全文获取类型
收费全文 | 22389篇 |
免费 | 1342篇 |
国内免费 | 41篇 |
专业分类
耳鼻咽喉 | 150篇 |
儿科学 | 702篇 |
妇产科学 | 735篇 |
基础医学 | 2803篇 |
口腔科学 | 305篇 |
临床医学 | 3615篇 |
内科学 | 3736篇 |
皮肤病学 | 203篇 |
神经病学 | 2334篇 |
特种医学 | 400篇 |
外科学 | 1982篇 |
综合类 | 257篇 |
一般理论 | 32篇 |
预防医学 | 3347篇 |
眼科学 | 325篇 |
药学 | 1291篇 |
中国医学 | 23篇 |
肿瘤学 | 1532篇 |
出版年
2024年 | 15篇 |
2023年 | 152篇 |
2022年 | 228篇 |
2021年 | 418篇 |
2020年 | 289篇 |
2019年 | 442篇 |
2018年 | 544篇 |
2017年 | 409篇 |
2016年 | 458篇 |
2015年 | 549篇 |
2014年 | 753篇 |
2013年 | 1127篇 |
2012年 | 1657篇 |
2011年 | 1805篇 |
2010年 | 941篇 |
2009年 | 844篇 |
2008年 | 1541篇 |
2007年 | 1675篇 |
2006年 | 1559篇 |
2005年 | 1545篇 |
2004年 | 1544篇 |
2003年 | 1403篇 |
2002年 | 1392篇 |
2001年 | 217篇 |
2000年 | 138篇 |
1999年 | 173篇 |
1998年 | 260篇 |
1997年 | 223篇 |
1996年 | 157篇 |
1995年 | 175篇 |
1994年 | 156篇 |
1993年 | 118篇 |
1992年 | 101篇 |
1991年 | 77篇 |
1990年 | 54篇 |
1989年 | 59篇 |
1988年 | 55篇 |
1987年 | 54篇 |
1986年 | 35篇 |
1985年 | 60篇 |
1984年 | 54篇 |
1983年 | 48篇 |
1982年 | 59篇 |
1981年 | 54篇 |
1980年 | 32篇 |
1979年 | 19篇 |
1978年 | 16篇 |
1977年 | 14篇 |
1976年 | 8篇 |
1974年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
Pankaj K Singhal Gregory Spiegel Deborah Driscoll Kunle Odunsi Shashikant Lele Kerry J Rodabaugh 《International journal of gynecological pathology》2005,24(1):62-66
This study was designed to investigate the expression of cyclooxygenase (COX)-2 in ovarian serous tumors (benign, borderline tumors, and carcinomas) and primary peritoneal serous carcinomas. Cases diagnosed between 1995 and 2001 were reviewed; 47 benign tumors, 6 borderline tumors, and 39 carcinomas were examined, as well as 12 normal ovaries that served as controls. Blocks were stained with anti COX-2 polyclonal antibody and staining was graded qualitatively. The staining intensity was assessed as weak (score of 1), moderate (score of 2), or strong (score of 3). Normal ovarian and tubal epithelium, inclusion cysts, benign serous tumors, and borderline tumors had a uniform score 3 staining pattern. Serous ovarian carcinomas had variable staining scores, tending to correlate with the level of tumor differentiation. Well-differentiated carcinomas had more intense COX-2 staining than poorly differentiated carcinomas, which had only weak COX-2 staining. The degree of COX-2 staining was not significantly related to overall survival. In conclusion, COX-2 expression is present in serous tumors, including benign tumors, borderline tumors, and carcinomas. Similar to the findings in other neoplasms, COX-2 expression is strongest in well-differentiated tumors and is much less evident in those that are poorly differentiated. The clinical utility of these findings is related to the potential role of nonsteroidal anti-inflammatory drugs, which are COX-2 inhibitors, in treating and/or preventing some forms of ovarian carcinoma. 相似文献
82.
Vijay A Mittal Shivali Dhruv Kevin D Tessner Deborah J Walder Elaine F Walker 《Neuropsychopharmacology》2007,61(10):1179-1186
BACKGROUND: Evidence suggests that prenatal insult may play a role in the etiology of psychotic disorders. Minor physical anomalies (MPA) are an indicator of abnormal fetal development and are elevated in individuals at genetic and behavioral risk for psychosis. Yet, there has been little empirical research on the relationships between MPAs and other neurobiological risk indicators. We hypothesized that the frequency of MPAs (an external marker of prenatal central nervous system [CNS] disruption) would be associated with two other biomarkers suggestive of disruptions in fetal neurodevelopment: movement abnormalities (an indicator of striatal abnormalities) and heightened cortisol secretion (an indicator of hypothalamic-pituitary-adrenal [HPA]/hippocampal function). METHODS: Participants with schizotypal personality disorder (SPD; n = 39) and both normal (n = 47) and other personality disorders (n = 28) control subjects were administered structured diagnostic interviews and assessed for MPAs, movement abnormalities, and salivary cortisol. RESULTS: Schizotypal personality disorder participants showed significantly greater MPAs and movement abnormalities and higher cortisol than both the normal and other personality disorders groups. Hierarchical linear regression analyses revealed that higher rates of MPAs were linked with greater movement abnormalities and salivary cortisol. CONCLUSIONS: The findings suggest that MPAs serve as a marker of neurodevelopmental abnormalities that affect striatal and hippocampal regions. 相似文献
83.
