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PURPOSE: To report anterior ischemic optic neuropathy associated with systemic hypotension in a patient undergoing continuous ambulatory peritoneal dialysis. METHODS: Case report. A 58-year-old man undergoing continuous ambulatory peritoneal dialysis developed painless blurred vision in both eyes and bilateral optic disk swelling with an altitudinal field defect in the left eye. Twenty-four-hour ambulatory blood pressure monitoring was requested in addition to other routine investigations. RESULTS: Routine blood pressure measurement in the clinic was 130/86 mm Hg, but ambulatory blood pressure monitoring demonstrated pronounced early morning hypotension with individual readings as low as 91/41 mm Hg. CONCLUSIONS: Renal dialysis can render patients hypotensive, and this may be associated with anterior ischemic optic neuropathy. The overnight drop in blood pressure may not be appreciated with routine blood pressure measurement. Therefore, 24-hour ambulatory blood pressure monitoring should be considered when investigating patients with suspected anterior ischemic optic neuropathy who are undergoing renal replacement.  相似文献   
13.
Hospitals seeking to become more aggressive often are tempted to introduce programs prematurely. Using the example of a geriatric services program at a large hospital, the authors illustrate the dangers of neglecting internal marketing and offer recommendations for ensuring internal coordination prior to introduction of a product externally.  相似文献   
14.
OBJECTIVE: We characterized insulin secretion and glucose disposal in a large unselected group of women, encompassing the full spectrum of glucose tolerance in pregnancy, and related the findings to maternal obesity. STUDY DESIGN: Intravenous glucose tolerance and first-phase insulin response were measured at about 32 weeks' gestation in 690 unselected pregnancies. The women were designated as "lean," "normal," or "obese" on weight-for-height criteria. RESULTS: The distribution of insulin response was bimodal, but there was no corresponding dichotomy in maternal glucose disposal rate. Insulin response was greatest and glucose disposal rate slowest in obese women. In general, "poor" glucose tolerance was associated with relatively low insulin output. It was not possible to identify any cluster of women, obese or otherwise, in whom poor glucose tolerance was specifically associated with an unusually high insulin response. CONCLUSION: The data indicate that the distribution of glucose tolerance in pregnancy is a continuum. Glucose intolerance represents one end of that spectrum and is attributable to insufficient insulin secretion. This relative insufficiency is most frequent with maternal obesity.  相似文献   
15.
Primary mucoepidermoid carcinomas of the skin are extremely rare tumors. We describe a primary cutaneous mucoepidermoid carcinoma arising in the right ear (posterior mid helix) of a 66-year-old white man. The tumor was 0.6 cm in diameter, ulcerated and nonencapsulated. No other tumors were found in the patient. Histologically the tumor showed the characteristics of a "low grade" mucoepidermoid carcinoma, consisting of lobules of polygonal cells with vesicular nuclei. In the center of the lobules were large vacuolated cells (goblet cells). Transitions between the two cell populations were present throughout the tumor. An epidermal attachment of the tumor, as well as epidermal dysplasia, predominantly at the acrosyringium was present, consistent with the theory of sweat duct histogenesis of these tumors. Immunoperoxidase staining showed positivity for epithelial membrane antigen, keratin and carcinoembryonic antigen. The latter was predominantly positive in the goblet cells. Cutaneous metastasis of mucoepidermoid carcinomas with epidermal attachment has been reported. Our case showed only ear involvement and follow-up at 8 months has revealed no evidence of recurrence. These findings are consistent with the diagnosis of primary cutaneous mucoepidermoid carcinoma.  相似文献   
16.
