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1.
The transition from regular ovarian cyclicity to menopause is associated with a rise in the circulating concentrations of follicle stimulating hormone (FSH), despite the maintenance of serum oestradiol concentrations during the perimenopause. The aim of this study was to compare the pattern of secretion of dimeric inhibins, activin A, gonadotrophins and steroids in regularly cycling women of 40-50 years with normal and raised early follicular phase serum FSH concentrations and young women (25-33 years) during the menstrual cycle. Blood samples were taken prospectively almost daily throughout the menstrual cycle. Women recruited were classified into three groups: (i) older women with normal FSH [(ON-FSH), day 3 FSH <8 mIU/ml, n = 10]; (ii) older women with raised FSH [(R-FSH), day 3 FSH >8 mIU/ml, n = 6] and (iii) young normal FSH (YN-FSH) women, age 25-32 years (n = 6). Cyclic patterns of serum inhibins and activin A were similar in the ON-FSH and YN-FSH groups. The R-FSH group had significantly lower concentrations of inhibin A prior to the luteinizing hormone (LH) surge and in the mid-luteal phase and lower concentrations of inhibin B in the early follicular phase compared with the ON-FSH group. Serum concentrations of activin A, progesterone and oestradiol were similar in all three groups. It is concluded from this study that the rise in early follicular phase serum FSH in older women is associated with a decrease in circulating concentrations of inhibin B in the early follicular phase. However, lower circulating concentrations of inhibin A in the luteal phase of the R-FSH group may also contribute to the rise in early follicular phase FSH concentrations during the menstrual cycle, although further studies with larger numbers are required to confirm this observation.  相似文献   
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In March 2020, a national elimination strategy for coronavirus disease was introduced in New Zealand. Since then, hospitalizations for lower respiratory tract infection among infants <2 years of age and cases of respiratory syncytial or influenza virus infection have dramatically decreased. These findings indicate additional benefits of coronavirus disease control strategies.  相似文献   
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BACKGROUND: The metabolic syndrome is a disorder that includes dyslipidemia, insulin resistance, and hypertension and is associated with an increased risk of diabetes and cardiovascular disease. We determined whether patterns of regional fat deposition are associated with metabolic syndrome in older adults. METHODS: A cross-sectional study was performed that included a random, population-based, volunteer sample of Medicare-eligible adults within the general communities of Pittsburgh, Pa, and Memphis, Tenn. The subjects consisted of 3035 men and women aged 70 to 79 years, of whom 41.7% were black. Metabolic syndrome was defined by Adult Treatment Panel III criteria, including serum triglyceride level, high-density lipoprotein cholesterol level, glucose level, blood pressure, and waist circumference. Visceral, subcutaneous abdominal, intermuscular, and subcutaneous thigh adipose tissue was measured by computed tomography. RESULTS: Visceral adipose tissue was associated with the metabolic syndrome in men who were of normal weight (odds ratio, 95% confidence interval: 2.1, 1.6-2.9), overweight (1.8, 1.5-2.1), and obese (1.2, 1.0-1.5), and in women who were of normal weight (3.3, 2.4-4.6), overweight (2.4, 2.0-3.0), and obese (1.7, 1.4-2.1), adjusting for race. Subcutaneous abdominal adipose tissue was associated with the metabolic syndrome only in normal-weight men (1.3, 1.1-1.7). Intermuscular adipose tissue was associated with the metabolic syndrome in normal-weight (2.3, 1.6-3.5) and overweight (1.2, 1.1-1.4) men. In contrast, subcutaneous thigh adipose tissue was inversely associated with the metabolic syndrome in obese men (0.9, 0.8-1.0) and women (0.9, 0.9-1.0). CONCLUSION: In addition to general obesity, the distribution of body fat is independently associated with the metabolic syndrome in older men and women, particularly among those of normal body weight.  相似文献   
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BackgroundWe compared physical functioning, mental health, and quality of life (QoL) of patients with different subtypes of congenital heart disease (CHD) in a large international sample and investigated the role of functional class in explaining the variance in outcomes across heart defects.MethodsIn the cross-sectional Assessment of Patterns of Patient-Reported Outcome in Adults with Congenital Heart Disease-International Study (APPROACH-IS), we enrolled 4028 adult patients with CHD from 15 countries. Diagnostic groups with at least 50 patients were included in these analyses, yielding a sample of 3538 patients (median age: 32 years; 52% women). Physical functioning, mental health, and QoL were measured with the SF-12 health status survey, Hospital Anxiety and Depression Scale (HADS), linear analog scale (LAS) and Satisfaction with Life Scale, respectively. Functional class was assessed using the patient-reported New York Heart Association (NYHA) class. Multivariable general linear mixed models were applied to assess the relationship between the type of CHD and patient-reported outcomes, adjusted for patient characteristics, and with country as random effect.ResultsPatients with coarctation of the aorta and those with isolated aortic valve disease reported the best physical functioning, mental health, and QoL. Patients with cyanotic heart disease or Eisenmenger syndrome had worst outcomes. The differences were statistically significant, above and beyond other patient characteristics. However, the explained variances were small (0.6% to 4.1%) and decreased further when functional status was added to the models (0.4% to 0.9%).ConclusionsSome types of CHD predict worse patient-reported outcomes. However, it appears that it is the functional status associated with the heart defect rather than the heart defect itself that shapes the outcomes.  相似文献   
