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81.
Purpose: Biomarkers may predict neurological prognosis in infants with hypoxic-ischemic encephalopathy (HIE). We evaluated the relationship between serum lactate dehydrogenase (LDH) and brain magnetic resonance imaging (MRI), which predicts neurodevelopmental outcomes, in order to assess whether LDH levels are similarly predictive.

Materials and methods: Medical records were reviewed for infants with HIE and LDH levels were assessed on the first (LDH1) and third (LDH3) days following birth. Receiver operating characteristic curves were obtained in relation to central gray matter hypoxic-ischemic lesions.

Results: Of 92 patients, 52 (56.5%) had hypoxic-ischemic lesions on brain MRI, and 21 of these infants (40.4%) had central gray matter lesions. LDH1 and LDH3 did not differ; however, the percentage change (ΔLDH%) was significantly higher in infants with central gray matter lesions (36.9% versus 6.6%, p?=?0.006). With cutoffs of 187 (IU/L, ΔLDH) and 19.4 (%, ΔLDH%), the sensitivity, specificity, positive predictive value and negative predictive value were 71.4, 69.0, 40.5 and 89.1%, respectively. The relative risk was 5.57 (p?=?0.001).

Conclusion: Changes in serum LDH may be a useful biomarker for predicting future neurodevelopmental prognosis in infants with HIE.  相似文献   
82.
BACKGROUND & AIMS: Studies on the early steps in the life cycle of hepatitis B virus have been hampered by the lack of readily available target cells. In this study, we mapped a defined virus attachment site to primary hepatocytes that is essential for infection. METHODS: We used purified virus particles from human carrier plasma as an inoculum and primary cultures of tupaia hepatocytes as susceptible target cells and studied the inhibitory effect of amino-terminally acylated preS1-derived lipopeptides on infection interference. RESULTS: Infectivity of virus could be blocked efficiently in this system by amino-terminally acylated peptides containing amino acids 2-18 from the preS1 domain. The addition of amino acids 28-48 enhanced the inhibitory capacity, whereas amino acids 49-78 did not contribute to inhibition. Myristoylated preS1 peptides 2-48 bound strongly to tupaia hepatocytes but not to nonhepatic cells or rodent hepatocytes and thereby inhibited infection even at concentrations of 1 nmol/L completely. Particles consisting only of the small hepatitis B surface protein-the active component of current hepatitis B vaccines-did not bind at all to tupaia hepatocytes, but the addition of the preS1 domain to the particles allowed binding. CONCLUSIONS: The preS1 sequence 2-48 mediates attachment of the virus to its target cells, whereas the small surface protein seems to be involved in other steps. These findings indicate that the current subunit hepatitis B vaccines may be improved by the addition of distinct preS1 epitopes. Moreover, preS1 lipopeptides are promising candidates for specific antiviral therapy against hepatitis B infections.  相似文献   
83.
Summary A placebo-controlled, double-blind crossover study was undertaken in 10 normal subjects to examine the effects of arotinolol (10 mg bid), a nonselective beta blocker with alpha-blocking activity, on exercise capacity and hormone levels during exercise after a 2-week treatment period. Maximal oxygen uptake (VO2 max) and blood lactic acid concentration (LA) were measured during progressive exercise testing. An exercise intensity equivalent to 4 mmol/l of LA was used for the constant workload exercise test. Humoral factors were measured after 20 minutes of constant workload exercise. The administration of arotinolol significantly decreased systolic blood pressure and heart rate at rest and during exercise, but diastolic blood pressure did not change. No significant difference was found between arotinolol and placebo with regard to VO2 max and maximal workload. Plasma renin activity (PRA), aldosterone (PAC), and norepinephrine (NE) levels at rest and during exercise did not differ between the two treatments. In contrast, plasma epinephrine (EN) levels at rest and during exercise were significantly greater with arotinolol. Atrial natriuretic peptide (ANP) at rest did not differ between the two treatments. However, exercise caused a significant increase in ANP after arotinolol treatment. These findings suggest that arotinolol decreases blood pressure and heart rate without affecting exercise capacity.  相似文献   
84.
