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   3155篇
  免费   250篇
  国内免费   24篇
耳鼻咽喉   48篇
儿科学   72篇
妇产科学   140篇
基础医学   523篇
口腔科学   45篇
临床医学   386篇
内科学   663篇
皮肤病学   113篇
神经病学   254篇
特种医学   95篇
外科学   286篇
综合类   67篇
预防医学   159篇
眼科学   73篇
药学   246篇
中国医学   17篇
肿瘤学   242篇
  2023年   19篇
  2022年   32篇
  2021年   90篇
  2020年   58篇
  2019年   84篇
  2018年   94篇
  2017年   89篇
  2016年   80篇
  2015年   120篇
  2014年   147篇
  2013年   192篇
  2012年   259篇
  2011年   273篇
  2010年   177篇
  2009年   150篇
  2008年   223篇
  2007年   202篇
  2006年   179篇
  2005年   153篇
  2004年   131篇
  2003年   114篇
  2002年   93篇
  2001年   72篇
  2000年   41篇
  1999年   63篇
  1998年   28篇
  1997年   19篇
  1996年   13篇
  1995年   6篇
  1994年   15篇
  1993年   6篇
  1992年   12篇
  1991年   21篇
  1990年   20篇
  1989年   15篇
  1988年   27篇
  1987年   16篇
  1986年   16篇
  1985年   10篇
  1984年   16篇
  1983年   4篇
  1981年   5篇
  1980年   5篇
  1979年   8篇
  1978年   4篇
  1977年   4篇
  1975年   3篇
  1974年   5篇
  1971年   4篇
  1969年   2篇
排序方式: 共有3429条查询结果,搜索用时 0 毫秒
101.
Previous studies have described racial and socioeconomic disparities in the treatment of infertility. Patient factors such as attitudes and awareness may be contributing factors. Since primary care is often the setting that serves as an entry into other areas of medicine, we sought to evaluate men's attitudes and awareness of male infertility in the primary care setting. To do this, we performed a cross-sectional survey of men's attitudes toward men's health issues in 210 men from two primary care clinic waiting rooms in Atlanta, Georgia. The survey was self-administered with closed-ended question items and was approximately 20 min in length. Of the 310 men approached, 210 agreed to participate and returned completed surveys. Overall, 52% of men said they were "very" or "somewhat" familiar with infertility and 25% were familiar with treatments for infertility. Some men had heard of surgery (21%) and medication (35%) as treatments for male infertility. Awareness and familiarity with the condition was greater in high socioeconomic status men (i.e. college graduates or those with income 〉$100 k per year) but did not differ by race on multivariate analysis. Attitudes toward infertility varied by race with non-Caucasian men being more likely to indicate that infertility is a serious condition, to be concerned about infertility, and to believe it decreases a man's quality-of-life. Therefore, a lack of awareness, but not negative attitudes, may contribute to previously-described disparities in the treatment of infertility.  相似文献   
102.
103.
Ouabain, a cardiotonic steroid, was used for the treatment of heart failure and atrial fibrillation and induces cancer cell apoptosis in many human cancer cells including human leukemia cells. However, there are no reports to show the effects on immune responses in a leukemia mouse model. In this study, WEHI‐3 cell generated leukemia mice were developed and treated by oral ouabain at 0, 0.75, 1.5, and 3 mg/kg for 15 days. Results indicated that ouabain did not affect body appearance, but decreased liver and spleen weights, B‐ and T‐cell proliferation at all three doses treatment and increased CD19 cells at 3.0 mg/kg treatment, decreased CD3, CD11b, and Mac‐3 cells levels compared with positive control. Furthermore, ouabain increased the macrophage phagocytosis from peripheral blood mononuclear cell and peritoneal cavity at all three doses treatment and increased NK cell activities. Ouabain restored GOT, GPT and LDH levels in WEHI‐3 leukemia mice in vivo.  相似文献   
104.
105.
Oral squamous cell carcinoma (OSCC) is the fifth common cause of cancer mortality in Taiwan with high incidence and recurrence and needs new therapeutic strategies. In this study, ursolic acid (UA), a triterpenoid, was examined the antitumor potency in OSCC cells. Our results showed that UA inhibited the proliferation of OSCC cells in a dose‐ and time‐dependent manner in both Ca922 and SCC2095 oral cancer cells. UA induced caspase‐dependent apoptosis accompanied with the modulation of various biological biomarkers including downregulating Akt/mTOR/NF‐κB signaling, ERK, and p38. In addition, UA inhibited angiogenesis as evidenced by abrogation of migration/invasion and blocking MMP‐2 secretion in Ca922 cells. Interestingly, UA induced autophagy in OSCC cells, as manifested by LC3B‐II conversion and increased p62 expression and accumulation of autophagosomes. Inhibition by autophagy inhibitor enhanced UA‐mediated apoptosis in Ca922 cells. The experiment provides a rationale for using triterpenoid in the treatment of OSCC.  相似文献   
106.
