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31.
CHAN CHS; CHAN RCY; ARNOLD M; CHEUNG H; CHEUNG SW; CHENG AFB 《QJM : monthly journal of the Association of Physicians》1992,82(1):15-23
A prospective study of the efficacy of bronchoscopy and tuberculostearicacid assay in the diagnosis of sputum smear-negative pulmonarytuberculosis (TB) was carried out in 39 patients with symptomsand radiographic changes suggestive of active pulmonary TB.The diagnosis of TB was confirmed in 15 patients, probable TBwas diagnosed in eight and 16 patients did not have TB. An earlydiagnosis of TB was made by bronchoscopy in six patients (40per cent). Culture of sputum obtained before bronchoscopy waspositive in nine patients (60 per cent) while combined withbronchoscopy specimens, a positive mycobacterial culture wasobtained in 12 patients (80 per cent). Mycobacteria were culturedfrom transbronchial biopsy specimens from five patients (33per cent) but none of these was exclusively positive. Histologicalexamination of transbronchial biopsy tissue was diagnostic ofTB in four patients and it was the exclusive means of earlydiagnosis in two. Transbronchial biopsy also provided an alternativediagnosis in four other patients. Tuberculostearic acid assayhad a sensitivity of 0.40 in bronchial aspirate, 0.80 in bronchoalveolarlavage fluid, and 0.27 in transbronchial biopsy specimens: thecombined result was 0.87. In nine patients with pulmonary TBin whom an early diagnosis could not be made, the tuberculostearicacid assay was positive in seven (78 per cent). We concludethat bronchoscopy with bronchoalveolar lavage and transbronchialbiopsy is helpful in providing early diagnosis and positiveculture results. Assay of tuberculostearic acid in bronchoalveolarlavage fluid is a useful adjunct to early diagnosis. However,mycobacterial culture and assay of tuberculostearic acid intransbronchial biopsy specimens have little diagnostic value. 相似文献
32.
心肌梗死大鼠心肌细胞凋亡及磷酸肌酸的干预 总被引:3,自引:0,他引:3
目的:缺血引起的心肌能量供应不足是心肌细胞凋亡主要的因素之一,观察补充外源性能量磷酸肌酸对缺血心肌细胞凋亡和心功能的影响。方法:实验于2003-04/06在解放军总医院老年心血管病研究所实验室完成。选用SD大鼠50只,按随机数字表法分为3组:①磷酸肌酸组19只,结扎左冠状动脉制作心肌梗死模型,结扎前30min按200mg/kg的剂量腹腔注射磷酸肌酸1次。②缺血对照组21只,心肌缺血方法同磷酸肌酸组,结扎前30min腹腔注射相同体积的50g/L葡萄糖注射液1次。③正常对照组10只,仅在冠状动脉下穿线,不结扎冠状动脉,其余同缺血对照组。结扎冠状动脉6h后,取各组大鼠心脏标本做石蜡切片,缺口末端标记法染色,高倍镜下计数心肌细胞凋亡指数,凋亡指数=凋亡心肌细胞数/心肌细胞总数;取心脏标本前,测左心室收缩压、舒张末压和压力变化速度,并进行组间比较。结果:磷酸肌酸组大鼠造模时死亡9只;缺血对照组造模时死亡10只,造模成功后6h内死亡1只,进入结果分析共30只大鼠,每组10只。①缺血对照组大鼠的左心室舒张末压显著高于正常对照组[(13.9±5.3vs.2.8±3.2)mmHg(P<0.01)],左心室压力变化速度显著低于正常对照组[(705.8±111.7vs.1141.7±94.5)mmHg/s(P<0.01)];磷酸肌酸组大鼠的左心室舒张末压显著低于缺血对照组[(8.9±3.5)mmHg(P<0.05)];左心室压力变化速度显著高于缺血对照组[(841.5±76.1)mmHg/s(P<0.01)];左心室收缩压与缺血对照组差异无显著性意义(P>0.05)。②磷酸肌酸组大鼠的心肌细胞凋亡指数显著低于缺血对照组(0.203±0.054vs.0.278±0.052,P=0.006)。结论:补充外源性能量磷酸肌酸可以减少缺血后心肌细胞凋亡,并改善心功能,磷酸肌酸抑制缺血心肌细胞凋亡可能是改善心肌梗死后心功能的主要作用途径之一。 相似文献
33.
