首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   263篇
  免费   9篇
儿科学   46篇
基础医学   27篇
口腔科学   1篇
临床医学   17篇
内科学   63篇
皮肤病学   9篇
神经病学   21篇
外科学   47篇
综合类   2篇
预防医学   1篇
眼科学   1篇
药学   22篇
中国医学   3篇
肿瘤学   12篇
  2017年   1篇
  2015年   7篇
  2014年   3篇
  2013年   2篇
  2012年   3篇
  2011年   3篇
  2010年   6篇
  2009年   5篇
  2008年   2篇
  2007年   4篇
  2006年   19篇
  2005年   1篇
  2004年   11篇
  2003年   9篇
  2002年   1篇
  2001年   4篇
  2000年   2篇
  1999年   8篇
  1998年   23篇
  1997年   13篇
  1996年   21篇
  1995年   23篇
  1994年   12篇
  1993年   11篇
  1992年   5篇
  1991年   5篇
  1990年   2篇
  1989年   3篇
  1988年   1篇
  1987年   2篇
  1986年   2篇
  1985年   3篇
  1984年   2篇
  1983年   3篇
  1982年   2篇
  1981年   1篇
  1980年   3篇
  1979年   2篇
  1977年   2篇
  1974年   1篇
  1969年   1篇
  1967年   2篇
  1964年   4篇
  1963年   1篇
  1959年   1篇
  1958年   1篇
  1957年   3篇
  1956年   7篇
  1955年   7篇
  1954年   9篇
排序方式: 共有272条查询结果,搜索用时 15 毫秒
21.
We report a case with rapidly growing subcutaneous and intra-muscular tumours that were identical histopathologically to a pre-existing left atrial myxoma. No invasion of visceral organs or skeleton was found. This is a very rare case of metastasizing myxoma with wide dissemination and rapid metastastic growth, despite the benign appearance of the original tumour.  相似文献   
22.
This study, aimed at elucidating the epidemiological features of primary liver carcinoma developing in non-cirrhotic livers, was based on 25,103 autopsies performed between 1975 and 1984 in Trieste, Italy. These autopsies correspond to approximately 70% of all deaths that occurred in this area. Various factors allegedly related to carcinomas were analysed in reference to our previous study on cirrhotic livers and in comparison with 5,603 autopsies in Kurume, Japan. There were 28 cases of hepatocellular carcinoma (HCC), 16 of cholangiocellular carcinoma (CCC) not associated with cirrhosis in Trieste, and 48 HCC and 19 CCC in Kurume. On the basis of our findings, it was concluded that cirrhosis, regardless of its cause, is the main pathogenetic factor in HCC; it is responsible for a much higher frequency (14.2:1) than in non-cirrhotic livers, as well as for early occurrence of tumours (an average of 6 years earlier in cirrhotic liver) in Trieste. Patients in Trieste were older than those in Japan, and the frequency of HCC among all autopsies was much greater in the latter. By contrast, the influence of cirrhosis on cholangiocellular carcinoma (CCC) was negligible, as such association appeared purely coincidental or absent. The incidence of CCC among autopsies was greater in Japan. Our data on CCC were not sufficient to demonstrate any clear aetiopathogenetic association between this tumour and alcohol abuse and hepatitis B virus (HBV) infection, except for a possible aetiological role of gallstones. The frequency of CCC relative to HCC was greater in Trieste than in Japan; the incidence of HCC was much less in Trieste, whereas CCC was more frequent in Japan.  相似文献   
23.
The metallic stent has become the most common device to reduce acute occlusion and late restenosis after balloon angioplasty, but the long-term effects of metallic stents in human coronary arteries are still unknown. To overcome several problems of conventional stenting, there have been many attempts to manufacture stents made of biodegradable materials. Although some studies have noted various degrees of inflammatory responses after biodegradable stent implantation, stents made of poly-1-lactic acid (PLLA) showed high biocompatibility with minimal inflammatory response and neointimal formation in porcine coronary arteries. A clinical study of PLLA self-expanding stent implantation is underway in Japan. The initial and 6-month results are favorable and suggest the feasibility, safety, and efficacy of the PLLA biodegradable stent in humans. However, long-term follow-up with larger numbers of patients will be required to validate the long-term efficacy of PLLA stents.  相似文献   
24.
