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91.
Recent data suggest that tumor cells contaminating reinfused bone marrow may contribute to relapse in patients undergoing autologous bone marrow transplantation. Purging strategies that are able to remove these contaminating tumor cells need to be developed. This study describes how electroporation (EP) can be used to improve intracellular delivery of synthetic antisense oligodeoxynucleotides (ODNs), thereby enhancing their ability to suppress a target protein. Antisense ODNs that were introduced into cells by EP led to immediate suppression of targeted c-myc protein; this was associated with rapid cell death in the diffuse histiocytic lymphoma, U937; Burkitt's lymphoma, ST486; breast carcinoma, MCF-7; and Ewing's sarcoma, CHP-100, cell lines. Electroporation was found to have little or no detrimental effect on cells responsible for murine hematopoietic long-term reconstitution as determined from in vivo competitive repopulation studies. Using human c- myc-directed antisense ODNs as a model for the application of this approach to bone marrow purging, selective killing of human lymphoma U937 cells relative to normal human bone marrow cells was shown in cell mixing studies. In vivo studies were performed in which a survival advantage was shown for athymic mice that were inoculated with antisense-treated U937 cells as opposed to control cells. These studies suggest that EP of bone marrow may be of use in enhancing intracellular delivery of a variety of molecular/pharmaceutical agents. Taken together, these data suggest that the use of electroporation to enhance delivery of antisense ODNs is a promising new approach towards ex vivo bone marrow purging.  相似文献   
92.
Impaired alveolar gas exchange in acute pancreatitis   总被引:3,自引:0,他引:3  
We evaluated the alveolar–arterial oxygen difference (A-a) and the ratio between Pao2 and the fractional concentration of inspired oxygen (P/F) in acute pancreatitis. Eleven patients had mild uncomplicated disease, six showed acute abdominal fluid collections, six had acute abdominal collections and asymptomatic x-ray lung involvement, three presented transient dyspneic episodes, and four had severe acute pancreatitis requiring prolonged oxygen therapy. In the uncomplicated disease, respiratory function was normal; in the six patients with abdominal collections only, A-a increased by 50% and P/F decreased by 20–30%; in the six patients with abdominal collections and asymptomatic x-ray lung involvement, A-a increased by 50–70% and P/F decreased by 40%; the three patients with dyspneic episodes showed a twofold increase in A-a and a 40% decrease in P/F; the four patients with severe pancreatitis had a two- to threefold increase in A-a and a 40–50% decrease in P/F. Hence respiratory function is normal only in uncomplicated pancreatitis; in the presence of complications, disturbance of gas exchange always occurs, requiring careful control and treatment.  相似文献   
93.
Lai  ME; Farci  P; Figus  A; Balestrieri  A; Arnone  M; Vyas  GN 《Blood》1989,73(1):17-19
The high endemicity of hepatitis B virus (HBV) infection and liver disease in Sardinia led us to assess the occurrence of HBV DNA in 1,411 sera of two selected groups of hepatitis B surface antigen (HBsAg)- negative blood donors: 793 with abnormal serum alanine aminotransferase (ALT) and 618 with normal serum ALT values (determined during routine testing of their blood donation). HBV DNA sequences were detected by dot-blot hybridization in 68 of 793 subjects (9%) with abnormal ALT but only in three of 618 subjects (0.5%) with normal ALT. HBV-core antibody (anti-HBc) was detected in 338 of 793 subjects (43%) with abnormal ALT as well as in 125 of 618 subjects (20.2%) with normal ALT. Among the 71 subjects positive for serum HBV DNA, 22 (31%) were positive for anti- HBc, while 49 (69%) were negative for all serologic markers of HBV infection. Thus, a high frequency of anti-HBc in apparently healthy HBsAg-negative individuals and a high prevalence of serum HBV DNA in the absence of immunologic markers of HBV infection suggest the existence of genetic variants of HBV that may be responsible for some of the presumed NANB hepatitis encountered in Sardinia and possibly other areas of high endemicity for HBV.  相似文献   
94.
Scillian  JJ; McHugh  TM; Busch  MP; Tam  M; Fulwyler  MJ; Chien  DY; Vyas  GN 《Blood》1989,73(7):2041-2048
There is evidence that some human immunodeficiency virus (HIV)-infected individuals have prolonged periods of seronegativity. A flow cytometric immunoreactive bead (IRB) assay is described for quantitative, simultaneous, and early detection of antibodies to HIV. Polystyrene beads of four diameters, each size coated with a different HIV recombinant DNA-produced protein (p24, p31, gp41, or gp120), bound anti- HIV antibodies detected with fluorescent antiglobulin. The IRB assay was performed on a panel of blood donor samples, many giving consistently false-positive enzyme immunoassay (EIA) and indeterminant Western blot (WB) results. The IRB assay proved as sensitive and more specific than currently licensed EIA and WB tests. Results on serial samples from eight HIV-infected individuals indicated that quantitation of anti-p24 by IRB assay may be useful in monitoring disease progression. Sequential pre- and post-EIA seroconversion sera from 35 HIV-infected homosexual men were tested by the IRB assay using IgM- and IgG-specific fluorescent probes. All 35 cases were IRB assay positive for at least one rDNA-p either before (17 of 35, 49%) or at the time of EIA positivity. Eleven cases (31%) initially had only IgM anti-HIV, primarily to gp41 (17%). In two individuals, the IgM response was detected at least 18 months before EIA seroconversion. The IRB assay is a widely applicable analytic procedure, potentially useful in pretransfusion anti-HIV screening of blood.  相似文献   
95.
BACKGROUND & AIMS: Ontogeny of colonic Cl- transport and its regulation has been characterized inadequately. The aim of this report was to study developmental changes in Cl- transport in primary cultures of rabbit distal colonocytes. METHODS: Colonocytes from newborn (7-9 days old), weanling (25-28 days old), and adult (6 months old) rabbits were cultured for 24 hours on a collagen IV matrix, and Cl- transport was measured using the fluoroprobe 6-methoxyquinolyl acetoethyl ester. RESULTS: Cl- permeabilities were dependent on [Cl-]o with maximal rates (in millimoles per liter per second) at [Cl-]o = 75 mmol/L (newborns; 0.15 +/- 0.04; weanlings; 0.2 +/- 0.02; and adults, 0.32 +/- 0.06). Influx was inhibited significantly by the Cl- channel (50 mumol/L diphenylamine-2-carboxylate) and the Na(+)-K(+)- 2Cl- cotransport (10 mumol/L furosemide) inhibitors. The adenosine 3',5'-cyclic monophosphate (cAMP)-dependent secretagogues, prostaglandin E1 (1 mumol/L), forskolin (1 mumol/L), and 8-bromo-cAMP (100 mumol/L), and the protein kinase C activator, phorbol 12-13 dibutyrate (1 mumol/L), increased Cl- influx significantly in all groups with adults showing greatest stimulation. However, taurodeoxycholate (0.025-1 mmol/L) had an effect only in the adult and the guanosine 3',5'-cyclic monophosphate (cGMP) activators STa and 8-bromo-cGMP had no effect. CONCLUSIONS: Rabbit distal colonocytes possess inhibitor-sensitive Cl- permeabilities even in neonates. However, the ontogeny of their regulation depends on the secretagogue-signaling pathway. (Gastroenterology 1996 Dec;111(6):1541-50)  相似文献   
96.

