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1.
A female infant with nesidioblastosis who showed mild clinical symptoms is reported. In this patient, insulin levels and insulin to glucose ratios (IRI/G) were often normal. Regular milk feedings supplemented with continuous glucose infusion (0.7-2 mg/kg per min) or oral glucose feedings (4.5 mg/kg per min) prevented hypoglycemia. As leucine-sensitivity was diagnosed at 2 months of age, she was started on diazoxide. This was, however, ineffective, and adverse effects appeared. Subtotal pancreatectomy (95%) was therefore attempted at 5 months of age, and persistent normoglycemia as well as normal growth and development followed up to 3 years after the operation. The pancreas showed characteristic signs of nesidioblastosis. The above clinical observation suggests that a patient with nesidioblastosis whose blood glucose level is easily controllable may develop an unexpected episode of hypoglycemia in the presence of a leucine sensitivity. In such a patient, diazoxide or, when it is of no avail, surgical intervention should promptly be instituted to prevent possible neurologic sequelae induced by hypoglycemia.  相似文献   
2.
We studied T cell responses to four glutathione S transferase (GST)-fused mite antigens prepared in our laboratory using peripheral blood lymphocytes from mite-sensitive patients with bronchial asthma. Of the four recombinant antigens, purified GST-Mag3 had the strongest ability to cause patients' lymphocytes to proliferate, and its potency was almost comparable to that of crude mite bodies (Dfb) and faeces (Dff) antigens and a purified major antigen, Der f 2. The responder lymphocytes were mainly T cells, because the proliferative response was depleted by the treatment of lymphocytes with anti-CD3 antibody and complement, but not with anti-CD20 antibody and complement. The responsiveness of lymphocytes to GST-Mag3 correlated with that to Der f 2, but GST-Mag3 displayed slightly higher activity to stimulate lymphocytes than Der f 2. Simultaneously, the levels of Dff- and GST-Mag3-specific IgE antibodies correlated with the responsiveness of lymphocytes to GST-Mag3. These results suggest that Mag3 is a new valuable antigen for the response of T cell proliferation in mite-sensitive patients.  相似文献   
3.
BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
4.
Microdialysis has been used to determine the concentration of salicylic acid in skin tissue and plasma periodically for 4 h to evaluate the effect of ointment bases on topical and transdermal delivery of salicylic acid. The ointment bases examined were solbase (water-soluble), poloid and white petrolatum (oleaginous), hydrophilic poloid (water in oil (w/o) type emulsion lacking water) and absorptive ointment (w/o-type emulsion containing water). The ointments (0.1 g) containing 25 μmol salicylic acid were applied for 2 h to the surface of rat skin (1 cm2) with (intact) or without the stratum corneum. For intact skin, the extent of topical delivery from different ointments, evaluated by the area under the concentration-time curve (AUC) of salicylic acid in the skin tissue (AUCskin), increased in the order solbase. white petrolatum, poloid, hydrophilic poloid. absorptive ointment. The ratio of AUCskin (topical delivery) to the AUC of salicylic acid in plasma (AUCplasma, transdermal delivery) varied remarkably among the different bases, the greatest ratio being observed for absorptive ointment. When the ointments were applied to skin surface without stratum corneum, AUCskin for solbase was much higher (about 45 times that for intact skin), whereas only a small (two-fold) increase was observed for poloid and hydrophilic poloid and the increase was negligible for white petrolatum and absorptive ointment. For skin without the stratum corneum, the ratio AUCskin/AUCplasma for the different ointments was comparable, although the magnitudes of AUCskin and AUCplasma still varied substantially. The variance of AUC values arises as a result of the different rates of release of salicylic acid from the bases. These results indicate that: the topical and transdermal delivery of salicylic acid in intact skin varies substantially among different ointment bases, and the greatest topical delivery is observed for absorptive ointment; use of absorptive ointment increases the retention of salicylic acid in the stratum corneum; and the stratum corneum functions strongly as a penetration barrier for solbase, moderately for poloid and hydrophilic poloid, and less for absorptive ointment and white petrolatum.  相似文献   
5.
