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991.
A Adesokan PA Adegboyega DF Cowan J Kocurek DE Neal 《Canadian Metallurgical Quarterly》1997,80(11):2120-2127
BACKGROUND: Males with congenital adrenal hyperplasia may develop bilateral testicular masses in early adult life. These are not malignant and generally regress with corticosteroid therapy. The authors report a case occurring in a 44-year-old man with associated seminoma and myelolipoma in an undescended testis. METHODS: The testicular tumors were analyzed by histologic, flow cytometric, and ultrastructural techniques. RESULTS: The tumors in both testes were comprised of polygonal cells with abundant granular eosinophilic cytoplasm, occasionally with brown (lipochrome) pigment and round nuclei of various sizes with prominent nucleoli. These cells were grouped into nodules by dense and sometimes thick fibrous trabeculae in the right testis. The areas corresponding to the fibrous trabeculae in the left (intraabdominal) testis were replaced by mixture of hematopoietic (myeloid) and fatty tissue in various proportions characteristic of myelolipoma. The left testis also had a well demarcated tumor that was diagnostic of seminoma. Electron microscopy demonstrated abundant smooth endoplasmic reticulum, a moderate number of mitochondria with tubulovesicular cristae, lipid droplets, and lipofuscin granules in the polygonal cells. No Reinke's crystals were observed. The patient received corticosteroids for his adrenocorticoid deficiency and also underwent external beam irradiation to the retroperitoneum for seminoma. CONCLUSIONS: This case illustrates an unusual presentation of a testicular tumor in a patient with the adrenogenital syndrome as well as with myelolipoma and seminoma in a cryptorchid testis. The possibility of an associated neoplasm that could be potentially fatal should be considered whenever a testicular tumor of the adrenogenital syndrome continues to grow despite adequate hormonal treatment. 相似文献
992.
PURPOSE: Prostate-specific antigen (PSA) is extensively used in case selection and outcome evaluation after treatment of clinically localized prostate cancer. Careful case selection can have a profound impact on pathologic findings and ultimate outcome. In addition, salvage treatment is frequently initiated at the time of biochemical relapse rather than clinical recurrence. Consequently, patterns of failure can be significantly altered compared to previous times when PSA was not available. To better understand the impact of PSA on pathologic findings, outcome, and salvage treatment, we reviewed our experience in the PSA era with clinical Stage T1-2 prostate cancer treated with radical prostatectomy. METHODS AND MATERIALS: Between 1987 and 1993, 423 cases could be identified with clinical Stage T1-2 prostate cancer treated with radical prostatectomy. The distribution of cases by pretreatment PSA levels was as follows: < or = 4 ng/ml (18%), 4-10 ng/ml (42%), 10-20 ng/ml (21%), > 20 ng/ml (14%), and unknown (5%). The median pretreatment PSA level for the entire group was 8.0 ng/ml. Sixteen patients received adjuvant or neoadjuvant androgen suppression and 13 received postoperative radiotherapy. Only 31 patients (7%) had pathologically positive pelvic lymph nodes. The overall margin involvement rate was 46%. Fifty-three percent of patients had surgical Gleason scores > or = 7, and 65% had extracapsular extension. The median follow-up time was 41 months. RESULTS: The projected overall survival at 7 years after surgery was 90%. The 5-year clinical relapse-free survival rate was 84%. At 5 years, the local control and distant failure rates were 92% and 91%, respectively. Biochemical relapse was defined as a detectable or rising PSA level after prostatectomy. The 5-year biochemical relapse-free survival (bRFS) rate was 59%. The 5-year RFS was 88% in patients with preoperative PSA levels < or = 4, 62% for 4-10, 48% for 10-20, and 31% for > 20. Combining the two independent preoperative variables, iPSA and biopsy GS (bGS), two risks groups were defined: low risk [initial PSA (iPSA) levels < or = 10.0 and bGS < or = 6] and high risk (iPSA levels > 10.0 ng/ml or bGS > or = 7). The 5-year bRFS rate for the low-risk cases was 81% vs. 40% for high-risk cases (p < 0.001). On multivariate analysis, three factors independently predicted biochemical relapse: iPSA levels (p = 0.005), Gleason score from the surgical specimen (sGS) (p = 0.002), and positive surgical margins (p < or = 0.001). The 5-year bRFS rates for margin positive vs. margin negative patients were 37% vs. 78%, respectively. The 5-year bRFS rates for GS > or = 7 vs. GS > or = 6 were 42% vs. 80%, respectively. All clinical relapses were accompanied