25.
BACKGROUND: The effects of preoperative androgen deprivation on the outcomes of prostate cancer patients who received radical prostatectomy and subsequent adjuvant endocrine therapy have not yet been fully evaluated. METHODS: Patients with stage A(2), B or C prostate cancers were randomized to one of two groups: group I (n = 90), who received androgen deprivation (leuprolide and chlormadinone acetate) for 3 months followed by radical prostatectomy and subsequent adjuvant endocrine therapy (leuprolide alone), and group II (n = 86), who underwent the surgery followed by 3-month androgen deprivation (leuprolide and chlormadinone acetate) and subsequent adjuvant endocrine therapy (leuprolide alone). The effects of preoperative androgen deprivation on survival, clinical relapse (serum prostate specific antigen, PSA, above the normal level, local recurrence, or distant metastases), and PSA relapse (PSA above the detectable level) were evaluated at 5 years or later after treatment. RESULTS: There were no significant differences in overall, cause-specific, clinical relapse-free, or PSA relapse-free survival rates between the two groups. In a subanalysis, no prostate cancer deaths or clinical relapses were noted in 29 patients with organ-confined disease (OCD: negativity of capsular invasion, seminal vesicle invasion, surgical margins or nodal involvement). The odds ratio for OCD depending on group assignment was 2.44 (95% confidence interval, CI 1.04-5.72), for group I, demonstrating a higher probability of having OCD. This ratio was increased to 4.00 (95% CI 1.06-15.16) if the analysis was conducted in a subpopulation with prostate specific antigen levels less than 35.6 ng/mL and with clinical stage B or C cancers. CONCLUSION: Preoperative androgen deprivation has no demonstrable benefit in 5-year outcomes for patients undergoing radical prostatectomy and adjuvant endocrine therapy. However, it did increase the probability of OCD, which was associated with no clinical relapse during the follow-up. A longer observation is needed to clarify the exact extent of the benefits in terms of survival.  相似文献   
26.
To clarify the pathogenesis of hepatic cytomegalovirus (CMV) infection, we clinicopathologically investigated 18 infants and 10 adults with cytomegalic inclusion bodies (CIB) in the liver among a total of 75 autopsy cases with CIB in any organ of the body. CMV infection was confirmed by immunohistochemistry and in situ hybridization. When CIB were present in the liver, CMV infection also tended to be systemic. All the adults were immunocompromised patients, but diseases inducing immunodeficiency were present in only two of the infants. The severe and systemic CMV infections we found in infants might have been associated with congenital CMV infection. Histotogically, hepatocyte necrosis, cholestasis, extramedullary hematopoiesis and fatty degeneration were more frequent and prominent in infants than in adults. However, inflammatory cell infiltration was only slight. In addition, the frequent association with premature birth and hypoplasia of the thymus suggested that insufficient development of immunity may result in hepatic CMV involvement in infants. CIB were most frequently observed in hepatocytes in both infants and adults, but in infants they were also frequently seen in the bile duct epithelium. These histopathological findings and the high incidence of jaundice in infant patients suggest that the bile duct is also an important site of CMV proliferation in infants, and that CMV infection may be one cause of infantile jaundice.  相似文献   
27.
28.
Abstract Two cases of sleep disordered-breathing in climacteric were reported. Polysomnography including esophageal pressure (Pes) measurement was performed. Case 1 was diagnosed as upper airway resistance syndrome. Case 2 was diagnosed as obstructive sleep apnea syndrome, while many episodes of upper airway resistance also existed. Hormone replacement therapy improved clinical symptoms, and in case 1, Pes nadir was improved but incidence of arousals which was induced by breathing disturbances was not significantly changed. Sleep disordered-breathing should be suspected as a cause of sleep disorder even in females, especially in climacteric age. Pes measurement and evaluation of arousals is required. Hormone replacement therapy may release the upper airway resistance.  相似文献   
29.