Peripheral lymphocytes from eight patients with congenital immunodeficiency diseases were infected with Epstein-Barr virus (EBV) in an attempt to establish B lymphoblastoid cell lines (LCL). These patients included three boys with congenital agammaglobulinaemia, two girls with hypogammaglobulinaemia, one boy with common variable immunodeficiency, one boy with severe combined immunodeficiency with adenosine deaminase deficiency, and one boy with DiGeorge syndrome. Five of the patients bore no surface immunoglobulins (slg) on their peripheral lymphocytes. LCL were established from seven of the eight patients. All the LCL established formed rosettes with EAC3 and had the ability to produce cytoplasmic immunoglobulins (clg) of various classes. Culture supernatants concentrated up to 100-fold developed precipitin bands by Ouchterlony's method with antisera to human Ig in all the established LCL. These results suggested that both slg-, clg- and C3+ cells and slg+, clg- and C3+ cells might be the target cells for EBV and that slg-, clg- and C3+ cells might be the precursor cells of B lymphocytes.  相似文献   
6.
Neuropeptide Y (NPY) has at least three receptors (Y1, Y2 and Y3) through which it influences different mechanisms in many cell types. Previous data suggest that the Y2 receptor may be divided into prejunctional and postjunctional subgroups. We have examined the intracellular signalling pathways of the postjunctional Y2 receptor in rat renal proximal tubules. The results indicate that NPY regulates Na+,K+-ATPase through several signalling pathways: (1) In proximal tubule (PT) cells NPY increased intracellular calcium. The response was blocked by removing extracellular calcium and was also blocked by using nifedipine. This suggests that calcium was increased by influx from the extracellular space through L -type calcium channels. (2) NPY increased Na+,K+-ATPase activity in PT segments and this effect was also blocked by nifedipine. CaMKII-Ala286[281–302] a blocker of Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibited the NPY-stimulated Na+,K+-ATPase activity. This implies that increased intracellular calcium activates CaMKII which subsequently increases Na+,K+-ATPase activity. CaMKII thus appear to act similar to what has been proposed for protein phosphatase 2B. (3) Calphostin C, an inhibitor of protein kinase C (PKC), did not inhibit NPY-stimulated Na+,K+-ATPase activity. PKC is, therefore, unlikely to be involved. (4) Y2 receptors are negatively coupled to the cAMP pathway. NPY attenuated forskolin-stimulated cAMP production in renal tubules and exogenous cAMP counteracted the NPY-stimulated Na+,K+-ATPase activity. This illustrated the importance of NPY for the regulation of renal sodium handling. We also propose that the renal tubule cell is a good model for studying the function and mechanisms of postjunctional Y2 receptors.  相似文献   
7.
The effect of temperature on the potencies of neuromuscularblocking agents remains unclear. This study was undertaken toexamine the effects of different neuromuscular blocking agentsat 37 and 27 °C at a constant carbon dioxide content ( statprinciple). The effect of neostigmine 1 µmol litre–1induced antagonism of these agents was also investigated. Phrenicnerve-hemidiaphragm preparations of rats were mounted in modifiedKrebs solution, maintained at 37 CC and aerated with a 5% carbondioxide-95% oxygen gas mixture, and at 27 °C with 4% carbondioxide to maintain the carbon dioxide content of the solutionconstant. Phrenic nerves were stimulated with 0.1 -Hz supra-maximalimpulses of 0.2-ms duration and the elicited tension of thediaphragm recorded. The potencies of the steroidal neuromuscularblocking agents (rocuronium, vecuronium, pancuronium and pipecuronium)increased significantly at 27 °C (P<0.05), while thepotencies of the benzyliso-quinolinium agents (tubocurarineand dimethyl-tubocurarine) did not change. Neostigmine-inducedantagonism of the steroidal agents did not differ significantlybetween each other but differed significantly from the benzylisoquinoliniumagents (P<0.05) at both temperatures. The ratios of IC50(inhibitory concentration, 50%) with and without neostigmineat hypothermia were slightly higher for the steroidal agents,indicating slight enhancement of antagonism by neostigmine at27 °C. In contrast, the ratios were significantly greaterat 27 °C (P<0.05) for isoquinolinium agents, implyingsignificant enhancement of antagonism. Our results indicatethat at 27 °C the potency of all steroidal agents increasedand neostigmine-induced antagonism was slightly enhanced. Withthe isoquinolinium agents, hypothermia caused no change in potencyalthough neostigmine-induced antagonism was enhanced significantly.These findings suggest that the relative effects of steroidaland isoquinolinium agents on the neuromuscular junction aredifferent or that they have a different mechanism of actionon the neuromuscular junction.  相似文献   
8.