Astrocyte swelling represents the major factor responsible for the brain edema associated with fulminant hepatic failure (FHF). The edema may be of such magnitude as to increase intracranial pressure leading to brain herniation and death. Of the various agents implicated in the generation of astrocyte swelling, ammonia has had the greatest amount of experimental support. This article reviews mechanisms of ammonia neurotoxicity that contribute to astrocyte swelling. These include oxidative stress and the mitochondrial permeability transition (MPT). The involvement of glutamine in the production of cell swelling will be highlighted. Evidence will be provided that glutamine induces oxidative stress as well as the MPT, and that these events are critical in the development of astrocyte swelling in hyperammonemia.  相似文献   
85.
Summary In 5 closely controlled pregnant diabetics (duration of pregnancy 237–266 days) and 5 pregnant non-diabetics (duration of pregnancy 210–278 days) 4-hourly blood samples were taken throughout a 24 h period and analyzed for blood glucose, lactate, pyruvate, 3-hydroxybutyrate and acetoacetate, plasma non-esterified fatty acids (NEFA), glucagon and cortisol. 24 h urine specimen was analyzed for total catecholamines and 4-hydroxy-3-methoxymandelic acid. There were few significant differences in concentrations of metabolites and hormones in the two groups at any time, although the variations about the mean was usually greater in the diabetics. Thus for blood glucose in diabetics, mean value was 4.4 mmol/l, coefficient of variation 43%; in non-diabetics 4.1 mmol/l and 10% respectively. Mean plasma 3-hydroxybutyrate in diabetics was 0.47 mmol/l, coefficient of variation 55%; in non-diabetics 0.44 mmol/l and 37% respectively. Plasma non-esterified fatty acid levels were significantly higher in the diabetics (0.47 mmol/l) than in the non-diabetics (0.26 mmol/l). Coefficients of variation were 46% and 33% respectively. Two conclusions can be drawn; first, when near normal mean values for blood glucose are achieved, other metabolite and hormone levels are also near normal; second, even when the available means for diabetic control, strict diet and insulin-mixtures twice daily, are used at their maximum, metabolism in diabetics is more unstable than in non-diabetics.  相似文献   
86.
Sheppard  M. C.  Burrin  J.  Alberti  K. G. M. M.  Nattrass  M. 《Diabetologia》1983,24(5):333-335
Summary The metabolic response to a standard meal was studied in six Type 2 (non-insulin-dependent) diabetic patients at diagnosis and following 4–6 weeks of dietary treatment. The fall in blood glucose concentration following treatment was accompanied by significant reductions in circulaitng concentrations of lactate, pyruvate, alanine and glycerol. Blood 3-hydroxybutyrate concentrations also fell with treatment.  相似文献   
87.
目的:探讨与分析血清降钙素原、C-反应蛋白及脑脊液乳酸脱氢酶检测在小儿中枢神经系统感染的价值。方法随机选取2010年4月-2014年4月于该院接受治疗的60例中枢神经系统感染患儿作为研究对象,所有患儿均在入院后实施血清降钙素原、C-反应蛋白及脑脊液乳酸脱氢酶检测,评估其诊断价值。结果细菌感染组患儿血清内PCT、CRP及脑脊液LDH浓度水平明显高于病毒感染组,差异有统计学意义(P<0.05)。三者联合检测灵敏度与准确度明显高于单项检测与两项联合检测,差异有统计学意义(P<0.05)。结论三者联合检测可有效提升小儿中枢系统感染的检出率,同时在鉴别病毒性与细菌性感染方面有一定的价值,有利于早期的鉴别诊断及积极治疗。  相似文献   
88.
