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BACKGROUND: Endotracheal intubation and mechanical ventilation are major components of routine intensive care for very low birth weight newborns and sick full-term newborns. These procedures are associated with physiologic, biochemical, and clinical responses indicating pain and stress in the newborn. Most neonates receive some form of analgesia and sedation during mechanical ventilation, although there are marked variations in clinical practice. Clinical guidelines for pharmacologic analgesia and sedation in newborns based on robust scientific data are lacking, as are measures of clinical efficacy. OBJECTIVE: This article represents a preliminary attempt to develop a scientific rationale for analgesia sedation in mechanically ventilated newborns based on a systematic analysis of published clinical trials. METHODS: The current literature was reviewed with regard to the use of opioids (fentanyl, morphine, diamorphine), sedative-hypnotics (midazolam), nonsteroidal anti-inflammatory drugs (ibuprofen, indomethacin), and acetaminophen in ventilated neonates. Original meta-analyses were conducted that collated the data from randomized clinical comparisons of morphine or fentanyl with placebo, or morphine with fentanyl. RESULTS: The results of randomized trials comparing fentanyl, morphine, or midazolam with placebo, and fentanyl with morphine were inconclusive because of small sample sizes. Meta-analyses of the randomized controlled trials indicated that morphine and fentanyl can reduce behavioral and physiologic measures of pain and stress in mechanically ventilated preterm neonates but may prolong the duration of ventilation or produce other adverse effects. Randomized trials of midazolam compared with placebo reported significant adverse effects (P < 0.05) and no apparent clinical benefit; the findings of a meta-analysis suggest that there are insufficient data to justify use of IV midazolam for sedation in ventilated neonates. CONCLUSIONS: Despite ongoing research in this area, huge gaps in our knowledge remain. Well-designed and adequately powered clinical trials are needed to establish the safety, efficacy, and short- and long-term outcomes of analgesia and sedation in the mechanically ventilated newborn.  相似文献   
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The pharmacological properties of the alpha(2)-adrenergic receptors regulating the release of norepinephrine were investigated in human neocortex. Slices were preincubated with [(3)H]norepinephrine, superfused under blockade of transmitter reuptake, and stimulated electrically. First, the autoinhibitory circuit of [(3)H]norepinephrine release was analyzed quantitatively by estimation of the K(d) of norepinephrine at the alpha(2)-autoreceptor (10(-7.99) M), the concentration of the endogenous transmitter causing this autoinhibition at a stimulation frequency of 3 Hz (10(-7.61) M), and the maximum inhibition obtainable through the autoreceptor (83%). Second, antagonist pK(b) values of nine antagonists were determined by using their pEC(50) values (negative logarithms of antagonist concentrations that increased the electrically evoked overflow of tritium by 50%) against the release-inhibiting effect of the endogenous transmitter. When compared with binding or functional data from the literature, the pK(b) values correlated best with the antagonist affinities at alpha(2A) binding sites. In contrast, the correlations with alpha(2B), alpha(2C), and alpha(2D) sites were not as good. It is concluded that in human neocortex prejunctional autoreceptors are alpha(2A).  相似文献   
116.

Background

Papillary muscle rupture (PMR) is a rare complication of a myocardial infarction. The aim of this study was to review our results of mitral valve surgery for acute PMR.

Methods

Data from patients undergoing emergent mitral valve surgery for acute PMR between 2011 and 2017 at our institution were reviewed. Outcomes included operative morbidity and mortality, mitral valve reoperation, and hospital readmission.

Results

A total of 2479 patients underwent mitral valve surgery during the study period including 24 (1.0%) for PMR. Mean age was 62 years, and two (8.3%) patients had prior open‐heart surgery. Overall Society of Thoracic Surgeons predicted risk of mortality was 17.5%. Operative mortality was 12.5% (n = 3) with an observed‐to‐expected mortality ratio of 0.71. There were no strokes, and new onset dialysis was required in two (8.3%) patients. Mean follow‐up was 2.40 ± 1.96 years. Three‐year mortality, mitral valve reoperation, and readmission rates were 21.1%, 5.0%, and 45.4%.