Patients with immune thrombocytopenia (ITP) may be at increased risk of infection because of the steroids and other immunosuppressive agents used in its treatment. This study aimed to identify events that are associated with infection within 6 months of diagnosis and the impact that infection has on survival. We retrospectively evaluated 239 patients (107 men, 132 women; median age 61 years) diagnosed between January 1997 and August 2011. Every patient received steroid treatment according to the platelet count and the extent of bleeding. Logistic regression analysis was used to identify risk factors associated with the development of infection within 6 months of ITP being diagnosed. Sixty-two patients (25.9 %) developed an infection within 6 months of diagnosis. Multivariate analysis revealed that a lower absolute lymphocyte count (ALC) at diagnosis (<1?×?109/l) was an independent risk factor for infection (P?=?0.039; 95 % confidence interval, 1.033–3.599; odds ratio, 1.928). The time to infection event is significant shorter in those of low ALC, compared with those of higher ALC (P?=?0.032). Furthermore, the 1-year mortality rate after ITP diagnosis was significantly higher in those patients who developed an infection (P?=?0.001). ITP patients with a low absolute lymphocyte count at diagnosis have an increased risk of infection, and those who develop infections have lower 1-year survival.  相似文献   
107.
108.
Delayed diagnosis of hematological malignancies in immunocompetent patients with fever of unknown origin (FUO) remains an exhausting challenge for non-hematologist physicians. This retrospective cohort study aimed to establish a scoring system, “bone marrow (BM) score”, to identify FUO patients who require early bone marrow biopsy (BMB) to diagnose hematological disease.Two cohorts, comprising 85 (training) and 20 (validation) eligible immunocompetent patients, with FUOs diagnosed between January 1, 2006 and July 31, 2013, underwent BMBs and were enrolled in the study. Demographic, laboratory, imaging, diagnostic, and outcome data were collected and retrospectively analyzed. Factors associated with hematological etiologies diagnosed using BMBs in the training cohort were identified and scored according to the relative hazards. These were further validated using the validation cohort.For the training cohort, 29 of 85 (34.1%) patients had hematological etiologies diagnosed using BMB. Seven factors significantly predicted the diagnostic yield of hematological diseases in the BM and were scored, with the 6 points for leucoerythroblastic changes in peripheral blood smears, 5.5 for elevated ferritin level (>1000 ng/mL), 4 for splenomegaly, 2 for thrombocytopenia, 1.5 for each of elevated lactate dehydrogenase levels and anemia, and 1 for neutropenia. When the cut-off value of the scoring system was set to 6, its sensitivity and specificity to diagnose hematological diseases in the BM of immunocompetent FUO patients were 93% and 58%, respectively. For the validation cohort, 7 of 20 (35%) patients had hematological disease, and all had BM scores higher than the cut-off, with the sensitivity and specificity at 100% and 77%, respectively.As immunocompetent FUO patients with hematological disease have poor prognoses, the “BM score” is valuable for non-hematologist physicians to identify immunocompetent FUO patients requiring early BMB.  相似文献   
109.
Precise regulation of bone resorption is critical for skeletal homeostasis. We report a 32‐year‐old man with a panostotic expansile bone disease and a massive hemorrhagic mandibular tumor. Originally from Mexico, he was deaf at birth and became bow‐legged during childhood. There was no family history of skeletal disease. Puberty occurred normally, but during adolescence he experienced difficulty straightening his limbs, sustained multiple fractures, and developed a bony tumor on his chin. By age 18 years, all limbs were misshapen. The mandibular mass grew and protruded from the oral cavity, extending to the level of the lower ribs. Other bony defects included a similar maxillary mass and serpentine limbs. Upon referral at age 27 years, biochemical studies showed serum alkaline phosphatase of 1760 U/L (Nl: 29‐111) and other elevated bone turnover markers. Radiography of the limbs showed medullary expansion and cortical thinning with severe bowing. Although the jaw tumors were initially deemed inoperable, mandibular mass excision and staged partial maxillectomy were eventually performed. Tumor histopathology showed curvilinear trabeculae of woven bone on a background of hypocellular fibrous tissue. Fibrous dysplasia of bone was suspected, but there was no mutation in codon 201 of GNAS in samples from blood or tumor. His clinical and radiographic findings, elevated serum markers, and disorganized bone morphology suggested amplified receptor activator of NF‐κB (RANK) signaling, even though his disorder differed from conditions with known constitutive activation of RANK signaling (eg, familial expansile osteolysis). We found a unique 12‐base pair duplication in the signal peptide of TNFRSF11A, the gene that encodes RANK. No exon or splice site mutations were found in the genes encoding RANK ligand or osteoprotegerin. Alendronate followed by pamidronate therapies substantially decreased his serum alkaline phosphatase activity. This unique patient expands the phenotypes and genetic basis of the mendelian disorders of RANK signaling activation. © 2014 American Society for Bone and Mineral Research.  相似文献   
110.