Various types of fibromatosis have been reported in infancy and early childhood. We describe an infant with diffuse fibromatosis on the scalp. A one year and five months-old girl showed a diffuse and hard mass 3 × 5 cm in diameter and no tenderness on the scalp. Two months later, the size of the mass had increased and several other tumors appeared on the lateral head. The magnetic resonance imaging (MRI) disclosed that a large and diffuse tumor had spread from the frontal to occipital head; a ‘helmet-like’ configuration of the tumor was exhibited on sagittal MR images. The tumor showed high signal intensity on T2-weighted images and was enhanced with Gd-DTPA. Histological examination showed a fibroblastic proliferation with intervening thick collagen bundles. The patient was diagnosed as having diffuse fibromatosis. The tumor at the resection site immediately recurred, whereas the tumor in the frontal head showed marked regression. Three months after the resection, new tumors appeared in the occipital head. The size and number of these tumors have remained unchanged for more than 18 months. The sites and appearance of the tumors were identical to that of juvenile hyaline fibromatosis (JHF) in this patient. However, JHF usually includes fibroblasts associated with large amounts of hyalinized collagen-like material, which were not present in our patient. The different histology of JHF comparing our case and other reported cases may depend on the different phase of the disease progression at resection. Long-term observation is necessary for the appropriate diagnosis and evaluation of prognosis in this patient.  相似文献   
9.
Two distinct hereditary defects, vitamin D-dependent rickets type I (VDDR I) and type II (VDDR II), have been recognized in vitamin D metabolism. VDDR I is suggested to be a deficiency of the renal 25-hydroxyvitamin D (25(OH)D)-1α-hydroxylase. Muscle weakness and rickets are the prominent clinical findings. A normal physiologic dose of 1α-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 is sufficient to maintain remission of rickets in this disorder. VDDR II consists of a spectrum of intracellular vitamin D receptor (VDR) defects and is characterized by the early onset of severe rickets and associated alopecia. This can be attributed to mutations in the VDR gene. Massive doses of vitamin D analogs and calcium supplementation is usually required for the treatment; however, the response to therapy is sometimes variable.  相似文献   
10.
Aim: To assess the physical and mental burdens associated with expressing empathy with another person's stress. Methods: Nine female subjects listened to their partner's negative emotions aroused by a stress task (Stroop color‐word test) under two conditions. In the first, the subject reacted empathetically to their partner (“with empathy”); in the second, the subject offered no response (control). Electroencephalograms and skin temperature of the second finger were recorded during the test. Subjective stress was estimated using a visual analog scale, whereas the level of cognition was expressed on a five‐point ranking. Responses during and after expressions of empathy were examined by comparisons with control or by correlation. Results: Sympathetic nerve tone increased under both conditions (i.e. the skin temperature of the second finger fell). Subjective stress was not recognized by the subject while listening “with empathy”, although it did increase significantly after the subject has listened “with empathy”. Subjective stress was not felt under the control conditions. Right temporal activity while listening showed a significantly positive correlation with the level of cognition of feeling the same emotion as the stressed partner, whereas bilateral frontal activity after listening was significantly negative correlated with the level of cognition of understanding the emotions of the stressed partner. Conclusion: Expressing empathy with another person's negative emotion led to increased physiological activity and subjective stress. Physiological responses to empathy depended on cognition of the different subjective factors. Cognition of sharing negative emotions activated the right temporal region of the brain, whereas cognition of understanding negative emotions inhibited bilateral frontal activities.  相似文献   
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