Conclusions

Expeditious operative intervention for PMR can be associated with acceptable operative and longer‐term outcomes.  相似文献   
117.
BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) has been used in patients to increase the level of circulating hematopoietic progenitors. Although G-CSF has been administered to some healthy individuals, the kinetics of mobilization of peripheral blood stem cells (PBSCs), the optimum dose schedule and the incidence and nature of adverse reactions in normal individuals are not completely defined. STUDY DESIGN AND METHODS: Normal individuals (n = 102) who received G- CSF for 5 or 10 days at doses of 2, 5, 7.5, or 10 micrograms per kg per day were studied. The subjects were observed for symptoms and physical changes, and blood samples were obtained for a variety of laboratory tests. After 5 or 10 days of G-CSF treatment, PBSCs were collected by apheresis and analyzed. RESULTS: Overall, 89 percent of the individuals completed the 5-day treatment protocol and 88 percent completed the 10- day protocol without modification of the dose of G-CSF administered. Ninety percent of donors experienced some side effect of G-CSF. The most frequent effects noted were bone pain (83%), headache (39%), body aches (23%), fatigue (14%), and nausea and/or vomiting (12%). The dose of G-CSF administered directly affected the proportion of people with bone pain (p = 0.025) or body aches (p = 0.045) or who were feeling hot or having night sweats (p = 0.02) or taking analgesics (p = 0.01). With the 5-day dose schedule, several changes in serum chemistries occurred, including increases in alkaline phosphatase (p = 0.001), alanine aminotransferase (p = 0.0013), lactate dehydrogenase (p = 0.0001), and sodium (p = 0.0001). Decreases occurred in glucose (p = 0.045), potassium (p = 0.0004), bilirubin (p = 0.001), and blood urea nitrogen (p = 0.0017). In donors who received G-CSF for 5 days, the absolute neutrophil count was increased after one G-CSF dose, and it reached a maximum on Day 6, as did the number of CD34+ cells (64.6 +/? 55.9 × 10(6) cells/L). In those same donors, the platelet count after apheresis on Day 6 was 32 +/? 13 percent lower than pretreatment values (250 +/? 42 × 10(9) cells/L). In donors receiving G-CSF for 10 days, the neutrophil count reached a maximum on Day 8, but the number of CD34+ cells peaked on Day 6 (58.3 +/? 52.1 × 10(5) cells/L) and then declined. The platelet count decreased from pretreatment values by 28 +/? 12 percent prior to apheresis on Day 11. When individuals were treated for 5 days with G-CSF, the quantity of CD34+ cells collected was directly related to the G-CSF dose. When 5 micrograms per kg per day was given, 2.80 +/? 1.81 × 10(8) cells were collected, compared with collection of 4.67 +/? 3.11 × 10(8) cells when 10 micrograms per kg per day was given (p = 0.04). More important, PBSCs collected after 10 days of G-CSF administration (5 micrograms/kg/day) had significantly fewer CD34+ cells (0.82 +/? 0.37 × 10(8) cells, p = 0.01) than did PBSCs collected after 5 days of G-CSF (5 micrograms/kg/day). CONCLUSION: Most normal donors receiving G-CSF experience side effects, but these are mild to moderate in degree. Some alterations in blood chemistries occur, but none were clinically serious. Because of the symptoms associated with G-CSF, these individuals must be monitored closely. The treatment of normal donors with G-CSF for more than 5 days significantly decreased the number of circulating CD34+ cells and the quantity collected by apheresis.  相似文献   
118.
