全文获取类型
收费全文 | 741篇 |
免费 | 53篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 28篇 |
妇产科学 | 8篇 |
基础医学 | 104篇 |
口腔科学 | 8篇 |
临床医学 | 67篇 |
内科学 | 187篇 |
皮肤病学 | 2篇 |
神经病学 | 40篇 |
特种医学 | 17篇 |
外科学 | 70篇 |
综合类 | 11篇 |
预防医学 | 56篇 |
眼科学 | 16篇 |
药学 | 133篇 |
1篇 | |
中国医学 | 14篇 |
肿瘤学 | 25篇 |
出版年
2024年 | 1篇 |
2023年 | 6篇 |
2022年 | 42篇 |
2021年 | 32篇 |
2020年 | 24篇 |
2019年 | 25篇 |
2018年 | 26篇 |
2017年 | 19篇 |
2016年 | 22篇 |
2015年 | 24篇 |
2014年 | 36篇 |
2013年 | 33篇 |
2012年 | 57篇 |
2011年 | 62篇 |
2010年 | 28篇 |
2009年 | 30篇 |
2008年 | 54篇 |
2007年 | 41篇 |
2006年 | 33篇 |
2005年 | 39篇 |
2004年 | 25篇 |
2003年 | 15篇 |
2002年 | 14篇 |
2001年 | 4篇 |
2000年 | 11篇 |
1999年 | 15篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1995年 | 2篇 |
1992年 | 8篇 |
1991年 | 6篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 9篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1979年 | 4篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1927年 | 1篇 |
排序方式: 共有796条查询结果,搜索用时 15 毫秒
81.
N Selvakumar E Prabhakaran B N Murthy S Sivagamasundari S Vasanthan R Govindaraju M Perumal F Wares L S Chauhan T Santha P R Narayanan 《The international journal of tuberculosis and lung disease》2005,9(3):306-309
SETTING: Designated microscopy centres (DMC) and additional microscopy centres (AMC) performing sputum acid-fast bacilli (AFB) microscopy, the District TB Centre (DTC) and a reference laboratory (RL). OBJECTIVES: To ascertain the feasibility of adopting lot sampling of AFB smears and to assess the performance of MCs employing Senior Tuberculosis Laboratory Supervisors (STLS) with no knowledge about the principles of quality assurance of AFB microscopy and RL-based laboratory technicians with training on quality assurance for blinded checking of AFB smears. METHODS: Slides from MCs were transported to the DTC and the RL; 20 smears per month per MC were selected systematically; 1547 slides from DMCs and 726 from AMCs were checked, respectively, by STLSs at the DTC and by RL laboratory technicians. Discrepancies were resolved by referee. RESULTS: The discrepancy between MC laboratory technicians and STLSs at the DTC was 4.7%, compared to 1% at the RL. The STLSs and RL-based laboratory technicians had 70 and 2 errors, respectively. CONCLUSIONS: Lot sampling of AFB smears is feasible under field conditions. Assessment of MCs was more valid with RL-based technicians trained in principles of quality assurance of sputum AFB microscopy than with STLSs with no such training and working in the field. 相似文献
82.
83.
Adenocarcinoma of the jejunum in association with celiac sprue 总被引:3,自引:0,他引:3
An increased incidence of small bowel lymphoma in patients with long-standing celiac sprue is well documented in the literature. Less common is the association of adenocarcinoma of the small intestine. We report a patient with celiac sprue who initially responded to a gluten-free diet. Eighteen months later, diarrhea, abdominal cramps, and bloating was found to have its origin in partial small bowel obstruction. At laparotomy, two distinct adenocarcinomas of the jejunum were resected. Celiac patients who initially respond to gluten withdrawal and subsequently suffer exacerbation while adhering to strict dietary therapy should be carefully evaluated for evidence of a small bowel malignancy. 相似文献
84.
85.
