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1.
We reviewed the treatment outcome of 69 patients with Ewing's sarcoma of the femur. The patients received chemotherapy according to the CESS 81 (n 14), CESS 86 (n 43), and CESS 91P (n 12) protocols. The 10-year relapse-free survival rates were 36%, 65%, and 65% (p = 0.01). 68 patients received local treatment. The primary tumor was treated by surgery without radiotherapy in 28 patients; 1 developed a local recurrence and 7 metastases. 10 patients received radiotherapy alone; 4 developed metastases and 4 local recurrences and metastases. 30 cases had a combination of surgery and radiotherapy; 7 developed metastases and 1 a local recurrence and metastasis. The survival of patients after radiotherapy alone was worse than that of patients after surgery with/without radiotherapy (p = 0.005). Pathological fractures (n 16) did not influence the prognosis.  相似文献   
2.
Assisted reproduction (IVF/ICSI) is an established method for the treatment of infertility, though it entails a number of risks and limiting factors for the children and their families that really have to be considered and resolved. They also must be part of informative consultations before applying the selected (methods)/techniques. The following risks are of prime importance: 1. The increasing number of multiple pregnancies. Every multiple pregnancy has to be regarded as a complication of reproductive medicine: the rate of neonatal morbidity and mortality is higher compared to single pregnancies, and the emotional, logistic, and financial factors are significant for the concerned families. To limit these risks, it is preferable to perform only a single embryo transfer even though a lower rate of resulting pregnancies is to be expected. Of course it must be simultaneously provided that methods are developed and applied to transfer an embryo with high implantation potency. Based on existing/present results, the highest priority should not be given to pregnancy rates as high (as possible) but to the lowest possible complication rate for the infant with an acceptable pregnancy rate comparable to that achieved in fertile couples. 2. In assisted reproduction, the risk of fetal abnormalities seems to be elevated, but in some studies, according to the German IVF register, the selected method (ICSI) and other factors such as family abnormalities and environmental factors are relevant. Additional studies are required to clarify this subject and develop possible preventive strategies. 3. The children's psychomotoric development is normal as a rule. The risk of handicaps (retarded development spastic cerebral palsy) increases in accordance with the reduction of gestational period/age and the decrease of birth weight. This in turn is of particular significance in multiple pregnancies.  相似文献   
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In the luminal membrane of rat cortical collecting duct (CCD) a big Ca2+-dependent and a small Ca2+-independent K+ channel have been described. Whereas the latter most likely is responsible for the K+ secretion in this nephron segment, the function of the large-conductance K+ channel is unknown. The regulation of this channel and its possible physiological role were examined with the conventional cell-free and the cell-attached nystatin patch-clamp techniques. Patch-clamp recordings were obtained from the luminal membrane of isolated perfused CCD segments and from freshly isolated CCD cells. Intracellular calcium was measured using the calcium-sensitive dye fura-2. The large-conductance K+ channel was strongly voltage- and calcium-dependent. At 3 mol/l cytosolic Ca2+ activity it was half-maximally activated. At 1 mmol/l it was neither regulated by cytosolic pH nor by ATP. At 1 mol/l Ca2+ activity the open probability (P o) of this channel was pH-dependent. At pH 7.0 P o was decreased to 4±2% (n=9) and at pH 8.5 it was increased to 425±52% (n=9) of the control. At this low Ca2+ activity the P o of the channel was reduced by 1 mmol/l ATP to 8±4% (n=6). Cell swelling activated the large-conductance K+ channel (n=14) and hyperpolarized the membrane potential of the cells by 9±1 mV (n=23). Intracellular Ca2+ activity increased after hypotonic stress. This increase depended on the extracellular Ca2+ activity. A possible physiological function of the large-conductance K+ channel in rat CCD cells may be the reduction of the intracellular K+ concentration after cell swelling. Once this channel is activated by increases in the cytosolic Ca2+ activity it can be regulated by changes in cellular pH and ATP.Supported by DFG Schl 277/2-3  相似文献   
5.
In two retrospective clinical studies was investigated the influence of the modern non-steroidal antirheumatic drugs indometacin and diclofenac (Rewodina) on the thyroid gland and corresponding peripheral hormone parameters. Under longterm treatment with indometacin a moderate strumigenic effect could be observed, which could not clearly be proved under the diclofenac therapy. In all patients with rheumatoid arthritis, independent of the kind of pharmacotherapy, decreased T3-hormone levels were found in normal serum T4-values. The findings are discussed as "low-T3-syndrome" in rheumatoid arthritis, induced by the disease lasting for many years possibly in combination with the long-term therapy with antirheumatic drugs. In a second series of investigations in 75 out of 3,104 patients (2.4%) with a bland struma distinct references to a medicamentous evocation of the enlargement of the thyroid gland were found. Anticonvulsive drugs and the antidepressive drug lithium stood in the first place as inductors of such medicamentous struma. Of the non-steroidal antirheumatic drugs only some cases could be ascribed to phenylbutazone, whereas the more modern preparations indometacin and diclofenac in none of our patients could with certainty be made responsible for a development of struma.  相似文献   
6.
Ion channel current amplitudes () and open probabilities (P o) have been analysed so far by defining a 50% threshold to distinguish between open and closed states of the channels. With this standard method (SM) it is very difficult or even impossible to analyse channels of different size in one membrane patch correctly. A stochastical model, named the hidden Markov model (HMM), separates between observation noise and the stochastic process of opening and closing of ion channels. The HMM allows the independent analysis of , P o, and mean dwell times () of different channels in one membrane patch, without defining threshold levels. Using this method errors in the analysis are not summarized like in the SM because all different analysing procedures (e. g. filtering, setting of threshold, fitting processes) are done in one step. Two different K+ channels in excised basolateral membranes of the cortical collecting duct of rat (CCD) were analysed by the SM and the HMM. The value of the intermediate-conductance K+ channel (i-K+) was 3.9±0.1 pA (SM) and 3.8±0.2 pA (HMM) for 11 observations. The P o value of this channel was 10.2±4.2% (SM) and 10.1±4.0% (HMM). The mean values were 5.4±0.6 ms for the open state and 9.6±2.2 ms and 145±21 ms for the closed states (SM) and 7.8±1.1 ms, 7.7±0.9 ms and 148±24 ms (HMM), respectively. For seven small-conductance K+ (s-K+) channels, which were found in the same membrane patches as the i-K+, an accurate analysis of P o and was not possible with the SM. The value was 1.0±0.1 (SM), 0.9±0.1 (HMM) pA. P o was 16.6±4.6%, the open value was 11.1±2.8 ms, and the closed value was 34.9±8.5 ms. The HMM allows the analysis of single-channel currents, P o, and mean values when different or more than one ion channel(s) are colocalized in one membrane patch. Where analysis with the SM was possible results did not significantly differ from those obtained with the HMM. Thus for this kind of analysis the method of setting a 50% threshold appears justified.  相似文献   
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目的 分析昆明地区农村超重和肥胖患病现状及村庄与个体间的影响因素.方法 选择石林县作为农村的代表,采用PPS抽样方法对6006名45岁及以上村民通过问卷调查和体格检查获取所需资料;并应用多水平logistic模型分析影响超重和肥胖患病的村庄与个体因素.结果 该地区村民超重率为12.10%,其中男性13.60%,女性10.71%;村民肥胖率为2.15%,其中男性2.82%,女性1.52%;男性的超重率和肥胖率均高于女性.个体和村级因素均与肥胖有关,而超重仅与个体因素有关.在影响超重的因素中,随着年龄的增长患超重的可能性变小(OR=0.95,955% CI:0.83~0.97),男性比女性更容易患超重(OR=0.89,95% CI:0.78~0.98).在影响肥胖的因素中,随着年龄增长患肥胖的可能性变小(OR=0.93,95% CI:0.82~0.96),男性比女性更容易患肥胖(OR=0.87,95% CI:0.78~0.97),收入水平越低者和村庄整体收入水平越低者患肥胖的可能性越大(OR值分别为0.81和0.92;95% CI分别为0.73~0.95和0.85~0.98).结论 对肥胖的干预措施应同时考虑个体和村级水平,肥胖的预防和干预工作应放在村庄整体收入水平较低的村民.  相似文献   
9.
The purpose of this paper is to describe the current modalities of pelvic floor imaging: pelvic floor and endoanal ultrasonography, cystourethrography, evacuation proctography, dynamic colpocystoproctography, magnetic resonance imaging and endoanal magnetic resonance imaging.As there are no set standards for prescribing imaging tests in pelvic floor disorders, we drew up a table of tests to be performed according to the anatomical abnormality observed on physical examination or functional sign reported by the patient.  相似文献   
10.
Objectives

