280 and 254 +/- 115 microg. kg-1. d-1, respectively), riboflavin (624 +/- 305 and 371 +/- 193 microg. kg-1. d-1, respectively), and pyridoxine (394 +/- 243 and 173 +/- 85 microg/100 kcal, respectively), but not for vitamin C (32 +/- 17 and 28 +/- 12 mg. kg-1. d-1, respectively). Blood levels at times 1, 2, and 3 were for thiamine (4.9 +/- 2.7%, 3.3 +/- 6.6%, and 4.1 +/- 9% erythrocyte transketolase test, respectively), riboflavin (0.91 +/- 0.31, 0.7 +/- 0.3, 0.91 +/- 0.18 erythrocyte glutathione reductase test, respectively), riboflavin (19.5 +/- 17, 23.3 +/- 8.6, 17.6 +/- 10 ng/mL, respectively), pyridoxine (32 +/- 25, 40 +/- 16, 37 +/- 26 ng/mL, respectively), and vitamin C (5.2 +/- 3, 5 +/- 2.2, 10 +/- 5 microg/mL, respectively) and did not differ at those times. CONCLUSIONS: Current intakes of these vitamins, except for possibly vitamin C, during parenteral and enteral nutrition seem to result in adequate plasma concentrations and normal functional indices. 相似文献
50.