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OBJECTIVE: The feto-placental unit is the major source of circulating concentrations of inhibin A and activin A in human pregnancy. The aim of this study was to measure the amniotic fluid concentrations of inhibin A, inhibin B, activin A and follistatin in pregnancies bearing male and female fetuses. DESIGN AND METHOD: Amniotic fluid samples collected by amniocentesis were stored at -20 degrees C. Dimeric inhibins, 'total' activin A and 'total' follistatin were measured using specific two-site enzyme immunoassays. Samples were assayed blindly and the information on fetal sex was obtained from the cytogenetics laboratory. RESULTS: Data show that amniotic fluid concentrations of inhibin A, inhibin B and activin A gradually increase with gestation whilst concentrations of follistatin are similar between weeks 15 and 20 of pregnancy. Mean amniotic fluid levels of inhibin A and inhibin B at 16 and 17 weeks gestation and mean activin A levels at 15 and 16 weeks gestation are considerably lower in pregnancies with male (n=24) compared with female (n=28) fetuses. Levels of follistatin are not different in the male and female fetal pregnancies at any studied gestation. CONCLUSIONS: The results indicate that amniotic fluid contains high concentrations of inhibins (A and B), activin A and follistatin in early pregnancy suggesting that these hormones are produced by the fetal membranes and may be involved in the development of the fetus.  相似文献   
8.
Corticosteroids (oral or inhaled) are commonly used to treat pulmonary sarcoidosis; however, there is no consensus about when to start treatment, what dose of steroids to give and for how long. Immunosuppressive and cytotoxic agents (used in immunosuppressive doses) are used in addition to oral corticosteroids to treat multisystem and chronic sarcoidosis, or as steroid-sparing agents. We summarize the findings from two Cochrane systematic reviews that have examined the efficacy of corticosteroids and immunosuppressive and cytotoxic drugs in the treatment of pulmonary sarcoidosis. Studies of corticosteroids differed in outcome measures, dose of drug given and length of treatment. For many outcome measures, data could not be pooled for meta-analysis. Oral corticosteroids improved chest X-ray appearance over 3-24 months, with improvement in global score in one study. Little evidence was found of improvement in lung function or of any long-term disease-modifying effect. Follow-up data could not be analysed. Inhaled corticosteroids improved symptoms in one small study but not lung function or chest X-ray. Side-effects of steroids were not well reported. In the immunosuppressive and cytotoxics review, no data could be combined for meta-analysis. Data on lung function, chest X-ray and dyspnoea were largely inconclusive. Methotrexate had a steroid-sparing effect in one small study. Significant adverse events were associated with cyclosporine A, chloroquine and pentoxifylline. Evidence from randomized-controlled trials (RCTs) supporting the use of immunosuppressive and cytotoxic agents is limited.  相似文献   
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Little information is available on the effects of activin and inhibin on the synthesis and secretion of pituitary gonadotrophins in species other than the rat. In this in-vitro study, ovine pituitary cell cultures derived from immature sheep were used to investigate the effects of recombinant human activin-A and native Mr 32,000 bovine inhibin on basal and gonadotrophin-releasing hormone (GnRH)-induced release of FSH and LH. Residual cellular contents of FSH and LH were also determined, allowing total content/well to be calculated. Activin-A promoted a dose-dependent increase in basal (+72%; P less than 0.001) and GnRH-induced (+25%; P less than 0.001) release of FSH as well as in the residual cell content (+114%; P less than 0.001) and total FSH content/well (+67%; P less than 0.001). Conversely, inhibin significantly (P less than 0.001) suppressed each aspect of FSH production examined, confirming that in sheep, as in rats, activin and inhibin exert opposing effects on pituitary FSH production. In contrast to the rat, however, in which activin is reported to have no effect on LH secretion, exposure of sheep pituitary cells to activin-A promoted a dose-dependent suppression (-42%; P less than 0.001) of GnRH-induced LH release. This was associated with a corresponding increase (P less than 0.001) in residual cellular content of LH. Consistent with a previous report from this laboratory, inhibin had the opposite effect and significantly enhanced (+47%; P less than 0.001) GnRH-induced LH release. This was associated with a corresponding fall (P less than 0.01) in residual cellular content of LH.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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