鉏瑛  杨阳 《淮海医药》2015,(3):240-241
目的:对乳酸左氧氟沙星氯化钠注射液不良反应进行分析研究,做出安全性风险评价。方法对我市2014年收集的12例乳酸左氧氟沙星氯化钠注射液不良反应报告采用回顾性研究方式,用Excel电子表筛选方法,进行统计、分析。结果本资料12例报告中,50岁以上人群所占比例最大,有6例(占50%);男性患者发生药品不良反应的几率明显高于女性;药品不良反应临床表现为全身性损害、皮肤及其附件损害、胃肠道损害(各占33.3%,41.7%,25%);新的严重的药品不良反应2例(占16.7%);好转5例,痊愈7例,无死亡病例。结论乳酸左氧氟沙星氯化钠注射液使用风险在临床中可表现为各种不良反应,不当给药方法和联合用药对该药不良反应的发生可能具有相当大的影响。应严格掌握适应症,加强不良反应监测才能确保乳酸左氧氟沙星氯化钠注射液使用的安全性和有效性。  相似文献   
89.
Malignant melanoma is a highly malignant tumor originating from the melanocytes of the neural crest, which is prone to metastasis and has a poor prognosis. Previous research demonstrated that melanoma inhibitory activity (MIA) and lactate dehydrogenase (LDH) could serve as serum markers in malignant melanoma and indicate prognosis in the Caucasian race. Researchers suspected that both MIA and LDH could prompt the prognosis of malignant melanoma in the Chinese population. This study aimed to investigate the value of MIA and LDH in the prognosis of acral malignant melanoma.From January 1, 2014, to December 31, 2017, in Jiangsu Province, 44 acral malignant melanoma patients with complete data were chosen from the clinic. The LDH levels were extracted from their clinical data, and MIA levels were measured by enzyme-linked immunosorbent assay method. 8 paired advancing samples before and after metastasis were examined. 22 health donors were matched to the patient group. Receiver operating characteristic (ROC) curves of MIA and LDH were drawn to determine acral malignant melanoma tumorigenesis and metastasis and finally got the cut-off value. Cumulative survival was illustrated with the Kaplan-Meier plot, and factors were compared using the Log-rank test.Compared with age-matched healthy donors, MIA was significantly high in patients (P < .001). Moreover, serum MIA was significantly higher in III-IV stage patients than I-II stage patients (P < .001). However, there was no such association between LDH and melanoma stage and risk. Further study indicated that the MIA cut-off > 914.7pg/mL predicted disease progression with 86.4% specificity and 95.5% sensitivity. In the Kaplan-Meier analysis, MIA levels were independent risk factors for long-term mortality of acral malignant melanoma patients.It concluded that the quantification of MIA in the serum should be performed as a general standard of care in patients at risk of developing metastatic melanoma.  相似文献   
90.
Leukotrienes (LTs) are involved in many inflammatory conditions including gastric damage induced by nonsteroidal anti-inflammatory drugs. Although LTs stimulate acid secretion, the effect they exert on pepsinogen secretion is unknown. The aim of this study was to investigate whether LTs stimulate pepsinogen secretion by isolated chief cells and to identify the intracellular messengers that mediate this action. Isolated chief cells were incubated with concentrations of LTB4, LTC4, LTD4, or LTE4 ranging from 0.1 pmol/L to 10 μmol/L, and pepsinogen release, intracellular calcium and inositol(1,4,5)-trisphosphate (IP3) concentrations were measured. Nitric oxide generation was determined by the amount of citrulline generated during incubation. All four LTs caused a concentration-dependent stimulation of pepsinogen secretion with 50% effective concentration of 0.05-0.1 nmol/L and a dose-dependent increase in cytoplasmic free calcium and IP3 concentration. The LTB4 and LTD4 antagonists caused selective, concentration-dependent inhibition of LTB4- and LTD4-induced pepsinogen secretion, calcium mobilization, and IP3 generation. All four LTs increased NO generation, and the effect was inhibited by LTB4 and LTD4 antagonists and an NO synthase inhibitor NG-monomethyl-l-arginine and reversed by l-arginine. NG-monomethyl-l-arginine caused a 50%–60% reduction of LT-induced pepsinogen release. Each of the four LTs caused a fivefold increase in 5′-cyclic guanosine monophosphate. LTs are powerful stimulators of pepsinogen secretion in isolated chief cells and act via occupancy of specific cell-surface receptors.  相似文献   
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