Objectives

To investigate the characteristics of psychological distress (PD), personality traits, and family support in women with overactive bladder syndrome (OAB), and the effects of antimuscarinic treatment.

Study design

Women with and without OAB (age- and body mass index [BMI]-matched control group) were prospectively enrolled; they recorded bladder diaries, underwent urodynamic studies, and completed PD, personality traits, and filled family support questionnaires before and after antimuscarinic treatment. OAB women underwent treatment with tolterodine or solifenacin for 12 weeks. The control group completed questionnaires.

Main outcome measures

The differences in PD, personality traits, and family support scores between both groups, and the changes after antimuscarinic treatment in OAB women.

Results

Eighty-five women with OAB (tolterodine, n = 42; solifenacin, n = 43) and 65 without OAB completed the studies. Linear regression analysis with age and BMI adjustment revealed: coefficients of OAB were significant (all P < 0.05) for somatic complaints (mean: 0.87 vs. 0.63, coefficient = 0.21), obsessive–compulsive symptoms (0.69 vs. 0.44, coefficient = 0.25), anxiety symptoms (0.42 vs. 0.27, coefficient = 0.14), General Symptom Index (GSI, 0.48 vs. 0.33, coefficient = 0.14), neuroticism (9.23 vs. 5.17, coefficient = 3.73), and extroversion–introversion (13.64 vs. 15.25, coefficient = −1.73). Anxiety symptoms (0.42 vs. 0.36) and GSI (0.48 vs. 0.39) improved after antimuscarinics (all P < 0.05). High Overactive Bladder Symptom Score questionnaire score (coefficient = −0.39), low hostility score (coefficient = 2.11), and high additional symptoms score (coefficient = −1.46) were associated with good therapeutic effect (all P < 0.05).

Conclusions

OAB women experience more PD, neuroticism, and introversion than asymptomatic women, and antimuscarinics could improve PD.  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