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   644篇
  免费   49篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   32篇
妇产科学   7篇
基础医学   87篇
口腔科学   17篇
临床医学   89篇
内科学   125篇
皮肤病学   9篇
神经病学   28篇
特种医学   12篇
外科学   63篇
综合类   17篇
预防医学   49篇
眼科学   39篇
药学   72篇
中国医学   6篇
肿瘤学   40篇
  2023年   7篇
  2022年   16篇
  2021年   35篇
  2020年   14篇
  2019年   14篇
  2018年   23篇
  2017年   12篇
  2016年   17篇
  2015年   39篇
  2014年   19篇
  2013年   34篇
  2012年   37篇
  2011年   41篇
  2010年   22篇
  2009年   20篇
  2008年   23篇
  2007年   44篇
  2006年   37篇
  2005年   32篇
  2004年   51篇
  2003年   29篇
  2002年   32篇
  2001年   8篇
  2000年   8篇
  1999年   3篇
  1994年   4篇
  1993年   2篇
  1992年   8篇
  1991年   5篇
  1990年   3篇
  1989年   5篇
  1988年   5篇
  1984年   2篇
  1983年   4篇
  1982年   1篇
  1981年   1篇
  1979年   5篇
  1978年   5篇
  1977年   1篇
  1976年   4篇
  1975年   4篇
  1974年   4篇
  1971年   2篇
  1968年   1篇
  1963年   1篇
  1947年   1篇
  1940年   1篇
  1935年   1篇
  1934年   2篇
  1933年   1篇
排序方式: 共有695条查询结果,搜索用时 0 毫秒
101.
The aim of this study was to study the effectiveness of the Swenerton score in assessing extent of disease as an independent prognostic and predictive factor in patients with metastatic breast cancer (MBC) who receive high-dose chemotherapy (HDCT) with autologous hematopoietic stem cell transplant (AHSCT). Two-hundred thirty-two patients with MBC underwent HDCT. Extent of disease was assessed quantitatively using the Swenerton score. A retrospective analysis was performed using Cox proportional hazards regression and logistic regression models. One hundred three (44%) patients had a complete response (CR) after HDCT. Bone marrow as source of hematopoietic stem cells, hormone-receptor-negative status, and visceral involvement correlated with both worse overall survival (OS) and progression-free survival (PFS). Short disease-free interval, multiple sites of metastatic disease, and less than 50% reduction in the Swenerton Score during induction chemotherapy correlated with worse OS. Patients in CR at the time of HDCT had better PFS than patients in partial response, stable disease, or progressive disease. Fifty-six patients who underwent conversion to CR after HDCT had a similar median OS (not reached v 74 months; P =.51) and PFS duration (22 v 44 months; P =.15) as patients who received HDCT after a CR to standard-dose chemotherapy (SDCT). Conversion to CR was predicted by a >/=50% reduction in the Swenerton score during SDCT (odds ratio [OR] 3.32, P <.01) and soft-tissue disease (OR 4.08, P <.01). The presence of multiple metastatic sites predicted decreased probability of conversion to CR (OR 0.34, P <.01). The Swenerton score provides a thorough estimate of disease extent, and reduction of Swenerton score by SDCT is potentially useful for selecting the optimal candidates for HDCT trials who may achieve long-term disease control.  相似文献   
102.
103.
Objectives To compare a new scoring system for multibacillary (MB) leprosy relapses, which combines time factor, risk factors and clinical presentation at relapse, to WHO criteria. Methods Data were collected on all relapses diagnosed between 1998 and 2004 at the Marie‐Adelaide‐Centre in Karachi, Pakistan, including case histories, clinical manifestations, follow‐up, bacterial indices, treatment and contacts. For the diagnosis of MB relapses a simple scoring system was developed and validated on a data‐set of mouse foot pads (MFP)‐confirmed relapses (Leprosy Reviews, 76 , 2005, 241). Its sensitivity was further evaluated in the Karachi relapse cohort. The P‐value was calculated with McNemar’s test with continuity correction. Results The new scoring system that combines time factor, risk factors and clinical presentation at relapse had a higher sensitivity in MFP‐confirmed relapses than the WHO‐criteria (95%vs. 65%, P < 0.01). The sensitivity of the scoring system was also significantly higher than the WHO criteria in the 57 cases of MB‐relapses diagnosed in Karachi (72%vs. 54%, P < 0.05). Conclusions This new simple scoring system for diagnosing MB‐relapses in leprosy should be further validated in a prospective study to confirm its superior sensitivity and to evaluate the specificity of these criteria by using MFP‐confirmation for patients presenting with signs of activity after treatment.  相似文献   
104.