Evaluation of uroprotective efficacy of amifostine against cyclophosphamide induced hemorrhagic cystitis 总被引:3,自引:0,他引:3
Srivastava A Nair SC Srivastava VM Balamurugan AN Jeyaseelan L Chandy M Gunasekaran S 《Bone marrow transplantation》1999,23(5):463-467
The role of amifostine in the prevention of cyclophosphamide-induced hemorrhagic cystitis (HC) was evaluated in the rat model. Urinary bladders from control rats that received no drugs (group I) were compared with those from rats receiving cyclophosphamide alone at a dose of 150 mg/kg (group II), and two other groups receiving amifostine at 100 mg/kg (group III) and 200 mg/kg (group IV), 15 min prior to cyclophosphamide. Bladders were assessed macroscopically and histologically at 24 h and after 7 days. All the animals that received cyclophosphamide alone developed severe HC. On the basis of the scores of macroscopic and histologic changes, animals that received amifostine showed excellent uroprotection. Only 2/6 rats in group III and 1/6 rats in group IV developed mild HC at 24 h. None of the rats in either of these groups showed any evidence of HC at 7 days. It is concluded that amifostine protects the urothelium against cyclophosphamide-induced HC. 相似文献
86.
Brian?P.?LucasEmail author Arthur?T.?Evans Brendan?M.?Reilly Yuri?V.?Khodakov Kalyani?Perumal Louis?G.?Rohr Joseph?A.?Akamah Tunji?M.?Alausa Christopher?A.?Smith Jeremy?P.?Smith 《Journal of general internal medicine》2004,19(5):402-409
OBJECTIVE: Previous studies have shown that most medical inpatients receive treatment supported by strong evidence (evidence-based treatment),
but they have not assessed whether and how physicians actually use evidence when making their treatment decisions. We investigated
whether physicians would change inpatient treatment if presented with the results of a literature search.
DESIGN: Before-after study.
SETTING: Large public teaching hospital.
PARTICIPANTS: Random sample of 146 inpatients cared for by 33 internal medicine attending physicians.
INTERVENTIONS: After physicians committed to a specific diagnosis and treatment plan, investigators performed standardized literature searches
and provided the search results to the attending physicians.
MEASUREMENTS AND MAIN RESULTS: The primary study outcome was the number of patients whose attending physicians would change treatment due to the literature
searches. These changes were evaluated by blinded peer review. A secondary outcome was the proportion of patients who received
evidence-based treatment before and after the literature searches. Attending physicians changed treatment for 23 (18%) of
130 eligible patients (95% confidence interval, 12% to 24%) as a result of the literature searches. Overall, 86% of patients
(112 of 130) received evidence-based treatments before the searches and 87% (113 of 130) after the searches. Changes were
not related to whether patients were receiving evidence-based treatment before the search (P=.6). Panels of peer reviewers judged the quality of patient care as improved or maintained for 18 (78%) of the 23 patients
with treatment changes.
CONCLUSIONS: Searching the literature could improve the treatment of many medical inpatients, including those already receiving evidence-based
treatment.
Presented at the National Society of General Internal Medicine Meeting, May 2002 (finalist for the Milton W. Hamolsky Award). 相似文献
87.
Larvicidal efficacy of Teknar HP-D, an improved biolarvicidal formulation of Bacillus thuringiensis ssp. israelensis (Bti), against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was determined in the laboratory, and in field the efficacy of the formulation was tested against Cx. quinquefasciatus breeding in cesspits, unused wells and drains. The toxicity of the formulation to Gambusia affinis (larvivorous fish), Notonecta sp. and Diplonychus indicus (water bugs) was also evaluated in the laboratory. Teknar HP-D was field tested at three recommended dosages, 1, 1.5 and 2l/ha, selecting five habitats for each dosage. Another five habitats were kept untreated as controls. Ae. aegypti showed greatest susceptibility to the Bti toxin in the laboratory. In cesspits, all the three dosages caused >80% reduction of pupal recruitment up to day 6 post-treatment, indicating that a weekly application at the lowest would be necessary for sustained control. The residual activity of the formulation was longer in unused wells, causing >80% reduction of pupal recruitment for 17 days from the day of treatment. In controlling pupal recruitment the three dosages produced equal effect. Application of Teknar HP-D at 1 l/ha once in three weeks is therefore recommended to control Cx. quinquefasciatus in unused wells. However, in drains, >80% reduction of pupal recruitment was observed for only 3 days and hence, application of Teknar HP-D at 2 l/ha that caused significantly higher level of reduction twice in a week at 3-day interval is necessary. At dosages from 0.032 to 3.2 mg/l (ppm), Teknar HP-D was non-toxic to Gambusia fish. The two predatory water bugs, Notonecta sp. and Diplonychus indicus that fed on the surviving larvae of Cx. quinquefasciatus exposed to the sub-lethal doses (LC(50) and LC(80)) of Teknar HP-D were safe with out having any mortality. 相似文献
88.
