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21.
对13例有囊性纤维化营养不良的患者(3例男性,平均年龄18.1岁)进行食品添加物与饮食指导的对照研究。在3个月后对其进行能量摄入状况及营养状况评估。结果发现:在能量摄入或理想体重百分比方面两组都无明显改变。  相似文献   
22.
The retinotoxic, sulfhydryl-binding drug, iodoacetic acid (IAA), affects embryonic chick retinal pigmented epithelial (RPE) cells grown in primary cultures in a reversible, dose-dependent manner. A dose of 5 X 10(-4) M which produces drastic cell shape changes in about 90 min was chosen to study the effects of IAA on the organization of cytoskeleton and adhesiveness in RPE cells. After treatment of cells with IAA microtubules depolymerize and F-actin becomes redistributed from numerous stress fibers to knob-like aggregates. Vinculin is released from focal contacts and adhesions into the cytosol and, at the same time, adhesiveness of the RPE cells to substratum decreases. Since RPE in vitro is susceptible to the action of IAA, it seems possible that also in vivo some of the retinotoxic effects of IAA might be attributed to its damaging influence on the RPE. Thus, the retinotoxic effects of IAA in vivo cannot be solely attributed to the selective degeneration of photoreceptors by this agent.  相似文献   
23.
Summary: Purpose : We studied cerebral perfusion patterns in the various subtypes of TLE, as determined by pathology and good outcome after temporal lobectomy (as confirmation of temporal origin).
Methods : We studied clinical features and ictal technetium 99m hexamethyl-propyleneamineoxime (99mTc-HM-PAO) single-photon emission-computed tomography (SPECT) in four subgroups of patients with intractable temporal lobe epilepsy (TLE) treated with surgery: hippocampal sclerosis (group 1, n = 10), foreign-tissue lesion in mesial temporal lobe (group 2, n = 8), foreign-tissue lesion in lateral temporal lobe (group 3, n = 7), and normal temporal lobe tissue with good surgical outcome (group 4, n = 5).
Results : No major clinical differences in auras, complex partial seizures or postictal states were identified among the groups. Ictal SPECT showed distinct patterns of cerebral perfusion in these subtypes of TLE. In groups 1 and 2, hyperperfusion was seen in the ipsilateral mesial and lateral temporal regions. In group 3, hyperperfusion was seen bilaterally in the temporal lobes with predominant changes in the region of the lesion. Hyperperfusion was restricted to the ipsilateral anteromesial temporal region in group 4. Ipsilateral temporal hyperperfusion in mesial onset seizures can be explained by known anatomic projections between mesial structures and ipsilateral temporal neocortex. Bilateral temporal hyperperfusion in lateral onset seizures can be explained by the presence of anterior commissural connections between lateral temporal neocortex and the contralateral amygdala.
Conclusions : We conclude that the perfusion patterns seen on ictal SPECT are helpful for subclassification of temporal lobe seizures, whereas clinical features are relatively unhelpful. These perfusion patterns provide an insight into preferential pathways of seizure propagation in the subtypes of TLE.  相似文献   
24.
Following a clinical experience of 100 cardiac operation in infants durind deep hypothermia, as low as 15C, the authors have designed a new bath for the procedure which incorporates several improvements over those used previously. The device described allows continuous cooling or rewarming of the patient at any stage of the operation by addition of more cold or hot water as required. It is possible to operate with the patient prone or on the side at any level of hypothermia, and while using heart lung bypass. The construction facilitates the even distribution of the circulating water, and a thermostatic control allows the temperature to be fixed at any level required.  相似文献   
25.
Postmortem autoradiography was used to explor the mechanisms underlying L-dopa resistance in 2 patients with multiple-system atrophy. Indices of striatal presynaptic dopamine terminal loss and dopamine (D1 and D2) receptors were provided by 3H-SCH 23390, and 123I-sulpiride binding. Neuronal loss, gliosis, and loss of postsynaptic D2 receptors preferentially involved the middle and posterior of the putamen, that region of the striatum most intimately involved in motor function. Loss of D1 receptors in the same area occurred in only 1 patient. These findings suggest that in multiple-system atrophy, resistance to L-dopa is due to a loss of putamental D2 receptors. The differential effects on D1 and D2 receptors in 1 patient implies that different subpopulations of striatal neurons were selectively involved.  相似文献   
26.