Background

Breast deformities in postbariatric surgery (post-BS) patients are different and more challenging than those from non-BS patients. The histological alterations confer the highest clinical consequences to this area: highest degrees of true ptosis, deflated and flattened glands, and totally inelastic covering tissues. Plastic surgeons need an easy-to-use algorithm for technical choices.

Methods

Ptosis and volume loss are the main problems to be corrected on massive-weight-loss (M.W.L.) breasts. Both problems need specific resolutions due to their specific characteristics. Depending on the degree of ptosis and the amount of volume loss, a decisional algorithm has been developed: suitable and advisable techniques are pointed out, minimizing the risk/benefit ratio. “Pros and cons” with the use of mammary implants are emphasized.

Results

A group of 195 postbariatric surgery patients underwent breast contouring since 2001 following the herein presented decisional algorithm. Results have been tested with Body Uneasiness Test: encouraging data pushed to continue this method and to refine it.

Conclusions

Referring to this strategy algorithm, choices 2 and 3 appear to be the more frequently applied and better fitted to cover the majority of M.W.L. breast defects. In the future, the birth and the rise of new mammary implant concepts and technologies could completely change this algorithm.  相似文献   
97.
98.
Macrophage-stimulating protein (MSP) is a scatter factor that causes cell proliferation and migration, and receptor origin nantaise (RON) is its receptor. RON is expressed in macrophages and mesangial cells, and MSP is produced by renal tubular cells. This study investigated whether MSP/RON participate in the pathogenesis of anti-Thy 1 nephritis, a glomerular disease that is characterized by invasion of circulating monocytes into glomeruli and migration and proliferation of mesangial cells. In vivo, renal function and histopathology were studied in rats that had anti-Thy 1 disease and were untreated and treated with a neutralizing anti-MSP antibody. In vitro, whether monocytes express RON and whether MSP has a chemotactic effect on monocytes were studied. In vivo, in anti-Thy 1 disease, MSP was expressed de novo in glomeruli, and neutralization of MSP attenuated the rise in serum creatinine and proteinuria, stopped glomerular neutrophil and monocyte influx, protected from glomerular injury, and lessened mesangial cell overgrowth. In vitro, unstimulated monocytes did not express RON, but the stimulation with LPS induced de novo RON expression. LPS-stimulated monocytes were attracted by MSP. These results demonstrate a pathogenic role of the MSP/RON system in anti-Thy 1 nephritis.  相似文献   
99.

Purpose  

Estimate the prevalence and burden of urinary incontinence (UI) on the quality of life (QOL) among adults (65 or older) with Medigap insurance.  相似文献   
100.
BACKGROUND: Octreotide long acting repeteable (LAR) is a new somatostatin analogue whose activity lasts 28 days. AIM: To assess its therapeutic efficacy, tolerability, and safety in patients with gastroenteropancreatic neuroendocrine tumours. METHODS: A total of 16 patients were studied; 10 patients with carcinoid tumours, three with non-functioning pancreatic tumours, two with Zollinger-Ellison syndrome associated with multiple endocrine neoplasia type 1, and one with glucagonoma were studied. Octreotide LAR was administered intramuscularly at a dose of 20 mg every 28 days for a mean of 10.7 months (range 6-15 months). RESULTS: In carcinoid tumour patients, octreotide LAR normalized bowel movements in nine out of 10 cases, and flushing episodes disappeared in seven out of eight cases. Even in the remaining six patients the symptoms disappeared. In carcinoid tumour patients, urinary 5-hydroxyindoleacetic acid decreased significantly. In the two patients with Zollinger-Ellison syndrome/multiple endocrine neoplasma type 1 and in the patient with glucagonoma, serum gastrin and plasma glucagon, respectively, decreased considerably. Tumour size remained unchanged in 14 out of 16 patients, and increased in the remaining two. No side-effects were observed. CONCLUSIONS: Octreotide LAR appears to have a good therapeutic efficacy, tolerability and safety in the treatment of neuroendocrine tumours. Its effects are similar to those of octreotide and lanreotide. However, because it only needs to be administered once every 28 days, it is preferable in clinical practice.  相似文献   
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