目的:观察对胃溃疡复发有较好疗效的健胃愈疡颗粒对溃疡黏膜乳腺癌相关肽和血小板活化因子表达的影响,分析其可能的作用机制。方法:实验于2005-07/2006-07在湘雅医院中心实验室完成。SD大鼠110只,雌雄各半,随机抽签法分为5组,即正常对照组、假手术组、雷尼替丁组、健胃愈疡组,各20只;模型组30只。以Okabe改良法复制大鼠实验性胃溃疡,假手术组仅以生理盐水代替乙酸注入玻管内。造模后24h,雷尼替丁组、健胃愈疡组大鼠分别灌服盐酸雷尼替丁和健胃愈疡颗粒(药物组成为:柴胡、党参、白芍、延胡索、白芨、珍珠层粉、青黛、甘草,湖南湘雅制药有限公司生产)药液10mL/kg,分别相当于2.70,1.62g/kg,1次/d。假手术组、模型组灌服蒸馏水10mL/kg。10d后各组中随机取出10只大鼠剖腹取胃(处死前大鼠禁食24h),90d时将模型组20只大鼠再分为模型复发组和模型非复发组,各10只;除正常对照组、假手术组、模型非复发组大鼠腹腔内注射生理盐水外,其余各组大鼠腹腔内注射白细胞介素1,1μg/kg;在注射48h,大鼠禁食24h后,剖腹取胃。观察其对胃溃疡大鼠胃黏膜氨基己糖及磷脂含量、溃疡指数和胃黏膜血流的影响,并用RT-PCR观察乳癌相关肽乳癌相关肽和血小板活化因子表达的变化。结果:实验动物110只,全部进入结果分析。①模型组10,92d胃黏膜血流均低于正常对照组(P<0.01);健胃愈疡组同期胃黏膜血流均高于模型组(P<0.01)。②健胃愈疡组和雷尼替丁组10d溃疡指数均低于模型组(P<0.01,P<0.05);模型复发组、健胃愈疡组和雷尼替丁组92d溃疡指数均高于模型组(P<0.01);健胃愈疡组10,92d溃疡指数及复发率均低于雷尼替丁组(P<0.05,P<0.01)。③模型组10,92d氨基己糖和磷脂含量均低于正常对照组(P<0.01)。健胃愈疡组10,92d氨基己糖和磷脂含量均高于模型组和雷尼替丁组(P<0.01)。溃疡指数与氨基已糖、磷脂含量呈负相关(r=-0.957,-0.960,P<0.01)。④健胃愈疡组和雷尼替丁组10d乳癌相关肽mRNA表达较正常组和假手术组提高,血小板活化因子mRNA的表达下调(P<0.01),健胃愈疡组两指标表达变化较雷尼替丁组显著(P<0.01);模型复发组、健胃愈疡组和雷尼替丁组92d乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异无显著性意义(P>0.05);模型组乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异有显著性意义(P<0.01)。结论:健胃愈疡颗粒可提高乳癌相关肽mRNA及下调血小板活化因子mRNA的表达,影响胃黏膜氨基己糖及磷脂含量,可能是其促进溃疡愈合的机制之一。  相似文献   
119.
This study describes an evaluation of a psycho-educational intervention for family caregivers of patients dying of cancer at home. In a randomized controlled trial, participants (n = 106) received standard home-based palliative care services (n = 52) or these services plus the new intervention (n = 54). Data were collected at three time points: upon commencement of home-based palliative care (Time 1), five weeks later (Time 2), and then eight weeks following patient death (Time 3). No intervention effects were identified with respect to preparedness to care, self-efficacy, competence, and anxiety. However, participants who received the intervention reported a significantly more positive caregiver experience than those who received standard care at both Times 2 and 3. The findings indicate that it is possible to increase caregiver rewards despite being immersed in challenging circumstances that often yield considerable negative psychosocial sequelae. Furthermore, it is feasible for health professionals to discuss emotive topics, such as impending death, with caregivers without adverse effects.  相似文献   
120.
This article reports on a retrospective study of the provision of 'after-hours' telephone support by a community palliative care service during 1996 and 1997. Calls received outside of normal office hours were triaged through an inpatient hospice unit located in the same building as the community team. During the study period, 629 patient or carer calls were received, predominantly between 5pm and 11 pm. The main reasons cited for using the after-hours service were medication queries, pain, seeking advice from the nurse and anxiety. The triage nurse successfully handled 30% of the calls. The remaining 70% of calls were transferred to the on-call community palliative care nurse, resulting in 251 home visits. Visits were not predicted by call reason, patient living arrangements, diagnosis or clinical problems; the patient being close to death or having died was a predominant reason for visiting. It was found, however, that call outcomes could be partly predicted by the identity of the triage nurse. It is argued that the findings of this study raise important issues related to the provision of after-hours palliative care and the training of staff providing triage of calls from patients and families at home.  相似文献   
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