OBJECTIVE: This was a double-blind, randomized multicentre trial comparing efficacy and safety of brivudin (125 mg, once a day) and famciclovir (250 mg, three times a day), both given orally for 7 days, in the treatment of herpes zoster. METHODS: A total of 2027 immunocompetent zoster patients>or=50 years with zoster-related pain at presentation were included. Outcome measures embraced prevalence of postherpetic neuralgia (PHN), defined as at least moderate pain 3 months after treatment initiation, duration of PHN, prevalence and duration of zoster-associated pain (ZAP), duration of vesicle formation and rash healing. RESULTS: The prevalence of PHN at month 3 was 11.3% with brivudin and 9.6% with famciclovir [per-protocol (PP) population]. Equivalence of the two drugs could be demonstrated (P=0.01, PP and intention-to-treat analysis). The median duration of PHN was 46.5 days with brivudin and 58 days with famciclovir (P=0.54, PP analysis). Prevalence and duration of ZAP did not differ significantly between treatment groups. The prevalence of PHN was higher in patients>or=65 years (brivudin: 16.4%, famciclovir: 16.4%), and in patients with severe rash (brivudin: 13.4%, famciclovir: 15.7%), without significant differences between treatment groups. In patients>or=65 years, median duration of PHN was shorter with brivudin than with famciclovir (39.5 vs. 57.5 days), although the difference was not statistically significant. The two drugs had equivalent efficacy in being able to accelerate the stop of vesicle formation, and lesion healing. Adverse events were similar in nature and prevalence among groups. CONCLUSIONS: The study demonstrated equivalent efficacy of brivudin and famciclovir in the treatment of herpes zoster regarding the prevention of chronic pain and the resolution of signs and symptoms of acute herpes zoster. Compared with famciclovir, brivudin provides equivalent efficacy and safety at a more convenient once-daily dose schedule. 相似文献
34.
Morgan-Lappe SE Tucker LA Huang X Zhang Q Sarthy AV Zakula D Vernetti L Schurdak M Wang J Fesik SW 《Cancer research》2007,67(9):4390-4398
To identify new candidate cancer drug targets, we used RNAi as a tool to functionally evaluate genes that play a role in maintaining human tumor cell survival. We screened a small interfering RNA (siRNA) library directed against approximately 3,700 individual genes to assess the ability of siRNAs to induce cell death in an in vitro cell cytotoxicity assay. We found that siRNAs specifically targeting ras-related nuclear protein (Ran), targeting protein for Xenopus kinesin-like protein 2 (TPX2), and stearoyl-CoA desaturase 1 (SCD1), significantly reduced the survival of multiple human tumor cell lines. Further target validation studies revealed that treatment with Ran and TPX2 siRNAs differentially reduced the survival of activated K-Ras-transformed cells compared with their normal isogenic counterparts in which the mutant K-Ras gene had been disrupted (DKS-8). Knockdown of Ran and TPX2 in activated mutant K-Ras cells selectively induced S-phase arrest or transient G(2)-M arrest phenotypes, respectively, that preceded apoptotic cell death. Given our observations that Ran and TPX2 depletion preferentially reduces the survival of activated K-Ras-transformed cells, these two proteins may serve as useful anticancer targets in tumors expressing the activated K-Ras oncogene. 相似文献
35.
Tahir SK Yang X Anderson MG Morgan-Lappe SE Sarthy AV Chen J Warner RB Ng SC Fesik SW Elmore SW Rosenberg SH Tse C 《Cancer research》2007,67(3):1176-1183
ABT-737 is a novel and potent Bcl-2 antagonist with single-agent activity against small-cell lung cancer (SCLC) cell lines. Here, we evaluated the contribution of Bcl-2 family members to the in vitro cellular response of several SCLC cell lines to ABT-737. Relatively higher levels of Bcl-2, Bcl-X(L), Bim and Noxa, and lower levels of Mcl-1 characterized na?ve SCLC cell lines that were sensitive to ABT-737. Conversely, a progressive decrease in the relative levels of Bcl-2 and Noxa and a progressive increase in Mcl-1 levels characterized the increased resistance of H146 cells following chronic exposure to ABT-737. Knockdown of Mcl-1 with small interfering RNA sensitized two resistant SCLC cell lines H196 and DMS114 to ABT-737 by enhancing the induction of apoptosis. Likewise, up-regulation of Noxa sensitized H196 cells to ABT-737. Combination treatment with DNA-damaging agents was extremely synergistic with ABT-737 and was associated with the down-regulation of Mcl-1 and the up-regulation of Noxa, Puma, and Bim in H196 cells. Thus, SCLC cells sensitive to ABT-737 expressed the target proteins Bcl-2 and Bcl-X(L), whereas Mcl-1 and factors regulating Mcl-1 function seem to contribute to the overall resistance of SCLC cells to ABT-737. Overall, these observations provide further insight as to the mechanistic bases for ABT-737 efficacy in SCLC and will be helpful for profiling patients and aiding in the rational design of combination therapies. 相似文献
36.
