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101.
Recently, human amniotic fluid (AF) cells have attracted a great deal of attention as an alternative cell source for transplantation and tissue engineering. AF contains a variety of cell types derived from fetal tissues, of which a small percentage is believed to represent stem cell sub-population(s). In contrast to human embryonic stem (ES) cells, AF cells are not subject to extensive legal or ethical considerations; nor are they limited by lineage commitment characteristic of adult stem cells. However, to become therapeutically valuable, better protocols for the isolation of AF stem cell sub-populations need to be developed. This study was designed to examine the molecular components involved in self-renewal, neural commitment and differentiation of AF cells obtained at different gestational ages. Our results showed that, although morphologically heterogeneous, AF cells derived from early gestational periods ubiquitously expressed KERATIN 8 (K8), suggesting that the majority of these cells may have an epithelial origin. In addition, AF cells expressed various components of NOTCH signaling (ligands, receptors and target genes), a pathway involved in stem cell maintenance, determination and differentiation. A sub-population of K8 positive cells (<10%) co-expressed NESTIN, a marker detected in the neuroepithelium, neural stem cells and neural progenitors. Throughout the gestational periods, a much smaller AF cell sub-population (<1%) expressed pluripotency markers, OCT4a, NANOG and SOX2, from which SOX2 positive AF cells could be isolated through single cell cloning. The SOX2 expressing AF clones showed the capacity to give rise to a neuron-like phenotype in culture, expressing neuronal markers such as MAP2, NFL and NSE. Taken together, our findings demonstrated the presence of fetal cells with stem cell characteristics in the amniotic fluid, highlighting the need for further research on their biology and clinical applications.  相似文献   
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An in vivo assessment for the protective effects of silymarin for pyridine toxicity was investigated through cytochrome P450 isoform CYP1A1 and inducible nitric oxide synthase (iNOS) activity prevention. Moreover, the effect of pyridine-induced oxidative stress on metallothionein I-II (MT), a scavenger of oxygen-derived free radicals, was investigated. Forty Syrian hamsters were allocated into 4 groups. Syrian hamsters were dosed with pyridine (400 mg/kg) intraperitoneally with and without silymarin (200 mg/kg daily by gavage) for 4 days. Pyridine induced diffuse degeneration and necrosis of the proximal and distal renal tubular cells; cloudy swelling, necrosis and hepatocellular atypia of the liver; and degenerative changes in the myocardium. The degree of pathological alterations was less severe with simultaneous silymarin application. CYP1A1, iNOS and MT expression levels were elevated in liver, kidney and heart in response to acute pyridine toxicity. Silymarin application abolished or significantly suppressed the induction of CYP1A1, iNOS and MT expressions in liver, kidney and heart of the pyridine-treated Syrian hamsters. Enhanced synthesis of MT by pyridine possibly implies a purposive cellular response to prevent damage caused by oxygen radicals. However, silymarin significantly reduced the oxidative-stress-inducing effect of pyridine as reflected by decreased synthesis of MT. These results suggest that through oxidant generation, pyridine may cause alteration of the metabolic ways, including nitric oxide-mediated CYP1A1 activity.  相似文献   
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Hirsutism is a common clinical problem in women and the treatment depends on the cause of hirsutism. The study was designed to determine the various causes of hirsutism and their prevalences in a Turkish population. 168 women with hirsutism attending to Endocrinology Outpatient Clinic of Erciyes University Hospital were investigated in detail. Medical history, physical examination, and basal levels of free testosterone (fT), androstenedione, follicle-stimulating hormone (FSH), luteinizing hormone (LH), dehydroepiandrosterone-sulphate (DHEAS), 17 hydroxyprogesterone (17-OHP), 11-deoxycortisol (11-S), thyroid hormones, thyroid stimulating hormone (TSH), and prolactin were determined. ACTH stimulation test was performed for the diagnosis of non-classic congenital adrenal hyperplasia (NCAH). Pelvic/vaginal and adrenal ultrasonographies were performed for the detection of tumors and polycystic ovarian changes. Polycystic ovary syndrome (PCOS) was diagnosed in 96 (57.1 %) patients, idiopathic hirsutism in 27 (16 %), NCAH in 12 (7.1 %), adrenal carcinoma in 3 (1.8 %), and Cushing's disease in 1 (0.6 %) patient. Among patients with NCAH, 11 (91.7 %) patients had 11-beta hydroxylase (11-beta OH) deficiency, and 1 (8.3 %) had 21-hydroxylase deficiency. The etiology of hyperandrogenemia was not clear in 29 (17.4 %) patients and these patients were named as idiopathic hyperandrogenemia. The clinical presentation of 11-beta OH deficiency is indistinguishable from that of other hyperandrogenic states and ACTH stimulation test is the only way to diagnose this entity. Although PCOS is the most common cause of hirsutism, it is notable that nearly one fifth of hirsute women have no apparent cause of hyperandrogenemia.  相似文献   