Evidence regarding validity of self‐reported family history of cancer (FHC) has been reviewed only for breast, colorectal, prostate, ovarian, endometrial and uterine cancer. We aimed to systematically review studies assessing validity of self‐reported family history for the remaining cancer sites. We searched the Medline database for relevant studies published by January 2016. We extracted information on the study design and the positive predictive value (PPV) of self‐reported FHC, defined as the proportion of reported cancer diagnoses among relatives that was confirmed by a reference standard (as a measure of over‐reporting). We also extracted information on sensitivity of self‐reported FHC (as a measure of underreporting). Overall, 21 studies were included that provided information on the PPV of self‐reported FHC for relevant cancers and four studies also provided information on sensitivity. The PPV was highest (mostly >70%) for pancreatic, lung, thyroid and urinary system cancers and for leukemia and lymphoma, while it was lowest for stomach and liver cancer. Sensitivity was highest (>70%) for pancreatic cancer, lung cancer, brain cancer, melanoma, leukemia and lymphoma. For several cancers, sample sizes were low and the number of studies limited, particularly regarding sensitivity of self‐reported FHC. In conclusion, for some cancers (e.g., pancreatic cancer, lung cancer, leukemia, lymphoma) self‐reported FHC can be considered sufficiently valid to be useful, for example, in preventive counseling. For several cancers, it is not sufficiently studied or the pattern is inconsistent. This needs to be taken into account when using self‐reported information about FHC in clinical practice or epidemiological research.  相似文献   
105.
The Genitourinary (GU) Medicine Service was transferred from the Home Office to the NHS from April 2006 at this female prison to give prisoners access to the same quality of health care as the general public. Medline search showed no published data on the prevalence of sexually transmitted infections (STIs) among female prisoners in the UK. The main aim was to develop a one stop sexual health shop and to determine the prevalence and risk factors for STIs, to determine the uptake rate for HIV testing, hepatitis B vaccination and cervical cytology along with requests for usage of contraceptive services. Challenges were met when introducing change to bring the services in line with the local GU medicine clinic. Review of the service at one year along with retrospective case note review from May 2006 to August 2007 was done. Of the 545 new patients seen, history of substance abuse, IVDU, sexual abuse, sex worker and past history of hepatitis C virus and chlamydia were 86%, 41%,12%, 6%, 17% and 24% respectively.The uptake rate for both STI screen and blood-borne viruses (BBVs) testing was high at 87% and 69.3% respectively. STI was diagnosed in 19.6%. Prevalence rates were: Trichomonas vaginalis (TV) 8.2%, chlamydia 5.3%, gonorrhoea 0.2%, genital warts 5.3%, HIV 0.8%, hepatitis C virus 12% and hepatitis B virus 11%. The uptake rate for 1(st) dose hepatitis B vaccination and cervical cytology were 70% and 92% respectively, 36 accessed contraceptive services. Provision of one stop shop in a female prison is feasible and practical. STIs, particularly TV, and BBVs prevalence is high among the female inmates. Prevention methods targeting this population needs to be intensified.  相似文献   
106.