by a rise in PSA. In patients who manifested biochemical failure followed by a clinical failure, the median interval between the PSA rise and clinical failure was 19 months (range 7-71). Margin involvement was the only independent predictor of local failure (p = 0.019). The 5-year local failure-free survival for negative margin cases was 96% vs. 87% for positive margin cases (p = 0.012). Lymph node (LN) involvement and high-risk group were the two independent predictors of distant failure. The 5-year distant failure-free survival for negative LN cases was 94% vs. 67% for positive LN cases (p < 0.001). The 5-year distant failure-free survival for low-risk cases was 97% vs. 85% for high-risk cases (p = 0.005). For the 124 patients failing biochemically, 85 were observed and 39 were treated either with radiation or androgen deprivation. With a median follow-up of 32 months, the clinical disease relapse-free survival was 79% for the treated patients vs. only 32% for the patients observed (p < 0.001). CONCLUSION: Pretreatment PSA is the most potent clinical factor independently predicting biochemical relapse, thereby allowing markedly better case selection. Achieving negative margins, even in relatively advanced disease, provides excellent lon 相似文献
993.
Root surface caries is prevalent in patients with both treated and untreated periodontal disease. The major etiologic factor has been identified as microbial plaque. In periodontally treated patients, significantly higher root caries prevalence and incidence have been found in patients with high levels of Streptococcus mutans and Lactobacilli in saliva. Reducing the levels of S. mutans and Lactobacilli in saliva may lower the risk of root caries development. The purpose of this investigation was to determine the effect of an oral enzymatic rinse on the salivary counts of S. mutans and Lactobacilli in periodontally treated patients. Fifteen adult subjects participated in a double-blind, cross-over designed clinical trial. Each subject had previously undergone comprehensive periodontal therapy and had been maintained on a regular program of supportive periodontal therapy. Paraffin-stimulated whole saliva was collected from each participant. Each subject was then randomly given either the enzymatic rinse product or a control rinse and instructed to rinse with one tablespoonful twice a day for 2 weeks, after which saliva samples were taken. After a washout period, salivary samples were again taken, and the subjects received the alternate rinse product. Two weeks later, final salivary samples were taken. The salivary samples were serially diluted and incubated aerobically on selective culture media. S. mutans and Lactobacilli were counted on the basis of colonial morphology. Pretreatment and posttreatment salivary counts of S. mutans and Lactobacilli were analyzed using the Wilcoxon matched-pairs signed-rank test at the 5% level of significance. Analysis of data revealed that neither the test nor the control rinse significantly lowered salivary counts of either species in the sample population. 相似文献
994.
MS Sweeney DJ Young OH Frazier PR Adams MO Kapusta MP Macris 《Canadian Metallurgical Quarterly》1997,64(2):384-7; discussion 387-9
BACKGROUND: Because traumatic aortic transection is associated with high mortality rates, great debate exists about the appropriate operative technique for treatment of patients who have acute traumatic aortic transection. METHODS: To determine the safety and efficacy of the "clamp-sew" method, we retrospectively reviewed our 8-year experience treating 75 patients who had aortic injuries secondary to blunt trauma. Seventy-one of these patients were treated surgically. The clamp-sew method was used in all of these operations. RESULTS: Aortic cross-clamp time averaged 24 minutes (range, 14 to 36 minutes), with 4/71 having times in excess of 30 minutes. One patient (clamp time, 28 minutes) became paraplegic. Significant associated injuries were seen in 51/75 patients (48/71 patients with operation), including intrathoracic (35 patients), orthopedic (28 patients), intraabdominal (24 patients), and central nervous system (17 patients) damage. No patient died within 24 hours of operation. Overall 30-day mortality was 12% (9/75), with 7/9 having two or more aforementioned associated injuries. Of these 7, 5 had central nervous system injuries. Two of 9 died within 30 days without two or more associated injuries: 1 Jehovah's Witness of low hemoglobin, and 1 patient of sepsis. CONCLUSIONS: Although any of several maneuvers may be appropriate in managing traumatic aortic injuries, the simple "clamp-sew" technique is a safe and effective method for the treatment of traumatic aortic transections. 相似文献
995.
