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111.
The presence of testosterone in yolk sac tumor of the infant testis was investigated immunohistochemically. All 16 cases tested were positive for the hormone. The antigen-positive tumor cells were primitive mesenchymal cells and columnar cells forming small ducts, which resembled Leydig cells and Sertoli cells, respectively. These cells accounted for about 1 to 20% of tumor cells and were intermingled with typical yolk sac structures. In contrast, no yolk sac tumor of adult testis was definitely positive for the antigen. In view of its distinctive histological and immunohistochemical features and clinical behavior, yolk sac tumor in the infant testis is most likely a separate and specific entity, composed of a mixture of germ cell and sex cord stroma derivatives.  相似文献   
112.
One hundred forty previously untreated cases of T1N0M0 glottic carcinoma underwent therapy at our department from November 1977 through May 1984. Ninety-six of them were treated with the open-field technique of 4 MVX-ray using parallel opposed fields in bandage up to April 1982 (group I). The remaining 44 cases were treated with the wedge-filtered technique in a plastic shell in order to improve the dose distribution and immobilization during radiotherapy starting in May 1982 (group II). The two-year disease-free survival rates were 85% and 91%, respectively. Thus, better results were achieved by improved treatment techniques.  相似文献   
113.
114.
Global and regional mucociliary clearance and transport in the lungs was studied in 20 patients with bronchiectasis by radioaerosol inhalation lung cine-scintigraphy and the quantitative analysis following inhalation of ultrasonically-generated 99mTc-tagged human serum albumin aerosol (mass median diameter; 1.93 microns with geometric s.d. of 1.52). In bronchiectatic lung regions, deposition of inhaled aerosol was diminished or inhomogeneous. Transport of inhaled radioactivity from the bronchiectatic regions was deranged in 95% of the patients (19/20). The following abnormal mucous transport patterns were regionally observed; stasis in 12 of the 20 patients (12/20), regurgitation or reversed transport in 14/20, straying in 8/20, spiral or zigzag transport in 1/20, and/or various combinations of these four abnormal transport patterns. When coughs occurred, regurgitation and stray became more marked in the bronchiectatic regions. These regional abnormalities in mucociliary transport seem to be responsible for the development of infections and hemoptysis in the bronchiectatic regions.  相似文献   
115.
116.
Development of multiple transitional cell carcinomas in the urinary tract   总被引:2,自引:1,他引:1  
The multiplicity of transitional cell carcinomas in the renal pelvis, ureter and bladder was analyzed in terms of (1) tumor configuration, i.e., papillary, nodular cancers, (2) associated mucosal changes such as carcinoma in situ (CIS) and dysplasia and (3) the possible involvement of human papillomavirus (HPV) in the development of multiple papillary cancers in the bladder. The incidences of concurrent or subsequent bladder cancer in renal pelvic cancer and/or ureteral cancer cases were 7/31 (22%) for renal pelvic cancer, 17/28 (60%) for ureteral cancer and 10/15 (67%) for renal pelvic and ureteral cancer. In 33 cases of renal pelvic and/or ureteral cancer occurring since 1978, 67% of the papillary and 13% of the nodular cancers in the upper tract exhibited a simultaneous or later development of bladder cancer. In 211 cases of bladder cancer for which cystectomy was performed, 77% of the papillary cancers arose in multiple form, 57% being associated with CIS and/or dysplasia, whereas 72% of the nodular cancers developed singly, 55% being associated with CIS and/or dysplasia. No positive signals hybridizing to HPV types 1, 5, 6, 11, 16, 17, 18, 20, 33 and 38 were detected in any of 19 papillary bladder cancers and 13 specimens of normal bladder mucosa under conditions of low stringency, suggesting that HPV may not be a factor in multiple bladder tumor development. Definite findings from the present study are: (1) there is multiple development of papillary cancers but they remain superficial, whereas nodular cancers develop singly and are invasive, (2)) there was no steady tendency towards a relation between multiplicity and associated mucosal changes, (3) HPV was not, to our knowledge, involved in the multiple development of papillary cancers in the bladder.  相似文献   
117.

OBJECTIVE

To evaluate the clinical results of radiotherapy (RT) for patients with regionally localized hormone‐refractory prostate carcinoma (HRPC).

