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71.
The objective of the current study was to determine the tissue distribution of cells derived from the area opaca in heterospecific quail-chick blastodermal chimeras. Quail-chick chimeras were constructed by transferring dissociated cells from the area opaca of the stage X–XII (EG&K) quail embryo into the subgerminal cavity of the unincubated chick blastoderm. The distribution of quail cells in embryonic as well as extra-embryonic tissues of the recipient embryo were examined using the QCPN monoclonal antibody after 6 days of incubation in serial sections taken at 100-μm intervals. Data gathered in the present study demonstrated that, when introduced into the subgerminal cavity of a recipient embryo, cells of the area opaca are able to populate not only extra-embryonic structures such as the amnion and the yolk sac, but also various embryonic tissues derived from the ectoderm and less frequently the mesoderm. Ectodermal chimerism was confined mainly to the head region and was observed in tissues derived from the neural ectoderm and the surface ectoderm, including the optic cup, diencephalon and lens. Although the possibility of random incorporation of transplanted cells into these embryonic structures cannot be excluded, these results would suggest that area opaca , a peripheral ring of cells in the avian embryo destined to form the extra-embryonic ectoderm and endoderm of the yolk sac, might harbor cells that have the potential to give rise to various cell types in the recipient chick embryo, including those derived from the surface ectoderm and neural ectoderm. 相似文献
72.
Genome-wide analyses on loss of heterozygosity in head and neck squamous cell carcinomas 总被引:7,自引:0,他引:7
Beder LB Gunduz M Ouchida M Fukushima K Gunduz E Ito S Sakai A Nagai N Nishizaki K Shimizu K 《Laboratory investigation; a journal of technical methods and pathology》2003,83(1):99-105
Head and neck squamous cell carcinoma (HNSCC) is a frequent malignancy with a poor survival rate. Identifying the tumor suppressor gene (TSG) loci by genomic studies is an important step to uncover the molecular mechanisms involved in HNSCC pathogenesis. We therefore performed comprehensive analyses on loss of heterozygosity (LOH) using a genome-wide panel of 191 microsatellite markers in 22 HNSCC samples. We found 53 markers with significantly high LOH (>30%) on 21 chromosomal arms; the highest values of those were observed on 3p, 9p, 13q, 15q, and 17p, corresponding to D3S2432 (67%), D9S921-D9S925 (67%) and GATA62F03 (86%), D13S1493 (60%), D15S211 (62%), and D17S1353 (88%), respectively. Fifteen hot spots of LOH were defined in 13 chromosomal arms: 2q22-23, 4p15.2, 4q24-25, 5q31, 8p23, 9p23-24, 9q31.3, 9q34.2, 10q21, 11q21-22.3, 14q11-13, 14q22.3, 17p13, 18q11, and 19q12 as loci reported previously in HNSCCs. Furthermore, we identified five novel hot spots of LOH on three chromosomal arms in HNSCC at 2q33 (D2S1384), 2q37 (D2S125), 8q12-13 (D8S1136), 8q24 (D8S1128), and 15q21 (D15S211). In conclusion, our comprehensive allelotype analyses have unveiled and confirmed a total of 20 possible TSG loci that could be involved in the development of HNSCC. These results provide useful clues for identification of putative TSGs involved in HNSCC by fine mapping of the suspected regions and subsequent analysis for functional genes. 相似文献
73.
74.
Banu Kumbak Levent Sahin Sema Ozkan Remzi Atilgan 《Archives of gynecology and obstetrics》2014,290(2):369-374
Purpose
Endometrial biopsy preceding implantation in in vitro fertilization (IVF) treatment causes a type of injury which facilitates implantation. Pre-treatment hysteroscopic evaluation of uterine cavity also raises the success in IVF. This study investigates whether office hysteroscopy and concurrent endometrial biopsy performed in the luteal phase, on the day of GnRH agonist initiation for long protocol, improves subsequent IVF outcome.Methods
A prospective, nonrandomized, controlled study of 128 normoresponder women was performed: In 70 women (study group), office hysteroscopy and concurrent endometrial biopsy were performed on the day of GnRH agonist initiation preceding ET cycle and in 58 women (control group), GnRH agonist was initiated without any intervention. However, uterine cavity was shown to be normal with hysteroscopy within the previous 6 months in those women. Implantation and pregnancy rates were compared between the groups.Results
Intrauterine pathologies were observed in 28 % of women in the study group. Implantation rate (38 vs. 25 %; p = 0.04) and pregnancy rate per ET (67 vs. 45 %; p = 0.01) were found to be significantly higher in the study group compared to the control group.Conclusion
Office hysteroscopy and concurrent endometrial biopsy performed in the luteal phase, on the day of GnRH agonist initiation for long protocol, provide direct evaluation of the uterine cavity immediately before ET cycle and also significantly improve the implantation and IVF outcome. 相似文献75.