BOOK REVIEW     
Discharge planning for health care facilities . Faith J. Crittenden Bowie, Maryland: Robert J. Brady Company, 1983; 172 pages, plus appendices, bibliography, and index; total 211, $19.95.  相似文献   
27.
Action potentials and release of neurohypophysial hormones in vitro   总被引:8,自引:4,他引:4       下载免费PDF全文
1. Isolated rat neurohypophyses were studied in vitro and the hormones released on electrical stimulation of the pituitary stalk or on exposure to excess potassium were estimated by a milk-ejection assay.2. The stalk was stimulated with trains of 500 stimuli, or multiples thereof, applied at different frequencies. Below frequencies of ca. 35 c/s, hormone release was found to depend on the total number of stimuli applied as well as on the frequency of stimulation. Above ca. 35 c/s, identical numbers of stimuli were progressively less effective as the frequency of stimulation was increased, and the dependence of the hormone output on the total number of stimuli was less apparent.3. The amplitude of the compound action potential recorded from the neurohypophysis following electrical stimulation of the stalk was found to decrease as a function of the frequency of stimulation. Stimulation at 50 c/s reduced its amplitude about sevenfold within 30 sec.4. The addition of tetrodotoxin (TTX) to the incubation media abolished the compound action potential recorded from the neural lobe as well as the release of hormones evoked by electrical stimulation. Resting release, however, was unaffected by TTX.5. In TTX-treated neural lobes, excess potassium was still effective in eliciting graded secretory responses. This indicates the independence of the release process from the action potential generating mechanism and suggests that TTX-paralysed preparations represent a useful model for the study of hormone release in the absence of conducted action potentials.6. The release of hormones from the neurohypophysis and the release of neurotransmitters at chemical synapses both depend on the entry of calcium into the nerve terminals following their depolarization by invading action potentials. In both systems, experimental separation of the release mechanism can be achieved by the use of TTX. These and other parallels suggest that the release process is similar.  相似文献   
28.
29.
Enamel formation has been observed in six of seventeen solid, cystic, acanthomatous or dentigerous (mural) ameloblastomas. Droplets of young, transitional, semi-mineralized or more fully mineralized enamel structures have been observed. Amelogenesis in ameloblastomas unrelated to dentine formation is similar to the findings of atypical amelogenesis in animal experiments. The presence of enamel droplets surrounded by ameloblasts in an ameloblastoma indicates that, as in certain other neoplasms, a high degree of differentiation may be achieved.  相似文献   
30.
The watery diarrhea-hypokalemia-achlorhydria syndrome associated with ectopic secretion of vasoactive intestinal peptide has only been conclusively documented with tumors originating in the pancreas or sympathetic chain. We report here the case of a 50-yr-old woman who developed this syndrome 3 wk after an apparently effective course of radiotherapy for an obstructing, mixed-cell carcinoma of the esophagus. High concentrations of vasoactive intestinal peptide were found in plasma (100-200 pmol/L; normal less than 20 pmol/L) and in the metastatic skin nodules (750 pmol/g) that later developed and that contained one of the two cell types from the original tumor. Stool volumes reached a plateau of 15-20 L/day, and potassium requirements were greater than 1000 mmol/day. Symptoms failed to respond to any of the regimens previously described as effective in this syndrome. After 14 wk of massive fecal fluid and electrolyte losses, symptoms resolved dramatically with the first dose of 5-fluorouracil. Plasma vasoactive intestinal peptide concentration returned to normal, where it remained despite subsequent evidence of renewed tumor spread. This case illustrates the unpredictability of the response of this syndrome to medical treatment, and suggests that vasoactive intestinal peptide secretion may occur in a wider range of tumors than has so far been described.  相似文献   
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