996.
997.
998.
A polyneuropathy is characterized by a symmetrical distribution of sensory or motor abnormalities, more pronounced distally than proximally and usually more evident in the lower than in the upper limbs. Polyneuropathies may be classified on the basis of (a) clinical picture: acute/subacute/chronic, sensory/motor/autonomous, axonal degeneration/segmental demyelinization, and (b) cause: metabolic disorder, deficiency, infection, auto(dys)immunity, hereditary and toxic/iatrogenic polyneuropathy, with idiopathic polyneuropathy as the remaining group. Damaged nerves may recover as the result of spontaneous remyelinization and axonal regeneration. Treatment is particularly successful in immunomediated neuropathies. Withdrawal is often successful in intoxications and suppletion in deficiencies. Even if no treatment is possible, the diagnosis is important: the patient can be taught to accept his disease and the prognosis can be determined, in connection with possible handicaps. 相似文献
999.
SA Kidd PA Lancaster JC Anderson A Boogert CC Fisher R Robertson DM Wass 《Canadian Metallurgical Quarterly》1997,11(2):200-213
We conducted a retrospective cohort study to assess the risk of amniocentesis in twin pregnancy for adverse outcomes. The study base consisted of women who had an amniocentesis performed during twin pregnancy and a comparison representative sample of women who carried a twin pregnancy, but did not have invasive prenatal diagnosis. The 227 women in each of the exposed and non-exposed groups were residents of the state of New South Wales, Australia, over the period 1980-92, and were matched on maternal age and period of the infant's birth. Nearly 10% of twin pregnancies among the women having an amniocentesis were affected by a stillbirth, and the stillbirth rate among exposed fetuses (5.3%) was nearly twice as high as among non-exposed fetuses (3.1%). After adjustment for confounding and excluding abnormalities, there was a non-significant elevated relative risk of stillbirth after exposure to amniocentesis. The analysis by type of amniocentesis (with and without methylene blue dye) was limited by small numbers, but the burden of risk was primarily among women who had dye exposure during amniocentesis (relative risk = 3.64, 95% confidence interval = 1.15, 11.48). This increase remained after adjusting for confounding, although the confidence interval was wide. In conclusion, we were unable to establish with certainty whether an increased risk of stillbirth could be ruled out among women who had any type of amniocentesis in twin pregnancy. 相似文献
1000.
LM Kelley JP Walker GL Wing PA Raskauskas CL Schepens 《Canadian Metallurgical Quarterly》1997,28(7):565-569
BACKGROUND AND OBJECTIVE: The goal was to utilize ultrasound-guided cryotherapy as an immediate, low-risk, noninvasive, precise method of treating retinal tears obscured by vitreous hemorrhage. PATIENTS AND METHODS: Eleven patients with sudden onset of vitreous hemorrhage were referred for diagnosis and management. Ophthalmoscopy with scleral depression was unsuccessful at localizing peripheral retinal tears, and all of the patients were examined with ultrasound using the techniques of standardized echography. The cryoprobe was positioned for cryotherapy using both transverse and longitudinal B-scan approaches following the indentation of the globe as it appeared on the oscilloscope. RESULTS: On follow-up examination after the vitreous hemorrhage cleared, 10 of the 11 tears were examined by ophthalmoscopy and were thought to have been adequately treated. One patient had a retinal detachment after remaining stable for 3 months. Two patients were treated with laser to enhance the cryotherapy seal. One patient was observed by another physician and underwent vitrectomy due to vitreous hemorrhage that persisted 2 months following cryotherapy. After vitrectomy, the physician reported a successful cryotherapy reaction at the treated tear. One final patient in the series required vitrectomy and scleral buckle before the hemorrhage had cleared, and the treatment did not appear to be complete. CONCLUSION: Ultrasound-guided cryotherapy provides a noninvasive, inexpensive treatment alternative for retinal tears obscured by vitreous hemorrhage. 相似文献