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   448篇
  免费   24篇
  国内免费   1篇
儿科学   29篇
妇产科学   3篇
基础医学   31篇
口腔科学   10篇
临床医学   42篇
内科学   133篇
皮肤病学   23篇
神经病学   38篇
外科学   75篇
综合类   1篇
预防医学   20篇
眼科学   2篇
药学   28篇
肿瘤学   38篇
  2022年   2篇
  2021年   4篇
  2018年   2篇
  2017年   9篇
  2016年   2篇
  2015年   9篇
  2014年   13篇
  2013年   16篇
  2012年   8篇
  2011年   5篇
  2010年   19篇
  2009年   19篇
  2008年   6篇
  2007年   7篇
  2006年   15篇
  2005年   14篇
  2004年   9篇
  2003年   8篇
  2002年   4篇
  2001年   11篇
  2000年   5篇
  1999年   8篇
  1998年   16篇
  1997年   33篇
  1996年   21篇
  1995年   34篇
  1994年   11篇
  1993年   18篇
  1992年   12篇
  1991年   6篇
  1990年   4篇
  1989年   5篇
  1988年   3篇
  1987年   2篇
  1986年   5篇
  1985年   4篇
  1984年   4篇
  1983年   4篇
  1982年   5篇
  1981年   2篇
  1980年   4篇
  1979年   2篇
  1978年   2篇
  1963年   1篇
  1959年   7篇
  1958年   7篇
  1957年   19篇
  1956年   20篇
  1955年   12篇
  1954年   10篇
排序方式: 共有473条查询结果,搜索用时 15 毫秒
51.
Patients with idiopathic acquired sideroblastic anaemia (IASA) usually show macrocytic or normocytic anaemia and increased free erythrocyte protoporphyrin (FEP). The mean cell haemoglobin concentration is normal or slightly low. Here we report a pyridoxine-responsive IASA patient with microcytic and hypochromic anaemia and low FEL level; these features are usually seen in cases of hereditary sideroblastic anaemia. Microcytosis increased during therapy.
There may be a subgroup of IASA with microcytic and hypochromic anaemia, low normal FEP and some response to pyridoxine like hereditary sideroblastic anaemia.  相似文献   
52.
The recombinant bacillus Calmette–Guérin (rBCG) secretion system utilizing an extracellular α antigen of Mycobacterium kansasii (α-K) was characterized biochemically and immunologically. The human immunodeficiency virus type1 (HIV-1) p17 gag B cell epitope fused to α-K was secreted in extremely large amounts. At least three mice out of seven inoculated with rBCG generated high titres of antibody to the epitope. The long-lasting antibody production persisted more than 14 months.  相似文献   
53.
Abstract The aims of the present study were to clarify the findings of magnetic resonance imaging (MRI) in the aging brain, and to relate the MRI findings to higher order cortical function. A total of 118 healthy aged volunteers (41 men, 77 women) underwent cranial MRI electroencephalography (EEG), Benton visual retention test (BVRT) and interview. The subjects had no past history or clinical evidence of cerebrovascular disorder, head trauma or dementia and were living at home without any difficulty. The majority of the subjects have participated in this series of studies since 1982. Using a 1.5 T superconductive MR instrument, T1-weighted, proton density and T2-weighted images were obtained. The MRI data were rated visually by regarding 12 items according to fixed criteria. T2 high signal intensity (T2HSI) lesions were found in 69.5% of subjects, the prevalence of which increased with age. T2HSI lesions were most frequently found in the basal ganglia (61.9%), followed by the thalamus (39.0%), parietal lobe (37.0%), temporal lobe (12.7%) and pons (8.5%). Among these lesions, lacunar infarction showed low signal intensity in T1-weighted images and was found in 24.6% of subjects, the prevalence also increasing with age. These findings, including brain atrophy determined according to similar criteria, were correlated closely with the subjects' age. The results of BVRT showed a close relation with T2HSI, suggesting that T2HSI may influence cognitive function. When the subjects were classified according to the presence of T2HSI, lacunar infarction and EEG abnormalities, brain atrophy was significantly milder in a group of subjects with T2HSI(-), lacunar infarction(-) and normal EEG than in the other groups. This suggests that changes seemingly representing physiological aging may be promoted by another pathological which also exerts influences on higher order cerebral function.  相似文献   
54.
