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1.
C F Heyns  M L de Kock  C J Deale 《Urology》1990,35(3):247-249
A fifteen-month-old boy with ambiguous external genitalia was found to have a 46XX karyotype, an ovotestis in the right labioscrotal fold, and an absent left gonad. He also had a rudimentary uterus and fallopian tubes and a blind-ending vagina lined with squamous epithelium. These features are compared with those more commonly found in true hermaphroditism.  相似文献   
2.
Tissues were obtained from 387 male pig fetuses ranging from 60 to 120 days of gestation. The relative wet mass and water content of the gubernaculum increased during and decreased after the period of testicular descent. The extracellular glycosaminoglycans (GAG) were assayed to determine whether these polyanionic macromolecules are responsible for the increased water content of the gubernaculum. The total GAG/wet tissue mass in the gubernaculum decreased during and increased after descent, while the total GAG/dry mass decreased during and after descent, indicating an accumulation of water during descent, with a loss of water and an increase in less hydrated tissue components after descent. The major GAG fraction in the gubernaculum was dermatan sulfate, but the percentage hyaluronate in the gubernaculum was two times higher than in striated muscle or umbilical cord, indicating that this GAG fraction may be responsible for the increased water content of the gubernaculum, which probably serves to dilate the inguinal canal and scrotum, thus facilitating descent.  相似文献   
3.
Epidemiological data from the United States of America (USA) indicate that the incidence and mortality of prostate cancer is higher among Black African-American men (AAM) than among White (Caucasian) American men (CAM). Earlier studies suggesting that prostate cancer is relatively rare among indigenous Black men in Africa are probably flawed by underreporting because recent studies indicate that the incidence rates among Black men are similar to those of White men living in Africa. The higher incidence of prostate cancer among AAM has been ascribed to racial differences in genetic susceptibility, dietary factors, or androgen metabolism. However, it may also be due to registration artefacts because in Africa the reported incidence rates of prostate cancer in different countries correlate directly with the per capita gross national product, suggesting improved access to medical facilities is responsible for higher reported incidence rates.

The greater prostate cancer mortality among AAM may result from higher tumour grade and stage and higher serum PSA at presentation, but it has also been suggested that prostate cancer is biologically more aggressive in AAM than in CAM. However, recent studies indicate that tumour grade and stage and serum PSA at presentation are similar in the races, with no difference in survival after multivariate analysis controlling for pretreatment cancer severity. This suggests that the higher prostate cancer mortality among AAM results from socio-economic factors and limited access to healthcare. Black men living inside as well as outside of Africa still tend to present with locally advanced or metastatic prostate cancer due to lack of early detection programmes.  相似文献   

4.
Among the anomalies of testicular descent exstrophy of the testis appears to be the most rare. We describe a full-term male newborn with the right testis and spermatic cord prolapsed from a skin defect at the neck of the scrotum. The cause of the anomaly is unknown.  相似文献   
5.
We analyzed 3-dimensional (3D) computed tomographic images of the pelvicaliceal system obtained in 25 patients after opacification of the collecting system by retrograde ureteric or intravenous (IV) infusion of sodium iothalamate. 3D images were reconstructed using the data from nonoverlapping 5-mm sections taken on an Elscint 2400 scanner. Factors contributing to poor image quality were: artifacts caused by contrast in the collecting tubules, underfilling or overdistension of the pelvicaliceal system with contrast, movement of the patient and severe hydronephrosis. Satisfactory 3D images of the pelvicaliceal system can be obtained by retrograde ureteric infusion of 5% w/v sodium iothalamate at 20 cm H2O, or by IV injection of 50 ml of 70% w/v sodium iothalamate. Abdominal compression should be applied 10-15 min after the IV injection of contrast, and the computed tomographic examination should commence 20-30 min after the injection. It is imperative that the patient lie completely still and breathe normally to avoid movement of the kidneys. 3D computed tomographic imaging of the pelvicaliceal system may become a valuable adjunct to the preoperative planning and performance of percutaneous nephrolithotomy.  相似文献   
6.
The role of the gubernaculum during testicular descent was investigated in 115 male pig fetuses ranging from 68 to 109 days of gestation. Descent of the testis through the inguinal canal occurred between 77 and 94 days. There was a marked increase in the total and relative wet mass as well as the wet/dry mass ratio of the gubernaculum, denoting an increase in the water content of this structure during descent of the testis. Similar changes were not seen in other fetal tissues. Asymmetrical descent of the testes occurred in seven of the 40 fetuses between 81 and 92 days of gestation. Descended testes had gubernacula with a greater relative wet mass than the gubernacula of undescended testes. These findings indicate that the increase in mass of the gubernaculum plays an important part in testicular descent. An increase in both the DNA content (hyperplasia) and the RNA/DNA ratio (hypertrophy) was noted in the gubernaculum during descent of the testis. Hyperplasia in the gubernaculum occurred at a rapid rate initially and ceased after the completion of descent. Hyperplasia was also seen in the testis and epididymis, but occurred at a slower rate initially, with a rapid acceleration after the completion of descent. Cellular hypertrophy was not noted in the testis and epididymis, but did occur in umbilical cord tissue. If gonadotropins acting via androgen secretion by the testis provide the stimulus for these changes, the observed difference in response between the gubernaculum and testis could be due to a difference in end-organ sensitivity. However, it is also possible that some unidentified non-androgenic gubernaculotropin, possibly secreted by the fetal testis, provides the stimulus for gubernacular growth.  相似文献   
7.
