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The degree of concordance of growth rates of primary tumors with corresponding recurrences was investigated by using data from 184 patients with breast cancer with measurable recurrences. For conduction of this examination, the detection processes of both the primary tumor and the recurrence were explored. The probability of detection of a recurrence per unit time was found to be nearly proportional to the tumor's diameter. Approximately 60,000 cells initiated the recurrence, and the distribution of doubling times of the recurrences was exponential, with a mean of 2.1 months. The probability of detection of the primary tumor per unit time was approximately proportional to its volume. The distribution of doubling times of primary tumors was nearly exponential; from other evidence, we inferred that the mean doubling time was also close to 2.1 months. Several techniques to measure growth rate agreement between the primary and recurrent tumors within individuals were developed, and all of them yielded the result that the growth rates are nearly unrelated.  相似文献   
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Purpose

The American Urological Association convened the Clinical Guidelines Panel on Erectile Dysfunction to analyze the literature regarding available methods for treating organic erectile dysfunction and to make practice recommendations based on the treatment outcomes data.

Materials and Methods

The panel searched the MEDLINE data base for all articles from 1979 through 1994 on treatment of organic erectile dysfunction and meta-analyzed outcomes data for oral drug therapy (yohimbine), vacuum constriction devices, vasoactive drug injection therapy, penile prosthesis implantation and venous and arterial surgery.

Results

Estimated probabilities of desirable outcomes are relatively high for vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis therapy. However, patients must be aware of potential complications. The outcomes data for yohimbine clearly indicate a therapy with marginal efficacy. For venous and arterial surgery, based on reported outcomes, chances of success do not appear high enough to justify routine use of such surgery.

Conclusions

For the standard patient, defined as a man with acquired organic erectile dysfunction and no evidence of hypogonadism or hyperprolactinemia, the panel recommends 3 treatment alternatives: vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis implantation. Based on the data to date, yohimbine does not appear to be effective for organic erectile dysfunction and, thus, it should not be recommended as treatment for the standard patient. Venous surgery and arterial surgery in men with arteriolosclerotic disease are considered investigational and should be performed only in a research setting with long-term followup available.  相似文献   
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In a sequential clinical sample of 64 subjects exclusively diagnosed as either biogenically or functionally impotent, Minnesota Multiphasic Personality Inventory (MMPI) and California Psychological Inventory (CPI) standard scales and the Beutler, et al., MMPI signs were all found to be ineffective in realiably classifying patients into the correct diagnostic groupings. Specific item analysis of the MMPI and CPI did identify a significant number of significantly differentiating individual items. Most of these items were shown to be reliably characterizable as indicating either performance anxiety or somatic complaint. Using these classifications of the items, the performance anxiety items were shown, consistent with theory, to be clearly associated with the functional impotence group. The somatic complaint items were shown to be clearly associated with the biogenic impotence group, presumably reflecting the symptoms of physiopathology, such as diabetes, underlying the biogenic condition.  相似文献   
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Renal cell carcinoma with inferior vena cava tumor thrombi   总被引:5,自引:0,他引:5  
Renal cell carcinoma is a unique neoplasm because of its common propensity to propagate into the renal vein and inferior vena cava (IVC) as tumor thrombus. Historically, the surgical difficulties encountered in removal of these cancers limited the ability of a single institution to obtain experience with large numbers of instances. Between January 1956 and July 1987, 68 patients with renal cell carcinoma extending into the IVC or right atrium underwent radical nephrectomy with vena cava thrombus extraction at the Cleveland Clinic. Twenty-five patients had partial resection of the IVC with reconstruction. Fifteen patients had partial resection and reconstruction of the IVC; however, because of narrowing of the infrarenal IVC, persisting bland thrombus in the proximal IVC or iliac veins or concern regarding postoperative pulmonary emboli, the infrarenal IVC was either ligated or clipped. Seven patients underwent cavectomy with division of the IVC. A right atriotomy was performed upon 14 patients and cardiopulmonary bypass was used in 20 patients, with 17 also having deep hypothermic circulatory arrest. The tumor thrombus was removed intact in 64 per cent of the patients and in multiple small fragments ("piecemeal") in 36 per cent of the patients. The mortality rate was 7 per cent. Survival was examined relative to extent of vena caval thrombus. Patients with extension into the atrium had a significantly worse prognosis than those with other levels of vena caval involvement. Other factors, such as lymph node status, perinephric fat involvement, resection of IVC and intact or "piecemeal" extraction, did not influence the survival rate. Patients with pre-existing metastases preoperatively had an extremely poor survival rate. The techniques now available for surgical resection of all levels of tumor thrombus of the IVC make resection feasible in most patients. In our opinion, the addition of deep hypothermic circulatory arrest has been a significant advance.  相似文献   
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Resection of inferior vena cava tumor thrombi from renal cell carcinoma.   总被引:1,自引:0,他引:1  
Renal cell carcinoma is an unusual cancer with the propensity to invade not only the renal vein but to propagate into the inferior vena cava (IVC) as a tumor thrombus. Experience has recently confirmed that MRI will be valuable in evaluating the extent of the tumor thrombus. The surgical techniques used to remove the thrombus are dependent on the extent of the cancer. For lesions involving the infrahepatic IVC, only proximal and distal control of the IVC are necessary. For a thrombus involving the intrahepatic IVC, isolation of the suprahepatic IVC, hepatic circulation, and infrahepatic IVC or cardiopulmonary bypass can be used. For the large thrombus in the supradiaphragmatic IVC or atrium, cardiopulmonary bypass either with or without deep hypothermic circulatory arrest is appropriate. In a review of 48 cases with renal cell carcinoma with IVC tumor thrombi, the tumor thrombus was removed intact in 58 per cent and in multiple fragments ("piece-meal") in 42 per cent of the patients. Cardiac bypass has been used in 26 cases with 22 undergoing deep hypothermic circulatory arrest. The postoperative mortality of 48 cases between 1965 and 1987 was 4 per cent. Removal of the most complicated and extensive renal cell carcinoma tumor thrombi is now technically feasible. In patients with large tumor thrombi, however, the ultimate outlook remains poor in the absence of effective systemic adjuvant therapy.  相似文献   
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The objective of the present study is to propose guidelines to ensure safe practice in teaching centres while allowing endoscopic sinonasal surgery (ESS) training to proceed. A prospective complications audit of ESS procedures was undertaken over a 5‐year period (January 1996–December 2000). The results have been used to form specific guidelines for safe and effective ESS training. A total of 500 patients underwent ESS during the 5‐year period. The senior author was the main surgeon in 55% of cases with the trainee observing or assisting. A supervised trainee was the main surgeon in 45% of cases. The overall complication rate was 1.2% (n = 6) (i.e. 0.7% for the 815 procedures performed). These were all minor complications. We encountered no major complications in 500 patients over the 5‐year period. This audit shows that training need not compromise patient safety provided it is phased and structured. We propose appropriate phases and suggest the minimum requirements for units involved in ESS training.  相似文献   
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