Pesticides are highly toxic substances. Their toxicity may not be absolutely specific to the target organisms but can adversely affect different processes in the non-target host plants. In the present study, the effect of over application of four commonly used pesticides (emamectin benzoate, alpha-cypermethrin, lambda-cyhalothrin and imidacloprid) was evaluated on the germination, seedling vigor and photosynthetic pigments in tomato. The obtained results revealed that seed germination was decreased by the pesticides and this effect was more prominent at early stages of exposure. All the tested pesticides reduced the growth of tomato when applied in higher concentration than the recommended dose, but at lower doses the pesticides had some stimulatory effects on growth as compared to the control. A similar effect of pesticides was observed on the photosynthetic pigments, i.e. a decrease in pigments concentrations was caused at higher doses but an increase was observed at lower doses of pesticides. The calculation of EC50 values for different parameters revealed the lowest EC50 values for emamectin (ranged as 51–181 mg/L) followed by alpha-cypermethrin (191.74–374.39), lambda-cyhalothrin (102.43–354.28) and imidacloprid (430.29–1979.66 mg/L). A comparison of the obtained EC50 values for different parameters of tomato with the recommended doses revealed that over application of these pesticides can be harmful to tomato crop. In a few cases these pesticides were found toxic even at the recommended doses. However, a field based study in this regard should be conducted to further verify these results.  相似文献   
107.
Severe Acute Malnutrition (SAM) is a serious public health problem in many low- and middle-income countries (LMICs). Therapeutic programs are often considered the most effective solution to this problem. However, multiple social and structural factors challenge the social inclusion, sustainability, and effectiveness of such programs. In this article, we aim to explore how poor and remote households face structural inequities and social exclusion in accessing nutrition-specific programs in Pakistan. The study specifically highlights significant reasons for the low coverage of the Community Management of Acute Malnutrition (CMAM) program in one of the most marginalized districts of south Punjab. Qualitative data are collected using in-depth interviews and FGDs with mothers and health and nutrition officials. The study reveals that mothers’ access to the program is restricted by multiple structural, logistical, social, and behavioral causes. At the district level, certain populations are served, while illiterate, and poor mothers with lower cultural capital from rural and remote areas are neglected. The lack of funding for nutrition causes the deprioritization of nutrition by the health bureaucracy. The subsequent work burden on Lady Health Workers (LHWs) and the lack of proper training of field staff impact the screening of SAM cases. Moreover, medical corruption in the distribution of therapeutic food, long distances, traveling or staying difficulties, the lack of social capital, and the stigmatization of mothers are other prominent difficulties. The study concludes that nutrition governance in Pakistan must address these critical challenges so that optimal therapeutic coverage can be achieved.  相似文献   
108.
Clear‐cell carcinoma (CCC) is an uncommon malignant tumor of minor salivary glands. It characteristically has a low‐grade morphology and a favorable outcome by most reports. An EWSR1‐ATF1 fusion can be detected in the majority of cases. We present a rare case of CCC, which had an aggressive course with the development of cutaneous metastases. Practicing dermatopathologists should be aware of this tumor given its low‐grade appearance and histopathologic resemblance to other primary cutaneous adnexal and metastatic neoplasms.  相似文献   
109.
110.
Cutaneous leishmaniasis (CL) has increased remarkably in Iran and has expanded into new areas. The present study aimed to assess the emerging CL outbreak in southeastern Iran using high resolution melting‐polymerase chain reaction (HRM‐PCR) and phylogenetic analysis using the 7SL RNA gene marker. A cross‐sectional and analytical survey was conducted during a house‐to‐house census of 11,021 inhabitants in Narmashir County in southeastern Iran in 2016. The cases were detected by direct smear microscopic examination and sequencing and were characterized using the 7SL RNA gene. All age groups and sexes were equally affected. Most were single lesions (70.7%). The hands (55.2%) and face (37.9%) were the main sites of involvement. The disease was more common among illiterate persons. Sequencing and HRM‐PCR revealed that Leishmania tropica (accession no. MH632168 Qale‐Shahid) was the principal causative agent of anthroponotic CL (ACL) in new areas of expansion. This is the first emergence of ACL in rural areas of Narmashir County. Based on the molecular data, the causative parasite species confirmed to be L. tropica. Sequencing and phylogenetic analysis indicated that a single clone of the organism derived from a single source has spread into the affected villages. Construction of a main road, population movement and recent urbanization in the area are likely the major factors associated with the establishment of this new outbreak. This study was essential to enable the planning of effective therapeutic and prophylactic measures to control the disease.  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