Peripheral vascular disease is a serious and frequent problem in diabetic patients. Since the beginning of the widespread use of erythropoietin (EPO), we have noted an increase in peripheral vascular disease in diabetic patients receiving peritoneal dialysis and erythropoietin. This prompted us to study the effects of erythropoietin on peripheral vascular disease in patients receiving peritoneal dialysis. We retrospectively reviewed medical records of all diabetic patients in our program who received peritoneal dialysis from 1990 to 1996. Demographic and laboratory data as well as EPO use data were collected. Hospital days and occurrence of vascular events (defined as peripheral vascular surgery, amputation, or recommendation of vascular surgery or amputation by a vascular surgeon) were determined for diabetic patients receiving peritoneal dialysis. Comparisons were made between those who received EPO and those who did not received EPO, as well as comparing vascular events in 28 patients who received peritoneal dialysis before and after beginning EPO. Patients who received erythropoietin were found to have a significantly shorter time to a first vascular event, a greater number of vascular events, and more hospital days associated with vascular disease than diabetic patients who did not receive erythropoietin. With multivariate analysis, significant risk factors for the development of peripheral vascular disease in these patients were erythropoietin use, erythropoietin dose, and smoking. Twenty-eight patients who initially performed peritoneal dialysis without receiving EPO, and later received EPO, had a significant increase in vascular events, including amputations only while receiving EPO. We found the use of erythropoietin to be associated with peripheral vascular events in diabetic patients who receive peritoneal dialysis. Further investigation is warranted. 相似文献
37.
A randomized prospective comparison of oral versus intraperitoneal ofloxacin as the primary treatment of CAPD peritonitis 总被引:1,自引:0,他引:1
Ignatius KP CHENG SL LUI GX FANG PY CHAU SW CHENG Frances H CHIU TM CHAN WK LO BY CHOY CY LO 《Nephrology (Carlton, Vic.)》1997,3(6):431-435
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis. 相似文献
38.
39.
Raymond SW Tsang Dennis KS Law Rita R Gad Tim Mailman Gregory German Robert Needle 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2015,26(6):299-304
BACKGROUND:Serogroup B Neisseria meningitidis (MenB) has always been a major cause of invasive meningococcal disease (IMD) in Canada. With the successful implementation of a meningitis C conjugate vaccine, the majority of IMD in Canada is now caused by MenB.OBJECTIVE:To investigate IMD case isolates in Atlantic Canada from 2009 to 2013. Data were analyzed to determine the potential coverage of the newly licensed MenB vaccine.METHODS:Serogroup, serotype and serosubtype antigens were determined from IMD case isolates. Clonal analysis was performed using multilocus sequence typing. The protein-based vaccine antigen genes were sequenced and the predicted peptides were investigated.RESULTS:The majority of the IMD isolates were MenB (82.5%, 33 of 40) and, in particular, sequence type (ST)-154 B:4:P1.4 was responsible for 47.5% (19 of 40) of all IMD case isolates in Atlantic Canada. Isolates of this clone expressed the PorA antigen P1.4 and possessed the nhba genes encoding for Neisseria heparin-binding antigen peptide 2, which together matched exactly with two of the four components of the new four-component meningococcal B vaccine. Nineteen MenB isolates had two antigenic matches, another five MenB and one meningitis Y isolate had one antigenic match. This provided 75.8% (25 of 33) potential coverage for MenB, or a 62.5% (25 of 40) overall potential coverage for IMD.CONCLUSION:From 2009 to 2013, IMD in Atlantic Canada was mainly caused by MenB and, in particular, the B:4:P1.4 ST-154 clone, which accounted for 47.5% of all IMD case isolates. The new four-component meningococcal B vaccine appeared to offer adequate coverage against MenB in Atlantic Canada. 相似文献
40.
Jianwei Zhou Frances Jamieson Sharon Dolman Linda MN Hoang Prasad Rawte Raymond SW Tsang 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2012,23(3):e55-e59