Congenital bile duct cysts are now a well-documented anomaly of the biliary tree, and have become more common in Japan. Familial occurrence of congenital bile duct cysts, however, is extremely rare, with only six reported cases in the literature. We report a familial pattern of congenital bile duct cysts in a mother and her daughter. A 33-year-old female was admitted for evaluation of right upper quadrant abdominal pain and fever 6 days after an uneventful delivery of her second child. A com- puted tomography (CT) and ultrasound scan (US) revealed an obstructed biliary tract. Percutaneous transhepatic biliary drainage was then performed, and a cholangiogram revealed a Scholtz type B choledochocele without an anomalous connection of the pancreaticobiliary ducts. Endoscopic US demonstrated that the choledochocele was associated with a stone in the cyst. A pylorus-preserving pancreatoduodenal resection was performed, and a histological study revealed that the choledochocele was lined by biliary mucosa without evidence of malignancy. The newborn infant had an abdominal tumour. An US and CT revealed a congenital bile duct cyst. An operation was performed and the intraoperative cholangiogram showed an Alonso-Lej type I congenital bile duct cyst with an anomalous connection of the pancreaticobiliary ducts. Whether congenital bile duct cysts are hereditary remains to be elucidated.  相似文献   
55.
OBJECTIVE: To assess the clinical efficacy of endoscope-assisted minilaparotomic radical retropubic prostatectomy (EAM-RRP) compared with conventional radical retropubic prostatectomy (cRRP). METHODS: From September 2001 to December 2003, 30 patients with localized prostate cancer were treated by EAM-RRP. The surgical manipulation was performed through the wound with thoracoscopic assistance, using standard surgical instruments. In all cases, 800 mL of blood was collected from the patient for autotransfusion. For both EAM-RRP and cRRP, the internal iliac and obturator lymph nodes were dissected before the prostate removal. Clinical indicators such as operation time, blood loss, and duration of postoperative urine incontinence were analysed in the two groups. RESULTS: The postoperative period before ambulation and the duration of postoperative urine incontinence were significantly shorter after EAM-RRP than after cRRP, while no significant difference was found in operation time, blood loss, and duration of urethral catheterization. None of the cases required allotransfusion. CONCLUSION: EAM-RRP, which had a shorter postoperative period before ambulation and continence, is considered a safe and useful technique for radical prostatectomy.  相似文献   
56.
57.
AIM: To evaluate the feasibility and usefulness of high dose chemotherapy including paclitaxel (T-ICE) combined with peripheral blood stem cell transplantation (PBSCT) for male germ cell tumor. METHODS: Five male patients with advanced germ cell tumor underwent 1-6 courses of high dose chemotherapy including paclitaxel (T-ICE; 175 mg/m2 of paclitaxel, 1250 mg/m2 of carboplatin, 1500 mg/m2 of etoposide and 7.5 g/m2 of ifosfamide) with PBSCT after 2-3 courses of induction chemotherapy (PEB or VIP). RESULTS: In all patients, serum marker levels decreased to within the normal range by T-ICE. Two patients underwent resection of residual tumor. In one patient, viable cancer cells were detected in resected lymph node tissue and adjuvant chemotherapy was then performed. Although the follow-up period was short (7-15.5 months), four of the five patients (80%) showed no evidence of recurrent disease. No significant differences in side-effects were noted between T-ICE and conventional high dose ICE, which was previously performed in 39 patients at the Division of Urology, Kobe University Graduate School of Medicine, Japan. CONCLUSIONS: High dose chemotherapy, including T-ICE, combined with PBSCT showed an almost identical degree of side-effects as seen in previous high dose chemotherapy without paclitaxel. Although 80% of the patients showed no evidence of disease so far, the efficacy of T-ICE should be evaluated with more patients and longer follow up.  相似文献   
58.
