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21.
The frequency of reversible and irreversible visual impairment was determined in children with severe and profound sensorineural deafness, as subnormal vision can adversely affect their educational and social development. Eighty three of 87 such children attending an audiology service were examined to assess the incidence and severity of visual impairment. Each child underwent a detailed ophthalmic assessment. The criteria for visual impairment were visual acuity < 6/9 Snellen or equivalent and/or abnormal binocular vision. Forty five had a normal ophthalmic examination (54.2%). Twenty nine had visual impairment (34.9%) and nine had ophthalmological abnormalities that did not interfere with vision (10.9%). A higher proportion of children with risk factors for visual pathology demonstrated visual impairment than those in whom there were no risk factors. None the less, 44% of visual impairment was among patients without risk factors. The results underline the need to examine all children with severe and profound sensorineural deafness soon after diagnosis and indicate that children with multiple handicaps have a greater likelihood of visual impairment (11 of 14 cases). 相似文献
22.
Gudny Eiriksdottir Asgeir Sigurdsson Jon Gunnlaugur Jonasson Bjarni A. Agnarsson Helgi Sigurdsson Julius Gudmundsson Jon Thor Bergthorsson Rosa Bjrk Barkardottir Valgardur Egilsson Sigurdur Ingvarsson 《International journal of cancer. Journal international du cancer》1995,64(6):378-382
Primary breast tumors were tested for loss of heterozygosity (LOH), on chromosome 9p with microsatellite markers restricted to a 28 cM region including the MTS1 gene. LOH was found with at least I marker in 38% of the 201 cases analyzed. A high frequency of deletions was detected at the 9p23-p21 region, indicating a tumor suppressor gene(s) important for breast cancer tumorigenesis. Tumors with and without LOH on 9p were compared with respect to clinico-pathological factors using X2 analysis. Tumors with 9p LOH were significantly associated with high S-phase status and aneuploidy, but not with type, node status, estrogen and progesterone receptor content or age of the patients at diagnosis. Survival analysis showed that LOH at 9p did not significantly affect the survival rate of breast cancer patients. Our results indicate that the aberrations on 9p detected in this study are not of independent prognostic value. A significant association was found between LOH at 9p and LOH at chromosomal arms 3p and 6q, which is an additional contribution toward understanding the genetic events in breast tumor pathogenesis. © 1995 Wiley-Liss, Inc. 相似文献
23.
Ingvarsson S Sigbjornsdottir BI Huiping C Hafsteinsdottir SH Ragnarsson G Barkardottir RB Arason A Egilsson V Bergthorsson JT 《Breast cancer research : BCR》2002,4(3):R4-6
Background
Mutations in the CHK2 gene at chromosome 22q12.1 have been reported in families with Li-Fraumeni syndrome. Chk2 is an effector kinase that is activated in response to DNA damage and is involved in cell-cycle pathways and p53 pathways.Methods
We screened 139 breast tumors for loss of heterozygosity at chromosome 22q, using seven microsatellite markers, and screened 119 breast tumors with single-strand conformation polymorphism and DNA sequencing for mutations in the CHK2 gene.Results
Seventy-four of 139 sporadic breast tumors (53%) show loss of heterozygosity with at least one marker. These samples and 45 tumors from individuals carrying the BRCA2 999del5 mutation were screened for mutations in the CHK2 gene. In addition to putative polymorphic regions in short mononucleotide repeats in a non-coding exon and intron 2, a germ line variant (T59K) in the first coding exon was detected. On screening 1172 cancer patients for the T59K sequence variant, it was detected in a total of four breast-cancer patients, two colon-cancer patients, one stomach-cancer patient and one ovary-cancer patient, but not in 452 healthy individuals. A tumor-specific 5' splice site mutation at site +3 in intron 8 (TTgt [a → c]atg) was also detected.Conclusion
We conclude that somatic CHK2 mutations are rare in breast cancer, but our results suggest a tumor suppressor function for CHK2 in a small proportion of breast tumors. Furthermore, our results suggest that the T59K CHK2 sequence variant is a low-penetrance allele with respect to tumor growth. 相似文献24.
目的使用非线性成长率理论分析人眼视力发展规律。方法使用高斯光学及成像方程推导出两个参数:屈光状态改变率(M)及眼轴成长率(N),用以预测MOS(初始近视)、年龄(A^*)及其后视力的发展情况。结果当有效焦距F=(21-22)、密码M=(2.67—2.9)(D/mm)时,此计算值符合实验平均值(2.7)。当年龄A^*=(3,6)岁的屈光度变化已知时,我们计算其MOS预测年龄为A^*=(7.3,21.8)岁(在不同条件下)。此值反比于M值在A=6及A=3的比值或N=N—N^*,即非正视态及正视态的眼轴成长率之差。本理论也可用来预测在年龄A=25时的近视度,分别为D=-14及-0.49的上述两例情况,同时也能分析Lain等人的测量值(由出生到青年期的视力发展情况)。结论本理论可预测MOS、其后发展情况及其符合实验值(M)。使用成长率差值(dN)比使用L/rl比值能更准确地预测MOS。 相似文献
25.
Patients with carcinoma of the biliary tract have a poor prognosis because the disease is often unresectable at diagnosis. Intraluminal brachytherapy has been reported as an effective treatment for localized cholangiocarcinoma of the biliary tract. The purpose of our study was to analyse the survival of patients treated with brachytherapy and make some recommendations regarding its use. Fifteen patients underwent brachytherapy via a trans-hepatic approach at the Royal Prince Alfred Hospital from 1983 to 1993. Eleven patients had low-dose rate brachytherapy and four patients had high-dose rate treatment. There were nine males and six females. The median age was 64 years. Other treatment included bypass procedures in two patients, endoscopic stents in 14 patients and external beam irradiation in one patient. The median survival was 12.5 months and 47% of the patients survived 1 year. The only complication reported was cholangitis which was seen in one patient. There did not seem to be any difference in survival or complications between low- and high-dose rate brachytherapy. We conclude that the addition of intraluminal brachytherapy after biliary drainage prolongs survival and is a safe and effective treatment, but patients still have a high rate of local failure, and further studies will be needed to address this problem. 相似文献
26.
Uterine leiomyomas in the infertile patient: preoperative localization with MR imaging versus US and hysterosalpingography 总被引:2,自引:0,他引:2
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas. 相似文献
27.
28.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals. 相似文献
29.
Patient dosage in computed tomography 总被引:1,自引:0,他引:1
30.