84.
85.
Melissa Gallagher-Smith Josephine Kim Rasha Al-Bawardy Deborah Josko 《Clinical laboratory science》2004,17(1):35-39
Francisella tularensis, the causative agent of tularemia, is a highly infectious gram-negative coccobacillus. Due to its high infectivity it is of major concern to public health officials as a possible biological weapon. Although accidental exposure can occur through arthropod bites, handling infected animals, or breathing in aerosols, cases are usually isolated and contained. In the event of an intentional exposure such as in a bioterrorist attack, inhalation of aerosols can result in devastating consequences with much causality. Although a vaccine is available, sufficient quantities may not be readily accessible in an actual attack. Therefore, it is very important for both medical professionals and public health officials to be prepared to contain and control the situation should it actually occur. 相似文献
86.
Deepali Kumar Dean Erdman Shaf Keshavjee Teresa Peret Raymond Tellier Denis Hadjiliadis Grant Johnson Melissa Ayers Deborah Siegal Atul Humar 《American journal of transplantation》2005,5(8):2031-2036
Community-acquired viral respiratory tract infections (RTI) in lung transplant recipients may have a high rate of progression to pneumonia and can be a trigger for immunologically mediated detrimental effects on lung function. A cohort of 100 patients was enrolled from 2001 to 2003 in which 50 patients had clinically diagnosed viral RTI and 50 were asymptomatic. All patients had nasopharyngeal and throat swabs taken for respiratory virus antigen detection, culture and RT-PCR. All patients had pulmonary function tests at regular intervals for 12 months. Rates of rejection, decline in forced expiratory volume (L) in 1 s (FEV-1) and bacterial and fungal superinfection were compared at the 3-month primary endpoint. In the 50 patients with RTI, a microbial etiology was identified in 33 of 50 (66%) and included rhinovirus (9), coronavirus (8), RSV (6), influenza A (5), parainfluenza (4) and human metapneumovirus (1). During the 3-month primary endpoint, 8 of 50 (16%) RTI patients had acute rejection versus 0 of 50 non-RTI patients (p=0.006). The number of patients experiencing a 20% or more decline in FEV-1 by 3 months was 9 of 50 (18%) RTI versus 0 of 50 non-RTI (0%) (p=0.003). In six of these nine patients, the decline in FEV-1 was sustained over a 1-year period consistent with bronchiolitis obliterans syndrome (BOS). Community-acquired respiratory viruses may be associated with the development of acute rejection and BOS. 相似文献
87.
Effects of gastric bypass procedures on bone mineral density,calcium, parathyroid hormone,and vitamin d 总被引:2,自引:0,他引:2
Jason M. Johnson James W. Maher Isaac Samuel Deborah Heitshusen Cornelius Doherty Robert W. Downs 《Journal of gastrointestinal surgery》2005,9(8):1106-1111
Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data
on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals
after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic
preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had
or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by
9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n =
14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year,
by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the
operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS)
by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS)
and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively
(25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the
first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the
first year.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation). 相似文献
88.
In this observational study, we sought to assess the usefulness of pH values from residuals in intensive care unit (ICU) patients with small-bore feeding tubes. A review of the literature demonstrated that most critically ill patients were excluded in previous studies on gastric pH testing, suggesting that pH testing in critical care is not warranted. Our results demonstrated that 21% of intestinal testing and 64% of gastric testing yielded potential misinformation to the bedside nurse with regards to possible tube location. In conclusion, pH testing for small-bore tube placement and maintenance was not deemed meaningful in our critical care unit. 相似文献
89.
90.
Deborah Miller Dina Macdonald Ken Kolnacki Teresa Simek 《Nephrology nursing journal》2004,31(3):287-94; quiz 295-6
An important treatment goal for pediatric nephrology caregivers is the optimization of a child's capacity for normal growth and development. However, the physiologic and metabolic derangements associated with chronic kidney disease (CKD) significantly alter these processes, creating important challenges in the care of affected children. Evidence-based clinical practice guidelines support early recognition and treatment of CKD-related complications to improve growth and development and, ultimately, quality of life for children with this chronic condition. 相似文献