89.
T Santha R Garg R Subramani V Chandrasekaran N Selvakumar R S Sisodia M Perumal S K Sinha R J Singh R Chavan F Ali S K Sarma K M Sharma R D Jagtap T R Frieden L Fabio P R Narayanan 《The international journal of tuberculosis and lung disease》2005,9(1):61-68
SETTING: Governmental health facilities in six districts of India. OBJECTIVE: To estimate the prevalence of cough and to compare the detection of smear-positive tuberculosis (TB) among out-patients with cough of > or =2 or > or =3 weeks. DESIGN: Trained health workers questioned each out-patient for presence of cough. Those with cough > or =2 weeks underwent sputum microscopy. RESULTS: Of 55561 out-patients interviewed, 2210 (4%) had cough > or =2 weeks, of whom 267 had sputum-positive TB, compared to 182/1370 with cough > or =3 weeks. The 31% who did not spontaneously complain of cough were less likely to be sputum-positive than those who did (45/680 [7%] vs. 222/1530 [15%], P < 0.001), but they accounted for 45/267 smear-positive cases. Using cough > or =2 weeks as the screening criterion, the estimated number of smears performed per day at each primary and secondary health care facility was respectively 8 and 19, compared to 5 and 12 using cough > or =3 weeks. CONCLUSION: The detection of smear-positive TB cases can be substantially improved by actively eliciting history of cough from all out-patients, and by changing the screening criterion for performing sputum microscopy among out-patients from cough > or =3 weeks to > or =2 weeks. Before implementing this change nationally, its programmatic feasibility should be assessed. 相似文献
90.
Priya M Miranda Viswanathan Mohan Sekhar Ganthimathy Ranjit M Anjana S Gunasekaran Venkatachalam Thiagarajan Thomas A Churchill Tatsuya Kin AM James Shapiro Jonathan RT Lakey 《Islets》2013,5(5):188-195
The aim of this study was to assess recovery, cell death, and cell composition of post-thaw cultured human islets. Cryopreserved islets were provided by the Clinical Islet Transplant Program, Edmonton, Canada. Islets were processed using media prepared in accordance with Pre-Edmonton and Edmonton protocols. Cryopreserved islets were rapidly thawed and cultured for 24 h, 3 d, 5 d, and 7 d, following which they were processed for histology. Islet quantification, integrity, morphology and tissue turnover were studied via hematoxylin and eosin stained sections. Ultrastructure was studied by electron microscopy and endocrine cell composition by immunohistochemistry. Using the Pre-Edmonton protocol, islet recovery was 50.1% and islet survival was 50% at 24 h while for the Edmonton protocol, the islet recovery was 69.4% (p < 0.001) and islet survival, 50% at ≈2.5 d. With an increasing culture duration although the physical integrity was retained there was an increasing loss of cohesivity both at light microscopic and at ultrastructure level regardless of the protocols used. Percentage islet survival and tissue turnover correlated negatively with culture duration in both protocols. The Edmonton protocol appears to preserve the islets better. However, culture duration adversely affects islet survival and quality, indicating the need for more optimal cryopreservation and culture techniques. 相似文献