OBJECTIVE: Patients affected by schizophrenia show deficits in both visual perception and working memory. The authors tested early-stage vision and working memory in subjects with schizotypal personality disorder, which has been biologically associated with schizophrenia. METHOD: Eleven subjects who met DSM-III-R criteria for schizotypal personality disorder and 12 normal comparison subjects were evaluated. Performance thresholds were obtained for tests of visual discrimination and working memory. Both form and trajectory processing were evaluated for each task. RESULTS: Subjects with schizotypal personality disorder showed intact discrimination of form and trajectory but were impaired on working memory tasks. CONCLUSIONS: These data suggest that subjects with schizotypal personality disorder, unlike patients affected by schizophrenia, have relatively intact visual perception. Subjects with schizotypal personality disorder do show specific deficits on tasks of comparable difficulty when working memory demands are imposed. Schizotypal personality disorder may be associated with a more specific visual processing deficit than schizophrenia, possibly reflecting disruption of frontal lobe systems subserving visual working memory operations.  相似文献   
17.
Leavitt  SA; DeAngelo  AB; George  MH; Ross  JA 《Carcinogenesis》1997,18(11):2101-2106
Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.   相似文献   
18.
Long-chain polyunsaturated fatty acids (LCP) are thought to be required for optimal nervous system development in the newborn. A commercial milk formula containing LCP (Aptamil-LCP) with a fatty acid profile closely resembling breast milk, has recently been introduced for term infants. The absorption of fatty acids in term infants was examined in a double-blind randomized controlled trial comparing Aptamil-LCP ( n = 20) and standard Aptamil ( n = 20). Formula-fed newborn infants were studied from birth for 14 d. Fat balances (3 d) were performed from d 10. A 3-d stool collection was performed from d 10 in a parallel breastfed group ( n = 21). Plasma samples were taken on d 6. Median fat excretion (mg kg−1) was 897.1, 615.0 and 355.2 with Aptamil, Aptamil-LCP and breastfeeding, respectively. The median total fat absorption coefficient in Aptamil-LCP-fed infants was higher than in those fed standard Aptamil ( p < 0:01). These findings were accounted for by differences in the excretion and absorption of long-chain saturated fatty acids (C14:0, C16:0 and C18:0). Higher fat excretion was associated with bulkier and firmer stools. Only trace amounts of LCP were detected in the stools of all groups. This accounted for less than 4% of dietary intake in Aptamil-LCP-fed infants. No differences in the utilization of LCP from Aptamil-LCP and breast milk feeding were apparent. Plasma phospholipid fatty acid composition data reflected differences in dietary LCP intake. Thus, PL LCP levels were highest in the breastfed infants and lowest in the Aptamil-fed infants, with values for the Aptamil-LCP-fed group falling in between.  相似文献   
19.
Low-grade astrocytomas in children: evolving management strategies   总被引:2,自引:0,他引:2  
Developments in imaging and in neurosurgical techniques over the past decade have substantially altered the management of children with low-grade astrocytoma. Indications for surgery have become more clearly defined, and a larger proportion of children undergo complete or subtotal resection than in the past. Fewer receive adjuvant therapy, even though the options in this regard are more numerous now and theoretically likely to result in less morbidity than conventional external beam radiotherapy.

This review will address in particular the correlations between location, imaging appearance, and behavior that need to be more widely appreciated, and present recommendations regarding the management of these tumors.  相似文献   

20.
Advances in pediatric liver and intestinal transplantation   总被引:7,自引:0,他引:7  
BACKGROUND: Significant progress has been made with liver and intestinal transplantation in pediatric patients. Shortage of whole-organ cadaveric grafts has resulted in a high mortality rate for children awaiting transplantation. New surgical procedures such as split-liver transplantation and living-related liver transplantation have evolved over the last decade to maximize donor utilization in pediatric patients. METHODS: In this article we review the current indications and contraindications for liver and intestinal transplantation in children, the surgical innovations to expand an exceedingly small cadaveric liver pool, postoperative management, and the impact on patient and graft survival. RESULTS: Reduced-size liver transplantation provides children with much needed small grafts; however, split-liver transplantation may eliminate the need for reduced-size and living-related liver transplantation except in urgent situations. CONCLUSION: Liver transplantation is a durable procedure that provides excellent long-term survival. The use of living-related and split-liver transplantation has dramatically reduced the waiting periods for children and improved survival. In the past decade significant progress has been made with intestinal transplantation owing to improvements in surgical technique, immunosuppressive agents, and early identification and treatment of postoperative complications.  相似文献   
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