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991.
A triangular echogenic area in the upper pole renal parenchyma can be identified at times during routine sonography of the right kidney. Thirty such cases are presented. Occasionally similar echogenic defects in the parenchyma can be seen posteriorly in the lower pole and in the left kidney. These defects in the parenchyma result from normal extensions of the renal sinus of kidneys that have a distinct division of their upper and lower poles. This is due to partial fusion of two embryonic parenchymatous masses called renunculi. The defects in the parenchyma occur at the junction of the renunculi; hence we have termed them junctional parenchymal defects. In order to differentiate them from pathologic conditions, one must identify their characteristic location and demonstrate continuity with the renal sinus.  相似文献   
992.
Rich  TA; Weiss  DR; Mies  C; Fitzgerald  TJ; Chaffey  JT 《Radiology》1985,156(2):527-531
Twenty-six patients with small cancers limited to the lower two-thirds of the rectum were treated with conservative surgery and radiation therapy (XRT). The selection factors for this approach were age, refusal of a permanent colostomy, or the high risk of local recurrence because of inadequate surgical margin or palpable residual tumor after local surgical treatment alone. In patients treated with local excision or fulguration followed by XRT, there was a 6% local failure rate (one in 17); in 16 of 17 patients receiving radiation doses above 4,500 cGy, the local control was complete for follow-up periods of 6 months to 7 years. In nine patients treated with XRT for residual tumor, local failure occurred in five (56%). The disease-free survival for those without residual tumor versus those with residual tumor was 88% and 44%, with median follow-up periods of 20 and 23 months, respectively. Serious late complications occurred only if total doses were greater than 6,300 cGy. Local excision combined with XRT proved to be a safe alternative to radical surgery in selected patients and resulted in excellent local control while allowing preservation of anal sphincter function.  相似文献   
993.
Data has accumulated suggesting reciprocity between cytokines and the reproductive system. The present study was performed in order to evaluate the correlation between interleukin 1 (IL-1) and tumour necrosis factor (TNF) concentrations in follicular fluid and its oestradiol, progesterone and testosterone levels. A total of 39 follicular fluid samples, from eight patients undergoing in-vitro fertilization and embryo transfer were evaluated. All of the patients were treated by a midluteal (long) protocol involving a gonadotrophin releasing hormone agonist (GnRHa) coupled with follicular phase human menopausal gonadotrophin. Mean levels in follicular fluid of IL-1, TNF, oestradiol, progesterone and testosterone were 1.58 +/- 0.42 fmol/0.1 ml, 4.69 +/- 4.18 pg/ml, 28.5 +/- 58.1 ng/ml, 2360.5 +/- 2846.3 ng/ml and 7.22 +/- 7.08 ng/ml respectively. There was a significant (P less than 0.01) positive correlation between IL-1 and progesterone levels. There was no significant correlation between the different lymphokines and oestradiol secretion, oocyte fertilization, embryo quality and pregnancy rates. It is concluded that IL-1 and TNF exist in follicular fluid. It may be hypothesized that IL-1 has a local regulatory action, possibly promoting luteinization.  相似文献   
994.
995.
PURPOSE: To determine the usefulness of technetium 99m diethyltriaminepentacetic acid (DTPA) radioaerosol inhalation-clearance scintigraphy for early detection of pulmonary complications of human immunodeficiency virus (HIV) disease in children. MATERIALS AND METHODS: A total of 301 studies were performed in 132 HIV-positive children (group 1; mean age, 46.6 months). In children born to HIV-positive mothers (group 2), 273 studies were performed in 160 children who eventually were proved to be HIV negative (mean age, 10.3 months), and 80 studies were performed in 47 HIV-positive children (mean age, 15.6 months). Radioaerosol studies were performed by using commercially available radioaerosol nebulizers. Pulmonary clearance half-time was measured by using conventional gamma camera computer systems. Radioaerosol results were correlated with indexes of pulmonary health and function. RESULTS: The HIV-negative, group 2 children had a mean radioaerosol clearance half-time (58.1 minutes; 162 studies in 108 children) similar to that reported in healthy adults. Group 1 children with pulmonary involvement exhibited a faster mean clearance half-time (28.6 minutes) than did children without evidence of pulmonary involvement from either group 1 or group 2 (P < .05). A faster pulmonary clearance rate did not simply reflect the presence of chest disease that also was detectable on radiographs (P = .3). CONCLUSION: Quantitative DTPA radioaerosol clearance studies may provide useful information about pulmonary involvement in selected children with HIV disease.  相似文献   
996.
目的:探讨超声在乳腺肿瘤的诊断与鉴别诊断中的应用价值。方法:阅读国内外相关文献进行综述。结果:高频二维超声可以清晰显示乳腺及肿瘤的细微结构;彩色多普勒血流显像可以提供有关肿瘤周边及内部的血流情况;彩色多普勒能量图丰富了血流信息,提高了多普勒探测的敏感性。结论:灰阶超声、CDFI、CDE几种技术相结合,必将提高乳腺肿瘤诊断与鉴别诊断的准确性。  相似文献   
997.