FAN, W., et.al .: Effects of the Pacing Site, Procainamide, and the Lead Configuration on the Relationship Between the Upper Limit of Vulnerability and the Defibrillation Threshold . In six open chest dogs, we determined the upper limit of vulnerability (ULV) and defibrillation threshold (DFT) by an up-down algorithm when the pacing site was at the right atrium, at the left ventricular apex, and at the left ventricular base. Monophasic shocks (6 ms) were given to epicardial patches at 20 and 40 ms before the peak of the T wave to bracket the mid-upslope. In an additional six closed-chest dogs, we determined the ULV and the DFT with transvenous leads with an 8-ms biphasic waveform. The S1 pacing site was at the right ventricular apex and the right atrium, and the shocks were given at 20 ms and 40 ms before the peak of the T wave, and on the peak of T wave. The same test was repeated after intravenous procainamide infusion (20 mg/Kg loading, then 2 mg/min maintenance). In the first six dogs, the ULV determined when pacing was given to the left ventricular apex, the left ventricular base, and the right atrium was 4.2 ± 1.7 J, 4.4 ± 2.1 J, and 3.9 ± 1.5 J, respectively; values that were not significantly different from the DFT of 4.8 ± 1.9 J, 4.5 ± 1.9 J, and 4.2 ± 1.3 J, respectively. In the latter six dogs, the ULV versus the DFT was 13.5 ± 5.2 J versus 18.2 ± 6.2 J (right ventricular apex) and 12.8 ± 6.0 J versus 15.4 ± 6.0 J (right atrium) at baseline; 14.6 ± 4.6 J versus 19.5 ± 6.7 J (right ventricular apex) and 14.3 ± 5.5 J versus 18.7 ± 6.4 J (right atrium) during procainamide infusion (P = NS for all). We conclude that, when tested with 2–3 shocks on or before the peak of the T wave, the ULV can be used to estimate the DFT with both epicardial patch and transvenous lead configurations. Different S1 pacing sites and procainamide did not change the relationship between the ULV and the DFT.  相似文献   
30.
PROBLEM : To demonstrate whether monocyte chemotactic and activating factor (MCAF) and interleukin-6 (IL-6) are present in the seminal plasma, and whether these presence is modulated by leukospermia. METHODS : Semen samples from 53 men were obtained by masturbation and examined for the presence of MCAF and IL-6 by enzyme immunoassay (EIA). Semen samples were obtained from 28 infertile men without leukospermia, 16 infertile men with leukospermia, and nine proven-fertile men. The correlation between the amount of MCAF in the seminal plasma with some spermiogram parameters and other cytokines such as IL-6 and IL-8 was statistically evaluated. RESULTS : Immunoreactive MCAF was detected in the seminal plasmas of all 53 subjects. The MCAF titer in the seminal plasma of patients with leukospermia (11.19 ± 2.75 μg/1) was significantly higher than that in the seminal plasma of the patients without leukospermia (3.24 ± 0.53 μg/1) and the fertile men (2.78 ± 0.35 μg/1) (P < 0.001). The IL-6 titer in the seminal plasma of the patients with leukospermia (21.05 ± 4.49 ng/1) was also significantly higher than that in the seminal plasma of the patients without leukospermia (8.77 ± 1.92 ng/1) and the fertile men (6.94 ± 1.27 ng/1) (P < 0.01). There was a high degree of correlation among the levels of MCAF, IL-6 and IL-8 in the seminal plasma. CONCLUSIONS : These findings demonstrated the presence of MCAF and IL-6 in the seminal plasma, and that the levels of these cytokines were elevated in the seminal plasma of the infertile patients with leukospermia.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号