End-to-side venous anastomosis is sometimes necessary when there is the lack of a suitable vein, when there is a size discrepancy in the veins to be repaired, or when the anastomosis of multiple veins is required. The effects of elliptical vs. slit venotomy on vessel patency have not been investigated in a flap model. A new, simple, reliable, and reproducible model is described in which the femoral vein of the groin flap is anastomosed to the side of the deep dorsal penile vein. Elliptical hole and slit venotomies were tested in 26 Sprague-Dawley rats, and the anastomoses were 100% patent. The type of venotomy was not found to affect patency. Either technique is equally valid in end-to-side venous anastomosis, and the model itself is convenient for training. 相似文献
76.
In this article, a 9-year-old boy with arterial priapism is presented. The patient was managed with the conservative measures including imipramine hydrochloride and a favorable outcome was achieved after 2 months of follow-up. The pathophysiology, diagnostic tools and treatment alternatives are discussed. 相似文献
77.
Adanali G Erdogan B Turegun M Tuncel A Gencaga S Albayrak L 《Aesthetic plastic surgery》2002,26(5):340-344
Although there is a controversy about success and failure of autologous fat tissue transfers, it is a widely accepted method for soft tissue augmentation and is performed by many plastic surgeons as well as dermatologists all around the world. Its advantages are that it does not cause reactions, its absorption rates have been reduced by increased knowledge, experience, and techniques, it can yield good, long-term results, and there are now preservation techniques that allow reinjections when necessary. However, no single ideal technique has been determined. In this paper a new, simple, T-shaped adaptor for easy, quick, and efficient fat harvesting during liposuction is described. This study not only describes the clinical use of the adaptor, but also histologically examines its effects on fat cells under various vacuum pressures (-250 mmHg, -500 mmHg, -700 mmHg). The study shows that the cell structure of fat tissue harvested under medium power (with vacuum pressures of -250 mmHg and -500 mmHg) is not disrupted, while that of tissue harvested with a vacuum pressure of -700 mmHg was traumatized and occasional cell wall fragmentation occurred. In conclusion, it is shown that the T-shaped adaptor allows harvesting of the desired amount of fat tissue without causing trauma to fat cells when it is used with medium-power suction. 相似文献
78.
Adanali G Senen D Turegun M Tuncel A Erdogan B Albayrak L 《Aesthetic plastic surgery》2002,26(6):465-469
Androgenic alopecia is a serious problem for a large proportion of the population, especially males, and causes them to seek medical help. Many methods have been described for treatment of androgenic alopesia. Among them are punch grafts, strip grafts, scalp grafts, scalp reductions, tissue expanders, and flap combinations, and hair transplantations with minigrafts and micrografts. The latter has become popular in the last two to three decades and has been investigated extensively. Improvements in hair replacement with minigrafts and micrografts may allow an ideal result with a nearly normal appearance. However, hair replacement with these grafts has important disadvantages. It requires a long operational time and only a limited number of grafts can be placed in one session. In this study, we investigated morphological structures of micrografts stored at 4 degrees C and those stored at -20 degrees C. We found that morphological structures of the grafts stored at 4 degrees C started to be impaired in the fifth day, but that the morphological structures of the grafts stored at -20 degrees C remained unaltered for 15 days. If this method is put into practice, the use of minigrafts and micrografts available will not only obviate the second graft harvesting, but also allow reconstruction of a large area in a short period of time. 相似文献
79.
Neurofibrosarcomas are rare tumors usually arising in somatic soft tissues or peripheral nerves. Four cases of metastatic neurofibrosarcoma to the spine have been reported before. The current case is unusual because of the presence of two distinct, metachronous spinal metastasis and lung metastasis. A 30-year-old woman with neurofibromatosis and a history of previous neurofibrosarcoma resection presented with back pain. Radiologic evaluation revealed a lytic lesion of the eleventh thoracic vertebra. A transthoracal corpectomy, reconstruction by Harms' cage and posterior instrumentation, and fusion were carried out. After the completion of adjuvant chemotherapy, a solitary pulmonary nodule was detected. Shortly after resection of the metastatic pulmonary nodule, the patient complained of acute onset low-back pain. Radiologic assessment revealed another lytic lesion in the L5 vertebra after 6 months. Again, a corpectomy, anterior and posterior instrumentation, and fusion were carried out. Eight months after the second spinal resection, another solitary pulmonary metastasis was diagnosed and resected. The patient's health status suddenly deteriorated 26 months after the initial spinal metastatectomy, and she died. Though local control can be achieved in more than 80% of the patients with neurofibrosarcoma by wide surgical resection followed by adjuvant chemo- and radiotherapy, most patients die of systemic metastasis. The current patient survived 50 months after the initial resection of a forearm neurofibrosarcoma. Despite achieving local control, she died due to systemic recurrence. Prolonged survival with the help of chemo- and radiotherapy justifies our aggressive surgical strategy for the treatment of spinal metastasis in order to achieve neurologic cure and spinal stability. 相似文献