PATIENTS AND METHODS

As part of a Patterns of Care Study in Japan, a nationwide survey was conducted of RT for patients with prostate adenocarcinoma. We reviewed the detailed information of 140 patients with regionally localized HRPC who received RT between 1996 and 1998, and between 1999 and 2001, in 117 randomly selected institutes in Japan. The median (range) age of the patients was 74 (51–94) years, and their tumours were defined as well (14), moderately (51) or poorly (54) differentiated, or of unknown differentiation (21). The median (range) interval between hormonal therapy (HT) and RT was 32.5 (1.1–168.4) months. Ninety‐five patients had T3‐4 tumours and 28 had regional lymph node metastases before treatment. The median (range) prostate‐specific antigen levels before the initial HT and before RT were 35.0 (1.5–276) and 10.0 (0.06–760.3) ng/mL, respectively. External beam RT was administered, with a median total dose of 66 Gy; 70 patients (50%) received pelvic irradiation.

RESULTS

At a median follow‐up of 20.7 months, the 5‐year overall and clinical progression‐free survival rates (95% confidence interval) were 48.1 (36–60)% and 36.7 (26–47)%, respectively. Although there were distant metastases in 46 patients, only six had local progression. There was late morbidity of grade ≥3 in six patients.

CONCLUSION

To the best of our knowledge, this study comprises the largest series of regionally localized HRPC treated with RT reported to date. RT might have a limited role for HRPC, because in most patients RT failed, with distant metastasis.  相似文献   
118.
In the screening test of lung cancer, we found that there was a high prevalence of cases with pleural plaque recognized by chest X-ray film in inhabitants living in A town in Kumamoto Prefecture. We detected abnormal pleural plaque in 148 (41.5%) of 357 cases received lung cancer screening. These pleural plaques resulted in pleural thickening and calcification. Two or three mines of serpentine and an asbestos factory existed in this region from 1883 until 1970. Although twelve cases had a history of factory work, none had fibrous changes in the lung fields on chest X-ray films. It was considered that the pleural plaque probably resulted from exposure to low doses of asbestos in the atmosphere or contact with asbestos workers in their homes. The incidence of lung cancer in this region was not higher than that in other regions in Kumamoto Prefecture. There were no cases of malignant mesothelioma in our hospital during the past eleven years.  相似文献   
119.
A retrospective analysis of 22 patients with central nervous system (CNS) non-Hodgkin's lymphomas seen from 1978 to 1989 at Hamamatsu University Hospital was carried out. These were corresponding to 16% (22/137) of non-Hodgkin's lymphomas treated by irradiation during the same period. Six patients had primary intracranial involvement, six had secondary one, five had leptomeningeal involvement and five had spinal cord compression. Median survival of these groups 29 months, 7 months, 6 months and 4 months, respectively. On the case primary intracranial involvement, neurological signs and symptoms and performance status (PS) were improved in most patients. Whole brain irradiation with a dose of 45 Gy to 50 Gy followed by systemic chemotherapy was considered as effective treatment modalities. On the other hands, for the secondary intracranial lymphomas, clinical symptoms and PS were excellently improved by radiation therapy, however these were not reflected to survival. The conditions having primary site on gastrointestinal tract and relapse as systemic dissemination were considerable risk factors for the control of CNS involvement. For these patients, prophylactic chemotherapy should be necessary. Improvement of PS on patients with leptomeningeal lymphomas was obtained in only 3 of 5 cases. These were treated by irradiation on whole spine or neuroaxis and intrathecal MTX injection. We observed 2 cases dying from cerebrovascular accident and one case from leukoencephalopathy. This showed that such combination therapy should be carefully attempted. Five patients having spinal cord compression suffered from paraplegia and none of them had been improved on their symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
120.
A proposed simplification of radioaerosol inhalation lung cine-scintigraphy, namely 60 min measurement of radioactivity without repeating measurement at 24 hr later and calculation of alveolar deposition ratio (ALDR) by the regression formula of ALDR = -48.08 + 0.47 X FEV1.0% + 0.59 X LRR60, was found useful and applicable even to the evaluation of a drug on mucociliary clearance mechanisms. The simplified method indicated a very similar evaluation of the effect of bromhexine on airway clearance efficiency with those actually revealed by the original method.  相似文献   
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