Increasingly, aging societies pose a challenge, particularly in the most developed countries. This trend leads to an increasing group of old and very old patients presenting unique requirements and challenges. One of these challenges consists in reassessment and adaption of established treatment strategies for the elderly patients. There is an ongoing discussion taking place among cranio-maxillo-facial surgeons about the appropriate extent of reconstructive flap surgery for old patients.

Materials and methods

This monocentric retrospective cohort study investigated 281 reconstructions with microvascular flaps by comparing the risk for a negative outcome, which was defined as revision, flap loss, and patient death, between three subgroups of elderly patients and younger patients. The three subgroups of elderly patients were defined as—1: young old (65–74 years), 2: old (75–84 years), and 3: oldest old (≥ 85 years). The group of the younger patients was defined by age between 50 and 64 years. Data were obtained within a defined period of 42 months.

Results

Significant correlations with a negative outcome were found for the variables stay on IMC/ICU, multiple flaps, and radiotherapy prior surgery. Our data showed no significant correlation between age and a higher risk for a negative outcome.

Conclusion

Defect reconstruction with microvascular flaps in old patients is not related with a higher risk for a negative outcome.

Clinical relevance

Independently of age, treatment with microvascular flaps is an option for all operable patients, with an indication for oncologic surgery. For optimal therapy planning, individual patient resources and preferences should be considered instead of chronologic age.

  相似文献   
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