A method for washing platelets by albumin density gradient separation has been modified to prepare platelet rich plasma of thrombocytopenic patients for platelet aggregation studies. The concentration procedure, consisting of centrifuging platelets into a specific gravity gradient between plasma and 40-45% aqueous solution of bovine albumin, does not affect platelet aggregation adversely. Platelet aggregation in eight patients with chronic idiopathic thrombocytopenic purpura was determined by this method. On the basis of the results the patients could clearly be divided into two groups: four patients with normal aggregation and four with a qualitative platelet defect. In contrast to the other patients, the group with an in vitro platelet functional defect all had more prolonged bleeding times and the presence of a serum antiplatelet antibody.  相似文献   
8.
Twelve mathematic methods used to calculate the mean platelet survival time were compared by determining the "goodness of fit" of the models to the platelet survival curves of 15 reference subjects and 54 patients. Platelets were labeled with [111In]oxine. The linear (LN), exponential, weighted mean, multiple hit (MH), Dornhorst (DH), Meuleman (ML), alpha order (AO), and polynomial (PO) mathematic models were investigated. The goodness of fit for the exponential model was determined by the nonlinear least squares method (EP), and also by the linear least squares method on logarithmically transformed data (EX) as is recommended. The modified weighted mean (MWM) and the usual weighted mean method (WM) obtained with these exponential models were tested. The Dornhorst (DH10) and Meuleman (ML10) models, where the potential age-dependent platelet survival times were kept constant at 10 days, were also evaluated. The goodness of fit results, expressed as % s.d. indicated that the LN (5.2%), EX (5.0%), EP (4.4%), WM (3.7%), DH10 (3.7%), and ML10 (3.7%) models all fitted the data significantly worse than the MWM, MH, DH, ML, AO, and PO models (range 3.2-3.3%). The mean platelet survival time determined with the MH model differed significantly from the results with the DH, ML, and AO models. The results of mean platelet survival time calculated with different mathematic models cannot, therefore, be compared directly. The models that fitted the platelet survival curve well varied slightly in sensitivity to noise as is indicated by the coefficient of variation of the mean platelet survival time estimates for the reference subjects (range 7.9-12.0%). Fitting data to at least two mathematic models has definite advantages. Data on which the calculations are based are probably invalid if the following are true: (a) if the mean platelet survival time estimated with the alpha order model is shorter than that estimated with the EP, MWM, or MH models, or (b) the mean platelet survival time estimated with either the DH, ML, AO, or PO models, is longer than the LN, MWM, or MH estimate of the mean platelet survival time. We conclude that the mean platelet survival time can be reliably estimated by fitting the data to either the MWM method (if limited computing facilities are available) or the MH model. Confidence in the result will be increased if considered in conjunction with the finding obtained with one other model; in those cases where the platelet survival time is very short, the alpha order model is recommended.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
9.
OBJECTIVE: To determine whether serum prostate-specific antigen (PSA) can be reliably used to predict the absence or presence of skeletal metastases on the bone scan in patients with adenocarcinoma of the prostate. METHODS: We studied 450 consecutive men presenting with adenocarcinoma of the prostate between 1991 and 1995. Serum PSA was measured by the Hybritech Tandem-R monoclonal immunoradiometric assay and bone scanning was performed with 99m-technetium-labelled methylene diphosphonate. In total, 46 patients were excluded for one or more of the following reasons: serum PSA not available; radionuclide bone scan inconclusive; histology of the prostate other than adenocarcinoma; hormonal or other therapy given prior to obtaining the serum PSA and/or bone scan. RESULTS: Of the 404 patients included, 43% had poorly differentiated (grade 3), 74% had locally advanced (stages T3-4) tumours and 50% had skeletal metastases. The mean and median serum PSA were 348 and 52 ng/ml, respectively, and 77% of the patients had a serum PSA >20 ng/ml. The negative predictive value (for the absence of metastases on bone scan) of a serum PSA <20 ng/ml was 87% for the whole group of patients, 92, 94 and 70% for grade 1, 2 and 3 tumours, and 95, 83 and 50% for stage T1-2, T3 and T4 tumours, respectively. The positive predictive value (for the presence of metastases on bone scan) of a serum PSA >100 ng/ml was 80% for the whole group of patients. CONCLUSIONS: In patients presenting with adenocarcinoma of the prostate, serum PSA alone is not sufficiently reliable to predict the absence or presence of metastases on the radionuclide bone scan. In patients with grade 3 and clinical stage T3-4 tumours, a bone scan should be obtained for accurate staging, regardless of the serum PSA value.  相似文献   
10.
A number of androgen effects on epithelial cells may be mediated by androgen-regulated paracrine factors produced by underlying mesenchymal cells. In previous studies we demonstrated that prostatic stromal cells and testicular peritubular cells, derived from immature rats, produce mediators of androgen action with identical effects on Sertoli cells. In the present paper we further compared the morphological and functional characteristics of both mesenchymal cell types. Cultured prostatic stromal cells and testicular peritubular cells look identical under phase-contrast microscopy, share the ability to form tubular structures and "balls" when cocultured with Sertoli cells, and contain proteins immunoreactive with an antiserum against alpha-smooth muscle isoactin. Two-dimensional gel electrophoresis shows that the pattern of proteins produced by both cell types is nearly identical. Conditioned media from stromal and peritubular cells contain a factor that stimulates transferrin and cGMP production in Sertoli cells. The behavior of the active principle in the media from both cell types is comparable. On reverse-phase HPLC the elution profile of this factor is comparable for media from both cell types. In conclusion, these data point to a striking similarity in the morphological and functional characteristics of mesenchymal cells cultured from the prostate and testis.  相似文献   
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