Abstract— N,N-Dimethylcarbamoylmethyl α,2-dimethyl-5H-[1]-benzopyrano[2,3-b]pyridine-7-acetate (Y-23023) is a prodrug developed as a new non-steroidal anti-inflammatory drug (NSAID). Y-23023 is rapidly hydrolysed to an active metabolite, α,2-dimethyl-5H-[1]benzopyrano[2,3-b]pyridine-7-acetic acid (M1) following its absorption and then exhibits a strong anti-inflammatory activity. We have examined the pharmacokinetic behaviour in polymorphonuclear leucocytes (PMNs) of M1 and of indomethacin after oral administration to rats of Y-23023 and indomethacin, respectively. Y-23023 was rapidly absorbed, producing a mean Cmax (1·13 μg mL?1) of M1 after 1 h in plasma. Indomethacin was less rapidly absorbed, producing a mean Cmax (3·38 μg mL?1) after 3 h in plasma. The mean AUC of M1 and indomethacin in plasma were 5·45 μg h mL?1 and 22·49 μg h mL?1, respectively. The mean tmax, Cmax and AUC of M1 in PMNs were 1 h, 11·1 ng (41 pmol)/108 cells and 58·6 ng (164 pmol) h/108 cells, respectively. The same parameters for indomethacin in the PMNs were 3 h, 15·4 ng (57 pmol)/108 cells and 95·2 ng (266 pmol) h/108 cells, respectively. The PMNs/plasma ratio of M1 was about 2·8 times that of indomethacin. These results indicate that the association of M1, an active metabolite of Y-23023, from blood to the PMNs is greater than that of indomethacin.  相似文献   
59.
Abstract— Sulphadimethoxine (SDM), and its metabolites, N4-acetyl SDM, N1-(2-methyl-6-hydroxy-4-pyrimidinyl) sulphanilamide (6-OH-SDM), N1-(6-methyl-2-hydroxy-4-pyrimidinyl) sulphanilamide (2-OH-SDM), N1-(2,6-dihydroxy-4-pyrimidinyl) sulphanilamide (2,6-diOH-SDM) and SDM N1-glucuronide in chicken tissues were extracted, partially purified by Bond Elute SCX cartridges, and assayed and identified by HPLC/LC-MS after administration of SDM to chickens. During the administration and 24 h after withdrawal, SDM and 6-OH-SDM were observed in almost all tissues and excreta. N4-Acetyl SDM and 2,6-diOH-SDM were observed in some tissues, but 2-OH-SDM and SDM N1-glucuronide were observed in a few limited tissues. Twenty four hours after withdrawal, SDM and its metabolites, except 6-OH-SDM, decreased. SDM and its metabolites were eliminated from all tissues within 48 h of withdrawal.  相似文献   
60.
Accidental transmission of contagious pathogens, especially hepatitis C virus (HCV), by needlestick or other means as an occupational hazard for medical staff is of concern. We retrospectively analysed cases of work-related accidental injury with pathogens such as hepatitis B virus (HBV), HCV, syphilis and human immunode?ciency virus (HIV) reported to the centres for disease control at 15 hospitals (total 5776 beds) in the Gunma prefecture, Japan, from December 1990 to August 1993 (24.7 months). There were 416 such cases (16.8 cases/month), with an incidence of 0.2–3.5 accidents per month per hospital. Such accidents occurred in 297 (71.2%) nurses, 98 (23.5%) medical doctors, 13 (3%) laboratory technicians, four (1.0%) hospital maintenance workers, one (0.2%) assistant nurse, one secretary and two others. There were 323 (77.6%) injuries caused by needlestick, 42 (10.1%) from suture needles or surgical knife cuts, 17 (4.1%) from blood splatters from patients into the eyes or mouth, 10 (2.4%) from contact with injured skin and 24 (5.8%) simple skin contacts. Of the pathogens, 60.3% were HCV, 22.6% HBV, 5.8% syphilis, 0.7% HIV and 10.6% were of unknown origin. Four cases (1.6%) of HCV infection were found and treated with one or two courses of interferon therapy, and HCV was subsequently cleared. All four patients were cured with interferon therapy. None of the HBV-injured cases resulted in infection, possibly because of prophylaxis with HB immunoglobulin and HB vaccine. No HIV or syphilis infection was contracted. In summary, chronic HCV infection acquired as an occupational hazard can be cured by appropriate treatment, such as with interferon, after early detection of the infection.  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