Purpose

We attempted to assess the natural course of vesicoureteral reflux after it was detected in asymptomatic siblings of children with reflux, and to determine predictors of and time to resolution.

Materials and Methods

We reviewed the records and radionuclide cystograms of 76 girls and 32 boys 2 weeks to 103 months old (mean age 21 months) with vesicoureteral reflux detected in a sibling screening program. Predictors were determined using logistic regression and survival analysis.

Results

Vesicoureteral reflux resolved in 52.8 percent of cases at a mean followup of 18.5 months. Yearly resolution rates exceeded 28 percent. Predictors of the likelihood of resolution were not identified. At diagnosis unilateral reflux and mild reflux were independent and univariate predictors, respectively, of more rapid resolution.

Conclusions

By showing that spontaneous resolution is likely for children with vesicoureteral reflux detected in a sibling screening program, this study supports nonsurgical management with annual imaging evaluation.  相似文献   
998.
Biopsies of human embryonic cell preparations previously analysed by cytogenetic and/or fluorescent in-situ hybridization (FISH) chromosome probes provide a unique reference DNA resource for the archival preimplantation genetic diagnosis (PGD) of the transferred embryo. DNA polymerase chain reaction (PCR) may be utilized on these fixed cell preparations to verify equivocal FISH/PGD results. Retrospective PCR screens of the genotype of biopsied embryonic cell(s) may be of benefit in the case of a suspected genetic mutation. Currently, carrier detection or linkage analysis is often not possible because of early death of the fetus, or of patients with a lethal disease. Alternatively, fixed/stained 'failed fertilized' oocytes provide a resource to extend genetic analysis to infertile patients. A successful research is described which minimizes loss of individual analysed fixed/stained oocytes, metaphase chromosomes, and embryonic cell samples. Initial DNA amplification takes place in situ using a modified PCR protocol. Comparative cellular studies using primer sets previously used for PGD analyses show that 65% of the preparations amplified unequivocally using the modified protocol and primers for a CA repeat motif gene sequence, in comparison with 81% using the original PCR protocol. With further refinement and optimization, the methods outlined have the potential to retrospectively screen archival fixed chromosomes, gametes, and embryonic cells for clinical application, and enable the further study of the fixed human preimplantation embryo at the morphological, cell and molecular level.   相似文献   
999.
基于声速微扰的松质骨超声参数分析和计算   总被引:2,自引:2,他引:2  
在生物组织非均匀连续介质模型的基础上,采用声速微扰法,通过分别改变入射频率、松质骨孔隙度及骨小梁特征尺寸等三个参数,对松质骨中的超声背向散射系数和由于散射而引起的衰减进行了分析。分析结果表明:由于散射而引起的衰减占松质骨中总的超声衰减的26%左右;当松质骨孔隙度在0.61附近时,衰减和背向散射系数均达到最大值。  相似文献   
1000.
Interleukin-1 (IL-1) is an important mediator in inflammation and immunological processes. The findings of native IL-1 inhibitors suggest a negative feedback mechanism to down-regulate IL-1 mediated acute inflammation. IL-1 inhibitors were also found elevated in disease states associated with high IL-1 levels. We have previously described one such IL-1 inhibitor derived from the human M20 myelomonocytic cell line. In this paper we present several biological and biochemical characteristics of the M20 IL-1 inhibitor. Various in vitro activities of the inhibitor are described and its IL-1 specificity in these assays is demonstrated. Purification of the inhibitor was performed by DEAE-high performance liquid chromatography, isoelectric focusing, gel filtration and dye ligand chromatography column. This protein factor has a MW of 52 +/- 4 kDa and a pI of 4.15 +/- 0.1. The inhibitor has no cross-reactivity against a panel of known cytokines (IL-1 alpha, IL-1 beta, IL-2, sIL-2R, IL-6, tumor necrosis factor (TNF), interferon-gamma (IFN-gamma)) and is distinct from the IL-1 receptor antagonist (IL-1ra). The purified IL-1 inhibitor was destroyed by trypsin, 2-mercaptoethanol, sodium dodecyl sulfate and extremes in pH and in temperature. Only IL-1 induced (but not the IL-2, IL-6 or TNF induced) thymocyte proliferation and PGE2 production by fibroblasts were inhibited by the inhibitor, thus showing specificity to IL-1 in these assays.  相似文献   
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