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Neuroanatomic abnormalities have been implicated in the pathophysiology of obsessive-compulsive disorder (OCD). To date, no study has measured the orbito-frontal cortex (OFC), anterior cingulate, caudate nucleus, and thalamus concurrently in first-episode patients. Thus, we performed a volumetric MRI study in patients who were treatment-naive and healthy controls focusing on the in vivo neuroanatomy of the whole brain, total gray and white matter volume, thalamus, caudate nucleus, anterior cingulate cortex, and OFC concurrently. The volumes of thalamus, caudate nucleus, anterior cingulate cortex, and OFC were measured in 12 OCD patients who were treatment-naive and 12 healthy control subjects. Anterior cingulate and OFC volumes included both white and gray matters. Volumetric measurements were made with T1-weighted coronal MRI images, with 1.5-mm-thick slices, at 1.5 T. The patients had increased white matter volume than healthy controls. The patient group had significantly smaller left and right OFC volumes and significantly greater left and right thalamus volumes compared with healthy controls. Anterior cingulate exhibited a near-significant difference between the patients and healthy controls on left side. Significant correlations were found between Y-BOCS scores and left OFC, and right OFC, and between Y-BOCS and left thalamus volumes in the patient group. In conclusion, our findings suggest that abnormalities in these areas may play an important role in the pathophysiology of OCD.  相似文献   
108.
The purpose of this study was to compare the quantitative parameters of salivary gland functions in patients with allergic rhinitis and healthy volunteers using [99mTc] pertechnetate salivary gland scintigraphy. Thirty-six patients with allergic rhinitis (14 males and 22 females, mean age 30.6 ± 5.2 years) and thirty-nine healthy controls (18 males and 21 females, mean age 32.2 ± 5.6 years) were evaluated. Dynamic salivary gland scintigraphy was performed after intravenous administration of 185 MBq (5 mCi) of [99mTc] pertechnetate for 25 minutes. Lemon juice was used to stimulate the salivary glands. On the basis of the time-activity curves, the following glandular function parameters were calculated for the parotid and submandibular salivary glands: uptake ratio, maximum accumulation, and ejection fraction. Statistically, all the functional parameters of the parotid and submandibular glands obtained for the allergic rhinitis patients were significantly lower than those of the healthy controls group (p < 0.05). This study demonstrated that there was a significant difference in salivary gland function between patients with allergic rhinitis and healthy controls, which can easily be evaluated by [99mTc] pertechnetate salivary gland scintigraphy.  相似文献   
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Movement and anxiety during echocardiographic study may reduce the reliability and affect the quality of echocardiographic images. Thus, sedation is an essential component when it is performed in infants. This randomized, single-blinded, placebo-controlled study was undertaken to evaluate the acceptability and effectiveness of intranasal midazolam (INM) versus oral midazolam (OM) in infants during transthoracic echocardiography. Eighty patients between the ages of 6 mo and 3 y who presented for elective echocardiographic study were divided into 3 groups: the OM group received 0.4 mg/kg of injectable midazolam mixed with an equal volume of cherry juice, the INM group received 0.2 mg/kg as drops, and the control group was given oral cherry juice or intranasal serum physiologic. A blinded clinician assessed and scored the level of sedation and comfort during the procedure for each child, and a score for ease of administration was recorded by the nurse. The intranasal route was more acceptable to infants than the oral route (P<.001). No significant difference in the effects of sedation was observed between the OM group and the INM group (P=.583), but significant differences were observed between the sedated groups and the control group (P<.001). The procedure was significantly more comfortable in groups given OM and INM than in the control group (P<.001). Although no difference in sedation score was seen between the oral and nasal routes, INM was better accepted by infants than OM. Echocardiography was performed more reliably and comfortably in those given midazolam than in those in the control group.  相似文献   
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